From owner-png-implement@ccrc.wustl.edu Wed Aug 1 00:27:28 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id AAA00784 for ; Wed, 1 Aug 2001 00:27:28 -0500 (CDT) Received: by webshld.ccf.swri.edu; id AAA09446; Wed, 1 Aug 2001 00:25:47 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA3paqCs; Wed, 1 Aug 01 00:25:46 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f715Koo09307 for ; Wed, 1 Aug 2001 00:20:50 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f715R3l23559; Wed, 1 Aug 2001 00:27:03 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f715R2n23554 for ; Wed, 1 Aug 2001 00:27:02 -0500 (CDT) Received: (qmail 22677 invoked from network); 1 Aug 2001 05:27:01 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 1 Aug 2001 05:27:01 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f715P7c02311 for png-implement@ccrc.wustl.edu; Tue, 31 Jul 2001 22:25:07 -0700 Date: Tue, 31 Jul 2001 22:25:07 -0700 Message-Id: <200108010525.f715P7c02311@sonic.net> From: Greg Roelofs To: png-implement@ccrc.wustl.edu Subject: Re: Efficient generation of png images Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Jeremy Ardley wrote: > I am generating geographic map data using typically under 16 colors on a > frame, but potentially 50 or 60 colors. The image has multiple overlapping > sharp edged areas of single color all on a white background. > In my first experiment I am generating an 800 x 600 image and the png file > is about 60K. Is is reasonable for this type of image, or should I look at > pre-converting the image to 8bpp with a palette ? Both, probably. The 900x480, four-color (2-bit) USA map at dslreports.com compresses to 23k as a PNG; double or quadruple the bit depth and you may see the file size double or triple. It very much depends on the kind of map, however--this one has a lot of black regions, but it also has a lot of single-pixel "noise." > I also saw a reference to > filtering as helping compression. I don't understand what that is. Would > it help, and if so, how much? It might help; use pngcrush to find out. > Finally, I am generating text comments (title, author description etc) for > the file, but I don't have a means of reading these back. Is there any > utility suitable for windows that lets me read them to make sure I am > generating the image correctly ? pngcheck -t (or -tv) works pretty well. See http://www.libpng.org/pub/png/apps/pngcheck.html (should be back by tomorrow at the latest; it's already resolving for me tonight). -- Greg Roelofs newt@pobox.com http://pobox.com/~newt/ Newtware, PNG Group, Info-ZIP, Philips Semiconductors, ... -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 1 08:55:05 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id IAA10348 for ; Wed, 1 Aug 2001 08:55:05 -0500 (CDT) Received: by webshld.ccf.swri.edu; id IAA08961; Wed, 1 Aug 2001 08:53:23 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAkZaGFr; Wed, 1 Aug 01 08:53:22 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f71DmKo25235 for ; Wed, 1 Aug 2001 08:48:25 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f71DsOa25923; Wed, 1 Aug 2001 08:54:24 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f71DsNn25919 for ; Wed, 1 Aug 2001 08:54:23 -0500 (CDT) Received: (qmail 19915 invoked from network); 1 Aug 2001 13:54:26 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 1 Aug 2001 13:54:26 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f71DqVN12813 for png-implement@ccrc.wustl.edu; Wed, 1 Aug 2001 06:52:31 -0700 Received: from payco-mxs01.premiere.de ([62.206.58.66]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f71AjPn24952 for ; Wed, 1 Aug 2001 05:45:31 -0500 (CDT) Received: by payco-mxs01.df1.de with Internet Mail Service (5.5.2653.19) id ; Wed, 1 Aug 2001 12:45:20 +0200 Message-ID: From: Martin.Pfingstl@premiereworld.de To: png-implement@ccrc.wustl.edu Subject: Possible bug in libpng Date: Wed, 1 Aug 2001 12:45:10 +0200 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List [non-member submission] Hello, I think I have found a possible bug in libpng 1.0.12: If you try to save a big text chunk using png_text in compressed format (i.e. PNG_TEXT_COMPRESSION_zTXt) (uncompressed works ok) it seems as if the resulting png file cannot be read from almost all other image viewers. Input: char *comment, allocated and freed by my own application. png_text pngtext[4]; pngtext[0].key = "Title"; pngtext[0].text = "Fractal Image"; pngtext[0].compression = PNG_TEXT_COMPRESSION_NONE; pngtext[1].key = "Author"; pngtext[1].text = "ChaosPro"; pngtext[1].compression = PNG_TEXT_COMPRESSION_NONE; pngtext[2].key = "Parameter"; pngtext[2].text = comment; pngtext[2].compression = PNG_TEXT_COMPRESSION_zTXt; ... If the variable "comment" is small (about 2 KB) the png image file is correct. If the comment is huge (about 20KB), the image file is corrupt (Photoshop 5,6, Paintshop Pro 5,6,7, ACDC, Picaview, etc.) I encountered this bug in ChaosPro, a freeware fractal generator: When you save a fractal image, ChaosPro will place the parameter code to correctly recalculate the image inside such text chunks. If the fractals get complicated, the parameters needed to restore the fractal grow and the resulting image is crap. Best regards, Martin Pfingstl -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 1 10:19:46 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id KAA11690 for ; Wed, 1 Aug 2001 10:19:46 -0500 (CDT) Received: by webshld.ccf.swri.edu; id KAA23111; Wed, 1 Aug 2001 10:18:04 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAIHaqiT; Wed, 1 Aug 01 10:18:04 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f71FD7o00083 for ; Wed, 1 Aug 2001 10:13:07 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f71FJPG27390; Wed, 1 Aug 2001 10:19:25 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f71FJOn27386 for ; Wed, 1 Aug 2001 10:19:24 -0500 (CDT) Received: (qmail 28436 invoked from network); 1 Aug 2001 15:19:26 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 1 Aug 2001 15:19:26 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f71FHVO02190 for png-implement@ccrc.wustl.edu; Wed, 1 Aug 2001 08:17:31 -0700 Received: from australis.intranet (ns1.electrosilk.net [203.31.40.1]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f71EgBn26732 for ; Wed, 1 Aug 2001 09:42:11 -0500 (CDT) Received: from ws8 (IDENT:root@www.ardley.org [203.31.40.64]) by australis.intranet (8.9.3/8.9.3) with SMTP id WAA31926 for ; Wed, 1 Aug 2001 22:42:11 +0800 Message-ID: <004301c11a98$21b05540$08281fcb@electrosilk.net> From: "Jeremy Ardley" To: "PNG Implementation List" References: <200108010525.f715P7c02311@sonic.net> Subject: Re: Efficient generation of png images Date: Wed, 1 Aug 2001 22:42:04 +0800 MIME-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Thanks to everyone for their help. I am impressed with this list which seems to be one of the better lists I subscribe to. For information, I have used pngcrush to increase compression. I get 15-20% improvement for 100x time run. In my case I am serving real-time images on a web server (The application is a CGI application) On a cost benefit analysis, it is probably better for me to have a fast generation than a slightly smaller image. Unfortunately for other reasons I probably will have to use manual conversion to 8bpp prior to png generation. I will let the list know how that goes. Thanks Jeremy -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 1 11:09:48 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id LAA12210 for ; Wed, 1 Aug 2001 11:09:48 -0500 (CDT) Received: by webshld.ccf.swri.edu; id LAA01700; Wed, 1 Aug 2001 11:08:06 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAGAaqud; Wed, 1 Aug 01 11:08:06 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f71G39o03139 for ; Wed, 1 Aug 2001 11:03:09 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f71G9GX28259; Wed, 1 Aug 2001 11:09:16 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail17.bigmailbox.com (mail17.bigmailbox.com [209.132.220.48]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f71G9Fn28255 for ; Wed, 1 Aug 2001 11:09:15 -0500 (CDT) Received: by mail17.bigmailbox.com (8.8.7/8.8.7) id JAA03787; Wed, 1 Aug 2001 09:09:19 -0700 Date: Wed, 1 Aug 2001 09:09:19 -0700 Message-Id: <200108011609.JAA03787@mail17.bigmailbox.com> Content-Type: text/plain Content-Disposition: inline Content-Transfer-Encoding: binary X-Mailer: MIME-tools 4.104 (Entity 4.116) Mime-Version: 1.0 X-Originating-Ip: [159.62.105.79] From: "Rich Franzen" To: png-implement@ccrc.wustl.edu Subject: Re: Efficient generation of png images Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Jeremy, Pngcrush does not have to be used inline with production. You can use it in test mode to make decisions concerning how your production should operate. Going to 8-bits will probably be an overall gain, crushed or not. Since you have less than 256 colors anyway, no dithering or other such compression de-optimization need be done. Don't stop there, though. If you know there are only 2 colors, go to a 1-bit image; 4 colors, 2 bits, 16 colors, 4 bits. (I don't think there is a advantage in a 3-bit image. Someone please correct me if I am wrong.) If you don't know ahead of time how many "pens" a given map will need, it is a fairly quick process to do a pre-scan of the pixels. Or even scan as you convert. Perhaps assume that the image will need to be 8 bits, but while converting, count the actual colors found. If there are 16 or fewer, convert again. Or, if most images are known to have less than 16 colors, convert on that 4-bit basis, still counting while you go. If the count reaches 17, start over with an 8-bit conversion. If you can significantly cut the average image size, the time for your user to receive the image may actually be reduced even with this sort of extra processing. (Well, for analog-modem users, anyway.). -- Rich --- http://rocq.home.att.net ------------------------------------------------------------ --== Sent via Deja.com ==-- http://www.deja.com/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 1 13:38:17 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id NAA13505 for ; Wed, 1 Aug 2001 13:38:17 -0500 (CDT) Received: by webshld.ccf.swri.edu; id NAA21650; Wed, 1 Aug 2001 13:36:35 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA_yaisQ; Wed, 1 Aug 01 13:36:34 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f71IVdo11329 for ; Wed, 1 Aug 2001 13:31:39 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f71IbkZ00788; Wed, 1 Aug 2001 13:37:46 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f71Ibjn00783 for ; Wed, 1 Aug 2001 13:37:45 -0500 (CDT) Received: from volans (129.37.161.29) by mail.san.yahoo.com (5.5.039.2) id 3B5F15F2001C3D95 for png-implement@ccrc.wustl.edu; Wed, 1 Aug 2001 11:36:55 -0700 Message-Id: <3.0.3.32.20010801123758.0072cb0c@mail.schaik.com> X-Sender: willemschaik@mail.schaik.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Date: Wed, 01 Aug 2001 12:37:58 -0600 To: PNG Implementation List From: Willem van Schaik Subject: Re: Efficient generation of png images In-Reply-To: <004301c11a98$21b05540$08281fcb@electrosilk.net> References: <200108010525.f715P7c02311@sonic.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Jeremy, Don't remember if you were hooked into the Windows platform, but on Linux or any other Unix box, you could use pnmtopng, followed by pngcrush to get both the conversion to paletted images and then the additional compression of pngcrush. However, because pnmtopng is already optimizing stuff like color-depth and filters, pngcrush usually gives you only little further improvement. Willem At 22:42 01-08-01 +0800, you wrote: >Thanks to everyone for their help. I am impressed with this list which >seems to be one of the better lists I subscribe to. > >For information, I have used pngcrush to increase compression. I get 15-20% >improvement for 100x time run. In my case I am serving real-time images on >a web server (The application is a CGI application) On a cost benefit >analysis, it is probably better for me to have a fast generation than a >slightly smaller image. > >Unfortunately for other reasons I probably will have to use manual >conversion to 8bpp prior to png generation. I will let the list know how >that goes. > >Thanks > >Jeremy > > > > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 1 14:08:04 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id OAA13763 for ; Wed, 1 Aug 2001 14:08:04 -0500 (CDT) Received: by webshld.ccf.swri.edu; id OAA26674; Wed, 1 Aug 2001 14:06:22 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAt0aag0; Wed, 1 Aug 01 14:06:22 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f71J1Qo13156 for ; Wed, 1 Aug 2001 14:01:27 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f71J7k301279; Wed, 1 Aug 2001 14:07:46 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail2.sdc1.sfba.home.com (femail2.sdc1.sfba.home.com [24.0.95.82]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f71J7jn01275 for ; Wed, 1 Aug 2001 14:07:45 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail2.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010801190747.LKQW12480.femail2.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com>; Wed, 1 Aug 2001 12:07:47 -0700 Message-Id: <3.0.6.32.20010801150529.00e0e100@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Wed, 01 Aug 2001 15:05:29 -0400 To: PNG Implementation List From: Glenn Randers-Pehrson Subject: Re: Possible bug in libpng Cc: Martin.Pfingstl@premiereworld.de In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 12:45 PM 8/1/01 +0200, Martin.Pfingstl@premiereworld.de wrote: >If you try to save a big text chunk using png_text in compressed format >(i.e. PNG_TEXT_COMPRESSION_zTXt) (uncompressed works ok) it seems as if the >resulting png file cannot be read from almost all other image viewers. Seems odd that the file cannot be read by "almost all" other image viewers and not "all" others. Can the file, as you imply, be read by some decoders? Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 1 14:14:30 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id OAA13826 for ; Wed, 1 Aug 2001 14:14:30 -0500 (CDT) Received: by webshld.ccf.swri.edu; id OAA27656; Wed, 1 Aug 2001 14:12:48 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAJba4a2; Wed, 1 Aug 01 14:12:48 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f71J7qo13533 for ; Wed, 1 Aug 2001 14:07:52 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f71JELm01379; Wed, 1 Aug 2001 14:14:21 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail15.bigmailbox.com (mail15.bigmailbox.com [209.132.220.46]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f71JEKn01375 for ; Wed, 1 Aug 2001 14:14:20 -0500 (CDT) Received: by mail15.bigmailbox.com (8.8.7/8.8.7) id MAA04943; Wed, 1 Aug 2001 12:14:24 -0700 Date: Wed, 1 Aug 2001 12:14:24 -0700 Message-Id: <200108011914.MAA04943@mail15.bigmailbox.com> Content-Type: text/plain Content-Disposition: inline Content-Transfer-Encoding: binary X-Mailer: MIME-tools 4.104 (Entity 4.116) Mime-Version: 1.0 X-Originating-Ip: [65.33.98.177] From: "Rich Franzen" To: png-implement@ccrc.wustl.edu Subject: Re: Efficient generation of png images Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Cool -- Someone already invented the wheel! Jeremy stated that he was running on a Windows platform. Is there a reason pnmtopng could not be compiled in a cygwin environment? Obviously I haven't ever used pnmtopng, but often text-based 'nix apps are easy to port with cygwin. If no one has already done it, I volunteer to try. -- Rich --- http://rocq.home.att.net >Date: Wed, 01 Aug 2001 12:37:58 -0600 > PNG Implementation List Willem van Schaik Re: Efficient generation of png imagesReply-To: PNG Implementation List > >Jeremy, > >Don't remember if you were hooked into the Windows platform, but on Linux >or any other Unix box, you could use pnmtopng, followed by pngcrush to get >both the conversion to paletted images and then the additional compression >of pngcrush. However, because pnmtopng is already optimizing stuff like >color-depth and filters, pngcrush usually gives you only little further >improvement. > >Willem ------------------------------------------------------------ --== Sent via Deja.com ==-- http://www.deja.com/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 2 07:51:47 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id HAA19219 for ; Thu, 2 Aug 2001 07:51:46 -0500 (CDT) Received: by webshld.ccf.swri.edu; id HAA25140; Thu, 2 Aug 2001 07:50:04 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAMka4fX; Thu, 2 Aug 01 07:50:03 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f72Cj7o21194 for ; Thu, 2 Aug 2001 07:45:07 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f72CpJr08953; Thu, 2 Aug 2001 07:51:19 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f72CpIn08949 for ; Thu, 2 Aug 2001 07:51:18 -0500 (CDT) Received: from volans (129.37.150.51) by mail.san.yahoo.com (5.5.039.2) id 3B5F15F2001FA077 for png-implement@ccrc.wustl.edu; Thu, 2 Aug 2001 05:50:26 -0700 Message-Id: <3.0.3.32.20010801144138.00728494@mail.schaik.com> X-Sender: willemschaik@mail.schaik.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Date: Wed, 01 Aug 2001 14:41:38 -0600 To: PNG Implementation List From: Willem van Schaik Subject: Re: Efficient generation of png images In-Reply-To: <200108011914.MAA04943@mail15.bigmailbox.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Rich wrote: >Jeremy stated that he was running on a Windows platform. Is there a >reason pnmtopng could not be compiled in a cygwin environment? >Obviously I haven't ever used pnmtopng, but often text-based 'nix apps >are easy to port with cygwin. There are pnmtopng binaries for MSDOS (using a DOS extender), but they don't run in Windows. I would look forward if you managed to compile under cygwin, the real issue is that for pnmtopng you have to build the netpbm library. I gave that one a try with Visual-C, but that was quite hopeless. Willem At 12:14 01-08-01 -0700, you wrote: >Cool -- Someone already invented the wheel! >Jeremy stated that he was running on a Windows platform. Is there a >reason pnmtopng could not be compiled in a cygwin environment? >Obviously I haven't ever used pnmtopng, but often text-based 'nix apps >are easy to port with cygwin. > >If no one has already done it, I volunteer to try. > >-- Rich >--- http://rocq.home.att.net > > >>Date: Wed, 01 Aug 2001 12:37:58 -0600 >> PNG Implementation List Willem van Schaik Re: Efficient generation of png imagesReply-To: PNG Implementation List >> >>Jeremy, >> >>Don't remember if you were hooked into the Windows platform, but on Linux >>or any other Unix box, you could use pnmtopng, followed by pngcrush to get >>both the conversion to paletted images and then the additional compression >>of pngcrush. However, because pnmtopng is already optimizing stuff like >>color-depth and filters, pngcrush usually gives you only little further >>improvement. >> >>Willem > > > > >------------------------------------------------------------ >--== Sent via Deja.com ==-- >http://www.deja.com/ > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 2 09:46:42 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id JAA20021 for ; Thu, 2 Aug 2001 09:46:42 -0500 (CDT) Received: by webshld.ccf.swri.edu; id JAA13750; Thu, 2 Aug 2001 09:45:00 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAwQai2A; Thu, 2 Aug 01 09:44:59 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f72Ee3o26850 for ; Thu, 2 Aug 2001 09:40:03 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f72EkGg10334; Thu, 2 Aug 2001 09:46:16 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f72EkFn10329 for ; Thu, 2 Aug 2001 09:46:15 -0500 (CDT) Received: (qmail 19541 invoked from network); 2 Aug 2001 14:45:38 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 2 Aug 2001 14:45:38 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f72Ehfn16970 for png-implement@ccrc.wustl.edu; Thu, 2 Aug 2001 07:43:41 -0700 Date: Thu, 2 Aug 2001 07:43:41 -0700 Message-Id: <200108021443.f72Ehfn16970@sonic.net> From: Greg Roelofs To: png-implement@ccrc.wustl.edu Subject: Re: Efficient generation of png images Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List >>Jeremy stated that he was running on a Windows platform. Is there a >>reason pnmtopng could not be compiled in a cygwin environment? >>Obviously I haven't ever used pnmtopng, but often text-based 'nix apps >>are easy to port with cygwin. > There are pnmtopng binaries for MSDOS (using a DOS extender), but they > don't run in Windows. I would look forward if you managed to compile under > cygwin, the real issue is that for pnmtopng you have to build the netpbm > library. I gave that one a try with Visual-C, but that was quite hopeless. See http://gnuwin32.sourceforge.net/packages.html , specifically the "NetPbm" link. A version of pnmtopng is included in that (at least in 9.15; I'm pretty sure 9.14, too). And there may already be a new-NetPBM port to Cygwin, but I happened to come across this one a couple of days ago. Related sites: http://pw32.sourceforge.net/ http://mingwrep.sourceforge.net/ http://www.mingw.org/x86-win32-ports.shtml Greg -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 2 16:53:46 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id QAA23651 for ; Thu, 2 Aug 2001 16:53:46 -0500 (CDT) Received: by webshld.ccf.swri.edu; id QAA20387; Thu, 2 Aug 2001 16:52:03 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAevai0N; Thu, 2 Aug 01 16:52:02 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f72Ll5N20769 for ; Thu, 2 Aug 2001 16:47:05 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f72Lq3d19366; Thu, 2 Aug 2001 16:52:03 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from genesis.tmfi.com ([199.103.206.10]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f72Lpwn19359 for ; Thu, 2 Aug 2001 16:52:02 -0500 (CDT) Received: from sanjuan ([199.103.206.208]) by genesis.tmfi.com with Microsoft SMTPSVC(5.0.2195.2966); Thu, 2 Aug 2001 17:50:43 -0400 From: "Carlos Rodriguez" To: "PNG Implementation List" Subject: newbie question Date: Thu, 2 Aug 2001 17:50:43 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.00.3018.1300 In-Reply-To: <3.0.3.32.20010801144138.00728494@mail.schaik.com> X-OriginalArrivalTime: 02 Aug 2001 21:50:43.0139 (UTC) FILETIME=[2D913130:01C11B9D] Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List I am a complete newbie to libpng, and I was wondering if anyone could answer the following question that's come up while going thru libpng.txt. I refer to the following fragment: png_infop info_ptr = png_create_info_struct(png_ptr); if (!info_ptr) { png_destroy_read_struct(&png_ptr, (png_infopp)NULL, (png_infopp)NULL); return (ERROR); } png_infop end_info = png_create_info_struct(png_ptr); if (!end_info) { png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)NULL); return (ERROR); } I ask because functions like png_destroy_read_struct want two png_info pointers, and it's not clear (to me) from pngread.c what the purpose of the second png_info ptr is. Best Regards -Carlos Rodriguez -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 2 20:53:52 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id UAA24851 for ; Thu, 2 Aug 2001 20:53:52 -0500 (CDT) Received: by webshld.ccf.swri.edu; id UAA08499; Thu, 2 Aug 2001 20:52:09 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAEFaqMq; Thu, 2 Aug 01 20:52:08 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f731lBN00315 for ; Thu, 2 Aug 2001 20:47:11 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f731rLM21483; Thu, 2 Aug 2001 20:53:21 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail7.sdc1.sfba.home.com (femail7.sdc1.sfba.home.com [24.0.95.87]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f731rKn21479 for ; Thu, 2 Aug 2001 20:53:20 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail7.