I am working an application that uses camera X in real time to display supplemental information on top of the preview. We are getting speed data from an external bluetooth radar device.
During video capture I save that supplemental data to the meta data track.
For in app view playback we access that meta data track and re-render the supplemental data on top of the video.
We also would like to export this video to share as a fully render mp4, and product wants multiple formats of overlays on top of the video. For example maybe the data is in the top right for facebook, but the bottom left for instagram. (Dumb example, but you get the idea)
In app video playback is not a problem and quick because we aren't re-rendering frame by frame, but exportation is taking a very long time.
Any suggestions on how we would implement this?
We've considered in real time creating multiple videos with the overlay in the right position, but ideally we would generate the correct video post capture so as to not eat up the user's storage.