From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: To: 9fans@cse.psu.edu Subject: Re: [9fans] PNG and APE (cntd) Date: Thu, 27 Apr 2006 20:18:36 +0200 From: lucio@proxima.alt.za In-Reply-To: <33462a001ea97bcfca15659c3cb3607d@swtch.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Topicbox-Message-UUID: 488295ac-ead1-11e9-9d60-3106f5b1d025 > I remain unconvinced that all this effort on porting libpng > isn't wasted time. If the current png reading code doesn't > work, I'd rather see that improved. Andrey and I went through > it a year ago and made it pass all the tests in the PNG suite. Oh, the primary target is GeoTiff and the secondary one is Graphviz. I'm trying to produce a marked-up map of the area I live in and the format of the maps and aerial photographs I have sourced from the South African Surveyor General's office are in GeoTiff format. Since I needed zlib and libjpeg and GD wants libpng, it has been instructive to cut my teeth on npng. I had a recollection that png(1) did not do 24-bit images, but no proof, so I went ahead and started from a different end. I did discover that PNG isn't widely used, that the patent on LZW has expired and that I have plenty left to learn about graphics (thanks to all contributors, not least forsyth for the Microsoft papers - td's contribution does not need mention on this forum). As for Breadpng(), there's no ways I'm going to study the actual on-disk representation of PNG or any of the other formats without very sound reason. Life is way too short :-) That does not mean that I do not appreciate the value of doing it, or that I am not grateful to those who took it upon themselves to do it, of course. Philosophically, I'm at odds with the Plan 9 approach, but it's a pragmatic decision. ++L