How do I use the metadataOutputRectOfInterestForRect method and rectOfInterest property to scan a specific area? (QR Code)

Question

I am building a QR code scanner with Swift and everything works in that regard. The issue I have is that I am trying to make only a small area of the entire visible A

Answer 1

I wrote the following:

videoPreviewLayer?.frame = view.layer.bounds
videoPreviewLayer?.videoGravity = AVLayerVideoGravityResizeAspectFill

And this worked for me, but I still don't know why.