Hello.

I'm not very familiar with perl, or exif, but recently I've had some problems modifying the exif data contained in jpegs which were written by various Apple products, including Aperture ( more accurately the programs which I use, which were written by other people, which use this library have been having these problems).

At some point in time, Apple changed things so that Aperture now produces jpegs like:
http://www.ugcs.caltech.edu/~davinm/exiftool/bad.jpg
Opening it and saving as a jpeg in photoshop cs2 produces:
http://www.ugcs.caltech.edu/~davinm/exiftool/good.jpg

and

both produce output which is understandably slightly different from each other. But,

works (1 image files updated) and

fails (Error: Bad format (0) for IFD0 entry 7 - bad.jpg 0 image files updated 1 files weren't updated due to errors)

Why?
Is this because the exif bytes (45 78 69 66 ) are closer to the beginning of the file in good.jpg, and are further away in bad.jpg ?
Is this a bug in exiftool ? If so, can it be fixed ?
Is this Apple's fault (i.e. are they not following the exif spec) ? If so, what do I tell them the problem is ?


Thanks.