Worked as described

This app allows your Mac camera to scan QR codes. Images can also be dropped onto the application and read without the camera.

The QR code images needed to be reasonable size to be read. I found 100px, or about 45mm, to be the smallest code readable through my Mac camera.

Smaller codes could be read with a camera phone.

This app is only for your computer.

AndyBrewer about QR Code Scanner