在iOS的双摄像头输出

Question

我想用做双屏幕内置摄像头在iOS上

我想下面的代码，但它表明只有一个视图。

这是一个自然的结果，我知道了。

下面是我用什么代码..

- (void)prepareCameraView:(UIView *)window
{
    AVCaptureSession *session = [[AVCaptureSession alloc] init];
    session.sessionPreset = AVCaptureSessionPresetMedium;

    CALayer *viewLayer = window.layer;
    NSLog(@"viewLayer = %@", viewLayer);

    AVCaptureVideoPreviewLayer *captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] 
                                                            initWithSession:session];
    captureVideoPreviewLayer.frame = window.bounds;
    [window.layer addSublayer:captureVideoPreviewLayer];    
    AVCaptureDevice *captureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

    NSError *error = nil;
    AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:&error];
    if (!input) 
    {
        NSLog(@"ERROR : trying to open camera : %@", error);
    }

    [session addInput:input];

    [session startRunning];
}

我怎样才能在iOS上获得双屏幕？

Answer 1

 // Use this code





  AVCaptureSession *session = [AVCaptureSession new];
  AVCaptureDevice *inputDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
NSError *error;
AVCaptureDeviceInput *deviceInput = [AVCaptureDeviceInput deviceInputWithDevice:inputDevice error:&error];

if ( [session canAddInput:deviceInput])
{
    [session addInput:deviceInput];
}
AVCaptureVideoPreviewLayer *previewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];
[previewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
[previewLayer setFrame:CGRectMake(0.0, 0.0, self.view.bounds.size.width, self.view.bounds.size.height)];

NSUInteger replicatorInstances = 2;
CGFloat replicatorViewHeight = (self.view.bounds.size.height - 64)/replicatorInstances;
CAReplicatorLayer *replicatorLayer = [CAReplicatorLayer layer];
replicatorLayer.frame = CGRectMake(0, 0.0, self.view.bounds.size.width, replicatorViewHeight);
replicatorLayer.instanceCount = replicatorInstances;
replicatorLayer.instanceTransform = CATransform3DMakeTranslation(0.0, replicatorViewHeight, 0.0);

[replicatorLayer addSublayer:previewLayer];
[self.view.layer addSublayer:replicatorLayer];
[session startRunning];

Answer 2

尝试这个：

- (void)prepareCameraView:(UIView *)window
{
    NSArray *captureDevices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];

    {
        AVCaptureSession *session = [[AVCaptureSession alloc] init];
        session.sessionPreset = AVCaptureSessionPresetMedium;

        CALayer *viewLayer = window.layer;
        NSLog(@"viewLayer = %@", viewLayer);

        AVCaptureVideoPreviewLayer *captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];
        captureVideoPreviewLayer.frame = CGRectMake(0.0f, 0.0f, window.bounds.size.width/2.0f, window.bounds.size.height);
        [window.layer addSublayer:captureVideoPreviewLayer];

        NSError *error = nil;
        AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:[captureDevices objectAtIndex:0] error:&error];
        if (!input) 
        {
            NSLog(@"ERROR : trying to open camera : %@", error);
        }

        [session addInput:input];

        [session startRunning];
    }

    {
        AVCaptureSession *session = [[AVCaptureSession alloc] init];
        session.sessionPreset = AVCaptureSessionPresetMedium;

        CALayer *viewLayer = window.layer;
        NSLog(@"viewLayer = %@", viewLayer);

        AVCaptureVideoPreviewLayer *captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];
        captureVideoPreviewLayer.frame = CGRectMake(window.bounds.size.width/2.0f, 0.0f, window.bounds.size.width/2.0f, window.bounds.size.height);
        [window.layer addSublayer:captureVideoPreviewLayer];

        NSError *error = nil;
        AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:[captureDevices objectAtIndex:1] error:&error];
        if (!input) 
        {
            NSLog(@"ERROR : trying to open camera : %@", error);
        }

        [session addInput:input];

        [session startRunning];
    }

}

需要注意的是它使绝对没有检查实际上有2个摄像头并将其拆分其垂直所以这在景观可能是最好的观察。你会想一些检查添加到该代码，你想怎么使用它之前，制定出每个摄像头的层正好锻炼。