AVCaptureMetadataOutput Inverse Colors - ios

Question

I am making an app that scans a barcode that inverted color (black background & white bars). I have to use AVFoundation. Currently, I am using AVCaptureMetadataOutput. I can get it to work perfectly with a normal barcode. I need to invert the color on the white -> black & black -> white etc. Can I add a CIColorInvert to the Input in AVCaptureSession
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.
mCaptureSession = [[AVCaptureSession alloc] init];
AVCaptureDevice *videoCaptureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
NSError *error = nil;
AVCaptureDeviceInput *videoInput = [AVCaptureDeviceInput deviceInputWithDevice:videoCaptureDevice error:&error];
if([mCaptureSession canAddInput:videoInput]){
[mCaptureSession addInput:videoInput];
} else {
NSLog(#"Could not add video input: %#", [error localizedDescription]);
}
// set up metadata output and this class as its delegate so that if metadata (barcode 39) is detected it will send the data to this class
AVCaptureMetadataOutput *metadataOutput = [[AVCaptureMetadataOutput alloc] init];
if([mCaptureSession canAddOutput:metadataOutput]){
[mCaptureSession addOutput:metadataOutput];
[metadataOutput setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
[metadataOutput setMetadataObjectTypes:#[AVMetadataObjectTypeCode39Code]];
} else {
NSLog(#"Could not add metadata output");
}
// sets up what the camera sees as a layer of the view
AVCaptureVideoPreviewLayer *previewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:mCaptureSession];
//CGRect frame = CGRectMake(0.0 - 50, 0.0, 1024.0, 1024.0 + 720.0);
CGRect bounds=self.view.layer.bounds;
previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
previewLayer.bounds=bounds;
previewLayer.position=CGPointMake(CGRectGetMidX(bounds), CGRectGetMidY(bounds));
NSArray *filters = [[NSArray alloc] initWithObjects:[CIFilter filterWithName:#"CIColorInvert"], nil];
[previewLayer setFilters:filters];
//[previewLayer setFrame:self.view.bounds];
[self.view.layer addSublayer:previewLayer];
//starts the camera session
[mCaptureSession startRunning];
}