Snes9x RGB NTSC filter not dark enough?

twipley · Post by **twipley** » Sun Feb 27, 2011 5:25 pm

I was comparing ZSNES with Snes9x on the matter of the RGB-preset NTSC filter. The graphics generated by Snes9x look not as dark as the ZSNES ones!

I was wondering which program was in its wrong.

Note that the ZSNES RGB filter suffers from a bug by default, which should be remediated through the instructions featured in the following thread: http://board.zsnes.com/phpBB3/viewtopic.php?f=2&t=11775

The comparison between Snes9x and ZSNES should thus be effected only after the bleed setting is set to -100 (which is configuration-file repairable).

OV2 · Post by **OV2** » Sun Feb 27, 2011 7:39 pm

Snes9x uses the default blitter implementation provided by blargg with his library, zsnes uses a custom blitter that darkens every second scanline by 25%.

twipley · Post by **twipley** » Sun Feb 27, 2011 8:18 pm

Not that I do not like the graphics as outputted by ZSNES, but is there a reason why it is using such a "custom" blitter instead of the default one?

Otherwise thanks for the info; that fully answers my initial interrogations.

OV2 · Post by **OV2** » Sun Feb 27, 2011 8:30 pm

You'll have to ask the zsnes devs about this. The source only states "custom blitter that doubles image height and darkens every other row".

EDIT:
I just remembered that blargg's filters output half-height images, they need to be resized to get correct height. Every second line is darkened to simulate the scanlines look - snes9x (win) uses 12% as in blargg's sample code, zsnes uses 25%.