To Manuel... an idea for OpenMSX

Champion (454)

11-06-2007, 10:50

Hey Manuel, have you ever seen this video filters?

http://www.slack.net/~ant/libs/ntsc.html

These filters does simulate the noises you would see watching a game on an old TV set connected to a real console/computer; Many of the new emulators released by Richard Bannister on Mac OS X now supports these filters and with no offence to the marvellous work of Daniel Vik, IMHO they work better than the Y/C Noisy cable simulation of BlueMSX. Some filters are optimized for some specific machines (such as the NES, SNES and the Master System); they're written in portable C and released under the LGNU License.

For example, here are two comparisons between a filtered screen and a normal/interpolated screen with no filters :

blargg.fileave.com/ntsc-vs-palette/ghosts_and_goblins.png

blargg.fileave.com/ntsc-vs-palette/snakes_revenge.png

Obviously I don't know if they could be easily implemented into OpenMSX, or if you have already something better that you are proud of... I'd be glad if you just give a look to that page and see if they could be a nice addition for OpenMSX or not.

By hap

Paragon (2042)

11-06-2007, 12:44

My emulators use blargg's NTSC library, it's the only "filter" I like. Instead of faking artifacts (or making up new ones like 2xSai) it simulates NTSC composite video, MSX1 example:
home.planet.nl/~haps/crap/meisei.png
The above image uses the TI 99/4A NTSC library (same videochip as MSX1), MSX2 emulators are probably better off using sms_ntsc, implementation is easy.

By wolf_

Ambassador_ (10095)

11-06-2007, 12:49

hm.. the colors around the white (text, platform etc.) are a bit too much I think.

By Samor

Prophet (2171)

11-06-2007, 12:52

well, it DOES imitate Never The Same Color, not PAL
..seems about right to me.

By hap

Paragon (2042)

11-06-2007, 12:56

Yes, the red/green/blue artifacts at the bottom of the pic are accurate for NTSC. Here's an example of a game using composite artifacts at its favour:
home.planet.nl/~haps/crap/meisei2.png
left:RGB, right:NTSC (the ice next to the boulder)

By NYYRIKKI

Enlighted (6033)

11-06-2007, 14:06

In cesco example I can first time see serrated picture edges emulated. I like that, because I think it is visually most important effect that composite NTSC causes.

By hap

Paragon (2042)

11-06-2007, 14:46

You mean the picture on the bottom left? It's the NES, that specific artifact doesn't apply to the TMS9918. Download the libraries for detailed information, they're well documented.

By Manuel

Ascended (19314)

11-06-2007, 21:46

Good idea, I'll post it in our Feature Request tracker, something you could also have done yourself, by the way (It's a bit more efficient than posting it on MRC...)

Note that except for that 'color noise', you can already fake a lot old monitorness using settings like: blur, glow, noise, scanline, gamma, contrast, brightness and color_matrix.

By cesco

Champion (454)

11-06-2007, 21:51

...something you could also have done yourself, by the way (It's a bit more efficient than posting it on MRC...)

Well, you have answered me as well...

By Manuel

Ascended (19314)

11-06-2007, 22:10

Note that we're currently looking at some sound libs of the same guy

By hap

Paragon (2042)

11-06-2007, 22:58

You mean band limited sound synthesis? That would probably work well for the AY-8910.
I think I've brought that up before on this forum, though without reaction