Re: [libpng:feature-requests] #32 Modern compressor
Glenn Randers-Pehrson <[email protected]>
| Newsgroups | gmane.comp.graphics.png.general |
|---|---|
| Message-ID | <CA+PdXcs9CXTibebhMCdA_Vgkpw5jPfWmvyh+-5KUryBK=XSS9A@mail.gmail.com> |
I forgot to mention how *Magick actually store the EXIF profile. In ImageMagick, it's here: chunk zTXt at offset 0x00078, length 31343, keyword: Raw profile type exif In GraphicsMagic, it's here: chunk zTXt at offset 0x00025, length 31365, keyword: Raw profile type EXIF I don't know who, when, or why the case of EXIF was changed to exif in ImageMagick. In either code, the zTXt chunk actually contains the raw profile, hex-encoded. The hex-encoding isn't a terribly efficient way of storing the data (I recall that Mark was horrified when I first proposed it), but the zTXt compression helps with that. Glenn ------------------------------------------------------------------------------ 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