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010803015313.CKEP20845.femail7.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com>; Thu, 2 Aug 2001 18:53:13 -0700 Message-Id: <3.0.6.32.20010802215057.00e126a0@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Thu, 02 Aug 2001 21:50:57 -0400 To: PNG Implementation List From: Glenn Randers-Pehrson Subject: Re: newbie question Cc: "PNG Implementation List" In-Reply-To: References: <3.0.3.32.20010801144138.00728494@mail.schaik.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 05:50 PM 8/2/01 -0400, Carlos Rodriguez wrote: > it's not clear (to me) from pngread.c what the purpose of the >second png_info ptr is. The first info_ptr contains data that appears before the IDAT chunks, and the second contains data that appears after the IDAT chunks. Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 2 22:26:28 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id WAA25156 for ; Thu, 2 Aug 2001 22:26:28 -0500 (CDT) Received: by webshld.ccf.swri.edu; id WAA11870; Thu, 2 Aug 2001 22:24:45 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAl_aGlx; Thu, 2 Aug 01 22:24:44 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f733JkN02891 for ; Thu, 2 Aug 2001 22:19:47 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f733Q8c22492; Thu, 2 Aug 2001 22:26:08 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from genesis.tmfi.com ([199.103.206.10]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f733Q6n22488 for ; Thu, 2 Aug 2001 22:26:06 -0500 (CDT) Received: from sanjuan ([208.192.101.156]) by genesis.tmfi.com with Microsoft SMTPSVC(5.0.2195.2966); Thu, 2 Aug 2001 23:24:52 -0400 From: "Carlos Rodriguez" To: "PNG Implementation List" Subject: RE: newbie question Date: Thu, 2 Aug 2001 23:24:49 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) In-Reply-To: <3.0.6.32.20010802215057.00e126a0@netmail.home.com> Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.00.3018.1300 X-OriginalArrivalTime: 03 Aug 2001 03:24:53.0339 (UTC) FILETIME=[DC6AEAB0:01C11BCB] Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List that makes sense Thanks! -----Original Message----- From: owner-png-implement@ccrc.wustl.edu [mailto:owner-png-implement@ccrc.wustl.edu]On Behalf Of Glenn Randers-Pehrson Sent: Thursday, August 02, 2001 9:51 PM To: PNG Implementation List Cc: PNG Implementation List Subject: Re: newbie question At 05:50 PM 8/2/01 -0400, Carlos Rodriguez wrote: > it's not clear (to me) from pngread.c what the purpose of the >second png_info ptr is. The first info_ptr contains data that appears before the IDAT chunks, and the second contains data that appears after the IDAT chunks. Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Fri Aug 3 11:33:34 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id LAA29378 for ; Fri, 3 Aug 2001 11:33:33 -0500 (CDT) Received: by webshld.ccf.swri.edu; id LAA08357; Fri, 3 Aug 2001 11:31:50 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAHGaGuq; Fri, 3 Aug 01 11:31:49 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f73GQqN29253 for ; Fri, 3 Aug 2001 11:26:52 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f73GWmb00771; Fri, 3 Aug 2001 11:32:48 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from genesis.tmfi.com ([199.103.206.10]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f73GWln00767 for ; Fri, 3 Aug 2001 11:32:47 -0500 (CDT) Received: from sanjuan ([199.103.206.208]) by genesis.tmfi.com with Microsoft SMTPSVC(5.0.2195.2966); Fri, 3 Aug 2001 12:31:30 -0400 From: "Carlos Rodriguez" To: "PNG Implementation List" Subject: writing a 16 bit grayscale png Date: Fri, 3 Aug 2001 12:31:29 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) In-Reply-To: <3.0.6.32.20010802215057.00e126a0@netmail.home.com> X-MimeOLE: Produced By Microsoft MimeOLE V5.00.3018.1300 Importance: Normal X-OriginalArrivalTime: 03 Aug 2001 16:31:30.0029 (UTC) FILETIME=[BFD649D0:01C11C39] Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List People: I am trying to write a simple program that creates a 16-bit grayscale png. This will consists of repeated bands of gradients from black to some level of gray. Unfortunately the image I am getting does not look correct, though I cannot find what is wrong. I submit the relevant code for your amusement (I've ommited all of the struct allocation and IO for clarity) : #define COLS 1000 #define ROWS 100 #define ROWBYTES 2 . . . . // //Second test, write an array of random //bytes to a png. As usual we do the gradient to gray //thing // short color = 0; for (int y = 0; y < ROWS; y++) { for(int x = 0; x < COLS; color++) { png_byte higher = (color >> 8); png_byte lower = (color); actual_bytes[x++] = (png_byte)higher; actual_bytes[x++] = (png_byte)lower; } //store the pointer to this row in image_data image_data[y] = actual_bytes; //point to the next row actual_bytes = actual_bytes+(COLS*ROWBYTES); } // //open a file for writing // char *out_file = "C:\\my_real_16_bit.png"; fp = fopen(out_file, "wb"); . . //allocate png_struct, png_info, initIO, setjmp, etc . // //start filling out the info structure // png_set_IHDR(w_png_ptr, w_info_ptr, COLS /*width*/, ROWS /*height*/, 16 /*bit_depth*/, PNG_COLOR_TYPE_GRAY /*color_type*/, PNG_INTERLACE_NONE /*interlace_type*/, PNG_COMPRESSION_TYPE_DEFAULT /*compression_type*/, PNG_FILTER_TYPE_DEFAULT /*filter_method*/); // //do set rows to set image data // png_set_rows(w_png_ptr, w_info_ptr, image_data); // //we should be able to write now // png_write_png(w_png_ptr, w_info_ptr, PNG_TRANSFORM_IDENTITY, NULL); . .//clanup, free the mallocs, etc. . Any help is appreciated, thanks Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Fri Aug 3 14:31:06 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id OAA00732 for ; Fri, 3 Aug 2001 14:31:06 -0500 (CDT) Received: by webshld.ccf.swri.edu; id OAA29986; Fri, 3 Aug 2001 14:29:22 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAATkaaK6; Fri, 3 Aug 01 14:29:22 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f73JOON07867 for ; Fri, 3 Aug 2001 14:24:24 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f73JUja06033; Fri, 3 Aug 2001 14:30:45 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail5.sdc1.sfba.home.com (femail5.sdc1.sfba.home.com [24.0.95.85]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f73JUin06029 for ; Fri, 3 Aug 2001 14:30:44 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail5.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010803193046.YEZU24816.femail5.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com> for ; Fri, 3 Aug 2001 12:30:46 -0700 Message-Id: <3.0.6.32.20010803152827.00e015c0@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Fri, 03 Aug 2001 15:28:27 -0400 To: PNG Implementation List From: Glenn Randers-Pehrson Subject: Re: writing a 16 bit grayscale png In-Reply-To: References: <3.0.6.32.20010802215057.00e126a0@netmail.home.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 12:31 PM 8/3/01 -0400, Carlos Rodriguez wrote: > short color = 0; > for (int y = 0; y < ROWS; y++) { > for(int x = 0; x < COLS; color++) Shouldn't that be x < COLS*ROWBYTES ? Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Fri Aug 3 15:13:53 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id PAA01054 for ; Fri, 3 Aug 2001 15:13:53 -0500 (CDT) Received: by webshld.ccf.swri.edu; id PAA05723; Fri, 3 Aug 2001 15:12:09 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAg7aqll; Fri, 3 Aug 01 15:12:09 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f73K7AN09899 for ; Fri, 3 Aug 2001 15:07:11 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f73KDdM06872; Fri, 3 Aug 2001 15:13:39 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from genesis.tmfi.com ([199.103.206.10]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f73KDcn06868 for ; Fri, 3 Aug 2001 15:13:39 -0500 (CDT) Received: from sanjuan ([199.103.206.208]) by genesis.tmfi.com with Microsoft SMTPSVC(5.0.2195.2966); Fri, 3 Aug 2001 16:12:22 -0400 From: "Carlos Rodriguez" To: "PNG Implementation List" Subject: RE: writing a 16 bit grayscale png Date: Fri, 3 Aug 2001 16:12:22 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) In-Reply-To: <3.0.6.32.20010803152827.00e015c0@netmail.home.com> X-MimeOLE: Produced By Microsoft MimeOLE V5.00.3018.1300 Importance: Normal X-OriginalArrivalTime: 03 Aug 2001 20:12:22.0491 (UTC) FILETIME=[9AEB82B0:01C11C58] Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Thanks for your reply, Glenn: In answer to your question, no, because if you'll notice the x will get post-incremented twice in the body of the loop, so while each row is COLS*ROWBYTES bytes long, each inner loop only executes COLS times (because the samples are two bytes long. I'm trying to get each row to go from 0 to 999 for a grayscale index. This is the color variable, which gets incremented on the loop and gets written to every two consecutive bytes. SO I expect to see a smoth gradient from left to right. Instead I get 4 gradients. I wonder if this is a DISPLAY limitation. BTW, there was a bug in the 1st code I sent, which I have fixed. Still the same problem though. Revised code (with a malloc per row, to see if that makes a difference) follows: for(int y = 0; y < ROWS; y++) { png_bytep rowptr = (png_bytep)malloc(COLS*ROWBYTES*sizeof(png_byte)); short color = 0; for (int x = 0; x < COLS; color++) { png_byte higher = (0x00ff) & (color >> 8); png_byte lower = (0x00ff) & (color); rowptr[x++] = (png_byte)higher; rowptr[x++] = (png_byte)lower; } image_data[y] = rowptr; } -----Original Message----- From: owner-png-implement@ccrc.wustl.edu [mailto:owner-png-implement@ccrc.wustl.edu]On Behalf Of Glenn Randers-Pehrson Sent: Friday, August 03, 2001 3:28 PM To: PNG Implementation List Subject: Re: writing a 16 bit grayscale png At 12:31 PM 8/3/01 -0400, Carlos Rodriguez wrote: > short color = 0; > for (int y = 0; y < ROWS; y++) { > for(int x = 0; x < COLS; color++) Shouldn't that be x < COLS*ROWBYTES ? Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Fri Aug 3 16:56:57 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id QAA01904 for ; Fri, 3 Aug 2001 16:56:57 -0500 (CDT) Received: by webshld.ccf.swri.edu; id QAA20828; Fri, 3 Aug 2001 16:55:13 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAALRayRO; Fri, 3 Aug 01 16:55:13 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f73LoGN15081 for ; Fri, 3 Aug 2001 16:50:17 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f73LuFk09272; Fri, 3 Aug 2001 16:56:15 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail13.bigmailbox.com (mail13.bigmailbox.com [209.132.220.44]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f73LuEn09268 for ; Fri, 3 Aug 2001 16:56:14 -0500 (CDT) Received: by mail13.bigmailbox.com (8.8.7/8.8.7) id OAA00843; Fri, 3 Aug 2001 14:56:20 -0700 Date: Fri, 3 Aug 2001 14:56:20 -0700 Message-Id: <200108032156.OAA00843@mail13.bigmailbox.com> Content-Type: text/plain Content-Disposition: inline Content-Transfer-Encoding: binary X-Mailer: MIME-tools 4.104 (Entity 4.116) Mime-Version: 1.0 X-Originating-Ip: [65.33.98.177] From: "Rich Franzen" To: png-implement@ccrc.wustl.edu Subject: RE: writing a 16 bit grayscale png Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Carlos, Try looking at the image in a different viewer or on another platform. Seeing four ramps per line could mean the viewer was not tested well in its handling of 16-bit pixels, and is choosing to display the low-order, not high-order byte. Since you are only going to 999 out of 65,535, expect any viewer to display the image very darkly. It will need to apply some gain or gamma to see the ramp you expect. Try ImageMagick, compiled to handle 16-bit pixels. Many programs out there, even the well-debugged ones, are not really good with 16-bit greyscale. They typically treat the image as 8-bit data, and simplistically chop-off the low-order byte. In the case of your ramp, the resultant image would have only three values. You would see 256 zeros, 256 ones, 256 twos, and 232 threes -- not quite the ramp you want... My pseudogrey page (signature block) discusses one methodology to work with "deep-grey" in a 24-bit color environment. And, to test your viewer, here is a link to a 16-bit "square snake" with all greys: http://rocq.home.att.net/images/64kSnake.png -- Rich --- http://rocq.home.att.net/pseudoGrey.html > "Carlos Rodriguez" "PNG Implementation List" RE: writing a 16 bit grayscale pngDate: Fri, 3 Aug 2001 16:12:22 -0400 >Reply-To: PNG Implementation List > >Thanks for your reply, Glenn: > >In answer to your question, no, because if you'll notice the x will get >post-incremented twice in the body of the loop, so while each row is >COLS*ROWBYTES bytes long, each inner loop only executes COLS times (because >the samples are two bytes long. I'm trying to get each row to go from 0 to >999 for a grayscale index. This is the color variable, which gets >incremented on the loop and gets written to every two consecutive bytes. SO >I expect to see a smoth gradient from left to right. Instead I get 4 >gradients. I wonder if this is a DISPLAY limitation. > >BTW, there was a bug in the 1st code I sent, which I have fixed. Still the >same problem though. >Revised code (with a malloc per row, to see if that makes a difference) >follows: > >for(int y = 0; y < ROWS; y++) >{ > png_bytep rowptr = (png_bytep)malloc(COLS*ROWBYTES*sizeof(png_byte)); > short color = 0; > for (int x = 0; x < COLS; color++) { > png_byte higher = (0x00ff) & (color >> 8); > png_byte lower = (0x00ff) & (color); > rowptr[x++] = (png_byte)higher; > rowptr[x++] = (png_byte)lower; > } > image_data[y] = rowptr; >} > ------------------------------------------------------------ --== Sent via Deja.com ==-- http://www.deja.com/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Fri Aug 3 18:31:29 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id SAA02299 for ; Fri, 3 Aug 2001 18:31:29 -0500 (CDT) Received: by webshld.ccf.swri.edu; id SAA27905; Fri, 3 Aug 2001 18:29:45 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAdwaaG2; Fri, 3 Aug 01 18:29:44 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f73NOmN18912 for ; Fri, 3 Aug 2001 18:24:48 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f73NRFF10028; Fri, 3 Aug 2001 18:27:15 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from lynx.adilger.int (124-205.dialup.ucalgary.ca [136.159.124.205]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f73NQon10022 for ; Fri, 3 Aug 2001 18:26:57 -0500 (CDT) Received: (from adilger@localhost) by lynx.adilger.int (8.11.2/8.11.2) id f73MMnp01720 for png-implement@ccrc.wustl.edu; Fri, 3 Aug 2001 16:22:49 -0600 From: Andreas Dilger Message-Id: <200108032222.f73MMnp01720@lynx.adilger.int> Subject: Re: newbie question To: png-implement@ccrc.wustl.edu Date: Fri, 3 Aug 2001 16:22:49 -0600 (MDT) In-Reply-To: from "Carlos Rodriguez" at Aug 02, 2001 05:50:43 PM X-Mailer: ELM [version 2.5 PL0pre8] MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Carlos Rodriguez writes: > I ask because functions like png_destroy_read_struct want two png_info > pointers, and it's not clear (to me) from pngread.c what the purpose of the > second png_info ptr is. For a limited number of PNG chunks (tEXt, zTXt, others?), you can write them either before or after the main body of the image. You attach these chunks to the png_info struct you want, and one is the "before" struct and one is the "after" struct. In many cases, you only need the "before" struct, but if you have large tEXt chunks, or other ancillary data that is not required to view the image, it can be put after the main image data and does not slow down image loading. Cheers, Andreas -- Andreas Dilger http://sourceforge.net/projects/ext2resize/ http://www-mddsp.enel.ucalgary.ca/People/adilger/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sat Aug 4 14:24:30 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id OAA06095 for ; Sat, 4 Aug 2001 14:24:29 -0500 (CDT) Received: by webshld.ccf.swri.edu; id OAA03856; Sat, 4 Aug 2001 14:22:45 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAo2a4Hh; Sat, 4 Aug 01 14:22:44 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f74JHgN16287 for ; Sat, 4 Aug 2001 14:17:42 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f74JNe502664; Sat, 4 Aug 2001 14:23:40 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from genesis.tmfi.com ([199.103.206.10]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f74JNc502660 for ; Sat, 4 Aug 2001 14:23:39 -0500 (CDT) Received: from sanjuan ([208.192.102.79]) by genesis.tmfi.com with Microsoft SMTPSVC(5.0.2195.2966); Sat, 4 Aug 2001 15:22:22 -0400 From: "Carlos Rodriguez" To: "PNG Implementation List" Subject: RE: writing a 16 bit grayscale png Date: Sat, 4 Aug 2001 15:22:22 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.00.3018.1300 In-Reply-To: <200108032156.OAA00843@mail13.bigmailbox.com> X-OriginalArrivalTime: 04 Aug 2001 19:22:23.0270 (UTC) FILETIME=[C9A87460:01C11D1A] Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Hi Rich: Man, you page rocks. I have been schooled! Anyway, thanks for the feedback. I confirmed your theory on the crappy viewers by modifying my test code to write 256 rows of 256 pixels, from 0 to 2^16. What you would expect is a gradual fade from left to right and top to bottom. What you see is a ramp from top to bottom, consistent with the discard of the lower byte on each pixel (since the high-order byte remains constant per each row). Hmmm, I guess pseudogrey is the way to go. It is striking how pathetic support for this is in Windows. Neither Photoshop 5.0, nor the QuickTime player, much less the web browsers, were able to display this correctly. What is more, Photoshop actually says that it is an 8-bit image! Sad... -----Original Message----- From: owner-png-implement@ccrc.wustl.edu [mailto:owner-png-implement@ccrc.wustl.edu]On Behalf Of Rich Franzen Sent: Friday, August 03, 2001 5:56 PM To: png-implement@ccrc.wustl.edu Subject: RE: writing a 16 bit grayscale png Carlos, Try looking at the image in a different viewer or on another platform. Seeing four ramps per line could mean the viewer was not tested well in its handling of 16-bit pixels, and is choosing to display the low-order, not high-order byte. Since you are only going to 999 out of 65,535, expect any viewer to display the image very darkly. It will need to apply some gain or gamma to see the ramp you expect. Try ImageMagick, compiled to handle 16-bit pixels. Many programs out there, even the well-debugged ones, are not really good with 16-bit greyscale. They typically treat the image as 8-bit data, and simplistically chop-off the low-order byte. In the case of your ramp, the resultant image would have only three values. You would see 256 zeros, 256 ones, 256 twos, and 232 threes -- not quite the ramp you want... My pseudogrey page (signature block) discusses one methodology to work with "deep-grey" in a 24-bit color environment. And, to test your viewer, here is a link to a 16-bit "square snake" with all greys: http://rocq.home.att.net/images/64kSnake.png -- Rich --- http://rocq.home.att.net/pseudoGrey.html > "Carlos Rodriguez" "PNG Implementation List" RE: writing a 16 bit grayscale pngDate: Fri, 3 Aug 2001 16:12:22 -0400 >Reply-To: PNG Implementation List > >Thanks for your reply, Glenn: > >In answer to your question, no, because if you'll notice the x will get >post-incremented twice in the body of the loop, so while each row is >COLS*ROWBYTES bytes long, each inner loop only executes COLS times (because >the samples are two bytes long. I'm trying to get each row to go from 0 to >999 for a grayscale index. This is the color variable, which gets >incremented on the loop and gets written to every two consecutive bytes. SO >I expect to see a smoth gradient from left to right. Instead I get 4 >gradients. I wonder if this is a DISPLAY limitation. > >BTW, there was a bug in the 1st code I sent, which I have fixed. Still the >same problem though. >Revised code (with a malloc per row, to see if that makes a difference) >follows: > >for(int y = 0; y < ROWS; y++) >{ > png_bytep rowptr = (png_bytep)malloc(COLS*ROWBYTES*sizeof(png_byte)); > short color = 0; > for (int x = 0; x < COLS; color++) { > png_byte higher = (0x00ff) & (color >> 8); > png_byte lower = (0x00ff) & (color); > rowptr[x++] = (png_byte)higher; > rowptr[x++] = (png_byte)lower; > } > image_data[y] = rowptr; >} > ------------------------------------------------------------ --== Sent via Deja.com ==-- http://www.deja.com/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sat Aug 4 19:01:28 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id TAA06771 for ; Sat, 4 Aug 2001 19:01:28 -0500 (CDT) Received: by webshld.ccf.swri.edu; id SAA10003; Sat, 4 Aug 2001 18:59:43 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAFjaqIt; Sat, 4 Aug 01 18:59:43 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f74NsjN21365 for ; Sat, 4 Aug 2001 18:54:45 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7500DH04743; Sat, 4 Aug 2001 19:00:13 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail21.bigmailbox.com (mail21.bigmailbox.com [209.132.220.195]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7500C504739 for ; Sat, 4 Aug 2001 19:00:12 -0500 (CDT) Received: by