None standard sized videos not playing in AVPlayer

I have a requirement to play square videos in my app. The video overlaps and is anchored to an image seen in the devices display. I.e. I am displaying the results of the camera in realtime and overlaying my video on a portion of the screen.

This works well but when I then request within the app to play the video in full screen, the video just shows blank and will not load into the AVPlayer full screen.

The video is in H.264 format.

I welcome any thoughts or suggestions as this has me stumped. Is it possible that videos only play in full screen for certain video sizes as seems to be suggested in the documentation?

A supplementary question if square ( or other shaped videos ) can not be played full screen. Is it possible to have a transparent background to part of the video so when overlaid the camera feed it looks square but is of a supported size so that it also plays full screen in the AVPlayer.

Thank you for reading.

Graeme

None standard sized videos not playing in AVPlayer
 
 
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