PiP Bug Demo

I believe there is an Apple-level framework issue when using AVPictureInPictureController with an AVSampleBufferDisplayLayer content source on macOS or tvOS

This bug manifests itself with the following consequence: It is not possible to start a PiP session on tvOS or macOS when using an AVSampleBufferDisplayLayer as a content source for AVPictureInPictureController.

Tested on following platforms:

macOS: 12.0.1 (21A559)
iOS: 15.1 (19B74)
tvOS: 15.1.1 (19J587)

Submitted to Apple as FB9751461


PLEASE NOTE: THIS CODE MUST BE RUN ON REAL DEVICES. SIMULATORS DO NOT SUPPORT THIS NEW PIP API


This project presents 3 apps, one for iOS, tvOS, and macOS – which are all setup to use Picture in Picture with AVSampleBufferDisplayLayer as the content source. This is new API available in iOS 15, tvOS 15, and macOS 12.

For iOS and tvOS I have added the Picture in Picture background mode in Signing and Capabilities (Info.plist entry). There doesn’t seem to be an equivelent on macOS.

I have also set the AVAudioSession to .playback on iOS and tvOS which is required to support Picture in Picture. Again, there seems to be no equivelent on macOS but I could be wrong?

do {
    try AVAudioSession.sharedInstance().setCategory(.playback, mode: .moviePlayback)
} catch {
    print("Setting category to AVAudioSessionCategoryPlayback failed.")
}

In the relevant apps’ view controller code, the AVPictureInPictureController setup is as follows:

let contentSource = AVPictureInPictureController.ContentSource(sampleBufferDisplayLayer: videoProvider.bufferDisplayLayer, playbackDelegate: self)


pipController = AVPictureInPictureController(contentSource: contentSource)
pipController.delegate = self

On iOS, as soon as I instantiate AVPictureInPictureController(contentSource: contentSource) I am receiving delegate callbacks to the AVPictureInPictureSampleBufferPlaybackDelegate methods:

IOSViewController.pictureInPictureControllerTimeRangeForPlayback(_:)
IOSViewController.pictureInPictureControllerIsPlaybackPaused(_:)

which it seems necessary for the system to call in order to setup Picture in Picture playback.

However, these methods ARE NEVER CALLED on tvOS or macOS

As a result, pipController.isPictureInPicturePossible is true on iOS but is always false on tvOS and macOS.

I suspect that somewhere in the guts of the AVKit/AVFoundation framework, these delegate methods are not being queried on tvOS nor macOS and so PiP setup is never completed and it will always fail.

GitHub

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