QRImage is a web app to generate QR codes with images.
Works better for square images (use an
editor as
needed).
Bit size:
Larger sizes hide more of the image, but are easier to
scan. I found that a size of 30 works well.
Error Correction:
Higher level of error correction makes bigger qr codes, but
also allows you to hide more of the QR code. The former is
more relevant to this app.
Border Size:
Size of white border around QR code. Typically need some
border around the code, but depending on your use case you
can get rid of it.