I need to use both AVCaptureVideoDataOutput and AVCaptureMetadataOutput - ios

Question

I'm writing an app that needs to look at the raw video (custom edge detection etc) and use the meta data barcode reader.
even though the AVCaptureSession has an addOutput: method instead of setOutput: method, that's exactly what it's doing - first one in wins.
if I add AVCaptureVideoDataOutput as output first - it's delegate gets called.
if I add AVCaptureMetadataOutput as output first - it's delegate gets called.
Has anyone figured out a way around this?
short of removing the other one every other frame?

Answer 1

I was able to add both AVCaptureVideoDataOutput and AVCaptureMetadataOutput.
NSError *error = nil;
self.captureSession = [[AVCaptureSession alloc] init];
[self.captureSession setSessionPreset:AVCaptureSessionPresetHigh];
// Select a video device, make an input
AVCaptureDevice *captureDevice;
AVCaptureDevicePosition desiredPosition = AVCaptureDevicePositionFront;
// Find the front facing camera
for (AVCaptureDevice *device in [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo]) {
if ([device position] == desiredPosition) {
captureDevice = device;
break;
}
}
AVCaptureDeviceInput *deviceInput = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:&error];
if (!error) {
[self.captureSession beginConfiguration];
// add the input to the session
if ([self.captureSession canAddInput:deviceInput]) {
[self.captureSession addInput:deviceInput];
}
AVCaptureMetadataOutput *metadataOutput = [AVCaptureMetadataOutput new];
if ([self.captureSession canAddOutput:metadataOutput]) {
[self.captureSession addOutput:metadataOutput];
self.metaDataOutputQueue = dispatch_queue_create("MetaDataOutputQueue", DISPATCH_QUEUE_SERIAL);
[metadataOutput setMetadataObjectsDelegate:self queue:self.metaDataOutputQueue];
[metadataOutput setMetadataObjectTypes:#[AVMetadataObjectTypeQRCode]];
}
self.videoDataOutput = [AVCaptureVideoDataOutput new];
if ([self.captureSession canAddOutput:self.videoDataOutput]) {
[self.captureSession addOutput:self.videoDataOutput];
NSDictionary *rgbOutputSettings = [NSDictionary dictionaryWithObject:[NSNumber numberWithInt:kCMPixelFormat_32BGRA] forKey:(id)kCVPixelBufferPixelFormatTypeKey];
[self.videoDataOutput setVideoSettings:rgbOutputSettings];
[self.videoDataOutput setAlwaysDiscardsLateVideoFrames:YES];
self.videoDataOutputQueue = dispatch_queue_create("VideoDataOutputQueue", DISPATCH_QUEUE_SERIAL);
[self.videoDataOutput setSampleBufferDelegate:self queue:self.videoDataOutputQueue];
[[self.videoDataOutput connectionWithMediaType:AVMediaTypeVideo] setEnabled:YES];
}
[self.captureSession commitConfiguration];
[self.captureSession startRunning];
}