SPRM 7: Current Part of Title Number
The Part of Title is the current chapter number of the track being played.
This SPRM is useful if you need to know the last or current chapter played for that track.
There may be reasons to jump to the beginning of the last chapter played from any menu,
not just resume to the last place in the video. An example of this would be a training film
that requires the viewer to resume watching the chapter from the beginning if they do
not watch the chapter in its entirety.