[vajenetehais]

I've found it really interesting and it works great to also copy documents without altering quality.

About notes, there is one thing that bothers me. It's highlighted text. Colors are clear and are always filtered. Blue and green highlighter are ok, but pink or yellow ones are another story. That's inherent to the method used and as far I know (and tried) can't be fixed with adjusted thresholds.

It's nonetheless a great tool and I've automated its use for every scan I do.

[Syzygies]

Yes. Compression and recognition are two sides of the same coin. A serious compression algorithm adapted to hand-drawn notes would evolve a spatial model for the background, and be forced to spawn subprocesses for highlighted background. Normalize, and one gets clean highlighting.