mail21.bigmailbox.com (8.8.7/8.8.7) id RAA22291; Sat, 4 Aug 2001 17:00:19 -0700 Date: Sat, 4 Aug 2001 17:00:19 -0700 Message-Id: <200108050000.RAA22291@mail21.bigmailbox.com> Content-Type: text/plain Content-Disposition: inline Content-Transfer-Encoding: binary X-Mailer: MIME-tools 4.104 (Entity 4.116) Mime-Version: 1.0 X-Originating-Ip: [65.33.98.177] From: "Rich Franzen" To: png-implement@ccrc.wustl.edu Subject: RE: writing a 16 bit grayscale png Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Carlos, Thanks. I am not trying to "school" anyone, but those of us who occasionally need "deep grey" (more than 8 bits) are in a decided minority. I've been working with such images for about 14 years, so I don't mind sharing a trick or two. Concerning lack of support for 16 bits, it is sad, but also understandable. ImageMagick can be compiled to support 16-bit imagery, but then _everything_ is promoted to 16 bits. A 24-bit color image doubles in memory usage to 48 bits total per pixel. There is a reason for this. Put yourself in the shoes of the imaging program author. You provide a nice set of imaging features. It is quick, reliable, well-tested and absolutely nifty. Now along comes PNG with its 16-bit greyscale capability and 48-bit color capacity. Do you rewrite all your logic to support a new universe? In some operations, you would have to support input from a 24-bit source and a 48-bit source, so there is a lot of complexity to handle and test. And there are very few 16-bit and 48-bit iamges to use as test data. This is why most programs stick with their 8:24 universe. It is why scanners which can do 30 or 36 (etc.) bits per pixel generally output only 24. And it is why ImageMagick is either compiled for 8:24 or 16:48. If you want to use pseudogrey and PhotoShop, there is at least one plug-in already. At the bottom of my pseudogrey page, there is a link to Adam Stanislav's "www.RedPrince.net" site. He has a suite of plug-ins called "Pixie Dust", which includes pseudogrey. (I have not actually used it -- I don't have PhotoShop. But his example images are impressive.) -- Rich --- http://rocq.home.att.net > "Carlos Rodriguez" "PNG Implementation List" RE: writing a 16 bit grayscale pngDate: Sat, 4 Aug 2001 15:22:22 -0400 > >Hi Rich: > >Man, you page rocks. I have been schooled! > >Anyway, thanks for the feedback. I confirmed your theory on the crappy >viewers by modifying my test code to write 256 rows of 256 pixels, from 0 to >2^16. What you would expect is a gradual fade from left to right and top to >bottom. What you see is a ramp from top to bottom, consistent with the >discard of the lower byte on each pixel (since the high-order byte remains >constant per each row). Hmmm, I guess pseudogrey is the way to go. > >It is striking how pathetic support for this is in Windows. Neither >Photoshop 5.0, nor the QuickTime player, much less the web browsers, were >able to display this correctly. What is more, Photoshop actually says that >it is an 8-bit image! Sad... ------------------------------------------------------------ --== Sent via Deja.com ==-- http://www.deja.com/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sat Aug 4 21:07:39 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id VAA07158 for ; Sat, 4 Aug 2001 21:07:39 -0500 (CDT) Received: by webshld.ccf.swri.edu; id VAA12729; Sat, 4 Aug 2001 21:05:54 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAJGaa3y; Sat, 4 Aug 01 21:05:54 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7520tN23740 for ; Sat, 4 Aug 2001 21:00:56 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7527IW05777; Sat, 4 Aug 2001 21:07:18 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from genesis.tmfi.com ([199.103.206.10]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7527E505772 for ; Sat, 4 Aug 2001 21:07:14 -0500 (CDT) Received: from sanjuan ([208.192.101.8]) by genesis.tmfi.com with Microsoft SMTPSVC(5.0.2195.2966); Sat, 4 Aug 2001 22:06:00 -0400 From: "Carlos Rodriguez" To: "PNG Implementation List" Subject: RE: writing a 16 bit grayscale png Date: Sat, 4 Aug 2001 22:05:59 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) x-mimeole: Produced By Microsoft MimeOLE V5.00.3018.1300 Importance: Normal In-Reply-To: <200108050000.RAA22291@mail21.bigmailbox.com> X-OriginalArrivalTime: 05 Aug 2001 02:06:00.0982 (UTC) FILETIME=[2C8A0B60:01C11D53] Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List agreed, I was a bit harsh. What I am trying to do (if you haven't guessed) is DICOM 16-bit gray that will display on a browser as such (without plug-ins or client side code) png was chosen because it can do 16-g and it's lossless. I will attempt pseudo-gray and see how that goes Thanks -----Original Message----- From: owner-png-implement@ccrc.wustl.edu [mailto:owner-png-implement@ccrc.wustl.edu]On Behalf Of Rich Franzen Sent: Saturday, August 04, 2001 8:00 PM To: png-implement@ccrc.wustl.edu Subject: RE: writing a 16 bit grayscale png Carlos, Thanks. I am not trying to "school" anyone, but those of us who occasionally need "deep grey" (more than 8 bits) are in a decided minority. I've been working with such images for about 14 years, so I don't mind sharing a trick or two. Concerning lack of support for 16 bits, it is sad, but also understandable. ImageMagick can be compiled to support 16-bit imagery, but then _everything_ is promoted to 16 bits. A 24-bit color image doubles in memory usage to 48 bits total per pixel. There is a reason for this. Put yourself in the shoes of the imaging program author. You provide a nice set of imaging features. It is quick, reliable, well-tested and absolutely nifty. Now along comes PNG with its 16-bit greyscale capability and 48-bit color capacity. Do you rewrite all your logic to support a new universe? In some operations, you would have to support input from a 24-bit source and a 48-bit source, so there is a lot of complexity to handle and test. And there are very few 16-bit and 48-bit iamges to use as test data. This is why most programs stick with their 8:24 universe. It is why scanners which can do 30 or 36 (etc.) bits per pixel generally output only 24. And it is why ImageMagick is either compiled for 8:24 or 16:48. If you want to use pseudogrey and PhotoShop, there is at least one plug-in already. At the bottom of my pseudogrey page, there is a link to Adam Stanislav's "www.RedPrince.net" site. He has a suite of plug-ins called "Pixie Dust", which includes pseudogrey. (I have not actually used it -- I don't have PhotoShop. But his example images are impressive.) -- Rich --- http://rocq.home.att.net > "Carlos Rodriguez" "PNG Implementation List" RE: writing a 16 bit grayscale pngDate: Sat, 4 Aug 2001 15:22:22 -0400 > >Hi Rich: > >Man, you page rocks. I have been schooled! > >Anyway, thanks for the feedback. I confirmed your theory on the crappy >viewers by modifying my test code to write 256 rows of 256 pixels, from 0 to >2^16. What you would expect is a gradual fade from left to right and top to >bottom. What you see is a ramp from top to bottom, consistent with the >discard of the lower byte on each pixel (since the high-order byte remains >constant per each row). Hmmm, I guess pseudogrey is the way to go. > >It is striking how pathetic support for this is in Windows. Neither >Photoshop 5.0, nor the QuickTime player, much less the web browsers, were >able to display this correctly. What is more, Photoshop actually says that >it is an 8-bit image! Sad... ------------------------------------------------------------ --== Sent via Deja.com ==-- http://www.deja.com/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sat Aug 4 23:40:13 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id XAA07583 for ; Sat, 4 Aug 2001 23:40:12 -0500 (CDT) Received: by webshld.ccf.swri.edu; id XAA16108; Sat, 4 Aug 2001 23:38:28 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAHqayDF; Sat, 4 Aug 01 23:38:27 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f754XTN26461 for ; Sat, 4 Aug 2001 23:33:29 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f754dn106888; Sat, 4 Aug 2001 23:39:49 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f754dm506884 for ; Sat, 4 Aug 2001 23:39:48 -0500 (CDT) Received: (qmail 22066 invoked from network); 5 Aug 2001 04:39:53 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 5 Aug 2001 04:39:53 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f754bqn22085 for png-implement@ccrc.wustl.edu; Sat, 4 Aug 2001 21:37:52 -0700 Date: Sat, 4 Aug 2001 21:37:52 -0700 Message-Id: <200108050437.f754bqn22085@sonic.net> From: Greg Roelofs To: png-implement@ccrc.wustl.edu Subject: RE: writing a 16 bit grayscale png Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List > What I am trying to do (if you haven't guessed) is DICOM 16-bit gray that > will display on a browser as such (without plug-ins or client side code) png > was chosen because it can do 16-g and it's lossless. I haven't been following this discussion very closely, but it seems to me that there are at least a couple of misunderstandings here: - Unless you've paid several thousand dollars, you almost certainly don't have a frame buffer and monitor that are capable of displaying more than 8 bits of intensity. Certainly there's no point in browsers retaining the lower 8 bits, because there are virtually no GUIs in existence that support more than that. (X is probably an exception, but it's still dependent on appropriate hardware, which is exceedingly rare.) - If I recall correctly, your "16-bit" data was actually more like 12-bit, packed into the *least* significant bits of each word. Ac- cording to the PNG spec, those are dark gray--period. If you want the full intensity range to be displayed, *you* are required to scale the gray values to a maxval of 65536 before storing them in PNG format. (You can include an sBIT chunk if you wish to indicate the number of significant bits for later rescaling.) In short, while there are undoubtedly broken PNG viewers out there, I don't think your problems are (completely) due to them. Btw, if I recall correctly, http://www.libpng.org/pub/png/pngvrml/ct2.9-128x128.png was converted from a raw medical scan (and scaled). It displays just fine in browsers, aside from the transparency. Greg -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sat Aug 4 23:55:08 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id XAA07642 for ; Sat, 4 Aug 2001 23:55:08 -0500 (CDT) Received: by webshld.ccf.swri.edu; id XAA16426; Sat, 4 Aug 2001 23:53:23 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAIVaifG; Sat, 4 Aug 01 23:53:22 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f754mON26705 for ; Sat, 4 Aug 2001 23:48:24 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f754sqE07002; Sat, 4 Aug 2001 23:54:52 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from linux1.anark.com (linux1.anark.com [216.17.159.252]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f754sp506998 for ; Sat, 4 Aug 2001 23:54:51 -0500 (CDT) Received: from MFORNANDER (station213.anark.com [216.17.159.213]) by linux1.anark.com (8.11.1/8.11.1) with SMTP id f754t1920229 for ; Sat, 4 Aug 2001 22:55:01 -0600 From: "Mattias Fornander" To: Subject: RE: Slim PNG implementation? Date: Sat, 4 Aug 2001 22:55:01 -0600 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 In-Reply-To: Importance: Normal Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Hi all, I've successfully integrated PNG into my stream and I'm crunching my 32-bit images but I'm jelaous of the sizes pngcrush is getting. I would like for the user to be able to go into a lossy mode where he/she can select how many colors should be available. The source image will always be 32-bit and the destination will be 32-bit but will be quantized (but not dithered) if the total number of user colors is less than 256 (255 if alpha is used). Since I'm compressing to a stream I have a hard time testing the format of output images I produce so I have these questions: 1. Can LibPNG automatically reduce 32/24bit images to palettized PNG files? 2. Do I have to convert the 32bit input and output data manually or does png_set_packing/png_set_expand take care of that? i.e. I would like to compress from RGBA and to RGBA through a palette PNG file. Is there an easy way? 3. What are the IDAT methods that pngcrush uses to further compress PNG files? 4. Is the palette RGB or RGBA? Meaning can I have a palettelized image with 8bit alpha? Thank you! Mattias -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sun Aug 5 01:00:08 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id BAA07826 for ; Sun, 5 Aug 2001 01:00:08 -0500 (CDT) Received: by webshld.ccf.swri.edu; id AAA17681; Sun, 5 Aug 2001 00:58:23 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAgbaqHI; Sun, 5 Aug 01 00:58:23 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f755rON27785 for ; Sun, 5 Aug 2001 00:53:24 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f755xvG07459; Sun, 5 Aug 2001 00:59:57 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from genesis.tmfi.com ([199.103.206.10]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f755xu507455 for ; Sun, 5 Aug 2001 00:59:56 -0500 (CDT) Received: from sanjuan ([208.192.101.8]) by genesis.tmfi.com with Microsoft SMTPSVC(5.0.2195.2966); Sun, 5 Aug 2001 01:24:42 -0400 From: "Carlos Rodriguez" To: "PNG Implementation List" Subject: RE: writing a 16 bit grayscale png Date: Sun, 5 Aug 2001 01:24:42 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) x-mimeole: Produced By Microsoft MimeOLE V5.00.3018.1300 Importance: Normal In-Reply-To: <200108050437.f754bqn22085@sonic.net> X-OriginalArrivalTime: 05 Aug 2001 05:24:43.0367 (UTC) FILETIME=[EED59F70:01C11D6E] Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Greg: Of course I understand that hardly any commercial frame buffers (or monitors) out there are going to have DACs that can handle more than 255 steps. I just misunderstood how viewers handled 16-bit data. I *thought* they would, by default, convert to 24bit color to DISPLAY. Like I said, I am a newbie.And I apologize for the murky code which was in fact 12 bit and pretty dark, but I fixed that later (I never sent that code, but I did scale up to 0xffff). I understand none of my problems are due to broken png viewers. I know there are limitations inherent in the display hardware. Rich's pseudo-gray is one way to get around that. And, for the record, the way I do things now is in fact scaling the DICOM images down to 8-bits. And to me they look great. But this is (sadly) not my call to make. They want 2^12 gray levels and by god I'm gonna give it to them (somehow). So if I offended anyone by deriding the viewer software I apologize (I've written a few myself and they ain't that slick). BTW, some of these people I'm writing this for are used to multi-thousand dollar video cards and monitors which can (I'm told) display these many grays. In short, thank you for your attention. I think I'm on track now, and thanks for your help so far and in the future. -Carlos Rodriguez "Running his mouth about things he doesn't understand since 1974" -----Original Message----- From: owner-png-implement@ccrc.wustl.edu [mailto:owner-png-implement@ccrc.wustl.edu]On Behalf Of Greg Roelofs Sent: Sunday, August 05, 2001 12:38 AM To: png-implement@ccrc.wustl.edu Subject: RE: writing a 16 bit grayscale png > What I am trying to do (if you haven't guessed) is DICOM 16-bit gray that > will display on a browser as such (without plug-ins or client side code) png > was chosen because it can do 16-g and it's lossless. I haven't been following this discussion very closely, but it seems to me that there are at least a couple of misunderstandings here: - Unless you've paid several thousand dollars, you almost certainly don't have a frame buffer and monitor that are capable of displaying more than 8 bits of intensity. Certainly there's no point in browsers retaining the lower 8 bits, because there are virtually no GUIs in existence that support more than that. (X is probably an exception, but it's still dependent on appropriate hardware, which is exceedingly rare.) - If I recall correctly, your "16-bit" data was actually more like 12-bit, packed into the *least* significant bits of each word. Ac- cording to the PNG spec, those are dark gray--period. If you want the full intensity range to be displayed, *you* are required to scale the gray values to a maxval of 65536 before storing them in PNG format. (You can include an sBIT chunk if you wish to indicate the number of significant bits for later rescaling.) In short, while there are undoubtedly broken PNG viewers out there, I don't think your problems are (completely) due to them. Btw, if I recall correctly, http://www.libpng.org/pub/png/pngvrml/ct2.9-128x128.png was converted from a raw medical scan (and scaled). It displays just fine in browsers, aside from the transparency. Greg -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sun Aug 5 01:53:47 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id BAA08052 for ; Sun, 5 Aug 2001 01:53:46 -0500 (CDT) Received: by webshld.ccf.swri.edu; id BAA18665; Sun, 5 Aug 2001 01:52:01 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAHIaaDK; Sun, 5 Aug 01 01:52:00 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f756krN28673 for ; Sun, 5 Aug 2001 01:47:00 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f756rVA07840; Sun, 5 Aug 2001 01:53:31 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f756rU507836 for ; Sun, 5 Aug 2001 01:53:30 -0500 (CDT) Received: from indus.ecliptic (24.67.95.214) by mail.san.yahoo.com (5.5.039.2) id 3B6B1F4600037782 for png-implement@ccrc.wustl.edu; Sat, 4 Aug 2001 23:52:30 -0700 Message-Id: <3.0.3.32.20010805005409.0075dfb4@mail.schaik.com> X-Sender: willemschaik@mail.schaik.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Date: Sun, 05 Aug 2001 00:54:09 -0600 To: PNG Implementation List From: Willem van Schaik Subject: Re: Efficient generation of png images In-Reply-To: <200108021443.f72Ehfn16970@sonic.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 07:43 02-08-2001 -0700, Greg wrote: >See http://gnuwin32.sourceforge.net/packages.html , specifically the >"NetPbm" link. A version of pnmtopng is included in that (at least in >9.15; I'm pretty sure 9.14, too). And there may already be a new-NetPBM >port to Cygwin, but I happened to come across this one a couple of days >ago. Have a look at SourceForge bug-report #448084, which I submitted tonight. In short, it looks like all output (and input ?) files are opened in text-mode instead of binary. Which for Unix doesn't matter, but for DOS is fatal. Result is that all ppm's generated are corrupt, but the same is true for programs like ppmtogif, etc. So, also the pnmtopng.exe in the gnuwin32 - netpbm package is corrupt!! Willem -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sun Aug 5 06:08:22 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id GAA08978 for ; Sun, 5 Aug 2001 06:08:22 -0500 (CDT) Received: by webshld.ccf.swri.edu; id GAA23467; Sun, 5 Aug 2001 06:06:37 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAATdaq1T; Sun, 5 Aug 01 06:06:36 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f75B1dN02861 for ; Sun, 5 Aug 2001 06:01:39 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f75B85H09669; Sun, 5 Aug 2001 06:08:05 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail12.sdc1.sfba.home.com (femail12.sdc1.sfba.home.com [24.0.95.108]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f75B84509665 for ; Sun, 5 Aug 2001 06:08:04 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail12.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010805110801.PBQY19709.femail12.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com> for ; Sun, 5 Aug 2001 04:08:01 -0700 Message-Id: <3.0.6.32.20010805070542.00e1b290@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Sun, 05 Aug 2001 07:05:42 -0400 To: PNG Implementation List From: Glenn Randers-Pehrson Subject: RE: Slim PNG implementation? In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 10:55 PM 8/4/01 -0600, Mattias Fornander wrote: >1. Can LibPNG automatically reduce 32/24bit images to palettized PNG files? No, your application must build the palette. >2. Do I have to convert the 32bit input and output data manually or does >png_set_packing/png_set_expand take care of that? i.e. I would like to >compress from RGBA and to RGBA through a palette PNG file. Is there an easy >way? png_set_packing takes care of sub-8-bit depths but does not switch between color types. >3. What are the IDAT methods that pngcrush uses to further compress PNG >files? Various standard PNG filters with various zlib strategies and levels. >4. Is the palette RGB or RGBA? Meaning can I have a palettelized image with >8bit alpha? RGBA. It is conveyed in two chunks; PLTE for the RGB components and tRNS for the alpha component. You are limited to 256 different RGBA combinations. Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sun Aug 5 09:21:23 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id JAA09443 for ; Sun, 5 Aug 2001 09:21:23 -0500 (CDT) Received: by webshld.ccf.swri.edu; id JAA27494; Sun, 5 Aug 2001 09:19:37 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAhwaOS1; Sun, 5 Aug 01 09:19:37 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f75EEdN06252 for ; Sun, 5 Aug 2001 09:14:39 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f75EJmx11107; Sun, 5 Aug 2001 09:19:48 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail22.bigmailbox.com (mail22.bigmailbox.com [209.132.220.199]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f75EJk511103 for ; Sun, 5 Aug 2001 09:19:47 -0500 (CDT) Received: by mail22.bigmailbox.com (8.8.7/8.8.7) id HAA09876; Sun, 5 Aug 2001 07:19:49 -0700 Date: Sun, 5 Aug 2001 07:19:49 -0700 Message-Id: <200108051419.HAA09876@mail22.bigmailbox.com> Content-Type: text/plain Content-Disposition: inline Content-Transfer-Encoding: binary X-Mailer: MIME-tools 4.104 (Entity 4.116) Mime-Version: 1.0 X-Originating-Ip: [65.33.98.177] From: "Rich Franzen" To: png-implement@ccrc.wustl.edu Subject: Re: Efficient generation of png images Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Willem, Thanks for the "heads up"! Are you doing the port to win32 ? The stupid O_BINARY thing bit me a couple weeks ago on a work-related project. I'm used to Unix-think, and the thought the OS would even try to mess with your data before you get to it (and after) is a foreign concept. I know it's way too late to change now, but the logic is backwards. The flag shouldn't be O_BINARY, it should be O_TEXT (or, in fopen(), "t" instead of "b"). You should have to specifically instruct the OS to cook your data, not prevent it from doing so. Anyone programming with CygWin, here's a related alert. Leaving out the O_BINARY will not be a problem when the executable runs on win95 or win98. But if that same executable with the same cygwin1.dll is ran on an NT machine, the code will treat the open as a text-mode open. Solution: include O_BINARY in your open(). Then the code executates properly on both platforms. Doh! What am I thinking?! This must be one of those wonderful Microsoft innovations they want the right to propogate! ;) (Hey I know it probably predates Microsoft, probably back to cp/m or before. Punchcard - Not Punchcard. But it's still a pain in the a**.) -- Rich --- http://rocq.home.att.net >Date: Sun, 05 Aug 2001 00:54:09 -0600 > PNG Implementation List Willem van Schaik Re: Efficient generation of png imagesReply-To: PNG Implementation List > >At 07:43 02-08-2001 -0700, Greg wrote: > >>See http://gnuwin32.sourceforge.net/packages.html , specifically the >>"NetPbm" link. A version of pnmtopng is included in that (at least in >>9.15; I'm pretty sure 9.14, too). And there may already be a new-NetPBM >>port to Cygwin, but I happened to come across this one a couple of days >>ago. > >Have a look at SourceForge bug-report #448084, which I submitted tonight. >In short, it looks like all output (and input ?) files are opened in >text-mode instead of binary. Which for Unix doesn't matter, but for DOS is >fatal. Result is that all ppm's generated are corrupt, but the same is true >for programs like ppmtogif, etc. > >So, also the pnmtopng.exe in the gnuwin32 - netpbm package is corrupt!! > >Willem ------------------------------------------------------------ --== Sent via Deja.com ==-- http://www.deja.com/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sun Aug 5 10:49:09 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id KAA09662 for ; Sun, 5 Aug 2001 10:49:09 -0500 (CDT) Received: by webshld.ccf.swri.edu; id KAA29606; Sun, 5 Aug 2001 10:47:24 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAEkaO05; Sun, 5 Aug 01 10:47:23 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f75FgPN07924 for ; Sun, 5 Aug 2001 10:42:26 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f75Fmsv11803; Sun, 5 Aug 2001 10:48:54 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail25.bigmailbox.com (mail25.bigmailbox.com [209.132.220.211]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f75Fmr511799 for ; Sun, 5 Aug 2001 10:48:53 -0500 (CDT) Received: by mail25.bigmailbox.com (8.8.7/8.8.7) id IAA25374; Sun, 5 Aug 2001 08:48:57 -0700 Date: Sun, 5 Aug 2001 08:48:57 -0700 Message-Id: <200108051548.IAA25374@mail25.bigmailbox.com> Content-Type: text/plain Content-Disposition: inline Content-Transfer-Encoding: binary X-Mailer: MIME-tools 4.104 (Entity 4.116) Mime-Version: 1.0 X-Originating-Ip: [65.33.98.177] From: "Rich Franzen" To: png-implement@ccrc.wustl.edu Subject: RE: writing a 16 bit grayscale png Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Carlos, I don't believe Greg was criticizing you at all. He admits to missing part of the conversation, and did the best he could to be helpful. Many who read this probably haven't had the opportunity to work with deep grey. There are several issues which arise that don't affect the 8-bitters. "Chopping off the low order bits" may seem like a practical solution, and if the _only_ issue is display of a static image, then the chopping block is indeed workable. Even then there is a better way, and the PNG guidelines suggest it. Don't chop. Ratio. I.e., in the case of a 16-bit image, multiply by the ratio "(256 - 1) / (65536 - 1)". (It simplifies to dividing by exactly 257.) What's the difference? Infinity. 65535 is not a normal brightness value. It also represents saturation; all brightnesses greater than or equal to 65535 map to 65535. They could not be digitized because the ADC and digital electronics can't handle anything larger. A value of 65530 is not saturated. Dropping the low order byte results in all values between 65280 and 65535 being treated as "infinite", when only 65535 has that distinction. Analysts of 12- or 16-bit imagery typically have control of the mapping to the frame-buffer's bit-depth. They may have control of contrast, brightness, and a non-linear function such as gamma. This gives them the ability to enhance, for example, the dark regions of the x-ray. PhotoShop and other programs allow for the same sort of enhancements. However, if they pre-crop the image to 8 bits before analysis is done, a huge loss of information occurs. The original film is very sensitive in recording low changes in energy levels. Doctors and NDT (non-destructive testing) analysts want to see what the film caught, not what PhotoShop finds convenient to work with. There are commercial programs which preserve the integrity of the image as it is being analyzed. And as I've mentioned before, ImageMagick can be compiled to do so as well. Carlos (back to you), depending on how your images will be used, pseudogrey may NOT be the way to go. If you are simply displaying pre-stretched, static imagery, then pseudogrey would be the best way to display it. But if you need to preserve what the scanner caught, then keeping the image in its 16-bit PNG form is probably the appropriate solution. Even a 12-bit scanner has 4096 levels, and pseudogrey would reduce these to 1786. It's better than 8-bit (10-bit even) but not as good as 12. -- Rich (foot-in-mouth disease since 1964 ;) --- http://rocq.home.att.net > "Carlos Rodriguez" "PNG Implementation List" RE: writing a 16 bit grayscale pngDate: Sun, 5 Aug 2001 01:24:42 -0400 >Reply-To: PNG Implementation List > >Greg: > >Of course I understand that hardly any commercial frame buffers (or >monitors) out there are going to have DACs that can handle more than 255 >steps. I just misunderstood how viewers handled 16-bit data. I *thought* >they would, by default, convert to 24bit color to DISPLAY. Like I said, I am >a newbie.And I apologize for the murky code which was in fact 12 bit and >pretty dark, but I fixed that later (I never sent that code, but I did scale >up to 0xffff). > >I understand none of my problems are due to broken png viewers. I know >there are limitations inherent in the display hardware. Rich's pseudo-gray >is one way to get around that. And, for the record, the way I do things now >is in fact scaling the DICOM images down to 8-bits. And to me they look >great. But this is (sadly) not my call to make. They want 2^12 gray levels >and by god I'm gonna give it to them (somehow). So if I offended anyone by >deriding the viewer software I apologize (I've written a few myself and they >ain't that slick). > >BTW, some of these people I'm writing this for are used to multi-thousand >dollar video cards and monitors which can (I'm told) display these many >grays. > >In short, thank you for your attention. I think I'm on track now, and >thanks for your help so far and in the future. > >-Carlos Rodriguez >"Running his mouth about things he doesn't understand since 1974" ------------------------------------------------------------ --== Sent via Deja.com ==-- http://www.deja.com/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sun Aug 5 20:18:36 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id UAA10933 for ; Sun, 5 Aug 2001 20:18:34 -0500 (CDT) Received: by webshld.ccf.swri.edu; id UAA14144; Sun, 5 Aug 2001 20:16:48 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAAha4NB; Sun, 5 Aug 01 20:16:48 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f761BnN19088 for ; Sun, 5 Aug 2001 20:11:49 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f761GsS16187; Sun, 5 Aug 2001 20:16:54 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f761Gr516183 for ; Sun, 5 Aug 2001 20:16:53 -0500 (CDT) Received: (qmail 28535 invoked from network); 6 Aug 2001 01:17:00 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 6 Aug 2001 01:17:00 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f761EvF31750 for png-implement@ccrc.wustl.edu; Sun, 5 Aug 2001 18:14:57 -0700 Date: Sun, 5 Aug 2001 18:14:57 -0700 Message-Id: <200108060114.f761EvF31750@sonic.net> From: Greg Roelofs To: png-implement@ccrc.wustl.edu Subject: RE: writing a 16 bit grayscale png Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Hi, Carlos, > Of course I understand that hardly any commercial frame buffers (or > monitors) out there are going to have DACs that can handle more than 255 > steps. I just misunderstood how viewers handled 16-bit data. I *thought* > they would, by default, convert to 24bit color to DISPLAY. Well, they do, assuming the output display depth is 24 bits. But in the case of grayscale, that means truncating 16 bits to 8 and then replicating it across the R, G and B channels. (Perhaps the misunderstanding was with what PC operating systems call "16-bit" displays? Those 16 bits are used for all three color channels--typically 5, 6 and 5 bits, respectively--and are completely unrelated to 16-bit grayscale unless you're willing to put up with a pseudocolor rendering of your grayscale data.) > I understand none of my problems are due to broken png viewers. I know > there are limitations inherent in the display hardware. Rich's pseudo-gray > is one way to get around that. And, for the record, the way I do things now > is in fact scaling the DICOM images down to 8-bits. And to me they look > great. But this is (sadly) not my call to make. They want 2^12 gray levels > and by god I'm gonna give it to them (somehow). So if I offended anyone by > deriding the viewer software I apologize (I've written a few myself and they > ain't that slick). As Rich said, there's no issue of offense. But "wanting 2^12 gray levels" ain't going to happen, assuming we're talking about standard PCs or work- stations and standard browsers. The 16-bit grayscale PNG images will *have* all 2^12 gray levels, scaled (preferably) or otherwise, but they won't dis- play as such on anything but specialized hardware using specialized software. (Or you can write custom software that dynamically remaps the 12-bit gray levels to different 8-bit gray ranges or to different 24-bit color gradients; but that's a fairly specialized function usually only found in scientific software.) > BTW, some of these people I'm writing this for are used to multi-thousand > dollar video cards and monitors which can (I'm told) display these many > grays. Then the only issue is whether their software can read PNGs natively, or whether it needs some sort of external conversion (e.g., pngtopnm) first. Btw, there's a "dicom2" program listed on the PNG converters page, I think. Regards, Greg -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sun Aug 5 22:40:32 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id WAA11221 for ; Sun, 5 Aug 2001 22:40:32 -0500 (CDT) Received: by webshld.ccf.swri.edu; id WAA17571; Sun, 5 Aug 2001 22:38:46 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAiUaquI; Sun, 5 Aug 01 22:38:46 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f763XmN21753 for ; Sun, 5 Aug 2001 22:33:49 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f763eE417255; Sun, 5 Aug 2001 22:40:14 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f763eD517251 for ; Sun, 5 Aug 2001 22:40:13 -0500 (CDT) Received: (qmail 7080 invoked from network); 6 Aug 2001 03:40:21 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 6 Aug 2001 03:40:21 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f763cJb19992 for png-implement@ccrc.wustl.edu; Sun, 5 Aug 2001 20:38:19 -0700 Date: Sun, 5 Aug 2001 20:38:19 -0700 Message-Id: <200108060338.f763cJb19992@sonic.net> From: Greg Roelofs To: png-implement@ccrc.wustl.edu Subject: Re: Efficient generation of png images Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Rich wrote: > > Doh! What am I thinking?! This must be one of those wonderful > Microsoft innovations they want the right to propogate! ;) > (Hey I know it probably predates Microsoft, probably back to cp/m or > before. Punchcard - Not Punchcard. But it's still a pain in the a**.) > I believe it is documented in K&R, at least the 2nd edition... And it doesn't hurt any system to use the "b" modifier for binary files, so it's a good habit to get into. Note that some buggy compilers and/or OSes require both fopen() with "b" and setmode() in order to make stdin/stdout binary. *That's* bogus. Greg -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sun Aug 5 22:54:47 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id WAA11301 for ; Sun, 5 Aug 2001 22:54:46 -0500 (CDT) Received: by webshld.ccf.swri.edu; id WAA17886; Sun, 5 Aug 2001 22:53:01 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAvpaO7I; Sun, 5 Aug 01 22:53:00 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f763m2N22002 for ; Sun, 5 Aug 2001 22:48:03 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f763sX517364; Sun, 5 Aug 2001 22:54:33 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from genesis.tmfi.com ([199.103.206.10]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f763sW517360 for ; Sun, 5 Aug 2001 22:54:33 -0500 (CDT) Received: from sanjuan ([208.192.102.82]) by genesis.tmfi.com with Microsoft SMTPSVC(5.0.2195.2966); Sun, 5 Aug 2001 23:53:14 -0400 From: "Carlos Rodriguez" To: "PNG Implementation List" Subject: RE: writing a 16 bit grayscale png Date: Sun, 5 Aug 2001 23:53:13 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) In-Reply-To: <200108060114.f761EvF31750@sonic.net> x-mimeole: Produced By Microsoft MimeOLE V5.00.3018.1300 Importance: Normal X-OriginalArrivalTime: 06 Aug 2001 03:53:15.0326 (UTC) FILETIME=[521EC5E0:01C11E2B] Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Hi Greg: Thanks for your reply. >(Or you can write custom software that dynamically remaps the 12-bit gray >levels to different 8-bit gray ranges or to different 24-bit color gradients; >but that's a fairly specialized function usually only found in scientific >software.) That's actually what I thought I was going to have to do : write a 2^12 LUT funtion in which each grayscale index would correspond to some idealized RGB triple. BUt I think it's best if we just leave the 16-bit gs values in place and let the viewer scale to 8-bits (not truncate). That way I can implement window-leveling better. BTW, this has drifted a tad (hehehe) off-topic, for which I apologize. Thanks to everyone who responded -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Mon Aug 6 00:47:56 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id AAA11672 for ; Mon, 6 Aug 2001 00:47:56 -0500 (CDT) Received: by webshld.ccf.swri.edu; id AAA22088; Mon, 6 Aug 2001 00:46:10 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA76a4iR; Mon, 6 Aug 01 00:46:10 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f765fCN24753 for ; Mon, 6 Aug 2001 00:41:12 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f765lj618231; Mon, 6 Aug 2001 00:47:45 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f765li518227 for ; Mon, 6 Aug 2001 00:47:44 -0500 (CDT) Received: from volans (24.67.95.214) by mail.san.yahoo.com (5.5.039.2) id 3B6B1F4600061839 for png-implement@ccrc.wustl.edu; Sun, 5 Aug 2001 22:46:49 -0700 Message-Id: <3.0.3.32.20010805234747.00731d64@mail.schaik.com> X-Sender: willemschaik@mail.schaik.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Date: Sun, 05 Aug 2001 23:47:47 -0600 To: PNG Implementation List From: Willem van Schaik Subject: RE: Slim PNG implementation? In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 22:55 04-08-01 -0600, Mattias wrote: > >I would like for the user to be able to go into a lossy mode where he/she >can select how many colors should be available. The source image will >always be 32-bit and the destination will be 32-bit but will be quantized >(but not dithered) if the total number of user colors is less than 256 (255 >if alpha is used). Pnmtopng is doing exactly that. So you could either pipe your output to that filter, or grap the source code and include it into your own software. Willem -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Mon Aug 6 03:57:56 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id DAA12361 for ; Mon, 6 Aug 2001 03:57:56 -0500 (CDT) Received: by webshld.ccf.swri.edu; id DAA28411; Mon, 6 Aug 2001 03:56:10 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA4KaqF3; Mon, 6 Aug 01 03:56:04 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f768p0N29285 for ; Mon, 6 Aug 2001 03:51:05 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f768tua19708; Mon, 6 Aug 2001 03:55:56 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from infonegocio.com ([195.235.35.107]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f768tt519704 for ; Mon, 6 Aug 2001 03:55:55 -0500 (CDT) Received: from MM2000 ([213.97.41.5]) by infonegocio.com with Microsoft SMTPSVC(5.5.1877.507.50); Mon, 6 Aug 2001 10:52:40 +0200 Message-ID: <003601c11e82$39ef7260$02001aac@MM2000> From: =?iso-8859-1?Q?Mart=ED_Maria?= To: "PNG Implementation List" References: <200108060114.f761EvF31750@sonic.net> Subject: Re: writing a 16 bit grayscale png Date: Mon, 6 Aug 2001 10:55:10 -0320 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Hi, > As Rich said, there's no issue of offense. But "wanting 2^12 gray levels" > ain't going to happen, assuming we're talking about standard PCs or work- > stations and standard browsers. The 16-bit grayscale PNG images will *have* > all 2^12 gray levels, scaled (preferably) or otherwise, but they won't dis- > play as such on anything but specialized hardware using specialized software. > (Or you can write custom software that dynamically remaps the 12-bit gray > levels to different 8-bit gray ranges or to different 24-bit color gradients; > but that's a fairly specialized function usually only found in scientific > software.) One solution could be to use an icc profile. This would be a standard way, and suitable for many color-enabled apps. However, on depending on viewing condition, 12 bit gray scale are below the "just noticeable difference" and cannot be seen anyway. But if you are going to this detail, you should take the in account characteristics of the device as well. Regards, Martí Maria The little cms project http://www.littlecms.com marti@littlecms.com -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 8 00:11:05 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id AAA28326 for ; Wed, 8 Aug 2001 00:11:05 -0500 (CDT) Received: by webshld.ccf.swri.edu; id AAA20992; Wed, 8 Aug 2001 00:09:17 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAR7a4_O; Wed, 8 Aug 01 00:09:16 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7854GY22219 for ; Wed, 8 Aug 2001 00:04:16 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7859NB26726; Wed, 8 Aug 2001 00:09:23 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f7859Ld26722 for ; Wed, 8 Aug 2001 00:09:21 -0500 (CDT) Received: (qmail 28913 invoked from network); 8 Aug 2001 05:09:15 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 8 Aug 2001 05:09:15 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f78578F32095 for png-implement@ccrc.wustl.edu; Tue, 7 Aug 2001 22:07:08 -0700 Received: from odd.local (BSN-62-93.dsl.siol.net [213.250.62.93]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f77GT1d16555 for ; Tue, 7 Aug 2001 11:29:02 -0500 (CDT) Received: from jebacch ([192.168.0.10]) by odd.local with Microsoft SMTPSVC(5.0.2195.2966); Tue, 7 Aug 2001 18:29:00 +0200 From: "Iztok Stotl" To: Subject: png bug Date: Tue, 7 Aug 2001 18:25:39 +0200 Message-ID: <000001c11f5d$98b801a0$0a00a8c0@odd.local> X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.2616 Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 X-OriginalArrivalTime: 07 Aug 2001 16:29:00.0323 (UTC) FILETIME=[1041F730:01C11F5E] Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List [non-member submission; HTML removed] I saw the page ;)) http://www.libpng.org/pub/png/png-MagnoliaAlpha.html I realy like the magnolia picture. Why doesn't my picture transparency work with mozilla 0.93, but works well wit netscape 6.01 and IE ? https://down.krneki.org ... the picture of the storch shouldn't have only white background ;)) Messner -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 8 09:37:34 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id JAA01145 for ; Wed, 8 Aug 2001 09:37:33 -0500 (CDT) Received: by webshld.ccf.swri.edu; id JAA01294; Wed, 8 Aug 2001 09:35:45 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAANkaOEc; Wed, 8 Aug 01 09:35:42 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f78EUgY12129 for ; Wed, 8 Aug 2001 09:30:42 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f78Eb1801715; Wed, 8 Aug 2001 09:37:01 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail12.sdc1.sfba.home.com (femail12.sdc1.sfba.home.com [24.0.95.108]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f78Eaxd01711 for ; Wed, 8 Aug 2001 09:37:00 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail12.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010808143659.GKZI19709.femail12.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com>; Wed, 8 Aug 2001 07:36:59 -0700 Message-Id: <3.0.6.32.20010808103447.00f8c6a0@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Wed, 08 Aug 2001 10:34:47 -0400 To: PNG Implementation List From: Glenn Randers-Pehrson Subject: Re: bug in netpbm 9.14 or libpng 1.0.10? Cc: bryanh@giraffe-data.com, gaius@glam.ac.uk, wl@gnu.org In-Reply-To: <3.0.6.32.20010723080005.00e3d160@netmail.home.com> References: <200107211820.f6LIKtM18223@sonic.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 08:00 AM 7/23/01 -0400, Glenn Randers-Pehrson wrote: >At 11:20 AM 7/21/01 -0700, Greg Roelofs wrote: > >>It's a bug in 2.37.5. > >Libpng should, however, have caught the mistake and refused to write >the erroneous bKGD chunk. A similar situation, which I'll fix, pertains to the tRNS chunk. The current libpng version is willing to write out-of-range color values. Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 8 10:03:04 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id KAA01405 for ; Wed, 8 Aug 2001 10:03:04 -0500 (CDT) Received: by webshld.ccf.swri.edu; id KAA06233; Wed, 8 Aug 2001 10:01:16 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAqDaaim; Wed, 8 Aug 01 10:01:07 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f78Eu7Y13673 for ; Wed, 8 Aug 2001 09:56:07 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f78F2ic02213; Wed, 8 Aug 2001 10:02:44 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from hermes.med-web.com (mail.med-web.com [207.175.164.123]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f78F2hd02209 for ; Wed, 8 Aug 2001 10:02:43 -0500 (CDT) Received: from med-web.com (eris.med-web.com [192.168.240.23]) by hermes.med-web.com (8.9.3/8.9.3) with ESMTP id KAA08465; Wed, 8 Aug 2001 10:02:42 -0500 Message-ID: <3B715492.7F2A8051@med-web.com> Date: Wed, 08 Aug 2001 10:02:42 -0500 From: Jason Summers X-Mailer: Mozilla 4.75 [en] (Win95; U) X-Accept-Language: en MIME-Version: 1.0 To: PNG Implementation List CC: stotl@mf.uni-lj.si Subject: Re: png bug References: <000001c11f5d$98b801a0$0a00a8c0@odd.local> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Iztok Stotl wrote: > > Why doesn't my picture transparency work with mozilla 0.93, but works > well wit netscape 6.01 and IE ? > > ... the picture of > the storch shouldn't have only white background ;)) > > Messner Your image is fine; it's a bug in Mozilla. Alpha transparency works, but not binary transparency. Only in Mozilla could such a ridiculous bug exist. See http://bugzilla.mozilla.org/show_bug.cgi?id=84980 (note that the first explanation on that page is not very accurate) and http://entropymine.com/jason/testbed/pngtrans/ -- Jason Summers -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 8 11:51:07 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id LAA02404 for ; Wed, 8 Aug 2001 11:51:07 -0500 (CDT) Received: by webshld.ccf.swri.edu; id LAA25127; Wed, 8 Aug 2001 11:49:19 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAnqaWeX; Wed, 8 Aug 01 11:49:18 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f78GiIY20104 for ; Wed, 8 Aug 2001 11:44:18 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f78Gont04216; Wed, 8 Aug 2001 11:50:49 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from chef.ecs.soton.ac.uk (chef.ecs.soton.ac.uk [152.78.65.102]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f78Gomd04211 for ; Wed, 8 Aug 2001 11:50:48 -0500 (CDT) Received: (from njl98r@localhost) by chef.ecs.soton.ac.uk (8.11.2/8.11.2) id f78GopF00634 for png-implement@ccrc.wustl.edu; Wed, 8 Aug 2001 17:50:51 +0100 Date: Wed, 8 Aug 2001 17:50:51 +0100 From: Nick Lamb To: PNG Implementation List Subject: Re: png bug Message-ID: <20010808175051.A30862@ecs.soton.ac.uk> Mail-Followup-To: PNG Implementation List References: <000001c11f5d$98b801a0$0a00a8c0@odd.local> <3B715492.7F2A8051@med-web.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <3B715492.7F2A8051@med-web.com>; from jason@med-web.com on Wed, Aug 08, 2001 at 10:02:42AM -0500 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List On Wed, Aug 08, 2001 at 10:02:42AM -0500, Jason Summers wrote: > and http://entropymine.com/jason/testbed/pngtrans/ Wow, that's much better than mine. What are your feelings about linking to it/ copying it (with credit) in its entirety? BTW The Win32-binary-transparency bug is an old classic. Probably just poking the people who solved it last time would be a good start to getting it fixed in 0.9.x Nick. -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 8 14:52:17 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id OAA04109 for ; Wed, 8 Aug 2001 14:52:16 -0500 (CDT) Received: by webshld.ccf.swri.edu; id OAA23435; Wed, 8 Aug 2001 14:50:28 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA__aaXT; Wed, 8 Aug 01 14:50:28 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f78JjRY00515 for ; Wed, 8 Aug 2001 14:45:27 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f78JpZ201213; Wed, 8 Aug 2001 14:51:35 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail15.sdc1.sfba.home.com (femail15.sdc1.sfba.home.com [24.0.95.142]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f78JpX401209 for ; Wed, 8 Aug 2001 14:51:34 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail15.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010808195139.HXRS21777.femail15.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com> for ; Wed, 8 Aug 2001 12:51:39 -0700 Message-Id: <3.0.6.32.20010808154919.00e2fcf0@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Wed, 08 Aug 2001 15:49:19 -0400 To: png-implement@ccrc.wustl.edu From: Glenn Randers-Pehrson Subject: libpng-1.2.0beta5 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Libpng-1.2.0beta5 is available for download from http://libpng.sf.net/ and from ftp://swrinde.nde.swri.edu/pub/png-group/src/ Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 9 02:24:15 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id CAA07401 for ; Thu, 9 Aug 2001 02:24:14 -0500 (CDT) Received: by webshld.ccf.swri.edu; id CAA16497; Thu, 9 Aug 2001 02:22:25 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAHIa4nG; Thu, 9 Aug 01 02:22:23 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f797HNY27307 for ; Thu, 9 Aug 2001 02:17:23 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f797I1v08019; Thu, 9 Aug 2001 02:18:01 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from linux1.anark.com (linux1.anark.com [216.17.159.252]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f797Hx408015 for ; Thu, 9 Aug 2001 02:17:59 -0500 (CDT) Received: from MFORNANDER (station213.anark.com [216.17.159.213]) by linux1.anark.com (8.11.1/8.11.1) with SMTP id f797Hq916143 for ; Thu, 9 Aug 2001 01:18:00 -0600 From: "Mattias Fornander" To: Subject: Legal transformations? Date: Thu, 9 Aug 2001 01:17:52 -0600 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List First of all, thanks for the great responses I've gotten! Question: If I want every kind of PNG file I get to decompress into an RGBA buffer with 4 bytes for every pixels, can I simply set all the transformation bits or do I have to analyze the colortype and bitdepth before I use them? Another way of phrasing it would be: Is there a set of png_set_XXX methods I can call before unpacking to ensure that all PNG files are unpacked to an 8bit RGBA buffer? Thank you in advance! Mattias -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 9 08:17:18 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id IAA08921 for ; Thu, 9 Aug 2001 08:17:18 -0500 (CDT) Received: by webshld.ccf.swri.edu; id IAA03897; Thu, 9 Aug 2001 08:15:29 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAn1aaNh; Thu, 9 Aug 01 08:15:28 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f79DASY07980 for ; Thu, 9 Aug 2001 08:10:28 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f79DGpB10787; Thu, 9 Aug 2001 08:16:51 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f79DGp410783 for ; Thu, 9 Aug 2001 08:16:51 -0500 (CDT) Received: from volans (129.37.161.106) by mail.san.yahoo.com (5.5.041.1) id 3B708CF70004863B for png-implement@ccrc.wustl.edu; Thu, 9 Aug 2001 06:15:51 -0700 Message-Id: <3.0.3.32.20010809071641.00733634@mail.schaik.com> X-Sender: willemschaik@mail.schaik.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Date: Thu, 09 Aug 2001 07:16:41 -0600 To: PNG Implementation List From: Willem van Schaik Subject: Re: Legal transformations? In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List >Question from Mattias: >If I want every kind of PNG file I get to decompress into an RGBA buffer >with 4 bytes for every pixels, can I simply set all the transformation bits >or do I have to analyze the colortype and bitdepth before I use them? > Answer from Willem: I often use the following piece of code to convert any PNG into 4x8: ---- // read all PNG info up to image data png_read_info(png_ptr, info_ptr); // get width, height, bit-depth and color-type png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth, &iColorType, NULL, NULL, NULL); // expand images of all color-type and bit-depth to 4x8 bit RGBA images if (iColorType == PNG_COLOR_TYPE_PALETTE) png_set_expand(png_ptr); if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) png_set_expand(png_ptr); if (iBitDepth < 8) png_set_expand(png_ptr); if (iBitDepth == 16) png_set_strip_16(png_ptr); if (iColorType == PNG_COLOR_TYPE_GRAY || iColorType == PNG_COLOR_TYPE_GRAY_ALPHA) png_set_gray_to_rgb(png_ptr); // if required set gamma conversion if (png_get_gAMA(png_ptr, info_ptr, &dGamma)) png_set_gamma(png_ptr, (double) 2.2, dGamma); // after the transformations have been registered update info_ptr data png_read_update_info(png_ptr, info_ptr); // get again width, height and the new bit-depth and color-type png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth, &iColorType, NULL, NULL, NULL); ---- People will correct me :-) when this can be done better .... -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 9 09:31:40 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id JAA09358 for ; Thu, 9 Aug 2001 09:31:39 -0500 (CDT) Received: by webshld.ccf.swri.edu; id JAA17046; Thu, 9 Aug 2001 09:29:51 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAFfaqsH; Thu, 9 Aug 01 09:29:50 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f79EOnY12139 for ; Thu, 9 Aug 2001 09:24:49 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f79EVOh11929; Thu, 9 Aug 2001 09:31:24 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f79EVN411924 for ; Thu, 9 Aug 2001 09:31:23 -0500 (CDT) Received: (qmail 26351 invoked from network); 9 Aug 2001 14:31:26 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 9 Aug 2001 14:31:26 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f79ETHe14186 for png-implement@ccrc.wustl.edu; Thu, 9 Aug 2001 07:29:17 -0700 Date: Thu, 9 Aug 2001 07:29:17 -0700 Message-Id: <200108091429.f79ETHe14186@sonic.net> From: Greg Roelofs To: png-implement@ccrc.wustl.edu Subject: Re: Legal transformations? Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List > >Question from Mattias: > >If I want every kind of PNG file I get to decompress into an RGBA buffer > >with 4 bytes for every pixels, can I simply set all the transformation bits > >or do I have to analyze the colortype and bitdepth before I use them? > Answer from Willem: > I often use the following piece of code to convert any PNG into 4x8: [code] That doesn't add a blank alpha channel to images lacking transparency, though, does it? It looks very much like what I do in the rpng/rpng2 code, and I know I get both RGB and RGBA out of that. You also need one of these, I think: png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER); (first testing whether tRNS was valid or there was an alpha channel). Greg -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 9 12:52:44 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id MAA11153 for ; Thu, 9 Aug 2001 12:52:44 -0500 (CDT) Received: by webshld.ccf.swri.edu; id MAA18123; Thu, 9 Aug 2001 12:50:55 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAEFaazJ; Thu, 9 Aug 01 12:50:54 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f79HjrY23765 for ; Thu, 9 Aug 2001 12:45:53 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f79HqFR15698; Thu, 9 Aug 2001 12:52:15 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from linux1.anark.com (linux1.anark.com [216.17.159.252]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f79HqE415693 for ; Thu, 9 Aug 2001 12:52:14 -0500 (CDT) Received: from MFORNANDER (station213.anark.com [216.17.159.213]) by linux1.anark.com (8.11.1/8.11.1) with SMTP id f79HqI901247 for ; Thu, 9 Aug 2001 11:52:18 -0600 From: "Mattias Fornander" To: "PNG Implementation List" Subject: RE: Legal transformations? Date: Thu, 9 Aug 2001 11:52:18 -0600 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal In-Reply-To: <200108091429.f79ETHe14186@sonic.net> X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List What I'm worried about is certain combinations of settings upsetting the transform pipeline. For example, according to the docs, png_set_filler requires the bitdepth to be 8bit. Now if I've asked it to expand using png_set_expand just before that call, is it going be happy when I call png_read_update_info and png_read_image? png_set_xxx calls all translate to PNG_TRANSFORM_XXX bits that in turn translate to pixel transforms, correct? Some of these transforms make sense on some decompressed data, some don't. It all must depend on the order that these bits are read and turned into operations. If expand actually expands to 8bits BEFORE filler gets a chance to add the alpha byte it would work. If the implementation read the bits in reverse order it would upset it. Would this code ALWAYS be valid and turn all PNGs into 8x4 (8bit channel RGBA) no matter what PNG you threw at it? : //====================================================== // Read image information png_read_info( thePNGData, thePNGInfo ); png_get_IHDR( thePNGData, thePNGInfo, &theWidth, &theHeight, &theBitDepth, &theColorType, NULL, NULL, NULL ); // Allocate memory outDest = new BYTE[ theWidth * theHeight * 4 ]; // Point row pointers theRowPointers = new png_bytep[ outHeight ]; for ( unsigned long theRowIndex = 0; theRowIndex < outHeight; ++ theRowIndex ) { theRowPointers[ theRowIndex ] = outDest + outWidth * theRowIndex * 4; } // Expand images of all color-type and bit-depth to 4x8 bit RGBA images: // Expand palette, <8 bits and/or transparency chunk if ( theColorType == PNG_COLOR_TYPE_PALETTE || theBitDepth < 8 || png_get_valid( thePNGData, thePNGInfo, PNG_INFO_tRNS ) ) { png_set_expand( thePNGData ); } // (we should now have 8bit channel data?) // Convert gray to RGB if ( theColorType == PNG_COLOR_TYPE_GRAY || theColorType == PNG_COLOR_TYPE_GRAY_ALPHA ) { png_set_gray_to_rgb( thePNGData ); } // (we should now have RGB or RGBA data?) // Add alpha if not there if ( !(theColorType & PNG_COLOR_MASK_ALPHA) && !png_get_valid( thePNGData, thePNGInfo, PNG_INFO_tRNS ) ) { png_set_filler( thePNGData, 0xFF, PNG_FILLER_AFTER ); } / (we should now always have RGBA data?) // After the transformations have been registered update info_ptr data png_read_update_info( thePNGData, thePNGInfo ); // Get again width, height and the new bit-depth and color-type png_get_IHDR( thePNGData, thePNGInfo, &theWidth, &theHeight, &theBitDepth, &theColorType, NULL, NULL, NULL ); // Read image data png_read_image( thePNGData, theRowPointers ); //====================================================== -----Original Message----- From: owner-png-implement@ccrc.wustl.edu [mailto:owner-png-implement@ccrc.wustl.edu]On Behalf Of Greg Roelofs Sent: Thursday, August 09, 2001 8:29 AM To: png-implement@ccrc.wustl.edu Subject: Re: Legal transformations? > >Question from Mattias: > >If I want every kind of PNG file I get to decompress into an RGBA buffer > >with 4 bytes for every pixels, can I simply set all the transformation bits > >or do I have to analyze the colortype and bitdepth before I use them? > Answer from Willem: > I often use the following piece of code to convert any PNG into 4x8: [code] That doesn't add a blank alpha channel to images lacking transparency, though, does it? It looks very much like what I do in the rpng/rpng2 code, and I know I get both RGB and RGBA out of that. You also need one of these, I think: png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER); (first testing whether tRNS was valid or there was an alpha channel). Greg -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 9 13:04:10 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id NAA11262 for ; Thu, 9 Aug 2001 13:04:10 -0500 (CDT) Received: by webshld.ccf.swri.edu; id NAA19859; Thu, 9 Aug 2001 13:02:21 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAn_aqYM; Thu, 9 Aug 01 13:02:20 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f79HvJY24493 for ; Thu, 9 Aug 2001 12:57:19 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f79I3dU15969; Thu, 9 Aug 2001 13:03:39 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f79I3c415965 for ; Thu, 9 Aug 2001 13:03:39 -0500 (CDT) Received: from volans (129.37.150.75) by mail.san.yahoo.com (5.5.041.1) id 3B708C180007CF3A for png-implement@ccrc.wustl.edu; Thu, 9 Aug 2001 11:02:25 -0700 Message-Id: <3.0.3.32.20010809120316.00739180@mail.schaik.com> X-Sender: willemschaik@mail.schaik.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Date: Thu, 09 Aug 2001 12:03:16 -0600 To: PNG Implementation List From: Willem van Schaik Subject: Re: Legal transformations? In-Reply-To: <200108091429.f79ETHe14186@sonic.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List >> Answer from Willem: >> I often use the following piece of code to convert any PNG into 4x8: > [code] > > Greg added: >That doesn't add a blank alpha channel to images lacking transparency, >though, does it? It looks very much like what I do in the rpng/rpng2 >code, and I know I get both RGB and RGBA out of that. You also need >one of these, I think: > png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER); >(first testing whether tRNS was valid or there was an alpha channel). Yeppp, you're right. Checked my code and I did something similar. Willem -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 9 15:12:48 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id PAA12530 for ; Thu, 9 Aug 2001 15:12:48 -0500 (CDT) Received: by webshld.ccf.swri.edu; id PAA09037; Thu, 9 Aug 2001 15:10:59 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAIiaqPr; Thu, 9 Aug 01 15:10:58 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f79K5wY01826 for ; Thu, 9 Aug 2001 15:05:58 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f79KCT218388; Thu, 9 Aug 2001 15:12:29 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail18.sdc1.sfba.home.com (femail18.sdc1.sfba.home.com [24.0.95.145]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f79KCS418384 for ; Thu, 9 Aug 2001 15:12:28 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail18.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010809201233.GYCK3087.femail18.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com> for ; Thu, 9 Aug 2001 13:12:33 -0700 Message-Id: <3.0.6.32.20010809161016.00f956f0@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Thu, 09 Aug 2001 16:10:16 -0400 To: PNG Implementation List From: Glenn Randers-Pehrson Subject: RE: Legal transformations? In-Reply-To: References: <200108091429.f79ETHe14186@sonic.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 11:52 AM 8/9/01 -0600, Mattias Fornander wrote: >according to the docs, png_set_filler >requires the bitdepth to be 8bit. That's not true though, since version 1.0.2. The test for bit_depth==8 can be removed from line 810 of libpng.txt. > >png_set_xxx calls all translate to PNG_TRANSFORM_XXX bits that in turn >translate to pixel transforms, correct? Some of these transforms make sense >on some decompressed data, some don't. It all must depend on the order that >these bits are read and turned into operations. If expand actually expands >to 8bits BEFORE filler gets a chance to add the alpha byte it would work. >If the implementation read the bits in reverse order it would upset it. You can look at the png_do_read_transformations() function in pngrtran.c to determine in what order the transformations are done. In fact, the "expand" procedure is done before the "filler" procedure. Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Fri Aug 10 10:59:48 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id KAA18291 for ; Fri, 10 Aug 2001 10:59:48 -0500 (CDT) Received: by webshld.ccf.swri.edu; id KAA17953; Fri, 10 Aug 2001 10:57:58 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAA0aaeJ; Fri, 10 Aug 01 10:57:58 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7AFqwY16340 for ; Fri, 10 Aug 2001 10:52:58 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7AFx0v00708; Fri, 10 Aug 2001 10:59:00 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f7AFwx400704 for ; Fri, 10 Aug 2001 10:58:59 -0500 (CDT) Received: (qmail 26934 invoked from network); 10 Aug 2001 15:58:59 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 10 Aug 2001 15:58:59 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f7AFumN14530 for png-implement@ccrc.wustl.edu; Fri, 10 Aug 2001 08:56:48 -0700 Date: Fri, 10 Aug 2001 08:56:48 -0700 Message-Id: <200108101556.f7AFumN14530@sonic.net> From: Greg Roelofs To: png-implement@ccrc.wustl.edu Subject: RE: Legal transformations? Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Mattias Fornander wrote: > What I'm worried about is certain combinations of settings upsetting the > transform pipeline. For example, according to the docs, png_set_filler > requires the bitdepth to be 8bit. Now if I've asked it to expand using > png_set_expand just before that call, is it going be happy when I call > png_read_update_info and png_read_image? As Glenn noted, you can check one of the routines to see the exact order of transformation, although it's fairly complex. The other thing to be aware of is that, indeed, you're just setting flags at this point; even png_read_update_info() merely recalculates some parameters based on the flags. The transforms don't actually *happen* until you're reading pixel data, and that's where the routine that Glenn mentioned comes in. > Would this code ALWAYS be valid and turn all PNGs into 8x4 (8bit channel > RGBA) no matter what PNG you threw at it? : It certainly should be. I've never seen a case where it didn't work, and there have been enough implementations at this point that it *should* be pretty close to perfect. You could always test against the dozen or so basn*.png images in PngSuite, however; they exercise all combos of bit depth and image type. (Toss in the basi*.png set if you want to check up on deinterlacing, too.) Greg -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sun Aug 12 15:27:26 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id PAA28545 for ; Sun, 12 Aug 2001 15:27:23 -0500 (CDT) Received: by webshld.ccf.swri.edu; id PAA00573; Sun, 12 Aug 2001 15:25:32 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAvwaGhb; Sun, 12 Aug 01 15:25:30 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7CKKSi01375 for ; Sun, 12 Aug 2001 15:20:28 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7BGX3G16705; Sat, 11 Aug 2001 11:33:03 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from hermes.med-web.com (mail.med-web.com [207.175.164.123]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7BGX2416701 for ; Sat, 11 Aug 2001 11:33:02 -0500 (CDT) Received: from med-web.com (dialin005.med-web.com [207.2.113.5]) by hermes.med-web.com (8.9.3/8.9.3) with ESMTP id LAA23441 for ; Sat, 11 Aug 2001 11:32:59 -0500 Message-ID: <3B755E66.DD71C76C@med-web.com> Date: Sat, 11 Aug 2001 11:33:42 -0500 From: Jason Summers X-Mailer: Mozilla 4.7 [en] (Win98; I) X-Accept-Language: en MIME-Version: 1.0 To: PNG Implementation List Subject: Re: png bug References: <000001c11f5d$98b801a0$0a00a8c0@odd.local> <3B715492.7F2A8051@med-web.com> <20010808175051.A30862@ecs.soton.ac.uk> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Nick Lamb wrote: > > On Wed, Aug 08, 2001 at 10:02:42AM -0500, Jason Summers wrote: > > and http://entropymine.com/jason/testbed/pngtrans/ > > Wow, that's much better than mine. What are your feelings about linking > to it/ copying it (with credit) in its entirety? Links are fine. You may make a copy of it if you want (or adapt it for your own use); I'd just prefer that there not be too many unmaintained copies of it lying around on the web, since it's far from perfect. > > BTW The Win32-binary-transparency bug is an old classic. Probably just > poking the people who solved it last time would be a good start to > getting it fixed in 0.9.x There have been several transparency bugs. I think this particular one was introduced with the new imaging library (libimg2 aka libpr0n) in about April 2001 (though I could be wrong..). -- Jason Summers jason1@pobox.com http://entropymine.com/jason/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Tue Aug 14 19:11:11 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id TAA15495 for ; Tue, 14 Aug 2001 19:11:11 -0500 (CDT) Received: by webshld.ccf.swri.edu; id TAA28019; Tue, 14 Aug 2001 19:09:17 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAttaqU2; Tue, 14 Aug 01 19:09:15 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7F04C915363 for ; Tue, 14 Aug 2001 19:04:13 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7F08Tl02329; Tue, 14 Aug 2001 19:08:29 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from linux1.anark.com (linux1.anark.com [216.17.159.252]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7F08S402325 for ; Tue, 14 Aug 2001 19:08:28 -0500 (CDT) Received: from MFORNANDER (station213.anark.com [216.17.159.213]) by linux1.anark.com (8.11.1/8.11.1) with SMTP id f7F08P905219 for ; Tue, 14 Aug 2001 18:08:31 -0600 From: "Mattias Fornander" To: "PNG Implementation List" Subject: Packing bits Date: Tue, 14 Aug 2001 18:08:25 -0600 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Importance: Normal In-Reply-To: Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Hi all, >From the manual I get this: PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as they can, resulting in, for example, 8 pixels per byte for 1 bit files. If the data is supplied at 1 pixel per byte, use this code, which will correctly pack the pixels into a single byte: png_set_packing(png_ptr); My data is 8 bits per pixel but I have a palette with 16, 4 or 2 entries. So, each byte only uses the four/two/one least significant bits. I understand the above explanation of png_set_packing to be that LibPNG will pack the pixels for me if I give it 8bit data with 4/2/1bit information. Looking at filesizes I dind't see a jump at all at the 16color boundaries that would indicate that LibPNG was packing 2 pixels in every byte. Setting png_set_IHDR to bitdepth = 4 I got the decrease in filesize but it then thought that my input data has two pixels per byte. Question: Does LibPNG have a mode to pack 8bit data into 4/2/1bit or do I have to twiddle the bits muself before I call png_write_png? What does png_set_packing actually do? Thanks! Mattias -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Tue Aug 14 20:29:11 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id UAA15763 for ; Tue, 14 Aug 2001 20:29:11 -0500 (CDT) Received: by webshld.ccf.swri.edu; id UAA02205; Tue, 14 Aug 2001 20:27:17 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA3zaGte; Tue, 14 Aug 01 20:27:17 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7F1ME917804 for ; Tue, 14 Aug 2001 20:22:14 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7F1Slc02854; Tue, 14 Aug 2001 20:28:47 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from himalaya.etrieve.com (mail.etrieve.com [198.107.63.171]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7F1Sk402850 for ; Tue, 14 Aug 2001 20:28:46 -0500 (CDT) Received: by HIMALAYA with Internet Mail Service (5.5.2653.19) id ; Tue, 14 Aug 2001 18:22:38 -0700 Message-ID: From: Eric Fu To: png-implement@ccrc.wustl.edu Subject: Open source for resizing png files Date: Tue, 14 Aug 2001 18:22:33 -0700 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Anyone knows of any open source code for resizing (especially reducing) png files? Eric -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Tue Aug 14 20:56:40 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id UAA15875 for ; Tue, 14 Aug 2001 20:56:39 -0500 (CDT) Received: by webshld.ccf.swri.edu; id UAA03810; Tue, 14 Aug 2001 20:54:46 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA81aiCh; Tue, 14 Aug 01 20:54:45 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7F1nh918752 for ; Tue, 14 Aug 2001 20:49:43 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7F1uQ903011; Tue, 14 Aug 2001 20:56:26 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7F1uP403007 for ; Tue, 14 Aug 2001 20:56:25 -0500 (CDT) Received: from volans (129.37.161.77) by mail.san.yahoo.com (5.5.041.1) id 3B7978810001959F for png-implement@ccrc.wustl.edu; Tue, 14 Aug 2001 18:55:27 -0700 Message-Id: <3.0.3.32.20010814195534.007515dc@mail.schaik.com> X-Sender: willemschaik@mail.schaik.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Date: Tue, 14 Aug 2001 19:55:34 -0600 To: PNG Implementation List From: Willem van Schaik Subject: Re: Open source for resizing png files In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Yes, look at the sourcecode of pnmscale. Part of "netpbm", which project can be found at "http://www.sourceforge.net/projects/netpbm". Willem At 18:22 14-08-01 -0700, you wrote: >Anyone knows of any open source code for resizing (especially reducing) png >files? > >Eric > > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Tue Aug 14 23:04:17 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34] (may be forged)) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id XAA16304 for ; Tue, 14 Aug 2001 23:04:17 -0500 (CDT) Received: by webshld.ccf.swri.edu; id XAA10984; Tue, 14 Aug 2001 23:02:23 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAOwa4Cv; Tue, 14 Aug 01 23:02:23 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7F3vK922743 for ; Tue, 14 Aug 2001 22:57:20 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7F43tq03841; Tue, 14 Aug 2001 23:03:55 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7F43r403837 for ; Tue, 14 Aug 2001 23:03:53 -0500 (CDT) Received: from volans (129.37.161.77) by mail.san.yahoo.com (5.5.041.1) id 3B7978810001F490; Tue, 14 Aug 2001 21:02:59 -0700 Message-Id: <3.0.3.32.20010814220342.0073b240@mail.schaik.com> X-Sender: willemschaik@mail.schaik.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Date: Tue, 14 Aug 2001 22:03:42 -0600 To: PNG Implementation List From: Willem van Schaik Subject: bug in GnuWin32 netpbm 9.14 fixed in 9.14-1 In-Reply-To: <3.0.6.32.20010808103447.00f8c6a0@netmail.home.com> References: <3.0.6.32.20010723080005.00e3d160@netmail.home.com> <200107211820.f6LIKtM18223@sonic.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List There was some discussion going around (big part caused by me) about a bug in the GnuWin32 binaries of netpbm (which contains pnmtopng) having to do with opening the files not in binary mode. Luckily I can tell now that this has been fixed in version 9.14-1. So you should download a new version from SourceForge, in the GnuWin32 project: http://prdownloads.sourceforge.net/gnuwin32/netpbm-9.14-1-bin.zip. It's nice to have now a good working pnmtopng/pngtopnm that runs in a Windows DOS box. It's also way faster than the old versions that required dos-extenders. Willem -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 15 09:58:44 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id JAA19119 for ; Wed, 15 Aug 2001 09:58:44 -0500 (CDT) Received: by webshld.ccf.swri.edu; id JAA00050; Wed, 15 Aug 2001 09:56:50 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA_0aiga; Wed, 15 Aug 01 09:56:49 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7FEpjV14645 for ; Wed, 15 Aug 2001 09:51:45 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7FEwOY07536; Wed, 15 Aug 2001 09:58:24 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from webber.adilger.int (h24-64-71-161.cg.shawcable.net [24.64.71.161]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7FEwJ407529 for ; Wed, 15 Aug 2001 09:58:23 -0500 (CDT) Received: from webber.adilger.int (adilger@localhost [127.0.0.1]) by localhost (8.12.0.Beta10/8.12.0.Beta10/Debian 8.12.0.Beta10) with ESMTP id f7FEwH2j012971; Wed, 15 Aug 2001 08:58:17 -0600 Received: (from adilger@localhost) by webber.adilger.int (8.12.0.Beta10/8.12.0.Beta10/Debian 8.12.0.Beta10) id f7FEwCms012969; Wed, 15 Aug 2001 08:58:12 -0600 From: Andreas Dilger Message-Id: <200108151458.f7FEwCms012969@webber.adilger.int> Subject: Re: LibPNG In-Reply-To: <1072700513.20010816085546@softhome.net> "from Oleg M. at Aug 16, 2001 08:55:46 am" To: "Oleg M." Date: Wed, 15 Aug 2001 08:58:12 -0600 (MDT) CC: PNG Implementation X-Mailer: ELM [version 2.4ME+ PL87 (25)] MIME-Version: 1.0 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Oleg, you write: > Please forward this message to someone who can help in troubleshooting > an application that uses LibPNG. I have forwarded this email to the png-implement mailing list. Unfortunately, I don't really know very much about programming on the Windows platform, as all of my experience has been in the Unix area. I suspect someone else on the list can help. Cheers, Andreas > ------------------------------------------------------------------- > Problem description: > > Program crash on some(!) PNG files during attempt to call > "png_read_info" function. The pointers supplied to the function are > valid and some PNG images are processed well. > > Background: > > - Microsoft Visual C++ 6.0 is used; > - LibPNG was compiled as static library without any "PNG_" > pre-processor definitions. The PNG.LIB file is about 280kb. > - The function that uses png is in DLL that is loaded with LoadLibrary > function and GetProcAddress are farther used. > - Both LibPNG and my plug-in were compiled using "Multithreaded DLL" > runtime library. > - Combinations of PNG_USES_DLL and PNG_BUILD_DLL directives were > tried also. > > I'm not an experienced C/C++ programmer, but i suppose I've build > invalid LibPNG.lib file (source code and header files were directly > used to build the library). > The similar crashes had happen when my functions were not "CALLBACK", > so i suppose something wrong with compiling directives. > > ************* > problem code: > fread (buf, 1, 8, png_file); > //...png_check_sig... > png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING, > NULL, NULL, NULL); > info_ptr = png_create_info_struct (png_ptr); > if (setjmp (png_jmpbuf(png_ptr))) > { > png_destroy_read_struct (&png_ptr, &info_ptr, NULL); > return (DWORD)NULL; > } > // set up the input control for C streams > png_init_io (png_ptr, png_file); > png_set_sig_bytes (png_ptr, 8);// we already read the 8 signature bytes > > // Here everything is ok on ALL images > png_read_info (png_ptr, info_ptr); /* CRASH */ > // the crash is somewhere in png_read_info or in calling conversion. > ************* > > Finally, can you please send me LibPNG.lib static library for MS > Visual C++, that can be used when building/linking my DLL. > > Thanks. > > ------------------------------------------------------------------- > > > Regards, Oleg M. > > > -- Andreas Dilger \ "If a man ate a pound of pasta and a pound of antipasto, \ would they cancel out, leaving him still hungry?" http://www-mddsp.enel.ucalgary.ca/People/adilger/ -- Dogbert -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 15 11:37:11 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id LAA19887 for ; Wed, 15 Aug 2001 11:37:11 -0500 (CDT) Received: by webshld.ccf.swri.edu; id LAA20615; Wed, 15 Aug 2001 11:35:17 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAdGaqqO; Wed, 15 Aug 01 11:35:14 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7FGUCV20982 for ; Wed, 15 Aug 2001 11:30:12 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7FGaqP09186; Wed, 15 Aug 2001 11:36:52 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7FGaq409182 for ; Wed, 15 Aug 2001 11:36:52 -0500 (CDT) Received: from [192.9.51.3] by mail.san.yahoo.com with HTTP; Wed, 15 Aug 2001 09:35:53 -0700 Message-ID: <3B708CFA00003449@mail.san.yahoo.com> Date: Wed, 15 Aug 2001 10:35:53 -0600 In-Reply-To: <200108151458.f7FEwCms012969@webber.adilger.int> From: =?iso-8859-1?Q?Willem=20van=20Schaik?= Subject: =?iso-8859-1?Q?Re=3A=20LibPNG?= To: =?iso-8859-1?Q?PNG=20Implementation=20List?= , =?iso-8859-1?Q?Oleg=20M=2E?= MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by ccrc.wustl.edu id f7FGaq409183 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Oleg, I think, you get something mixed up. You mention that you built a static libpng.lib. Seeing the size of 280k for the .lib confirms that. But when you have a static libpng.lib, you should just link that library statically into your application. In settings, just add it to the list of libraries. After that forget about all .dll stuff. So no LoadLibary calls and such. Or you have to go the complete opposite route, which means, compiling libpng as a dynamic library, which results in a small .lib file (to be linked into your application) that contains the interface with the routines themselves, that are then part of the libpng.dll. In the contrib folder of libpng, you find working examples for building and using libpng under Visual C++ 6.0. These can be built both static and dynamic. I would recommend you first to see you if you can get those example programs working and than extend from there. Willem -- Original Message -- > >Oleg, you write: >> Please forward this message to someone who can help in troubleshooting >> an application that uses LibPNG. > >I have forwarded this email to the png-implement mailing list. Unfortunately, >I don't really know very much about programming on the Windows platform, >as >all of my experience has been in the Unix area. I suspect someone else on >the list can help. > >Cheers, Andreas >> ------------------------------------------------------------------- >> Problem description: >> >> Program crash on some(!) PNG files during attempt to call >> "png_read_info" function. The pointers supplied to the function are >> valid and some PNG images are processed well. >> >> Background: >> >> - Microsoft Visual C++ 6.0 is used; >> - LibPNG was compiled as static library without any "PNG_" >> pre-processor definitions. The PNG.LIB file is about 280kb. >> - The function that uses png is in DLL that is loaded with LoadLibrary >> function and GetProcAddress are farther used. >> - Both LibPNG and my plug-in were compiled using "Multithreaded DLL" >> runtime library. >> - Combinations of PNG_USES_DLL and PNG_BUILD_DLL directives were >> tried also. >> >> I'm not an experienced C/C++ programmer, but i suppose I've build >> invalid LibPNG.lib file (source code and header files were directly >> used to build the library). >> The similar crashes had happen when my functions were not "CALLBACK", >> so i suppose something wrong with compiling directives. >> >> ************* >> problem code: >> fread (buf, 1, 8, png_file); >> //...png_check_sig... >> png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING, >> NULL, NULL, NULL); >> info_ptr = png_create_info_struct (png_ptr); >> if (setjmp (png_jmpbuf(png_ptr))) >> { >> png_destroy_read_struct (&png_ptr, &info_ptr, NULL); >> return (DWORD)NULL; >> } >> // set up the input control for C streams >> png_init_io (png_ptr, png_file); >> png_set_sig_bytes (png_ptr, 8);// we already read the 8 signature >bytes >> >> // Here everything is ok on ALL images >> png_read_info (png_ptr, info_ptr); /* CRASH */ >> // the crash is somewhere in png_read_info or in calling conversion. >> ************* >> >> Finally, can you please send me LibPNG.lib static library for MS >> Visual C++, that can be used when building/linking my DLL. >> >> Thanks. >> >> ------------------------------------------------------------------- >> >> >> Regards, Oleg M. >> >> >> > >-- >Andreas Dilger \ "If a man ate a pound of pasta and a pound of antipasto, > \ would they cancel out, leaving him still hungry?" >http://www-mddsp.enel.ucalgary.ca/People/adilger/ -- Dogbert > > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > v a n S c h a i k ------------------------------------------------------------------------ Willem van Schaik willem@schaik.com -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 15 16:57:25 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id QAA22351 for ; Wed, 15 Aug 2001 16:57:25 -0500 (CDT) Received: by webshld.ccf.swri.edu; id QAA17635; Wed, 15 Aug 2001 16:55:30 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAT2aqCI; Wed, 15 Aug 01 16:55:30 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7FLoRS09740 for ; Wed, 15 Aug 2001 16:50:27 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7FLv6Q14722; Wed, 15 Aug 2001 16:57:06 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from himalaya.etrieve.com (mail.etrieve.com [198.107.63.171]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7FLv5414718 for ; Wed, 15 Aug 2001 16:57:05 -0500 (CDT) Received: by HIMALAYA with Internet Mail Service (5.5.2653.19) id ; Wed, 15 Aug 2001 14:50:47 -0700 Message-ID: From: Eric Fu To: PNG Implementation List Subject: RE: Open source for resizing png files Date: Wed, 15 Aug 2001 14:50:45 -0700 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Well, I've tried that. It doesn't work because of a problem with "pnmtopng". It seems I have to go through a few steps: 1) png => pnm 2) pnmscale 3) pnm => png The last step doesn't work: the image produced by pnmtopng can not be read by any viewer. Any one has the same problem with pnmtopng? Also, any open source that scales PNG directly WITHOUT the intermediate steps? Eric -----Original Message----- From: Willem van Schaik [mailto:willem@schaik.com] Sent: Tuesday, August 14, 2001 6:56 PM To: PNG Implementation List Subject: Re: Open source for resizing png files Yes, look at the sourcecode of pnmscale. Part of "netpbm", which project can be found at "http://www.sourceforge.net/projects/netpbm". Willem At 18:22 14-08-01 -0700, you wrote: >Anyone knows of any open source code for resizing (especially reducing) png >files? > >Eric > > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 15 17:10:02 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id RAA22515 for ; Wed, 15 Aug 2001 17:10:01 -0500 (CDT) Received: by webshld.ccf.swri.edu; id RAA20305; Wed, 15 Aug 2001 17:08:07 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAALMaaQN; Wed, 15 Aug 01 17:08:07 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7FM33S10404 for ; Wed, 15 Aug 2001 17:03:03 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7FM9oc14835; Wed, 15 Aug 2001 17:09:50 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from himalaya.etrieve.com (mail.etrieve.com [198.107.63.171]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7FM9n414831 for ; Wed, 15 Aug 2001 17:09:50 -0500 (CDT) Received: by HIMALAYA with Internet Mail Service (5.5.2653.19) id ; Wed, 15 Aug 2001 15:03:37 -0700 Message-ID: From: Eric Fu To: PNG Implementation List Subject: pnmtopng broken Date: Wed, 15 Aug 2001 15:03:33 -0700 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List I am using netpbm 9.16. My problem is the png image this tool produced seems to be corrupted. I have run through pngcheck and verified. Anyone got this "pnmtopng" working? eric -----Original Message----- From: Willem van Schaik [mailto:willem@schaik.com] Sent: Tuesday, August 14, 2001 6:56 PM To: PNG Implementation List Subject: Re: Open source for resizing png files Yes, look at the sourcecode of pnmscale. Part of "netpbm", which project can be found at "http://www.sourceforge.net/projects/netpbm". Willem At 18:22 14-08-01 -0700, you wrote: >Anyone knows of any open source code for resizing (especially reducing) png >files? > >Eric > > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 15 17:49:27 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id RAA22695 for ; Wed, 15 Aug 2001 17:49:27 -0500 (CDT) Received: by webshld.ccf.swri.edu; id RAA24761; Wed, 15 Aug 2001 17:47:33 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAKkaaxW; Wed, 15 Aug 01 17:47:32 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7FMgJS12108 for ; Wed, 15 Aug 2001 17:42:19 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7FMmvI15056; Wed, 15 Aug 2001 17:48:57 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail17.sdc1.sfba.home.com (femail17.sdc1.sfba.home.com [24.0.95.144]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7FMmu415052 for ; Wed, 15 Aug 2001 17:48:56 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail17.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010815224901.BIUC152.femail17.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com> for ; Wed, 15 Aug 2001 15:49:01 -0700 Message-Id: <3.0.6.32.20010815184633.00e44700@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Wed, 15 Aug 2001 18:46:33 -0400 To: PNG Implementation List From: Glenn Randers-Pehrson Subject: RE: Open source for resizing png files In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 02:50 PM 8/15/01 -0700, Eric Fu wrote: >Also, any open source that scales PNG directly WITHOUT the intermediate >steps? ImageMagick's "convert" with "-geometry WxH" or "-sample WxH" options. http://www.imagemagick.org Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 15 17:51:00 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id RAA22729 for ; Wed, 15 Aug 2001 17:51:00 -0500 (CDT) Received: by webshld.ccf.swri.edu; id RAA24895; Wed, 15 Aug 2001 17:49:05 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAPXaWNW; Wed, 15 Aug 01 17:49:05 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7FMhaS12190 for ; Wed, 15 Aug 2001 17:43:46 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7FMo7k15069; Wed, 15 Aug 2001 17:50:07 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7FMo6415065 for ; Wed, 15 Aug 2001 17:50:06 -0500 (CDT) Received: from [192.9.51.3] by mail.san.yahoo.com with HTTP; Wed, 15 Aug 2001 15:49:10 -0700 Message-ID: <3B708CFA000037BE@mail.san.yahoo.com> Date: Wed, 15 Aug 2001 16:49:10 -0600 In-Reply-To: From: =?iso-8859-1?Q?Willem=20van=20Schaik?= Subject: =?iso-8859-1?Q?RE=3A=20Open=20source=20for=20resizing=20png=20files?= To: =?iso-8859-1?Q?PNG=20Implementation=20List?= MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by ccrc.wustl.edu id f7FMo6415066 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List > >Also, any open source that scales PNG directly WITHOUT the intermediate >steps? > The source of pnmscale is 100% open. It remains of course your job to integrate that with your own application. Unless you mean something different, which is "a freeware program that can scale images and that reads/writes in PNG format". In that case better first state your platform and better check http://www.libpng.org/pub/png/pngapps.html. Willem >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > v a n S c h a i k ------------------------------------------------------------------------ Willem van Schaik willem@schaik.com -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 15 17:52:14 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id RAA22743 for ; Wed, 15 Aug 2001 17:52:14 -0500 (CDT) Received: by webshld.ccf.swri.edu; id RAA25015; Wed, 15 Aug 2001 17:50:19 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAALVaO2W; Wed, 15 Aug 01 17:50:18 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7FMjAS12260 for ; Wed, 15 Aug 2001 17:45:10 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7FMprB15082; Wed, 15 Aug 2001 17:51:53 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7FMpq415078 for ; Wed, 15 Aug 2001 17:51:52 -0500 (CDT) Received: from [192.9.51.3] by mail.san.yahoo.com with HTTP; Wed, 15 Aug 2001 15:50:56 -0700 Message-ID: <3B708CFA000037C5@mail.san.yahoo.com> Date: Wed, 15 Aug 2001 16:50:56 -0600 In-Reply-To: From: =?iso-8859-1?Q?Willem=20van=20Schaik?= Subject: =?iso-8859-1?Q?RE=3A=20pnmtopng=20broken?= To: =?iso-8859-1?Q?PNG=20Implementation=20List?= MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by ccrc.wustl.edu id f7FMpq415079 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Hi Eric, Few questions: what platform did you build pnmtopng? Which libpng version? Did earlier versions like 9.14/9.15 work OK for you? Willem -- Original Message -- >I am using netpbm 9.16. > >My problem is the png image this tool produced seems to be corrupted. I have >run through pngcheck and verified. > >Anyone got this "pnmtopng" working? > >eric > > >-----Original Message----- >From: Willem van Schaik [mailto:willem@schaik.com] >Sent: Tuesday, August 14, 2001 6:56 PM >To: PNG Implementation List >Subject: Re: Open source for resizing png files > > >Yes, look at the sourcecode of pnmscale. Part of "netpbm", which project >can be found at "http://www.sourceforge.net/projects/netpbm". > >Willem > > > >At 18:22 14-08-01 -0700, you wrote: >>Anyone knows of any open source code for resizing (especially reducing) >png >>files? >> >>Eric >> >> >>-- >>Send the message body "help" to png-implement-request@ccrc.wustl.edu >> > > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > v a n S c h a i k ------------------------------------------------------------------------ Willem van Schaik willem@schaik.com -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 15 18:30:47 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id SAA22855 for ; Wed, 15 Aug 2001 18:30:46 -0500 (CDT) Received: by webshld.ccf.swri.edu; id SAA27560; Wed, 15 Aug 2001 18:28:52 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA3Aa401; Wed, 15 Aug 01 18:28:51 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7FNNcS13668 for ; Wed, 15 Aug 2001 18:23:43 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7FNU6N15319; Wed, 15 Aug 2001 18:30:06 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from himalaya.etrieve.com (mail.etrieve.com [198.107.63.171]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7FNU5415315 for ; Wed, 15 Aug 2001 18:30:05 -0500 (CDT) Received: by HIMALAYA with Internet Mail Service (5.5.2653.19) id ; Wed, 15 Aug 2001 16:23:53 -0700 Message-ID: From: Eric Fu To: PNG Implementation List Subject: RE: pnmtopng broken Date: Wed, 15 Aug 2001 16:23:50 -0700 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by ccrc.wustl.edu id f7FNU5415316 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List I am running on Cygwin platform, using libpng 1.0.11 I tried 9.14, it produced the same (bad) result. I also did a binary dump of the png files, and here's what I found: The 'good' file, i.e. my original png file looks like this: ------------------------------------------------------ [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789012345] 00000: 89 50 4E 47 0D 0A 1A 0A 00 00 00 0D 49 48 44 52 |ëPNG........IHDR| 00016: 00 00 02 D0 00 00 02 1C 08 02 00 00 00 50 1F 0E |..?-..??.?...P??| 00032: 04 00 00 00 01 73 52 47 42 00 AE CE 1C E9 00 00 |?...?sRGB.«+?T..| 00048: 00 09 70 48 59 73 00 00 0B 13 00 00 0B 13 01 00 |..pHYs..??..???.| 00064: 9A 9C 18 00 00 C2 EF 49 44 41 54 78 5E ED BD 07 |Ü£?..-nIDATx^f+.| The 'bad' file, as generated by pnmtopng, looks like this: ------------------------------------------------------ [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789012345] 00000: 89 50 4E 47 0D 0D 0A 1A 0D 0A 00 00 00 0D 49 48 |ëPNG..........IH| 00016: 44 52 00 00 02 D0 00 00 02 1C 08 02 00 00 00 50 |DR..?-..??.?...P| 00032: 1F 0E 04 00 00 20 00 49 44 41 54 78 9C EC BD 79 |???.. .IDATx£8+y| 00048: F4 25 47 75 26 78 DF AF 5E 95 76 09 B4 59 80 F6 |(%Gu&x¯»^òv.¦YÇ÷| 00064: 7D 45 FB 8A 2C 81 8C 19 CC 66 D6 B6 C7 7D E8 F1 |}Evè,üî?¦f+¦¦}F±| 00080: 8C A7 B1 19 2F DD 8D 1B 77 7B 61 F0 7A B0 DD B4 |?/¦ì?w{a=z¦¦¦| Obviously the 'bad' file got a very strange header not confirming to the PNG v1.0 standard, which requires the first 8 bytes to be "89 50 4E 47 0D 0A 1A 0A", not the funny one generated. cheers, Eric -----Original Message----- From: Willem van Schaik [mailto:willem@schaik.com] Sent: Wednesday, August 15, 2001 3:51 PM To: PNG Implementation List Subject: RE: pnmtopng broken Hi Eric, Few questions: what platform did you build pnmtopng? Which libpng version? Did earlier versions like 9.14/9.15 work OK for you? Willem -- Original Message -- >I am using netpbm 9.16. > >My problem is the png image this tool produced seems to be corrupted. I have >run through pngcheck and verified. > >Anyone got this "pnmtopng" working? > >eric > > >-----Original Message----- >From: Willem van Schaik [mailto:willem@schaik.com] >Sent: Tuesday, August 14, 2001 6:56 PM >To: PNG Implementation List >Subject: Re: Open source for resizing png files > > >Yes, look at the sourcecode of pnmscale. Part of "netpbm", which project >can be found at "http://www.sourceforge.net/projects/netpbm". > >Willem > > > >At 18:22 14-08-01 -0700, you wrote: >>Anyone knows of any open source code for resizing (especially reducing) >png >>files? >> >>Eric >> >> >>-- >>Send the message body "help" to png-implement-request@ccrc.wustl.edu >> > > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > v a n S c h a i k ------------------------------------------------------------------------ Willem van Schaik willem@schaik.com -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 15 20:41:00 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id UAA23294 for ; Wed, 15 Aug 2001 20:40:59 -0500 (CDT) Received: by webshld.ccf.swri.edu; id UAA05298; Wed, 15 Aug 2001 20:39:05 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA21aiwk; Wed, 15 Aug 01 20:39:04 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7G1XjS18363 for ; Wed, 15 Aug 2001 20:33:45 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7G1cV116021; Wed, 15 Aug 2001 20:38:31 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail19.sdc1.sfba.home.com (femail19.sdc1.sfba.home.com [24.0.95.128]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7G1cU416017 for ; Wed, 15 Aug 2001 20:38:30 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail19.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010816013835.VXBG13126.femail19.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com> for ; Wed, 15 Aug 2001 18:38:35 -0700 Message-Id: <3.0.6.32.20010815213611.00e442f0@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Wed, 15 Aug 2001 21:36:11 -0400 To: PNG Implementation List From: Glenn Randers-Pehrson Subject: RE: pnmtopng broken In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 04:23 PM 8/15/01 -0700, you wrote: >I am running on Cygwin platform, using libpng 1.0.11 >I tried 9.14, it produced the same (bad) result. >The 'good' file, i.e. my original png file looks like this: >------------------------------------------------------ > [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789012345] >00000: 89 50 4E 47 0D 0A 1A 0A 00 00 00 0D 49 48 44 52 |ëPNG........IHDR| > >The 'bad' file, as generated by pnmtopng, looks like this: >------------------------------------------------------ > [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789012345] >00000: 89 50 4E 47 0D 0D 0A 1A 0D 0A 00 00 00 0D 49 48 |ëPNG..........IH| >Obviously the 'bad' file got a very strange header not confirming to the PNG >v1.0 standard, which requires the first 8 bytes to be "89 50 4E 47 0D 0A 1A >0A", not the funny one generated. Did you transfer the file to another computer before you examined it? You've got CR -> CRLF conversions, like when you do an ASCII ftp transfer. Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Wed Aug 15 21:54:31 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id VAA23542 for ; Wed, 15 Aug 2001 21:54:31 -0500 (CDT) Received: by webshld.ccf.swri.edu; id VAA09311; Wed, 15 Aug 2001 21:52:36 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAS0aWls; Wed, 15 Aug 01 21:52:36 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7G2lQS20632 for ; Wed, 15 Aug 2001 21:47:26 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7G2rwq16551; Wed, 15 Aug 2001 21:53:58 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7G2rw416547 for ; Wed, 15 Aug 2001 21:53:58 -0500 (CDT) Received: from volans (129.37.161.5) by mail.san.yahoo.com (5.5.041.1) id 3B797881000668A7 for png-implement@ccrc.wustl.edu; Wed, 15 Aug 2001 19:52:59 -0700 Message-Id: <3.0.3.32.20010815205337.00758e3c@mail.schaik.com> X-Sender: willemschaik@mail.schaik.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Date: Wed, 15 Aug 2001 20:53:37 -0600 To: PNG Implementation List From: Willem van Schaik Subject: RE: pnmtopng broken In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by ccrc.wustl.edu id f7G2rw416548 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Glenn mentioned already the possibility that you had transferred to another platform. But knowing the issues I had this week with GnuWin32 (solved by now), I think even more that maybe you took the Unix binaries and just compiled them with GnuWin32 without setting the HAVE_SETMODE variable in one of your header files. In summary, Glenn is 100% right that you have a DOS-Unix problem, but given that you compile on a Cygwin platform, I suspect more a problem with the way you build your code. Willem At 16:23 15-08-01 -0700, you wrote: >I am running on Cygwin platform, using libpng 1.0.11 >I tried 9.14, it produced the same (bad) result. > >I also did a binary dump of the png files, and here's what I found: > >The 'good' file, i.e. my original png file looks like this: >------------------------------------------------------ > [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789012345] >00000: 89 50 4E 47 0D 0A 1A 0A 00 00 00 0D 49 48 44 52 |ëPNG........IHDR| >00016: 00 00 02 D0 00 00 02 1C 08 02 00 00 00 50 1F 0E |..?-..??.?...P??| >00032: 04 00 00 00 01 73 52 47 42 00 AE CE 1C E9 00 00 |?...?sRGB.«+?T..| >00048: 00 09 70 48 59 73 00 00 0B 13 00 00 0B 13 01 00 |..pHYs..??..???.| >00064: 9A 9C 18 00 00 C2 EF 49 44 41 54 78 5E ED BD 07 |Ü£?..-nIDATx^f+.| > > >The 'bad' file, as generated by pnmtopng, looks like this: >------------------------------------------------------ > [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789012345] >00000: 89 50 4E 47 0D 0D 0A 1A 0D 0A 00 00 00 0D 49 48 |ëPNG..........IH| >00016: 44 52 00 00 02 D0 00 00 02 1C 08 02 00 00 00 50 |DR..?-..??.?...P| >00032: 1F 0E 04 00 00 20 00 49 44 41 54 78 9C EC BD 79 |???.. .IDATx£8+y| >00048: F4 25 47 75 26 78 DF AF 5E 95 76 09 B4 59 80 F6 |(%Gu&x¯»^òv.¦YÇ÷| >00064: 7D 45 FB 8A 2C 81 8C 19 CC 66 D6 B6 C7 7D E8 F1 |}Evè,üî?¦f+¦¦}F±| >00080: 8C A7 B1 19 2F DD 8D 1B 77 7B 61 F0 7A B0 DD B4 |?/¦ì?w{a=z¦¦¦| > > >Obviously the 'bad' file got a very strange header not confirming to the PNG >v1.0 standard, which requires the first 8 bytes to be "89 50 4E 47 0D 0A 1A >0A", not the funny one generated. > >cheers, > >Eric > > > >-----Original Message----- >From: Willem van Schaik [mailto:willem@schaik.com] >Sent: Wednesday, August 15, 2001 3:51 PM >To: PNG Implementation List >Subject: RE: pnmtopng broken > > >Hi Eric, > >Few questions: what platform did you build pnmtopng? Which libpng version? >Did earlier versions like 9.14/9.15 work OK for you? > >Willem > > >-- Original Message -- > >>I am using netpbm 9.16. >> >>My problem is the png image this tool produced seems to be corrupted. I >have >>run through pngcheck and verified. >> >>Anyone got this "pnmtopng" working? >> >>eric >> >> >>-----Original Message----- >>From: Willem van Schaik [mailto:willem@schaik.com] >>Sent: Tuesday, August 14, 2001 6:56 PM >>To: PNG Implementation List >>Subject: Re: Open source for resizing png files >> >> >>Yes, look at the sourcecode of pnmscale. Part of "netpbm", which project >>can be found at "http://www.sourceforge.net/projects/netpbm". >> >>Willem >> >> >> >>At 18:22 14-08-01 -0700, you wrote: >>>Anyone knows of any open source code for resizing (especially reducing) >>png >>>files? >>> >>>Eric >>> >>> >>>-- >>>Send the message body "help" to png-implement-request@ccrc.wustl.edu >>> >> >> >>-- >>Send the message body "help" to png-implement-request@ccrc.wustl.edu >> >>-- >>Send the message body "help" to png-implement-request@ccrc.wustl.edu >> > >v a n S c h a i k >------------------------------------------------------------------------ >Willem van Schaik willem@schaik.com > > > > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 16 11:09:41 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id LAA27268 for ; Thu, 16 Aug 2001 11:09:41 -0500 (CDT) Received: by webshld.ccf.swri.edu; id LAA12613; Thu, 16 Aug 2001 11:07:35 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA6OaaJy; Thu, 16 Aug 01 11:07:00 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7GG11S18998 for ; Thu, 16 Aug 2001 11:01:11 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7GG6wg28156; Thu, 16 Aug 2001 11:06:58 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from himalaya.etrieve.com (mail.etrieve.com [198.107.63.171]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7GG6v428152 for ; Thu, 16 Aug 2001 11:06:57 -0500 (CDT) Received: by HIMALAYA with Internet Mail Service (5.5.2653.19) id ; Thu, 16 Aug 2001 09:00:38 -0700 Message-ID: From: Eric Fu To: PNG Implementation List Subject: RE: pnmtopng broken Date: Thu, 16 Aug 2001 09:00:28 -0700 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by ccrc.wustl.edu id f7GG6v428153 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List First, it's not FTP related. There's no file transfer going on. Second, it's certainly a problem with the way the program is built, but where? The first time you run a "make" on netpbm, it asks you what system you are building on, and cywin is certainly one of the options (7, to be specific), hence the possible culprit lays on libpng. Any ideas where it might go wrong? Eric -----Original Message----- From: Willem van Schaik [mailto:willem@schaik.com] Sent: Wednesday, August 15, 2001 7:54 PM To: PNG Implementation List Subject: RE: pnmtopng broken Glenn mentioned already the possibility that you had transferred to another platform. But knowing the issues I had this week with GnuWin32 (solved by now), I think even more that maybe you took the Unix binaries and just compiled them with GnuWin32 without setting the HAVE_SETMODE variable in one of your header files. In summary, Glenn is 100% right that you have a DOS-Unix problem, but given that you compile on a Cygwin platform, I suspect more a problem with the way you build your code. Willem At 16:23 15-08-01 -0700, you wrote: >I am running on Cygwin platform, using libpng 1.0.11 >I tried 9.14, it produced the same (bad) result. > >I also did a binary dump of the png files, and here's what I found: > >The 'good' file, i.e. my original png file looks like this: >------------------------------------------------------ > [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789012345] >00000: 89 50 4E 47 0D 0A 1A 0A 00 00 00 0D 49 48 44 52 |ëPNG........IHDR| >00016: 00 00 02 D0 00 00 02 1C 08 02 00 00 00 50 1F 0E |..?-..??.?...P??| >00032: 04 00 00 00 01 73 52 47 42 00 AE CE 1C E9 00 00 |?...?sRGB.«+?T..| >00048: 00 09 70 48 59 73 00 00 0B 13 00 00 0B 13 01 00 |..pHYs..??..???.| >00064: 9A 9C 18 00 00 C2 EF 49 44 41 54 78 5E ED BD 07 |Ü£?..-nIDATx^f+.| > > >The 'bad' file, as generated by pnmtopng, looks like this: >------------------------------------------------------ > [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789012345] >00000: 89 50 4E 47 0D 0D 0A 1A 0D 0A 00 00 00 0D 49 48 |ëPNG..........IH| >00016: 44 52 00 00 02 D0 00 00 02 1C 08 02 00 00 00 50 |DR..?-..??.?...P| >00032: 1F 0E 04 00 00 20 00 49 44 41 54 78 9C EC BD 79 |???.. .IDATx£8+y| >00048: F4 25 47 75 26 78 DF AF 5E 95 76 09 B4 59 80 F6 |(%Gu&x¯»^òv.¦YÇ÷| >00064: 7D 45 FB 8A 2C 81 8C 19 CC 66 D6 B6 C7 7D E8 F1 |}Evè,üî?¦f+¦¦}F±| >00080: 8C A7 B1 19 2F DD 8D 1B 77 7B 61 F0 7A B0 DD B4 |?/¦ì?w{a=z¦¦¦| > > >Obviously the 'bad' file got a very strange header not confirming to the PNG >v1.0 standard, which requires the first 8 bytes to be "89 50 4E 47 0D 0A 1A >0A", not the funny one generated. > >cheers, > >Eric > > > >-----Original Message----- >From: Willem van Schaik [mailto:willem@schaik.com] >Sent: Wednesday, August 15, 2001 3:51 PM >To: PNG Implementation List >Subject: RE: pnmtopng broken > > >Hi Eric, > >Few questions: what platform did you build pnmtopng? Which libpng version? >Did earlier versions like 9.14/9.15 work OK for you? > >Willem > > >-- Original Message -- > >>I am using netpbm 9.16. >> >>My problem is the png image this tool produced seems to be corrupted. I >have >>run through pngcheck and verified. >> >>Anyone got this "pnmtopng" working? >> >>eric >> >> >>-----Original Message----- >>From: Willem van Schaik [mailto:willem@schaik.com] >>Sent: Tuesday, August 14, 2001 6:56 PM >>To: PNG Implementation List >>Subject: Re: Open source for resizing png files >> >> >>Yes, look at the sourcecode of pnmscale. Part of "netpbm", which project >>can be found at "http://www.sourceforge.net/projects/netpbm". >> >>Willem >> >> >> >>At 18:22 14-08-01 -0700, you wrote: >>>Anyone knows of any open source code for resizing (especially reducing) >>png >>>files? >>> >>>Eric >>> >>> >>>-- >>>Send the message body "help" to png-implement-request@ccrc.wustl.edu >>> >> >> >>-- >>Send the message body "help" to png-implement-request@ccrc.wustl.edu >> >>-- >>Send the message body "help" to png-implement-request@ccrc.wustl.edu >> > >v a n S c h a i k >------------------------------------------------------------------------ >Willem van Schaik willem@schaik.com > > > > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 16 11:10:55 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id LAA27280 for ; Thu, 16 Aug 2001 11:10:55 -0500 (CDT) Received: by webshld.ccf.swri.edu; id LAA12834; Thu, 16 Aug 2001 11:08:50 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAVbaG_y; Thu, 16 Aug 01 11:08:19 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7GG2KS19043 for ; Thu, 16 Aug 2001 11:02:31 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7GG8gN28210; Thu, 16 Aug 2001 11:08:42 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from himalaya.etrieve.com (mail.etrieve.com [198.107.63.171]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7GG8f428205 for ; Thu, 16 Aug 2001 11:08:41 -0500 (CDT) Received: by HIMALAYA with Internet Mail Service (5.5.2653.19) id ; Thu, 16 Aug 2001 09:02:25 -0700 Message-ID: From: Eric Fu To: PNG Implementation List Subject: RE: pnmtopng broken Date: Thu, 16 Aug 2001 09:01:57 -0700 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by ccrc.wustl.edu id f7GG8g428207 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List BTW, I am using libpng 1.0.12 now, still having the same problem. Eric -----Original Message----- From: Willem van Schaik [mailto:willem@schaik.com] Sent: Wednesday, August 15, 2001 7:54 PM To: PNG Implementation List Subject: RE: pnmtopng broken Glenn mentioned already the possibility that you had transferred to another platform. But knowing the issues I had this week with GnuWin32 (solved by now), I think even more that maybe you took the Unix binaries and just compiled them with GnuWin32 without setting the HAVE_SETMODE variable in one of your header files. In summary, Glenn is 100% right that you have a DOS-Unix problem, but given that you compile on a Cygwin platform, I suspect more a problem with the way you build your code. Willem At 16:23 15-08-01 -0700, you wrote: >I am running on Cygwin platform, using libpng 1.0.11 >I tried 9.14, it produced the same (bad) result. > >I also did a binary dump of the png files, and here's what I found: > >The 'good' file, i.e. my original png file looks like this: >------------------------------------------------------ > [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789012345] >00000: 89 50 4E 47 0D 0A 1A 0A 00 00 00 0D 49 48 44 52 |ëPNG........IHDR| >00016: 00 00 02 D0 00 00 02 1C 08 02 00 00 00 50 1F 0E |..?-..??.?...P??| >00032: 04 00 00 00 01 73 52 47 42 00 AE CE 1C E9 00 00 |?...?sRGB.«+?T..| >00048: 00 09 70 48 59 73 00 00 0B 13 00 00 0B 13 01 00 |..pHYs..??..???.| >00064: 9A 9C 18 00 00 C2 EF 49 44 41 54 78 5E ED BD 07 |Ü£?..-nIDATx^f+.| > > >The 'bad' file, as generated by pnmtopng, looks like this: >------------------------------------------------------ > [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789012345] >00000: 89 50 4E 47 0D 0D 0A 1A 0D 0A 00 00 00 0D 49 48 |ëPNG..........IH| >00016: 44 52 00 00 02 D0 00 00 02 1C 08 02 00 00 00 50 |DR..?-..??.?...P| >00032: 1F 0E 04 00 00 20 00 49 44 41 54 78 9C EC BD 79 |???.. .IDATx£8+y| >00048: F4 25 47 75 26 78 DF AF 5E 95 76 09 B4 59 80 F6 |(%Gu&x¯»^òv.¦YÇ÷| >00064: 7D 45 FB 8A 2C 81 8C 19 CC 66 D6 B6 C7 7D E8 F1 |}Evè,üî?¦f+¦¦}F±| >00080: 8C A7 B1 19 2F DD 8D 1B 77 7B 61 F0 7A B0 DD B4 |?