Remove segments before JFIF

[TheDoc]

HI,

hopefully this hasn't been answered before - but a search didn't turn up anything.

I have some software that adds its own segment into my jpgs before the JFIF segment. So the file looks like:

Standard jpg start

Code Select Expand


ff d8


Add. segment

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ff fe 20 64 65 6e 66 75 73 65 64 20 66 72 6f 6d 20 20 27 49 4d 47 5f 33 37 37 31 5f 45 4f 53 2e 4a 50 47 27 20 27 49 4d 47 5f 33 37 37 30 5f 45 4f 53 2e 4a 50 47 27 20 27 49 4d 47 5f 33 37 37 32 5f 45 4f 53 2e 4a 50 47 27 20 4c 56 20 72 61 6e 67 65 20 20 31 31 2e 37 20 20 31 32 2e 34 20 20 31 31 2e 30 20


JFIF segment

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ff e0 20 10 4a 46 49 46  ...


And now some other software can't read the image anymore.

Question: Is there any exiftool command that would allow to remove this additional segment? Unfortunately, I wasn't able to deduce a tag type from "FF FE". Maybe its a known one that I could simply extract from the file?

EDIT: I'm aware of "How do I repair corrupted EXIF?" from the FAQ. I was hoping to find a more specific solution to my problem :-)

Thanks in advance,
Thomas

[StarGeek]

I believe that 0xFFF8 is the start of a jpeg comment.  When you run exiftool on the file, do you see something like
Comment                         : denfused from  'IMG_3771_EOS.JPG' 'IMG_3770_EOS.JPG' 'IMG_3772_EOS.JPG' LV range  11.7  12.4  11.0

If so, you can remove the comment with
exiftool -comment= /path/to/file/

[TheDoc]

Thanks for the tip! That has made me look into the data a bit longer.

The text appears to be IFD0, ImageDescription. After exiftool -all= -tagsfromfile @ -all:all -unsafe -icc_profile the data is still there, only at the correct position. So this seems to be a good way to fix without loosing any data. Now I only need to limit the rebuild to files with this tag, e.g. by -if "defined $ImageDescription"?