RGB output from composite PPU

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Drakon
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Re: RGB output from composite PPU

Post by Drakon »

HardWareMan wrote:
Drakon wrote:Does your circuit mix in pins 45 / 46 of the famicom cartridge slot so games with added audio chips still get the audio mixed in?
Yes, it does. And I also cut off #45 from internal circuit to prevent additional noise.
Yeah that makes sense. The audio circuits I install have you cut the traces to pins 45 and 46 and isolate them from the famicom pcb.
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yxkalle
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Re: RGB output from composite PPU

Post by yxkalle »

This is great! Why not cooperate with Jonathon (jwdonal) and add HQ2X filtering into your project? Not that I have anything against pixels, but I really like the results. :D Just a thought...
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Drakon
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Re: RGB output from composite PPU

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yxkalle wrote:This is great! Why not cooperate with Jonathon (jwdonal) and add HQ2X filtering into your project? Not that I have anything against pixels, but I really like the results. :D Just a thought...
Oh goodness please no. Do that sort of thing externally, I love my pixels and my scanlines.
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tokumaru
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Re: RGB output from composite PPU

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HQ2X completely blotches the picture. You simply can't create detail that isn't there without getting it wrong 80% of the time... Sure, it may look good here and there, but generally it looks like crap.
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yxkalle
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Re: RGB output from composite PPU

Post by yxkalle »

Drakon wrote:
yxkalle wrote:This is great! Why not cooperate with Jonathon (jwdonal) and add HQ2X filtering into your project? Not that I have anything against pixels, but I really like the results. :D Just a thought...
Oh goodness please no. Do that sort of thing externally, I love my pixels and my scanlines.
This is only possible when it outputs at four times the NES resolution (512x448, VGA and such. Like in the screenshots). So you don't have to be afraid as I guess you are going to use it on an ordinary TV through S-video. ...And there's nothing wrong in having options, you know. ;)
tokumaru wrote:HQ2X completely blotches the picture. You simply can't create detail that isn't there without getting it wrong 80% of the time... Sure, it may look good here and there, but generally it looks like crap.
I'm just thinking of ways to get those extra pixels to use. I'm not saying that it's for everyone, but some people will like it and use it. If this ever becomes a real product I would even call it a sell point! Again, options are good!
Last edited by yxkalle on Sun Jan 27, 2013 9:44 pm, edited 2 times in total.
tepples
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Re: RGB output from composite PPU

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yxkalle wrote:This is only possible when it outputs at four times the NES resolution (512x448, VGA and such. Like in the screenshots).
Output at twice the NES resolution is possible through interlaced video. But that may not be cheap to do because converting slightly-too-fast 240p video to 480i properly requires a 2-frame buffer.
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yxkalle
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Re: RGB output from composite PPU

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tepples wrote: Output at twice the NES resolution is possible through interlaced video. But that may not be cheap to do because converting slightly-too-fast 240p video to 480i properly requires a 2-frame buffer.
Wouldn't that cut the frame rate in half? I like it progressive. :)
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Re: RGB output from composite PPU

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yxkalle wrote:Wouldn't that cut the frame rate in half?
Technically it would, as each interlaced frame is made of two fields. But objects can still move between the first field and the second field of a frame, showing motion with the same fluidity as 240p. Objects that move between fields simply appear less detailed while they are in motion, but no less detailed than they would have been at 240p. This can be seen in any live or videotaped television programming, which is presented at 60 unique fields per second, especially live sports. It can also be seen in games for sixth-generation (Dreamcast, PlayStation 2, GameCube, Xbox) or later consoles and in PC games played through a PC to TV adapter.
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yxkalle
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Re: RGB output from composite PPU

Post by yxkalle »

tepples wrote: Technically it would, as each interlaced frame is made of two fields. But objects can still move between the first field and the second field of a frame, showing motion with the same fluidity as 240p. Objects that move between fields simply appear less detailed while they are in motion, but no less detailed than they would have been at 240p. This can be seen in any live or videotaped television programming, which is presented at 60 unique fields per second, especially live sports. It can also be seen in games for sixth-generation (Dreamcast, PlayStation 2, GameCube, Xbox) or later consoles and in PC games played through a PC to TV adapter.
I guess you could do it like the 240p but every even frame you show only the 2 * N scanlines and every odd you show 2 * N + 1. I wonder how that would look? I don't think you need a buffer for a whole frame though, just a couple of scanlines.
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Re: RGB output from composite PPU

Post by tepples »

yxkalle wrote:I guess you could do it like the 240p but every even frame you show only the 2 * N scanlines and every odd you show 2 * N + 1. I wonder how that would look?
It'd look slightly jumpy up and down at 30 Hz. Some GameCube games solve it by using a 3-tap deflicker filter, which mixes 1 part previous scanline, 2 parts current scanline, and 1 part next scanline. Should I run tests to show how hq2x + interlace + deflicker would look compared to 240p?
I don't think you need a buffer for a whole frame though, just a couple of scanlines.
You'd need the buffer for the whole frame because during one frame, the NES outputs 524 lines while you need to output 525.
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yxkalle
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Re: RGB output from composite PPU

Post by yxkalle »

tepples wrote: It'd look slightly jumpy up and down at 30 Hz. Some GameCube games solve it by using a 3-tap deflicker filter, which mixes 1 part previous scanline, 2 parts current scanline, and 1 part next scanline. Should I run tests to show how hq2x + interlace + deflicker would look compared to 240p?
I see... :) You could try that (would be interesting), but I guess you don't get a real feeling for how it looks without hooking your computer up to an old CRT TV first.
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Re: RGB output from composite PPU

Post by tepples »

I tried it on a frame from my NROM project template:

Image

Please forgive the tearing in browsers that don't synchronize GIF animation to the vertical blank.
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mikejmoffitt
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Re: RGB output from composite PPU

Post by mikejmoffitt »

All of them look almost as good as the top left :?
Other options are a good idea for those who want to try them, but be sure to maybe leave in the option of unscaled, unmaimed 240p output to match the original, or at least 480p with a simple nearest neighbor scaling.
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yxkalle
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Re: RGB output from composite PPU

Post by yxkalle »

tepples wrote:I tried it on a frame from my NROM project template:

Image

Please forgive the tearing in browsers that don't synchronize GIF animation to the vertical blank.
I can clearly see the difference, but I'm not sure if I think it's worth the trouble. The blurring is kinda off-putting. ;)
mikejmoffitt wrote:All of them look almost as good as the top left :?
Other options are a good idea for those who want to try them, but be sure to maybe leave in the option of unscaled, unmaimed 240p output to match the original, or at least 480p with a simple nearest neighbor scaling.
Ofcourse! I don't want him to remove options... Talking about 480p, I would probably just use nearest neighbor scaling (and maybe scanline simulation) most of the time anyway.
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Re: RGB output from composite PPU

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yxkalle wrote:This is great! Why not cooperate with Jonathon (jwdonal) and add HQ2X filtering into your project? Not that I have anything against pixels, but I really like the results. :D Just a thought...
I'm personally not a big fan of those type of filters, but maybe some day.
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