Detection qr code bounds IOS 7

Question

I have qr reader with new ios 7.

I need detect where is the code on the screen (corners).

I use AVMetadataObject to it.

Have you got any idea, how to detect it?

- (void)captureOutput:(AVCaptureOutput *)captureOutput
didOutputMetadataObjects:(NSArray *)metadataObjects
       fromConnection:(AVCaptureConnection *)connection
{
    for (AVMetadataObject *metadata in metadataObjects)
    {

               AnimationView *cv = [[AnimationView alloc]initWithFrame:self.livevideo.bounds]; 
      [cv setBackgroundColor:[UIColor clearColor]];
      cv.rectXY = metadata.bounds;


[location addSubview:cv];


        if ([metadata.type isEqualToString:AVMetadataObjectTypeQRCode])
        {
            NSString *code =[(AVMetadataMachineReadableCodeObject *)metadata stringValue];
            NSLog(@"Read QRCODE %@", code);
        }
    }
}