[Originally posted by canonuser on 2006-06-12 19:40:26-07]
After using exiftool to shift DateTimeOriginal, the image is chopped off at bottom of picture. This only affects my photos where I used a Canon powershot S410 Digital Elph. I didn't have a problem with the image after using the tool to shift DateTimeOriginal on pictures taken with Kodak Easyshare V610 or the Nikon Coolpix 4200.
[Originally posted by exiftool on 2006-06-12 20:06:32-07]
Thanks for this bug report, this is very serious if true. However, I can't reproduce this problem with my sample S410 image. I used "exiftool -alldates+=3" to shift the date/times in my PowerShot S410 sample image, and after doing this, the image displayed fine.
Is your problem repeatable? Does it happen for more than one image? If so, I can figure out what is happening if you send me sample before and after images (either email them to philharvey66 at gmail.com or post a URL here). Also, what is the specific command-line you are using?
If the problem is not repeatable, I would run some disk utilities to be sure your hard disk isn't corrupting the files.
[Originally posted by canonuser on 2006-06-12 20:32:21-07]
Thanks for your quick response! I should have also mentioned in my post that an error was generated. The error stated: "Possibly incorrect maker notes offsets (fix by -275?)". The command that I ran that generated the error is "./exiftool -DateTimeOriginal-=12". The error happens everytime I run the command on pictures from the canon; but not on pictures from the Kodak or Nikon. I will send you before and after pictures.
[Originally posted by exiftool on 2006-06-13 00:37:30-07]
Thanks for the samples. Here is a summary of what I found:
1) Your "after" image was NOT written by ExifTool -- the IFD structure is not the way that ExifTool writes an image.
2) If I take your "before" image and edit it with "exiftool -datetimeoriginal-=12", the resulting image is fine (and the IFD structure is substantially different than the "after" image you sent).
3) The maker notes of your "before" image were corrupted by some other software. This is the reason for the warning that exiftool was giving. But this problem only affects the maker notes information, and could NOT result in exiftool corrupting the image.
4) There are other differences between your "before" and "after" images (CreateDate, ModifyDate, TimeCreated and DateCreated were shifted by +12 hours, and "Test" was written to ImageDescription, Headine and Caption-Abstract). So there were definitely some other steps between the two images that you were forgetting about.
My conclusion is that the image was not corrupted by exiftool, but by some other software. So I'm afraid that I need you to do a bit more investigating on your end if we are going to figure out what happened here.
[Originally posted by exiftool on 2006-06-19 12:37:49-07]
A quick update on the state of this thread:
More tests where performed by myself and 'canonuser', and we were both unable to reproduce this problem. So it still appears as if the problem was caused by some other software or possibly a bad hard disk, and not by ExifTool.