Canon 20D -- ThumbnailImage runs outside EXIF data (warning)

[Archive]

[Originally posted by darinh on 2008-02-24 17:01:21-08]

I needed to change the Date and Time information in some JPG images that I recently took since my 20D decided in the middle of a photo shoot that it wasn't really 2008, it was 01/01/2000.  Anyway, I found the exiftool executable for Windows.  I actually plan to use the Perl module long term, but I wanted to make a quick and dirty change for about 100 files so they would be correct in my photo library.

So, the tool did its job, but it gave me a warning, one for every file that it processed.  Below is the command and the output.

Code:

C:\Pics> exiftool "-DateTimeOriginal+=8:1:20 15:08:0" test -AllDates=1
Warning: [minor] ThumbnailImage runs outside EXIF data by 8 bytes (truncated) - test/_MG_5716.JPG
Warning: [minor] ThumbnailImage runs outside EXIF data by 8 bytes (truncated) - test/_MG_5717.JPG
    1 directories scanned
    2 image files updated

I have firmware 2.0.3 on my 20D.

Although the DateTime update seems to have worked correctly, I am wondering if there is something wrong with my camera, or something else.  I would really feel better about using the exiftool if it did not give me these warnings.

Any help would be greatly appreciated.

-darinh

[Archive]

[Originally posted by exiftool on 2008-02-24 19:02:20-08]

Hi Darinh,

ExifTool will issue a warning if it detects a problem in the
file format.  But there is no need to feel bad.  These types of
problems are more common than you might think, especially
in the proprietary maker notes (I have mentioned a few of them
https://exiftool.org/idiosyncracies.html" target="_blank">here
if you are interested).  Apparently the manufacturers
don't have any development tools that are as comprehensive
as exiftool.

I am familiar with this particular problem, and in this case,
the recorded size of the thumbnail image is too large, so
"truncating" the thumbnail image to the size of the valid
data is the right thing to do.  So using -m in this
case to ignore the warning should be safe, if that makes
you feel any better. https://exiftool.org/forum/Smileys/default/wink.gif" alt="Wink" border="0" />

- Phil

[Archive]

[Originally posted by darinh on 2008-02-25 01:58:29-08]

Hi Phil!

Thanks for the quick response.  I had a feeling that was the case, but I haven't used any utilities to change the EXIF data before, so I didn't expect this problem.  I found the -m, but I don't like to mask issues, so I will let it ride.

Hopefully my camera will not make a habit out of changing the date on me, and then I really won't have to worry.

BTW, I really like exiftool!  SO MANY FEATURES!!!

I am sure that it will be useful for lots of chores!

Thanks again!

-darin