/¦ì?w{a=z¦¦¦| > > >Obviously the 'bad' file got a very strange header not confirming to the PNG >v1.0 standard, which requires the first 8 bytes to be "89 50 4E 47 0D 0A 1A >0A", not the funny one generated. > >cheers, > >Eric > > > >-----Original Message----- >From: Willem van Schaik [mailto:willem@schaik.com] >Sent: Wednesday, August 15, 2001 3:51 PM >To: PNG Implementation List >Subject: RE: pnmtopng broken > > >Hi Eric, > >Few questions: what platform did you build pnmtopng? Which libpng version? >Did earlier versions like 9.14/9.15 work OK for you? > >Willem > > >-- Original Message -- > >>I am using netpbm 9.16. >> >>My problem is the png image this tool produced seems to be corrupted. I >have >>run through pngcheck and verified. >> >>Anyone got this "pnmtopng" working? >> >>eric >> >> >>-----Original Message----- >>From: Willem van Schaik [mailto:willem@schaik.com] >>Sent: Tuesday, August 14, 2001 6:56 PM >>To: PNG Implementation List >>Subject: Re: Open source for resizing png files >> >> >>Yes, look at the sourcecode of pnmscale. Part of "netpbm", which project >>can be found at "http://www.sourceforge.net/projects/netpbm". >> >>Willem >> >> >> >>At 18:22 14-08-01 -0700, you wrote: >>>Anyone knows of any open source code for resizing (especially reducing) >>png >>>files? >>> >>>Eric >>> >>> >>>-- >>>Send the message body "help" to png-implement-request@ccrc.wustl.edu >>> >> >> >>-- >>Send the message body "help" to png-implement-request@ccrc.wustl.edu >> >>-- >>Send the message body "help" to png-implement-request@ccrc.wustl.edu >> > >v a n S c h a i k >------------------------------------------------------------------------ >Willem van Schaik willem@schaik.com > > > > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > >-- >Send the message body "help" to png-implement-request@ccrc.wustl.edu > -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 16 14:14:03 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id OAA28811 for ; Thu, 16 Aug 2001 14:14:03 -0500 (CDT) Received: by webshld.ccf.swri.edu; id OAA12744; Thu, 16 Aug 2001 14:12:08 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAGya44y; Thu, 16 Aug 01 14:12:07 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7GJ73S29144 for ; Thu, 16 Aug 2001 14:07:03 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7GJDb003062; Thu, 16 Aug 2001 14:13:37 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail11.sdc1.sfba.home.com (femail11.sdc1.sfba.home.com [24.0.95.107]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7GJDa403058 for ; Thu, 16 Aug 2001 14:13:36 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail11.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010816191336.OFDQ17568.femail11.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com> for ; Thu, 16 Aug 2001 12:13:36 -0700 Message-Id: <3.0.6.32.20010816151112.00e0c710@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Thu, 16 Aug 2001 15:11:12 -0400 To: PNG Implementation List From: Glenn Randers-Pehrson Subject: RE: pnmtopng broken In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 09:00 AM 8/16/01 -0700, Eric Fu wrote: >First, it's not FTP related. There's no file transfer going on. > >Second, it's certainly a problem with the way the program is built, but >where? > >The first time you run a "make" on netpbm, it asks you what system you are >building on, and cywin is certainly one of the options (7, to be specific), >hence the possible culprit lays on libpng. > >Any ideas where it might go wrong? Did you define HAVE_SETMODE and O_BINARY as mentioned in pm_config.h? Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 16 16:21:41 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id QAA29887 for ; Thu, 16 Aug 2001 16:21:41 -0500 (CDT) Received: by webshld.ccf.swri.edu; id QAA05085; Thu, 16 Aug 2001 16:19:46 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAi9ai7j; Thu, 16 Aug 01 16:19:45 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7GLEeS06108 for ; Thu, 16 Aug 2001 16:14:41 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7GLLGh07656; Thu, 16 Aug 2001 16:21:16 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from himalaya.etrieve.com (mail.etrieve.com [198.107.63.171]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7GLLE407632 for ; Thu, 16 Aug 2001 16:21:14 -0500 (CDT) Received: by HIMALAYA with Internet Mail Service (5.5.2653.19) id ; Thu, 16 Aug 2001 14:14:58 -0700 Message-ID: From: Eric Fu To: PNG Implementation List Subject: RE: pnmtopng broken Date: Thu, 16 Aug 2001 14:14:58 -0700 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Setting HAVE_SETMODE seemed to fix the problem. Better make it a note or in the configure tool for cygwin port. Thanks for the help. eric -----Original Message----- From: Glenn Randers-Pehrson [mailto:glennrp@home.com] Sent: Thursday, August 16, 2001 12:11 PM To: PNG Implementation List Subject: RE: pnmtopng broken At 09:00 AM 8/16/01 -0700, Eric Fu wrote: >First, it's not FTP related. There's no file transfer going on. > >Second, it's certainly a problem with the way the program is built, but >where? > >The first time you run a "make" on netpbm, it asks you what system you are >building on, and cywin is certainly one of the options (7, to be specific), >hence the possible culprit lays on libpng. > >Any ideas where it might go wrong? Did you define HAVE_SETMODE and O_BINARY as mentioned in pm_config.h? Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Thu Aug 16 20:13:31 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id UAA02356 for ; Thu, 16 Aug 2001 20:13:31 -0500 (CDT) Received: by webshld.ccf.swri.edu; id UAA27579; Thu, 16 Aug 2001 20:11:36 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAA_aq31; Thu, 16 Aug 01 20:11:35 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7H16US15056 for ; Thu, 16 Aug 2001 20:06:30 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7H1AUd22415; Thu, 16 Aug 2001 20:10:30 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f7H1AT422411 for ; Thu, 16 Aug 2001 20:10:29 -0500 (CDT) Received: (qmail 8403 invoked from network); 17 Aug 2001 01:10:34 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 17 Aug 2001 01:10:34 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f7H18DC26425 for png-implement@ccrc.wustl.edu; Thu, 16 Aug 2001 18:08:13 -0700 Date: Thu, 16 Aug 2001 18:08:13 -0700 Message-Id: <200108170108.f7H18DC26425@sonic.net> From: Greg Roelofs To: png-implement@ccrc.wustl.edu Subject: RE: pnmtopng broken Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List Eric Fu wrote: > Setting HAVE_SETMODE seemed to fix the problem. > Better make it a note or in the configure tool for cygwin port. I've added the same macro to the non-NetPBM-9.x version I maintain (both stdin and stdout, pnmtopng and pngtopnm): #ifdef HAVE_SETMODE /* DOS, FlexOS, Human68k, NetWare, OS/2, Win32 */ # if (defined(__HIGHC__) && !defined(FLEXOS)) setmode(stdout, _BINARY); # else setmode(1, O_BINARY); /* some buggy C libraries require BOTH setmode() */ # endif /* call AND the fdopen() in binary mode :-( */ #endif #ifdef RISCOS ofp = stdout; #else if ((ofp = fdopen(1, "wb")) == (FILE *)NULL) pm_error ("cannot write to stdout"); #endif This, together with a patch from TenThumbs to make text-chunk-file handling more robust (buffer overrun), will show up as 2.37.7 at some point in the not-too-distant (but not immediate) future. Greg -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Fri Aug 17 02:14:16 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id CAA03731 for ; Fri, 17 Aug 2001 02:14:16 -0500 (CDT) Received: by webshld.ccf.swri.edu; id CAA15223; Fri, 17 Aug 2001 02:12:20 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAGraWUD; Fri, 17 Aug 01 02:12:20 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7H77GS25320 for ; Fri, 17 Aug 2001 02:07:16 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7H7DAG26855; Fri, 17 Aug 2001 02:13:10 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from mail.san.yahoo.com (mail.san.yahoo.com [209.132.1.30]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7H7D8426851 for ; Fri, 17 Aug 2001 02:13:09 -0500 (CDT) Received: from volans (24.67.95.214) by mail.san.yahoo.com (5.5.041.1) id 3B797881000BA972 for png-implement@ccrc.wustl.edu; Fri, 17 Aug 2001 00:10:21 -0700 Message-Id: <3.0.3.32.20010817011100.0074c978@mail.schaik.com> X-Sender: willemschaik@mail.schaik.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Date: Fri, 17 Aug 2001 01:11:00 -0600 To: PNG Implementation List From: Willem van Schaik Subject: RE: pnmtopng broken In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 14:14 16-08-01 -0700, Eric Fu wrote: >Setting HAVE_SETMODE seemed to fix the problem. >Better make it a note or in the configure tool for cygwin port. > I told you: | I think even more that maybe you took the Unix binaries and just | compiled them with GnuWin32 without setting the HAVE_SETMODE variable in | one of your header files. Better next time post a bit less and try a bit more .... Willem -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Mon Aug 20 10:34:03 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id KAA20967 for ; Mon, 20 Aug 2001 10:34:03 -0500 (CDT) Received: by webshld.ccf.swri.edu; id KAA24783; Mon, 20 Aug 2001 10:32:04 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAODaqzW; Mon, 20 Aug 01 10:32:02 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7KFQsS28902 for ; Mon, 20 Aug 2001 10:26:54 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7KFVgV28853; Mon, 20 Aug 2001 10:31:42 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f7KFVf428848 for ; Mon, 20 Aug 2001 10:31:41 -0500 (CDT) Received: (qmail 23842 invoked from network); 20 Aug 2001 15:31:38 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 20 Aug 2001 15:31:38 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.0/8.7.3) id f7KFTBn00963 for png-implement@ccrc.wustl.edu; Mon, 20 Aug 2001 08:29:11 -0700 Received: from web10803.mail.yahoo.com (web10803.mail.yahoo.com [216.136.130.245]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f7KD2B426013 for ; Mon, 20 Aug 2001 08:02:11 -0500 (CDT) Message-ID: <20010820130213.7027.qmail@web10803.mail.yahoo.com> Received: from [210.235.154.3] by web10803.mail.yahoo.com; Mon, 20 Aug 2001 06:02:13 PDT Date: Mon, 20 Aug 2001 06:02:13 -0700 (PDT) From: mpkid Subject: Re: A serious png problem To: Greg Roelofs Cc: png-implement@ccrc.wustl.edu In-Reply-To: <200107221624.f6MGOTq08212@sonic.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List [non-member submission] Hi! I'm still trying out the png stuff today. ;) Your advise is deeply needed and appreciated. > if that's what you mean. They use standard libpng > functions to request > down-conversion to 8bps, then display normally. I dont quite get this sentenace above. So, if I save an image with 8 bits/channcel info compare with a 16 bits per channel info. They'll both gonna display similarly isnt it? In fact, they will display exactly the same?! So, what's the point of saving 16 bit of info when it has to be down converted to 8 bits when in use? Thank you v. much!!! --- Greg Roelofs wrote: > > I managed to write some codes to read/write png in > 8 > > bits grayscale and 24 bit color. But when I try 16 > > bits grayscale or 48 bits color. Nothing works. > The > > examples that came none has anything on > 16bit/channel > > example. > > The rpng and rpng2 examples in contrib/gregbook will > correctly display > 16bps images (e.g., > http://www.libmng.com/pub/png/pngvrml/ct2.9-128x128.png), > if that's what you mean. They use standard libpng > functions to request > down-conversion to 8bps, then display normally. > > > I cant see any way of writing a 16 bit info > > when the write_image or write_row functions, etc. > are > > all taking byte as input function argument. > > Two bytes == 16 bits, right? The "Writing" section > of libpng.txt seems > fairly clear: > > PNG files store 16 bit pixels in network byte > order (big-endian, > ie. most significant bits first). This code > would be used if they are > supplied the other way (little-endian, i.e. > least significant bits > first, the way PCs store them): > > if (bit_depth > 8) > png_set_swap(png_ptr); > > > I tested a > > 48 bit png image from the png website using the > test > > example given, > > pngtest? It read and wrote an identical version of > PngSuite/tbbn2c16.png > for me... > > > it generate errors while all > > 8bit/channel images are perfect?!? I've lost quite > a > > bit of sanity on this. So any help or some simple > > pointers will be v. appreciated. :) > > I'd suggest you send a message to > png-implement@ccrc.wustl.edu, maybe > with some sample code that isn't working, and see if > someone can help. > You could also look at the pnmtopng source code, > since it can write > 16bps PNGs, but it's also got gobs of other stuff > and is fairly complex. > > Regards, > -- > Greg Roelofs newt@pobox.com > http://pobox.com/~newt/ > Newtware, PNG Group, Info-ZIP, Philips > Semiconductors, ... __________________________________________________ Do You Yahoo!? Make international calls for as low as $.04/minute with Yahoo! Messenger http://phonecard.yahoo.com/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Mon Aug 20 11:21:32 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id LAA21328 for ; Mon, 20 Aug 2001 11:21:32 -0500 (CDT) Received: by webshld.ccf.swri.edu; id LAA03791; Mon, 20 Aug 2001 11:19:33 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAATyaWzh; Mon, 20 Aug 01 11:19:33 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7KGEQS01322 for ; Mon, 20 Aug 2001 11:14:26 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7KGLLQ29999; Mon, 20 Aug 2001 11:21:21 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail8.sdc1.sfba.home.com (femail8.sdc1.sfba.home.com [24.0.95.88]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7KGLL429993 for ; Mon, 20 Aug 2001 11:21:21 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail8.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010820162118.IZLI2935.femail8.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com>; Mon, 20 Aug 2001 09:21:18 -0700 Message-Id: <3.0.6.32.20010820121852.00e64cb0@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Mon, 20 Aug 2001 12:18:52 -0400 To: PNG Implementation List From: Glenn Randers-Pehrson Subject: Re: A serious png problem Cc: mp4kid@yahoo.com In-Reply-To: <20010820130213.7027.qmail@web10803.mail.yahoo.com> References: <200107221624.f6MGOTq08212@sonic.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List At 06:02 AM 8/20/01 -0700, mpkid wrote: >[non-member submission] > >Hi! >I'm still trying out the png stuff today. ;) >Your advise is deeply needed and appreciated. > >> if that's what you mean. They use standard libpng >> functions to request >> down-conversion to 8bps, then display normally. > >I dont quite get this sentenace above. So, if I save >an image with 8 bits/channcel info compare with a 16 >bits per channel info. They'll both gonna display >similarly isnt it? In fact, they will display exactly >the same?! Yes, if you display them both on an 8-bit output device or if you use an 8-bit application to view them. >So, what's the point of saving 16 bit of >info when it has to be down converted to 8 bits when >in use? It doesn't have to be down converted. If you display it on a greater-than-8-bit device and with a greater-than-8-bit application, then you'll see differences. Or, even with 8-bit apps and 8-bit output devices, your app could increase contrast to bring out details (e.g., by adjusting gamma). If you've already stored the image in 8-bit format, there is no detail to bring out. Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sat Aug 25 08:00:56 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id IAA11604 for ; Sat, 25 Aug 2001 08:00:56 -0500 (CDT) Received: by webshld.ccf.swri.edu; id HAA11843; Sat, 25 Aug 2001 07:58:53 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAWRaqix; Sat, 25 Aug 01 07:58:53 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7PCriM15472 for ; Sat, 25 Aug 2001 07:53:44 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7PCvQs19710; Sat, 25 Aug 2001 07:57:26 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f7PCvP419706 for ; Sat, 25 Aug 2001 07:57:25 -0500 (CDT) Received: (qmail 31273 invoked from network); 25 Aug 2001 12:57:27 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 25 Aug 2001 12:57:27 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.6/8.7.3) id f7PCsqB10188 for png-implement@ccrc.wustl.edu; Sat, 25 Aug 2001 05:54:52 -0700 Received: from web10802.mail.yahoo.com (web10802.mail.yahoo.com [216.136.130.244]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f7P0ih411764 for ; Fri, 24 Aug 2001 19:44:44 -0500 (CDT) Message-ID: <20010825004451.84910.qmail@web10802.mail.yahoo.com> Received: from [210.20.46.75] by web10802.mail.yahoo.com; Fri, 24 Aug 2001 17:44:51 PDT Date: Fri, 24 Aug 2001 17:44:51 -0700 (PDT) From: mpkid Subject: Thank you [was Re: A serious png problem] To: Glenn Randers-Pehrson , PNG Implementation List In-Reply-To: <3.0.6.32.20010820121852.00e64cb0@netmail.home.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List [non-member submission] Hi. I just wanna say thank you v. much for the timely replies. I finally got tha png format done. [it's been a while] Now i can render my images in png format! I'm just too glad. :) [The only thing is I still dunno what devices can take advantage of the 16 bit channel.(?)] Thank you! --- Glenn Randers-Pehrson wrote: > At 06:02 AM 8/20/01 -0700, mpkid wrote: > >[non-member submission] > > > >Hi! > >I'm still trying out the png stuff today. ;) > >Your advise is deeply needed and appreciated. > > > >> if that's what you mean. They use standard > libpng > >> functions to request > >> down-conversion to 8bps, then display normally. > > > >I dont quite get this sentenace above. So, if I > save > >an image with 8 bits/channcel info compare with a > 16 > >bits per channel info. They'll both gonna display > >similarly isnt it? In fact, they will display > exactly > >the same?! > > Yes, if you display them both on an 8-bit output > device or > if you use an 8-bit application to view them. > > >So, what's the point of saving 16 bit of > >info when it has to be down converted to 8 bits > when > >in use? > > It doesn't have to be down converted. > > If you display it on a greater-than-8-bit device > and with a greater-than-8-bit application, then > you'll see > differences. Or, even with 8-bit apps and 8-bit > output devices, > your app could increase contrast to bring out > details (e.g., by > adjusting gamma). If you've already stored the > image in 8-bit format, > there is no detail to bring out. > > Glenn __________________________________________________ Do You Yahoo!? Make international calls for as low as $.04/minute with Yahoo! Messenger http://phonecard.yahoo.com/ -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Sat Aug 25 11:14:16 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id LAA12163 for ; Sat, 25 Aug 2001 11:14:16 -0500 (CDT) Received: by webshld.ccf.swri.edu; id LAA18133; Sat, 25 Aug 2001 11:12:13 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAA6NaGAJ; Sat, 25 Aug 01 11:12:12 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7PG73M19317 for ; Sat, 25 Aug 2001 11:07:03 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7PGDlM21870; Sat, 25 Aug 2001 11:13:47 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from femail20.sdc1.sfba.home.com (femail20.sdc1.sfba.home.com [24.0.95.129]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7PGDl421866 for ; Sat, 25 Aug 2001 11:13:47 -0500 (CDT) Received: from cc170083-a.abdn1.md.home.com ([24.7.161.22]) by femail20.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20010825161350.EWOM19777.femail20.sdc1.sfba.home.com@cc170083-a.abdn1.md.home.com> for ; Sat, 25 Aug 2001 09:13:50 -0700 Message-Id: <3.0.6.32.20010825121123.00e802f0@netmail.home.com> X-Sender: glennrp@netmail.home.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Sat, 25 Aug 2001 12:11:23 -0400 To: png-implement@ccrc.wustl.edu From: Glenn Randers-Pehrson Subject: libpng-1.2.0rc1 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List libpng-1.2.0rc1 is available for download from http://libpng.sf.net and from ftp://swrinde.nde.swri.edu/pub/png-group/src/ This is the "release candidate" for libpng-1.2.0. Glenn -- Send the message body "help" to png-implement-request@ccrc.wustl.edu From owner-png-implement@ccrc.wustl.edu Tue Aug 28 10:33:27 2001 Received: from webshld.ccf.swri.edu (webshld.ccf.swri.edu [129.162.252.34]) by swrinde.nde.swri.edu (8.9.3/8.9.3) with ESMTP id KAA00970 for ; Tue, 28 Aug 2001 10:33:26 -0500 (CDT) Received: by webshld.ccf.swri.edu; id KAA20434; Tue, 28 Aug 2001 10:31:20 -0500 (CDT) Received: from mailhub.ccf.swri.edu(129.162.1.33) by webshld.webshld.ccf.swri.edu via csmap (V4.1) id srcAAAUSa44N; Tue, 28 Aug 01 10:31:18 -0500 Received: from ccrc.wustl.edu (dns.ccrc.wustl.edu [128.252.169.100]) by mailhub.ccf.swri.edu (8.11.2/8.11.2) with ESMTP id f7SFQ7o20758 for ; Tue, 28 Aug 2001 10:26:07 -0500 (CDT) Received: (from majordom@localhost) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) id f7SFTsr29286; Tue, 28 Aug 2001 10:29:54 -0500 (CDT) X-Authentication-Warning: ccrc.wustl.edu: majordom set sender to owner-png-implement@ccrc.wustl.edu using -f Received: from marine.sonic.net (marine.sonic.net [208.201.224.37]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with SMTP id f7SFTr429282 for ; Tue, 28 Aug 2001 10:29:53 -0500 (CDT) Received: (qmail 13900 invoked from network); 28 Aug 2001 15:29:48 -0000 Received: from bolt.sonic.net (HELO sonic.net) (208.201.224.36) by marine.sonic.net with SMTP; 28 Aug 2001 15:29:48 -0000 Received: (from roelofs@localhost) by sonic.net (8.11.6/8.7.3) id f7SFR8O06760 for png-implement@ccrc.wustl.edu; Tue, 28 Aug 2001 08:27:08 -0700 Received: from australis.intranet (ns1.electrosilk.net [203.31.40.1]) by ccrc.wustl.edu (8.10.2+Sun/8.10.2) with ESMTP id f7SEL0427795 for ; Tue, 28 Aug 2001 09:21:02 -0500 (CDT) Received: from ws8 (ws8.electrosilk.net [203.31.40.8]) by australis.intranet (8.9.3/8.9.3) with SMTP id WAA11791 for ; Tue, 28 Aug 2001 22:21:01 +0800 Message-ID: <022901c12fcc$a3c1b760$08281fcb@electrosilk.net> From: "Jeremy" To: "PNG Implementation List" References: <3.0.3.32.20010805005409.0075dfb4@mail.schaik.com> Subject: Anti-Aliasing Date: Tue, 28 Aug 2001 22:20:50 +0800 MIME-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Sender: owner-png-implement@ccrc.wustl.edu Precedence: bulk Reply-To: PNG Implementation List [non-member submission] Hi, Is there any easy way to anti-alias an image when converting it to PNG? Jeremy -- Send the message body "help" to png-implement-request@ccrc.wustl.edu