Re: EXIF support in PNG [was: Modern compressor]
"Soni L." <[email protected]>
| Newsgroups | gmane.comp.graphics.png.general |
|---|---|
| Message-ID | <[email protected]> |
On 01/01/17 12:22 AM, John Bowler wrote: > On Sat, Dec 31, 2016 at 2:57 PM, Glenn Randers-Pehrson > <[email protected] <mailto:[email protected]>> wrote: > > -rw-rw-r-- 1 glennrp glennrp 53679 Dec 31 17:45 51.exif > -rw-rw-r-- 1 glennrp glennrp 27936 Dec 31 17:45 51.exif.gz > -rw-rw-r-- 1 glennrp glennrp 31355 Dec 31 17:43 51.png.0005.zTXt > > I wouldn't give up compression. > > > Then you are going to throw the baby out with the bath water by > specifying a chunk that is not going to get used because of the simple > fact that most distros are stuck with a PNG decompressor which is not > being enhanced; e.g. Ubuntu which is stuck at libpng 1.2. > > Anyway, this is a matter for JEITA; they control the format, camera > manufacturers embed it in JPEG uncompressed. If it was an issue for > them they would compress it. Indeed, they have their own proposal > mechanism for enhancements; compression is effectively an EXIF > enhancement, PNG should not be doing it . The only place this data > comes from so far as I can see is a camera (but that means it is > pretty common.) > > And, indeed, you have argued with me that I should not use iTXt in the > test PNG files distributed with recent (iTXt supporting) libpng > releases because iTXt isn't commonly supported! > > What I'm suggesting instantly adds EXIF support to any existing PNG > implementation that supports returning the data of an unknown chunk to > the application. Instant, now, not 10 years or more in the future. > > [snip] > > John Bowler > > How much of this is actually relevant to day-to-day life and how much of this is politics? Doesn't PNG already have a way to shove metadata into it, including copyright information? How many different ways to convey the same information does a spec need to support before everyone using it is happy? Why do we need 20 different ways to describe copyright information in the PNG spec? We already have something that fits your use case. That it isn't well-supported just means you should push for it. ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ png-mng-misc mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/png-mng-misc