IOS7-简单的调用本地摄像头采集视频

1.视图类实现 <pre name="code" class="objc">AVCaptureVideoDataOutputSampleBufferDelegate  接口

@interface MainViewController ()<AVCaptureVideoDataOutputSampleBufferDelegate>
@property (strong,nonatomic)AVCaptureVideoPreviewLayer * preview;
@end

- (void)startCapture
{
//device
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

//input
AVCaptureDeviceInput *input = [[AVCaptureDeviceInput alloc]initWithDevice:device error:nil];

//output
AVCaptureVideoDataOutput *outputData = [AVCaptureVideoDataOutput new];
[outputData setSampleBufferDelegate:self queue:dispatch_get_main_queue()];

//session
AVCaptureSession *session = [AVCaptureSession new];
if ([session canAddInput:input]) {
[session addInput:input];
}
if ([session canAddOutput:outputData]) {
[session addOutput:outputData];
}

_preview = [[AVCaptureVideoPreviewLayer alloc]initWithSession:session];
_preview.videoGravity = AVLayerVideoGravityResizeAspectFill;
_preview.frame =CGRectMake(20,110,280,280);
[self.view.layer insertSublayer:self.preview atIndex:0];

[session startRunning];
}