Iphone 如何在Xcode中逐帧获取图片帧

嗨，我想用iphone后置摄像头一帧一帧地拍摄照片。我到目前为止所做的一切

我在全模式下打开相机

• （IBAction）showCameraUI{ [自启动MeracontrollerFromViewController:自启动 使用代理：self]； }

• （BOOL）startCameraControllerFromViewController:（UIViewController*）控制器 usingDelegate:（id）delegate{

}

设置AVCapture以逐帧获取图片

• （无效）设置捕获会话{ n错误*错误=nil

//session.AVCaptureTorchModeOn=YES

// Configure the session to produce lower resolution video frames, if your
// processing algorithm can cope. We'll specify medium quality for the
// chosen device.
session.sessionPreset = AVCaptureSessionPresetLow;

// Find a suitable AVCaptureDevice
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
[device lockForConfiguration:nil];
[device setTorchMode:AVCaptureTorchModeOn];  // use AVCaptureTorchModeOff to turn off
[device unlockForConfiguration];
// Create a device input with the device and add it to the session.
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device
                                                                    error:&error];
if (!input) {
    // Handling the error appropriately.
}
[session addInput:input];

// Create a VideoDataOutput and add it to the session
AVCaptureVideoDataOutput *output = [[AVCaptureVideoDataOutput alloc] init] ;

//output.alwaysDiscardsLateVideoFrames=是； [会话添加输出：输出]

dispatch_queue_t queue = dispatch_queue_create("MyQueue", NULL);
[output setSampleBufferDelegate:self queue:queue];
dispatch_release(queue);

// Specify the pixel format
output.videoSettings =
[NSDictionary dictionaryWithObject:
 [NSNumber numberWithInt:kCVPixelFormatType_32BGRA]
                            forKey:(id)kCVPixelBufferPixelFormatTypeKey];


// If you wish to cap the frame rate to a known value, such as 15 fps, set
// minFrameDuration.

//output.minFrameDuration=CMTimeMake（1,1）

}

//从样本缓冲区数据创建UIImage -（UIImage*）imageFromSampleBuffer:（CMSampleBufferRef）sampleBuffer{ NSLog（@“图片越来越多”）； CVImageBufferRef imageBuffer=CMSampleBufferGetImageBuffer（sampleBuffer）； //锁定像素缓冲区的基址 CVPixelBufferLockBaseAddress（imageBuffer，0）

}

//在写入样本缓冲区时调用的委托例程 -（无效）captureOutput:（AVCaptureOutput*）captureOutput didOutputSampleBuffer:（CMSampleBufferRef）sampleBuffer fromConnection：（AVCaptureConnection*）连接{ //从样本缓冲区数据创建UIImage NSLog（@“图片越来越多”）； UIImage*image=[self-imageFromSampleBuffer:sampleBuffer]

//[self.delegate cameraCaptureGotFrame:image]； }

现在代理“captureOutput”没有收到调用。 我不知道我哪里做错了。这对我有帮助。提前谢谢

// Configure the session to produce lower resolution video frames, if your
// processing algorithm can cope. We'll specify medium quality for the
// chosen device.
session.sessionPreset = AVCaptureSessionPresetLow;

// Find a suitable AVCaptureDevice
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
[device lockForConfiguration:nil];
[device setTorchMode:AVCaptureTorchModeOn];  // use AVCaptureTorchModeOff to turn off
[device unlockForConfiguration];
// Create a device input with the device and add it to the session.
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device
                                                                    error:&error];
if (!input) {
    // Handling the error appropriately.
}
[session addInput:input];

// Create a VideoDataOutput and add it to the session
AVCaptureVideoDataOutput *output = [[AVCaptureVideoDataOutput alloc] init] ;

dispatch_queue_t queue = dispatch_queue_create("MyQueue", NULL);
[output setSampleBufferDelegate:self queue:queue];
dispatch_release(queue);

// Specify the pixel format
output.videoSettings =
[NSDictionary dictionaryWithObject:
 [NSNumber numberWithInt:kCVPixelFormatType_32BGRA]
                            forKey:(id)kCVPixelBufferPixelFormatTypeKey];


// If you wish to cap the frame rate to a known value, such as 15 fps, set
// minFrameDuration.

// Start the session running to start the flow of data
  NSLog(@"session is going to start at here");
[session startRunning];

// Assign session to an ivar.
//[self setSession:session];

// Get the number of bytes per row for the pixel buffer
size_t bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer);
// Get the pixel buffer width and height
size_t width = CVPixelBufferGetWidth(imageBuffer);
size_t height = CVPixelBufferGetHeight(imageBuffer);

// Create a device-dependent RGB color space
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
if (!colorSpace)
{
    NSLog(@"CGColorSpaceCreateDeviceRGB failure");
    return nil;
}

// Get the base address of the pixel buffer
void *baseAddress = CVPixelBufferGetBaseAddress(imageBuffer);
// Get the data size for contiguous planes of the pixel buffer.
size_t bufferSize = CVPixelBufferGetDataSize(imageBuffer);

// Create a Quartz direct-access data provider that uses data we supply
CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, baseAddress, bufferSize,
                                                          NULL);
// Create a bitmap image from data supplied by our data provider
CGImageRef cgImage =
CGImageCreate(width,
              height,
              8,
              32,
              bytesPerRow,
              colorSpace,
              kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Little,
              provider,
              NULL,
              true,
              kCGRenderingIntentDefault);
CGDataProviderRelease(provider);
CGColorSpaceRelease(colorSpace);

// Create and return an image object representing the specified Quartz image
UIImage *image = [UIImage imageWithCGImage:cgImage];
CGImageRelease(cgImage);

CVPixelBufferUnlockBaseAddress(imageBuffer, 0);

return image;