AVFoundation, AVCaptureMetadataOutput capturing screenshot

Question

I am using AVCaptureMetadataOutput in order to use iOS QRCode,barcode scanning feature. This works well, and I get the result of scanning through AVCaptureMetadataOutput delegate method

-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{

But I don't know how to capture the image of scanned qrcode,barcode with the data I have in this delegate.

Answer 1

I have captured image while scanning QRCode like this:

1) Firstly add property of AVCaptureStillImageOutput's

@property (strong, nonatomic) AVCaptureStillImageOutput *stillImageOutput;

2) Add session preset in AVCaptureSession after initializing it

[self.session setSessionPreset:AVCaptureSessionPreset640x480];

3) Now add AVCaptureStillImageOutput's as output in AVCaptureSession

// Prepare an output for snapshotting
self.stillImageOutput = [AVCaptureStillImageOutput new];
[self.session addOutput:self.stillImageOutput];
self.stillImageOutput.outputSettings = @{AVVideoCodecKey: AVVideoCodecJPEG};

4) Make add below code to capture scanned image in delegate method captureOutput:didOutputMetadataObjects:fromConnection:connection

 __block UIImage *scannedImg = nil;
// Take an image of the face and pass to CoreImage for detection
AVCaptureConnection *stillConnection = [self.stillImageOutput connectionWithMediaType:AVMediaTypeVideo];
[self.stillImageOutput captureStillImageAsynchronouslyFromConnection:stillConnection completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error) {
    if(error) {
        NSLog(@"There was a problem");
        return;
    }

    NSData *jpegData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];

    scannedImg = [UIImage imageWithData:jpegData];
    NSLog(@"scannedImg : %@",scannedImg);
}];

For reference use CodeScanViewController

Thats it @Enjoy