iPhone 7 Plus – AVFoundation双摄像头

目前我正在积极研究这个问题，但是现在iPhone 7 Plus具有双摄像头系统，AVFoundation能够让您同时处理每个特定摄像头的video帧吗？

我想/我希望能够处理来自两个AVCaptureDevice实例的输出，同时给定一个位置。

Answer 1

在更新的AVFoundation文档（ AVCaptureDeviceType ）中有新的设备types： builtInWideAngleCamera和builtInTelephotoCamera 。 因此，应该可以创build多个捕获会话，并同时从两个捕获会话获得反馈。

Answer 2

您只能将一个摄像机添加到AVCaptureSession中。 例如，您可以在正面和背面相机之间切换，但不能同时使用两者。 7 Plus的两个后置摄像头也是一样，你必须select。 但是，有一个小的区别，因为你也可以调用一个“双相机”，当你缩放时合并来自两个相机的图像。 但是，这只适用于静态照片，你只会得到一个图像/捕获缓冲区。 对于video，你必须select相机。

要select相机，您可以使用新的AVCaptureDeviceDiscoverySession。 要使用双相机：

 @property (nonatomic) AVCaptureDevice *backCamera; @property (nonatomic) AVCaptureDeviceInput *backCameraInput; if([AVCaptureDeviceDiscoverySession class]){ NSArray *allTypes = @[AVCaptureDeviceTypeBuiltInDuoCamera, AVCaptureDeviceTypeBuiltInWideAngleCamera, AVCaptureDeviceTypeBuiltInTelephotoCamera ]; AVCaptureDeviceDiscoverySession *discoverySession = [AVCaptureDeviceDiscoverySession discoverySessionWithDeviceTypes:allTypes mediaType:AVMediaTypeVideo position:AVCaptureDevicePositionBack]; for(AVCaptureDevice *device in discoverySession.devices) { if(device.deviceType== AVCaptureDeviceTypeBuiltInDuoCamera){ self.backCamera = device; self.backCameraInput = [AVCaptureDeviceInput deviceInputWithDevice:self.backCamera error:&error]; } } } if(!self.backCamera){ self.backCamera = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo]; self.backCameraInput = [AVCaptureDeviceInput deviceInputWithDevice:self.backCamera error:&error]; } 

单独使用广angular和远摄相机

 @property (nonatomic) AVCaptureDevice *backCamera; @property (nonatomic) AVCaptureDeviceInput *backCameraInput; @property (nonatomic) AVCaptureDevice *teleCamera; @property (nonatomic) AVCaptureDeviceInput *teleCameraInput; if([AVCaptureDeviceDiscoverySession class]){ NSArray *allTypes = @[AVCaptureDeviceTypeBuiltInDuoCamera, AVCaptureDeviceTypeBuiltInWideAngleCamera, AVCaptureDeviceTypeBuiltInTelephotoCamera ]; AVCaptureDeviceDiscoverySession *discoverySession = [AVCaptureDeviceDiscoverySession discoverySessionWithDeviceTypes:allTypes mediaType:AVMediaTypeVideo position:AVCaptureDevicePositionBack]; for(AVCaptureDevice *device in discoverySession.devices) { if(device.deviceType==AVCaptureDeviceTypeBuiltInWideAngleCamera){ self.backCamera = device; self.backCameraInput = [AVCaptureDeviceInput deviceInputWithDevice:self.backCamera error:&error]; } if(device.deviceType==AVCaptureDeviceTypeBuiltInTelephotoCamera){ self.teleCamera = device; self.teleCameraInput = [AVCaptureDeviceInput deviceInputWithDevice:self.teleCamera error:&error]; } } } if(!self.backCamera){ self.backCamera = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo]; self.backCameraInput = [AVCaptureDeviceInput deviceInputWithDevice:self.backCamera error:&error]; } 

如果不这样做，或者保留旧代码，即使放大，也只能使用广angular相机。

编辑：在iOS 11中有新的AVCapturePhotoSettings称为dualCameraDualPhotoDeliveryEnabled。 它可以让你同时拍摄两张静止图像，但是，没有stream媒体/video。