3 ms·
I think the JPEGs could be useful without converting to ASCII art. Could you use JPEG decoding to convert hashes into small and visually-distinct images?
by mleonhard 5y ago
I think the JPEGs could be useful without converting to ASCII art. Could you use JPEG decoding to convert hashes into small and visually-distinct images?
- dragontamer 5y agoThe DCT of the JPEG algorithm converts all images into the sum of these 256-distinct images: https://upload.wikimedia.org/wikipedia/commons/2/23/Dctjpeg.png https://upload.wikimedia.org/wikipedia/commons/2/23/Dctjpeg.... Those 64-images are called the "coefficients of a Discrete Fourier Transform", and the magic of FFT means that all images can be represented by a sum of those 64 images. The images on the bottom right are "harder" for the eye to recognize, while the images on the top-left are "easier" for the eye to recognize. JPEG standard spends "more bits" on the top left images, and "fewer bits" on the bottom right images. ---------- Our controls are as follows: we can multiply an image with a value (ex: 4-bits give us 0Coefficient(0,0) through 15Coefficient(0,0)). We should give more bits to the ones our eyes can see (ex: more bits to Coefficient(0,0)), while giving fewer bits to the bottom-right coefficients / images (ex: the bottom right checkerboard pattern looks very similar to the checkerboards around it. We probably want to spend 0-bits on that pattern, never to use it at all so that our eyes can distinguish our patterns more)