ios capturing image using AVFramework

Add the following line

output.minFrameDuration = CMTimeMake(5, 1);

below the comment

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

but above the

[session startRunning];

Edit

Use the following code to preview the camera output.

AVCaptureVideoPreviewLayer *previewLayer = [AVCaptureVideoPreviewLayer layerWithSession:session];UIView *aView = self.view;CGRect videoRect = CGRectMake(0.0, 0.0, 320.0, 150.0);previewLayer.frame = videoRect; // Assume you want the preview layer to fill the view.[aView.layer addSublayer:previewLayer];

Edit 2:Ok fine..

Apple has provided a way to set the minFrameDuration here

So now, use the following code to set the frame duration

AVCaptureConnection *conn = [output connectionWithMediaType:AVMediaTypeVideo];if (conn.supportsVideoMinFrameDuration)    conn.videoMinFrameDuration = CMTimeMake(5,1);if (conn.supportsVideoMaxFrameDuration)    conn.videoMaxFrameDuration = CMTimeMake(5,1);

Be careful - callback from AVCaptureOutput is posted in dispatch queue you specified. I saw you perform UI updates from this callback, and that is wrong. You should perform them only in main queue. E.g.

- (void)captureOutput:(AVCaptureOutput *)captureOutput     didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer        fromConnection:(AVCaptureConnection *)connection{     NSLog(@"captureOutput: didOutputSampleBufferFromConnection");    // Create a UIImage from the sample buffer data    UIImage *image = [self imageFromSampleBuffer:sampleBuffer];    dispatch_async(dispatch_get_main_queue(), ^{    //< Add your code here that uses the image >        [self.imageView setImage:image];        [self.view setNeedsDisplay];    }} 

And here is a Swift version of imageFromSampleBuffer function:

func imageFromSampleBuffer(sampleBuffer:CMSampleBuffer!) -> UIImage {    let imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer)!    CVPixelBufferLockBaseAddress(imageBuffer, 0)    let baseAddress = CVPixelBufferGetBaseAddress(imageBuffer)    let bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer)    let width = CVPixelBufferGetWidth(imageBuffer)    let height = CVPixelBufferGetHeight(imageBuffer)    let colorSpace = CGColorSpaceCreateDeviceRGB()    let bitmapInfo:CGBitmapInfo = [.ByteOrder32Little, CGBitmapInfo(rawValue: CGImageAlphaInfo.PremultipliedFirst.rawValue)]    let context = CGBitmapContextCreate(baseAddress, width, height, 8, bytesPerRow, colorSpace, bitmapInfo.rawValue)    let quartzImage = CGBitmapContextCreateImage(context)    CVPixelBufferUnlockBaseAddress(imageBuffer, 0)    let image = UIImage(CGImage: quartzImage!)    return image}

Above working for me with following video settings:

videoDataOutput = AVCaptureVideoDataOutput()videoDataOutput?.videoSettings = [kCVPixelBufferPixelFormatTypeKey:Int(kCVPixelFormatType_32BGRA)]            videoDataOutput?.setSampleBufferDelegate(self, queue: queue)