QR code tweaks
Invert
Makes a QR code designed for a black background.
Rotation
0°
90°
180°
270°
Rotates the QR code before adding the image, which can help move the required patterns to less obtrusive places.
Mask
Mask 0
Mask 1
Mask 2
Mask 3
Mask 4
Mask 5
Mask 6
Mask 7
There are eight different XOR masks that can be applied to QR codes. The choice is fairly arbitrary but picking the right one might happen to give you a nicer pattern of data pixels to work with.
Diffusion settings
Diffuse data points
Uses error diffusion when adding the data squares — this makes the image worse and the only reason to turn this off is for demo purposes.
Diffuse free points
Use error diffusion to dither the image rather than simply thresholding it.
Include image
If disabled, just generate a regular QR code with no image in it.
Subpixel ratio
How many times to subdivide each pixel of the QR code. Eg, if this is 3 then each block of the QR code will be replaced by 9 (3²) pixels, the middle one of which contains the data. If it's an even number then the middle 4 pixels will contain the data.
Proportion of pixels to change
If you have enough error correction in the image, you may be able to change a few data pixels without breaking the QR code. If this is set to 0.01 then we will change the worst 1% of data pixels. This can easily render the code unscannable but might help in some cases.