Re: EXIF support in PNG
Willem van Schaik <[email protected]>
| Newsgroups | gmane.comp.graphics.png.general |
|---|---|
| Message-ID | <[email protected]> |
I took another photo from a Canon PowerShot and it showed "II" as the Endian type, so little Endian. Makes it interesting... The file starting with: ff d8 ff e1 1b f1 45 78 69 66 00 00 49 49 2a 00 |......Exif..II*.| The two length bytes show up in hexdump as "1bf1", which is 7153 (dec). Now running it through exiftool it says that the EXIF length is 7151. The JEITA spec shows that the 0xffe1 is part of the APP1 data, but it seems that according to exiftool it is not. We really have to resolve this, one way or the other !! For us is important, do we include the 0xffe1 marker in the EXIF chunk or not. Seeing this little endian JPEG, John was right that that 0x1bf1 is big indian, no matter the 'II' (little indian) showed lateron. When I go to line 00001bf0 in the file: 00001bf0 ff ff ff 00 00 ff db 00 84 00 01 01 01 01 01 02 so the APP1 seems to end with "ff ff ff" followed by "00 00" (which was in the previous image "ff d9"). For me "00 00" makes more sense than an EOI marker. Then followed by "ff db", the DQT marker which is the same as last time. Willem -- Willem van Schaik <[email protected]> http://www.schaik.com/ ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot