Color analysis between different emulators/editors
Posted: Wed May 23, 2018 8:10 am
So I'm finally getting around to developing my own Palette/Sprite Editor. (Currently prototyping in Python using the PyQt library. Since I run Linux I intend to make it cross-platform.) One of the things I'm currently trying to address is determining how best to represent (or approximate) 9-bit RGB/BGR values as modern day 24-bit RBG values.
I was curious if there was an established community standard when representing Genesis/MegaDrive colors on modern hardware? (Gotta tread lightly, don't want to start another Colors War... Haha!)
Sigflup's Mega Happy Sprite editor (among other editors,) scales values 0-7 by 36. (floor[255 / 7] = 36.) This gives a "pure white" of 0xFCFCFC.
I can replicate the Regen emulator's color representation by scaling values by 32. This gives a "pure white" of 0xE0E0E0. (Gens/GS gives 0xE0E8E0 for whatever reason... All green values seems to be off scaled in Gens/GS compared to Regen.)
The BlastEm emulator gives a genuine "pure white" of 0xFFFFFF. (Mapping table is described here: viewtopic.php?p=27360#p27360)
Kega-Fusion's color representation can be replicated by the following:
mapped_color = (value * 32) + value. This gives a "pure white" of 0xE7E7E7.
Tests on the video timings back in 2010 suggest that the color stepping/scale is actually 34: viewtopic.php?p=10067#p10067 This would give a "pure white" of 0xEEEEEE.
In the picture below I'm using the TANGLEWOOD 0.8.01 Demo as a color reference between the emulators and the official clip of the demo on YouTube: https://www.youtube.com/watch?v=59KW8xT74eo (Not sure if the Demo was captured live or emulated.)
The Cyan-like color between the trees in the background is represented by the following:
Edit: ...Annnddd I just realized it may have been better to place this in the "Video Display Processor" forum. If it seems more appropriate there, would a Mod please move this? Thanks!
I was curious if there was an established community standard when representing Genesis/MegaDrive colors on modern hardware? (Gotta tread lightly, don't want to start another Colors War... Haha!)
Sigflup's Mega Happy Sprite editor (among other editors,) scales values 0-7 by 36. (floor[255 / 7] = 36.) This gives a "pure white" of 0xFCFCFC.
I can replicate the Regen emulator's color representation by scaling values by 32. This gives a "pure white" of 0xE0E0E0. (Gens/GS gives 0xE0E8E0 for whatever reason... All green values seems to be off scaled in Gens/GS compared to Regen.)
The BlastEm emulator gives a genuine "pure white" of 0xFFFFFF. (Mapping table is described here: viewtopic.php?p=27360#p27360)
Kega-Fusion's color representation can be replicated by the following:
mapped_color = (value * 32) + value. This gives a "pure white" of 0xE7E7E7.
Tests on the video timings back in 2010 suggest that the color stepping/scale is actually 34: viewtopic.php?p=10067#p10067 This would give a "pure white" of 0xEEEEEE.
In the picture below I'm using the TANGLEWOOD 0.8.01 Demo as a color reference between the emulators and the official clip of the demo on YouTube: https://www.youtube.com/watch?v=59KW8xT74eo (Not sure if the Demo was captured live or emulated.)
- Screenshot from 2018-05-19 22-44-36.png (212.32 KiB) Viewed 6866 times
- YouTube clip: 0x13B1A5
- BlastEm: 0x31CEAE
- Gens/GS: 0x20C8A0
- Regen: 0x20C0A0
- Kega-Fusion: 0x21C6A5
Edit: ...Annnddd I just realized it may have been better to place this in the "Video Display Processor" forum. If it seems more appropriate there, would a Mod please move this? Thanks!
