iPhone Duo: Does CameraCaptureAccessory accept touch, what counts as an active camera session, and can both front cameras run at once?

Question

Created 18h

Replies 4

Boosts 0

Participants 2

After watching "Leverage multiple displays and scenes on iPhone Duo" and "Build a great camera experience for iPhone Duo", we have four questions about the outer display while the device is open:

Does a view hosted in CameraCaptureAccessory receive touch input on the outer display, or is it display-only?
The accessory is described as available when the app "has an active camera session." Does that require a running preview layer or an attached output (photo, movie or data), or is a running AVCaptureSession with an input enough? Is a session whose main purpose is to host the accessory a supported use?
Can AVCaptureMultiCamSession run the inner (under-display) front camera and the outer front camera at the same time on iPhone Duo? If so, which device-type combinations are supported, and are there thermal or power limits?
Is CameraCaptureAccessory the only way for an app to show content on the outer display while the inner display is live, or are scene accessories that don't depend on the camera planned?

Our use case is not photography. We're exploring a companion view for a second person sitting across from the device owner, so we want to understand whether the camera accessory is the right tool before designing around it.

Answer 1

Media Engineer OP

Apple

15h

For question #1: yes, the CameraCaptureAccessory view can receive touches. It's recommended to use very few or no UI buttons or controls on that scene though since there’s nothing preventing accidental touches.

Answer 2

Media Engineer OP

Apple

15h

For #2, CameraCaptureAccessory is what it says it is. It's for camera capture use cases. Creating an AVCaptureSession and adding an input only is not supported, since that doesn't actually run the camera. You must show a camera preview on one or both of the displays.

Answer 3

Media Engineer OP

Apple

15h

For #3, yes, inner and outer built in ultra wide cameras can be used simultaneously using Multicam session. AVCaptureDevice.DiscoverySession 's supportedMultiCamDeviceSets will tell you all the allowed combinations of devices you can use. The max number of cameras that can run simultaneously is 3.

Answer 4

Media Engineer OP

Apple

15h

For #4, yes, CameraCaptureAccessory is the only way to use both inner and outer displays at the same time. Camera cases are the only supported and intended use cases for dual display at present.