Thank you very much for the extremely detailed explanation.
You’re absolutely right — with the current specifications, the brightness levels aren’t the official ones, but simply the result of dividing 255 by 7:
0, 36, 73, 109, 146, 182, 219, 255.
Since the core library this app uses isn’t one I created myself, making changes may be difficult, but I’ll think about possible approaches.
As for counting the number of unique tiles in the image after Qualetize, I think that feature should be relatively easy to implement.
I really appreciate your feedback — it’s incredibly helpful and motivating.
Thank you again for taking the time to point this out.