如何在iOS 8和Yosemite之间设置镜像会话？

Question

On OS X Yosemite, the screen of an iOS 8 device can be mirrored to the OS X machine and saved as a media file. This can be done manually using QuickTime Player, but I want to do the same programatically.

Reading the docs, the iOS 8 device should be exposed as a webcam.

Calling [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo] on my Mac returns an NSArray with no elements.

How can I setup a mirroring session using iOS 8 and Yosemite? How can I detect the capture device for the mirroring session?

Answer 1

Quoting from p28 of the PDF transcript for WWDC 2014 session #508 “Camera Capture: Manual Controls” :

iOS devices are presented as CoreMedia IO “DAL” plug-ins

You must opt in to see iOS screen devices in your OS X app

 CMIOObjectPropertyAddress prop = { kCMIOHardwarePropertyAllowScreenCaptureDevices, kCMIOObjectPropertyScopeGlobal, kCMIOObjectPropertyElementMaster }; UInt32 allow = 1; CMIOObjectSetPropertyData( kCMIOObjectSystemObject, &prop, 0, NULL, sizeof(allow), &allow ); 

Also, see my blog for CoreMediaIO capture sample to directly intercept the raw compressed payload sent out from the device