What is the name of the technique or optical effect in this image, where the appearance of the image seems to change based on size, distance, or even by squinting?

I’m not sure if it has an official name—maybe “illusion diffusion”? Here’s a tool I use:

Great,That’ is the real deal.

They use Controlnet’s QR Code Monster on Stable Diffusion to make the generated image conform to a simpler, high-contrast picture.

Stable Diffusion with QR ControlNet.

It is called Optical illusion.