直播的学习与使用-----采集
// 捕获音视频
- (void)setupCaputureVideo
{
// 1.创建捕获会话,必须要强引用，否则会被释放
AVCaptureSession *captureSession = [[AVCaptureSession alloc] init];
_captureSession = captureSession;
// 2.获取摄像头设备，默认是后置摄像头
AVCaptureDevice *videoDevice = [self getVideoDevice:AVCaptureDevicePositionFront];
// 3.获取声音设备
AVCaptureDevice *audioDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio];
// 4.创建对应视频设备输入对象
AVCaptureDeviceInput *videoDeviceInput = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:nil];
_currentVideoDeviceInput = videoDeviceInput;
// 5.创建对应音频设备输入对象
AVCaptureDeviceInput *audioDeviceInput = [AVCaptureDeviceInput deviceInputWithDevice:audioDevice error:nil];
// 6.添加到会话中
// 注意“最好要判断是否能添加输入，会话不能添加空的
// 6.1 添加视频
if ([captureSession canAddInput:videoDeviceInput]) {
[captureSession addInput:videoDeviceInput];
}
// 6.2 添加音频
if ([captureSession canAddInput:audioDeviceInput]) {
[captureSession addInput:audioDeviceInput];
}
// 7.获取视频数据输出设备
AVCaptureVideoDataOutput *videoOutput = [[AVCaptureVideoDataOutput alloc] init];
// 7.1 设置代理，捕获视频样品数据
// 注意：队列必须是串行队列，才能获取到数据，而且不能为空
dispatch_queue_t videoQueue = dispatch_queue_create("Video Capture Queue", DISPATCH_QUEUE_SERIAL);
[videoOutput setSampleBufferDelegate:self queue:videoQueue];
if ([captureSession canAddOutput:videoOutput]) {
[captureSession addOutput:videoOutput];
}
// 8.获取音频数据输出设备
AVCaptureAudioDataOutput *audioOutput = [[AVCaptureAudioDataOutput alloc] init];
// 8.2 设置代理，捕获视频样品数据
// 注意：队列必须是串行队列，才能获取到数据，而且不能为空
dispatch_queue_t audioQueue = dispatch_queue_create("Audio Capture Queue", DISPATCH_QUEUE_SERIAL);
[audioOutput setSampleBufferDelegate:self queue:audioQueue];
if ([captureSession canAddOutput:audioOutput]) {
[captureSession addOutput:audioOutput];
}
// 9.获取视频输入与输出连接，用于分辨音视频数据
_videoConnection = [videoOutput connectionWithMediaType:AVMediaTypeVideo];
// 10.添加视频预览图层
AVCaptureVideoPreviewLayer *previedLayer = [AVCaptureVideoPreviewLayer layerWithSession:captureSession];
previedLayer.frame = [UIScreen mainScreen].bounds;
[self.view.layer insertSublayer:previedLayer atIndex:0];
_previedLayer = previedLayer;
// 11.启动会话
[captureSession startRunning];
}
// 指定摄像头方向获取摄像头
- (AVCaptureDevice *)getVideoDevice:(AVCaptureDevicePosition)position
{
NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
for (AVCaptureDevice *device in devices) {
if (device.position == position) {
return device;
}
}
return nil;
}
#pragma mark - AVCaptureVideoDataOutputSampleBufferDelegate
// 获取输入设备数据，有可能是音频有可能是视频
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection
{
if (_videoConnection == connection) {
NSLog(@"采集到视频数据");
} else {
NSLog(@"采集到音频数据");
}
}
