A small update.
Get it here:
ham_convert_0.9.7.zip
Mirror (all versions)
Changelog:
- Color mapping is now performed using the complex CIEDE2000-based function for a more accurate color reproduction. This color distance function calculates subjectively closest color based on the study of the human perception of colors (better suited for HAM or palettes consisting of a low number of colors or fixed palettes). Due to its subjective nature it’s not well suited for dithering and there may be some rare anomalies while using dithering. The older function is also available.
- MSX1 screen 2 – 2 colors out of 15 on every 8×1 block.
- Faster ZX, C64 and Plus/4 conversion.
- 4-color Plus/4 modes (slow, experimental).
- CIEDE2000 used for color mapping and block palette calculation in ZX, C64, Plus/4 and MSX modes. As described above its not suitable for dithering so the older one is used instead.
- Various bug fixes.
Just out of curiosity, would be possible easily add things like batch conversion or even .anim output file to the tool?
Anyway, really nice tool!
It should be possible to add it in the future.
Awesome, thanks for answer.
One more little question about “fakemode”. Is possible use similar technique with Amiga compatible modes (AGA, HAM6/8 maybe EHB, OCS/ECS as well) or better say apply it on them as optional pass during conversion? Also will be Amiga able utilize this trick or it’s just pure PC HW related?
Fakemode was just a 256-color mode with a palette consisting of 64 shades of red, 64 shades of green and 64 shades of blue. This gives an illusion of 262144 colors at the cost of 3xlower vertical resolution or some artefacts. Amiga can change a palette between lines so it can use some sort of fakemode variation. Ocs Amigas were too slow to change all 16 colors every line in hires modes. In lores it was possible.
Again, thanks for answer.
Wll, if i understood it well AGA chipset should be definitely possible use the fakemode in fact exactly same as PC VGA and real Amiga 1200 and above should be able utilize it in usable framerate.. theoretically.
Just found 2 color quantization algorithms with very nice results – “libimagequant” and “scolorq”.
libimagequant: https://pngquant.org/lib/
scolorq: http://www.cs.berkeley.edu/~dcoetzee/downloads/scolorq/
Maybe you may want integrate them to ham_convert as well. They both provides surprisingly good results especially in reduction to 16 or 32 colors.
Thank you. I’ll do some research.