Re: CALL for DISCUSSION: eXIf 20170115 -- length
Max Stepin <[email protected]>
| Newsgroups | gmane.comp.graphics.png.general |
|---|---|
| Message-ID | <CA+C1nqgp_s19nFno9pTOChMvMUws+Yp94eKMnZe5-MJFB-=_MQ@mail.gmail.com> |
> Images from my Nikon B700 contain a small thumbnail in the Exif data, and they also contain a larger preview with about 1Mpix -- it happens to be the same image that's shown on the viewfinder and onboard display screen. I haven't figured out exactly where it resides in the file; ImageMagick does not preserve it when copying the image. The second smaller JPEG begins after SOI of the first one (sometimes with padding in between, sometimes without). Most software would (rightfully) ignore it. Here I parsed two of my files: P8260540.JPG ------------ [0x 0] FFD8 [SOI] [0x 2] FFE1 [len=19525] [EXIF] th=[160x120] [0x 4C49] FFDB [len=197] [DQT] [0x 4D10] FFC4 [len=418] [DHT] [0x 4EB4] FFC0 [len=17] [SOF0] (Baseline) [3648x2736] [422] [0x 4EC7] FFDA [SOS] [0x 1E27E1] FFD9 [EOI] [0x 1E27E3] FFD8 [SOI] [0x 1E27E5] FFC4 [len=418] [DHT] [0x 1E2989] FFDB [len=132] [DQT] [0x 1E2A0F] FFC0 [len=17] [SOF0] (Baseline) [640x480] [422] [0x 1E2A22] FFDA [SOS] [0x 1F4649] FFD9 [EOI] P1000176.JPG ------------ [0x 0] FFD8 [SOI] [0x 2] FFE1 [len=33180] [EXIF] th=[160x120] [0x 81A0] FFE2 [len=96] [MPF] [0x 8202] FFDB [len=132] [DQT] [0x 8288] FFC0 [len=17] [SOF0] (Baseline) [2560x1920] [422] [0x 829B] FFC4 [len=418] [DHT] [0x 843F] FFDD [len=4] [DRI] [0x 8445] FFDA [SOS] [0x 12DF86] FFD9 [EOI] [0x 12E000] FFD8 [SOI] [0x 12E002] FFE1 [len=158] [EXIF] [0x 12E0A2] FFDB [len=132] [DQT] [0x 12E128] FFC0 [len=17] [SOF0] (Baseline) [1440x1080] [422] [0x 12E13B] FFC4 [len=418] [DHT] [0x 12E2DF] FFDD [len=4] [DRI] [0x 12E2E5] FFDA [SOS] [0x 1969AC] FFD9 [EOI] ------------------------------------------------------------------------------ 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