Open Radar

 
Summary:
When using AVPlayer to play a HLS master playlist containing a low-bitrate audio-only representation of the content, if the player adapts down to the audio only stream, it reports an incorrect presentation size.

On my testing on an iPad Air, the player always reported a presentation size of {1280, 720} when playing the audio-only stream.

All other presentation size changes seemed to be reported correctly. For example, when I added KVO on presentationSize during a playback session which adapted from 240p => 144p => audio only, I observed the following:

presentationSize changed: NSSize: {426, 240}
presentationSize changed: NSSize: {256, 144}
presentationSize changed: NSSize: {1280, 720} 

(the last line being logged when the player began to play the audio-only stream).

Steps to Reproduce:
Play a HLS master playlist containing an audio-only stream.
Throttle network bandwidth using a proxy such as Charles
Observe changes to AVPlayerItem presentationSize
Wait for the player to adapt to the audio-only stream.
Note that the presentation size is incorrectly reported.

Expected Results:
The presentation size should be reported as {0, 0} when playing an audio-only stream.