ExifTool Forum

ExifTool => The "exiftool" Application => Topic started by: gheppell on April 13, 2020, 04:09:46 PM

Title: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: gheppell on April 13, 2020, 04:09:46 PM
Hello. 

I am able to add GPS exif data to an mp4 file with a third party application.  However, Google does not read this information when I upload to Photos.  Subsequently, I learned that to the extent that I add the gps information  to the quicktime gps cooridnates field/tag, it will work in Google Photos.  To shorten the process for a number of my files, I would like to have the exif:gpsposition field copied to the quicktime:gpscoordinates field.

I have tried
exiftool "-quicktime:gpscoordinates<exif:gpsposition" and many variants thereof,  but to no avail. I continually get the following in the command line:   "Warning: No writable tags set from {my filename}"

I took this to mean that the quicktime:gpscoordinates tag wasn't writable via exiftool but I tested it with specific coordinates (ie. -quicktime:coordinates=51.12345, 114.43454) and it worked well.

Any thoughts?   Thank you.
Title: Re: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: Alan Clifford on April 13, 2020, 04:31:33 PM
Do mp4 files have exif?  Maybe xmp

Check your file with

exiftool -G -a filename_goes_here
Title: Re: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: StarGeek on April 13, 2020, 04:43:49 PM
The problem is there is no such thing as an EXIF:GPSPosition tag.  If you add the -G (groupNames) option (https://exiftool.org/exiftool_pod.html#G-NUM-:NUM...--groupNames), you'll see that GPSPosition is a Composite tag (https://exiftool.org/TagNames/Composite.html).  It's derived from other tags in the file.  Additionally, I'm guessing that the GPS coordinates that the other program is adding are in the XMP group (an Adobe program?). 

Try this
exiftool "-GPSCoordinates<GPSPosition" /path/to/files

In my opinion, you shouldn't add group names unless you know you need the data in a specific group.  Exiftool usually puts the data in the best spot on its own.
Title: Re: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: gheppell on April 13, 2020, 05:10:28 PM
No luck.  I had tried that variant but did try it again.  Still, I get the '..no writable tags set" warning.  Hmmm?
Title: Re: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: StarGeek on April 13, 2020, 05:12:26 PM
What is the output of
exiftool -g1 -a -s -gps* file.mp4
Title: Re: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: gheppell on April 13, 2020, 05:16:56 PM
???  Nothing.  No warnings or errors.  Just no output.
Title: Re: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: StarGeek on April 13, 2020, 05:18:44 PM
There's your answer.  The other program you're using isn't adding any GPS coordinates to the file.

Is it possible it is using an XMP sidecar file?  Otherwise, it's probably keeping the data in its own database.
Title: Re: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: gheppell on April 13, 2020, 05:19:05 PM
Here is the cut/paste from the command line.

C:\Users\Gord.000\Desktop\New folder>exiftool -g1 -a -s -gps*  test.mp4

C:\Users\Gord.000\Desktop\New folder>pause
Press any key to continue . . .
Title: Re: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: gheppell on April 13, 2020, 05:22:08 PM
could be as you suggest.  I have been deleting the xmp file with each gps change to ensure that the exif data is still there, but it must just be in the application's db as oppsed to actually written to the file.  It works fine once I cut/paste the components into the GPS Coordinates field of the software (IMatch) but this just takes extra time.  Looks like I am stuck with it...

thanks.
Title: Re: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: StarGeek on April 13, 2020, 05:47:44 PM
I believe that Imatch will use XMP sidecar files by default for MP4 files.  My copy is a couple years old so I don't know if Mario has updated it to write Quicktime data or not.  But if you remove the sidecars when the data hasn't been written to the file, I don't think that the data will survive exiting and restarting the program, though I could be wrong.

To get IMatch to write the data into the file, goto Edit menu > Preferences > Metadata 2 tab.  Click "Configure File Formats",  scroll down the file extensions to find MP4, unclick use default settings, and set the "XMP Sidecar Files" to "Embed XMP in file"
Title: Re: Writing quicktime GPS coordinates from exif GPS information in video files
Post by: gheppell on April 13, 2020, 06:01:32 PM
You mademe or sir, are a scholar and a gentlewoman/man.  Worked like a charm.  Now, once the GPSPosition is written via IMatch using the map panel and a couple of clicks, exiftool "-GPSCoordinates<GPSPosition"  works as I had hoped. 

Thank you !!