ExifTool Forum

ExifTool => Bug Reports / Feature Requests => Topic started by: tipa on January 28, 2025, 06:28:24 PM

Title: [Bug] Writing GPSPosition to .mov video corrupts file
Post by: tipa on January 28, 2025, 06:28:24 PM
When trying to write location information to a certain .mov video, it corrupts the file and it is no longer playable on either Windows or macOS.
Below the required information as requested here (https://exiftool.org/forum/index.php?topic=6.0)

1) System type (Windows XP, Linux, Mac, etc)
Windows 11 26100.2894 & macOS 15.3
Powershell on Windows

2) The ExifTool version you are using (the output of the "exiftool -ver" command).
13.16

3) The specific command line you are using (or a sample script if having problems with the API).
.\exiftool.exe -GPSPosition="0.0, 0.0" .\example.mov
4) The console output from the command.
1 image files updated
5) It is often useful to attach a sample image which exhibits the problem
Example video file (https://1drv.ms/v/s!Ao11bhuirfKf0dkug3j4YyeMlRcnig?e=U3ShtH)
Title: Re: [Bug] Writing GPSPosition to .mov video corrupts file
Post by: StarGeek on January 28, 2025, 07:29:25 PM
Strange. Exiftool reports this
C:\>exiftool -g1 -a -s -warning -validate  Y:\!temp\x\y\example.mov
---- ExifTool ----
Warning                         : Duplicate tag 'wide' at MOV
Validate                        : 1 Warning

But this ffmpeg command which is supposed to check for problem files reports nothing
C:\> ffmpeg.exe -v error -i  Y:\!temp\x\y\example.mov -f null -

C:\>
Title: Re: [Bug] Writing GPSPosition to .mov video corrupts file
Post by: Phil Harvey on January 29, 2025, 08:10:22 AM
The problem is that the first 'wide' atom in this movie has an invalid size.  According to the QuickTime specification:

QuoteThe 'wide' atom is exactly 8 bytes in size, and consists solely of its size and type fields. It contains no other data.

but the 'wide' atom in this movie is 12 bytes, and ExifTool isn't handling this properly.  I'll patch ExifTool 13.17 to check the size of 'wide' atoms when writing, and handle invalid sizes by issuing a warning and skipping the extra bytes.

Thanks for this report.

- Phil
Title: Re: [Bug] Writing GPSPosition to .mov video corrupts file
Post by: tipa on January 29, 2025, 09:23:16 AM
Thank you so much for the quick response - happy to hear that it's getting fixed in the next update!
Title: Re: [Bug] Writing GPSPosition to .mov video corrupts file
Post by: Phil Harvey on January 29, 2025, 09:45:10 AM
Version 13.17 is now available.

- Phil