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https://wiki.multimedia.cx/index.php/FFmpeg_Metadata
XMP data can be read by ffprobe, e.g.: ffprobe -v quiet -print_format json -show_format -export_xmp 1 -show_streams "[0000-0119].mov"
Also, exiftool appears to have support for reading and writing xmp data: https://exiftool.org/forum/index.php?topic=8745.0 certainly:
Annotations and Notes
The other area that common specifications could be defined is how annotations and notes could be sent back to the vendor, in a format that is ready for ingest into the tracking system.
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