iphone视频聊天代码实现

转自：http://blog.csdn.net/zxc110110/article/details/7191016

视频聊天从摄像头中取得缓冲数据，转换成NSData，通过网络发送，接收端取得NSData后把NSData转换成图像，双方不停的收发数据，播放图像，就形成了视频聊天。废话不多说，直接上代码：

首先创建视频输入输出：

NSError *error= nil;
    
    //Setup the video input
    AVCaptureDevice *videoDevice=[self getFrontCamera];//[AVCaptureDevicedefaultDeviceWithMediaType: AVMediaTypeVideo];
    //Create a device input with the device and add it to thesession.
    AVCaptureDeviceInput *videoInput=[AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:&error];
    //Setup the video output
    _videoOutput =[[AVCaptureVideoDataOutput alloc] init];
    _videoOutput.alwaysDiscardsLateVideoFrames = NO;
    _videoOutput.videoSettings =
    [NSDictionary dictionaryWithObject:
    [NSNumber numberWithInt:kCVPixelFormatType_32BGRA] forKey:(id)kCVPixelBufferPixelFormatTypeKey];     
    
    
    //Create the session
    _capSession =[[AVCaptureSession alloc] init];
    [_capSession addInput:videoInput];
    //[_capSessionaddInput:audioInput];
    [_capSession addOutput:_videoOutput];
    //[_capSessionaddOutput:_audioOutput];
    
    _capSession.sessionPreset = AVCaptureSessionPresetLow;     
    
    //Setup the queue
    dispatch_queue_t queue= dispatch_queue_create("MyQueue", NULL);
    [_videoOutput setSampleBufferDelegate:self queue:queue];
    [_audioOutput setSampleBufferDelegate:self queue:queue];
    dispatch_release(queue);
    [_capSession startRunning];

通过AVCaptureVideoDataOutputSampleBufferDelegate代理 取得摄像头数据

#pragma mark AVCaptureSession delegate
-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
      fromConnection:(AVCaptureConnection *)connection
{
    
    NSData *data=[NSData dataWithBytes:&sampleBuffer length:malloc_size(sampleBuffer)];
    [self recieveVideoFromData:data];
}

收到数据后转换成图像

-(void)recieveVideoFromData:(NSData *)data{
    CMSampleBufferRef sampleBuffer;
    [data getBytes:&sampleBuffer length:sizeof(sampleBuffer)];
    NSAutoreleasePool *pool =[[NSAutoreleasePool alloc] init];
    
    CVImageBufferRef imageBuffer= CMSampleBufferGetImageBuffer(sampleBuffer);
    CVPixelBufferLockBaseAddress(imageBuffer,0);
    uint8_t *baseAddress=(uint8_t *)CVPixelBufferGetBaseAddress(imageBuffer);
    size_t bytesPerRow= CVPixelBufferGetBytesPerRow(imageBuffer);
    size_t width= CVPixelBufferGetWidth(imageBuffer);
    size_t height= CVPixelBufferGetHeight(imageBuffer);
    
    CGColorSpaceRef colorSpace= CGColorSpaceCreateDeviceRGB();
    CGContextRef newContext= CGBitmapContextCreate(baseAddress,
                                                    width,height, 8, bytesPerRow,colorSpace,
                                                    kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);
    CGImageRef newImage= CGBitmapContextCreateImage(newContext);
    
    CGContextRelease(newContext);
    CGColorSpaceRelease(colorSpace);
    
    UIImage *image=[UIImage imageWithCGImage:newImage scale:1.0
                                  orientation:UIImageOrientationRight];
    
    CGImageRelease(newImage);
    [self.imageView performSelectorOnMainThread:@selector(setImage:)
                                withObject:image waitUntilDone:YES];
    CVPixelBufferUnlockBaseAddress(imageBuffer,0);
    
    [pool drain];
    
}