[kwlug-disc] Image Comparison

[Chris Frey]

On Tue, Aug 11, 2009 at 10:12:04PM -0400, L.D. Paniak wrote:
> Is the EXIF data compressed with the image or just a header floating on
> top? Could one just compare the tails of the files?
> 
> for file in *; do echo "$(tail $file |md5sum) $file" >>tmp;  done
> 
> sort tmp

According to a quick scan of wikipedia, looks like the EXIF header is
at the beginning of the file.  Looking at some sample files from my
camera, the information is not compressed.

So looks like tail would work too, as long as the end doesn't contain
the same data across multiple pictures.  I don't know if things like
colour profiles are stored at the end or not.

- Chris