Accurate NTSC output from Raspberry Pi Composite out in 240p, testing Pi against real NES hardware
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- čas přidán 27. 09. 2020
- Trying to get an accurate video signal from the raspberry Pi through the composite out is kinda tricky, it's not as simple as getting 240P mode to work unfortunately.
info on getting 240p to work
retropie.org.uk/forum/topic/1...
I found these 4 things got me pretty accurate results emulating NES (not worrying about colors really)
-240p screen format
-640x480 render resolution for the screen format
-717x552 (5 x -40 offset) retroarch framebuffer for the NES output
-bilinear filtering set to off
These settings are very specific and probably only work good for NES emulation.
I planned on just applying this to my SNES because I don't have one of those but the output doesn't look good like that and it looks better at the default settings than NES ever did
The NES has a native resolution of 256x240 and uses a 240p screen mode.
The SNES uses 256x224 and 512x448, but always used a 240p screen mode except for one of two games that were 480i. Maybe the original SNES did use a bilinear filtering when outputting 512x448 in 240p - Věda a technologie
This is a really useful video. Thanks for sharing. I'm currently trying to get decent composite signal out of my pie too.
I wound up using a new retropie image and I'm not entirely sure what's going on, I imagine it has something to do with overscan cropping, but now these size settings are too big to match the NES accurately. I might make a follow up video about my experience with the newer retropie.
Thanks for that tip, I'll have to try it, I did get composite out of my Pi4 running RetroPie but it was 480i only and 240p Test Suite showed some rather concerning issues with video quality, in my current setup it's very clear there's some kind of double resolution conversion going on. Stripes and checkerboard patterns become a huge rainbow mess that I've never seen with the MiSTer, even when using it with less than ideal RGB to composite video converters.
yeah, I dont know if analog output from the Pi is worth while. Too many problems, I gave up on that years ago personally
I would still love to get decent composite out of the Raspberry Pi though, for more casual games it's quite a bit more convenient to use and there's also a fair number of MAME cores that run fine on my Pi4 but I don't expect them to get a native MiSTer core anytime soon.
turns out the top the screen was good, but the bottom had some weird spots. I'm still messing with this but I think it's hard to avoid using the filtering
SNES and PSX look good in 240p and 480i with bilinear filtering on and a resolution in retroarch of 702x496 with a 12 x -8 offset. Interesting (to me)
I wish i had a way to test input latency differences in the audio and video between the Raspberry Pi and the real hardware. It feels better than most emulator setups but not as good as the real thing. I'd guess 5-10ms of latency in the video
i used some files someone was ever so nice to make, and it gives all emulators 240p and the menus run in 480i. been running it for years. it WILL run things like Quake in 240p, even non-core emulators and games (OpenTyrian will run like this). i got a video on my channel detailing it
Any updates to true 240p and settings to adjust? I have Pi 3B and Pi 4
I don't even have that stuff anymore so I do not have any updates. I miss the ol crt
Thanks for the info. Just curious. Are you using a Pi3 or Pi4 here?
It is a Pi 3+ I'm pretty sure, definitely not the 4
it's a 3 model B+, the Pi4 circuit around the AV out looks much more robust, I wonder if it has lower latency, less reliance on software. I'm glad it's still there.
@@OGmolton1 The best thing to me about the Pi4 is USB3. The composite video is disabled by default but can be enabled. I have yet to try it out.
the way i used to do it with retropie I think i would the tv video mode to 960p then do a 4x integer scale ,, i think it was 1024x960 or x5 wide 1280x960 but with integer scale on.. should fill the screen .. should be in the run command when you launch the game.. not sure how to do it in recalbox tho
I never thought about trying to upscale the actual screen resolution more, i thought that would ake it 480i again. I'll have to look into that
@@OGmolton1 It works ,, the pi will output 720x240 no matter what when the config is set for 240p,, but its like upscaling the internal resolution.. if you use retropie you can set ES to 480i but run the games @240p .. but I'm not to sure about recalbox or batocera linux ..
im using virtualman's retro bliss image file. What button did you press to get into that menu screen??
select was the hotkey enable button on this setup, that plus X or playstation triangle brought the retroarch menu up
@@OGmolton1 thanks.
so basically the '240p' that retropie generates is a 480i ? i also have my composite rpi with the sdtv_mode=16 and framebuffer to 320x240, the output is always shown as 640x480 on retroarch..
but i found someone on reddit and youtube, they're able to get progressive 320x240 on their retroarch custom_viewport.
have no idea how to achieve that, because at 480i, the scanlines is not showing at all.
there's multiple ways to do it, but the changing the setiing to "NTSC 4:3 P" manually that i talk about in the video and link an article about in the description is the best way to get true 240p from the pi because it will switch back to 480i in the menus and for other emulators that don't use the 240p modes. yes, it uses 240p if you have it set right. the retroarch rendering resolutions might still be higher but the pi is rendering a 240p image... hmm, i should have messed with those internal resolutions a bit too, but it can be saying 640x480 in retroarch and still be showing a 240p image I'm pretty sure
@@OGmolton1 oh my i missed that ntsc 4:3 p" part. okay thanks will try it out!
It is not only about 240p but also about horizontal resolution. If the Pie is locked to only a certain resolution on the composite output then obviously game over with pixel perfect output matching the original NES...
I gave up on composite on Pi3 and Pi4. RetroPie, Lakka, Batocera and ReclBox are all garbage when it comes to composite support. The Wii is the best native way to emulate 8 and 16 bit consoles.
yeah, quite a delay, that was something I didn't really notice till after this video, golf games made it very clear there was a delay issue. quite disappointing, thats the biggest plus of a true composite output of an old analog video device
Снято конечно пиздец. Пьяный что ли был?