Open Radar

 
Area:
AVFoundation

Summary:

If you configure AVFoundation to detect faces on an iPhone 8 Plus and also hold the device in portrait mode, AVFoundation does not report the face yawAngle correctly.


Steps to Reproduce:

Get an iPhone 8 Plus, hold it upright in portrait mode, and run the enclosed sample project.

This project contains my minimal modifications to Apple sample code for the AVFoundation face detector. 

One modification is just to add an overlay layer that displayed the detected face yawAngle onscreen. The other, critical modification is to configure AVFoundation to detect *only faces*, rather than all possible metadata types. This last change triggers the bug.

While still holding the device in portrait mode, turn your head to left and right.

Expected Results:

I expect to see the  yawAngle displayed —

- as it is on any device besides an iPhone 8 Plus (or iPhone 8)
- as it is if I physically re-orient the iPhone 8 Plus so it's screen faces the sky, and then bring it back to portrait orientation.
- as it is if I, while holding the device in portrait mode, roll my head 90 degrees counterclockwise around the axis going from my nose to the phone, and _then_ turn my head left or right.  (In other words, the faceYaw variable is behaving as if it thinks the device is in landscape orientation, and this weird motion lines my head up with that expectation)

Actual Results:

I do not see yawAngle updated at all.

Version/Build:

11.0.3 (15A432)