We got the live barcode reading working with the AVRecorder functions in MBS FileMaker Plugin. We now have the option to automatically feed the recorded images to the CoreImage detector to find QRCodes:
This works nice and can optionally triggers a script for a new barcode. So you should be able to have your users hold a QRCode in front of the iPhone or Mac camera and get the barcodes coming in. The advantage is that we do the processing and detection on a preemptive thread, so it runs in background and doesn't block FileMaker from doing other things.
Of course you always get current frame with AVRecorder.CaptureStillPhoto and pass it to OCR.SetImage for text recognition or Barcode.Detect to find different barcodes yourself. That even works on Windows.
Coming soon with next prerelease of MBS Plugin 8.4.