QR code quality low when saved as file

[rugk]

When you save the QR code as a file with the built-in function and zoom into it you see that the quality of the image is quite low:

It is not a real black/white.

However if you just screenshot the QR code showed when displaying it, it looks much better.

You may consider even reducing the size of the saved image and save it with a low color depth and if you use only 2bits (in case this is possible) this would also fix this problem. 😃

Related: #23