For episodes of TV shows using MP4 tags, it would be particularly useful to be able to select a time code (either absolute, e. g. at 30s, or relative, e. g. 10% of runtime) from which the frame would be used as a thumbnail picture since cover images are usually not available.
Kodi uses video tags and hence embedded graphics since the latest major release, v18 Leia.
Quicktime MOV apparently supports tags to specify the time code for preview images (poster) and clips, i. e. there is no need to actually embed an image that is already available as a frame. This info is stored in
moov. Iʼm not sure whether that is possible in MP4 as well, or supported by players and media centers.
- Preview time
The time value in the movie at which the preview begins.
- Preview duration
The duration of the movie preview in movie time scale units.
- Poster time
The time value of the time of the movie poster.