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by byearthithatius 303 days ago
I downloaded the image he provided (https://www.dpreview.com/sample-galleries/4949897610/pentax-...)

The DNG file did have the 01 byte at `2FD00` (from xxd or hexdump -C). However it didn't have a byte position `3E40B`. I tried searching and there is literally no entry at that position. I found a 02 value at 3e40 but not at 3e40b. Is this a typo?

Where did you find it to try and repro?

1 comments

You need to click the link that says "RAW (33.0MB)". The filename should be "IMGP0847.DNG".
Thanks immensely. Very important detail,

Did you find a 02 at 3E40B? I found 01 at 2FD00, but there was no 3E40B byte position entry.

I did find something similar at 00003e40: 00003e40 02 00 04 00 0a 00 00 00 30 01 00 00 00 00 00 00 |........0.......|

Yes:

  dd status=none if=IMGP0847.DNG bs=1 skip=0x3e40b count=1 | xxd
  00000000: 02
Thanks! You are correct, when I did a dump with `xxd IMGP0847.DNG > output.hex` it wasn't showing up for some reason.... But your command worked (though my dd doesn't like hex values so I needed to get decimal via printf "%d\n" 0x3E40B).

Curious if you (clearly smarter than me) know why it didn't show correctly in the xxd or hexdump for the file. Would love to learn.

  xxd IMGP0847.DNG | grep 03e400:
  0003e400: ffd8 ffc3 000e 0e10 800c 5002 0011 0001  ..........P.....
Look at the byte at offset 11 (0xb), it's there.
Ohhh the b offset (11) is an offset _on that line_ (0003e400)! I got it now:D This thread taught me a great deal. Thank you, MajesticHobo2!