Which is ideal for framerates close to 60 fps, e.g. the SNES.
Here is a picture with the original AR of 8:7 and a resolution of 1024 x 896 :
I read this too :
Now here comes the important part: People generally get wrong how to aspect correct the SNES. They think you take the 256×224 active area and stretch that to a 4:3 image. That's not how it works. Instead, a formula is devised based on the pixel clock rate. In the case of the NES, SNES, and Genesis's 256×224 mode, the formula is 256 * 8/7, which equals about 293×224 for proper aspect correction. When scaling, the most accurate approach is to scale first and then apply the formula. So 2x scale would be (256 * 2) * (8/7) = 585×448 and 3x scale would be (256 * 3) * (8/7) = 878×672 and so on. Of course it's better to use multiples of 2 when it comes to digital displays, so for 1x scale: 292×224, and 2x scale: 584×448.
At 5.37 MHz, exactly 280 pixels fit into 52.148 μs. The ColecoVision, Master System, NES, and Super NES fill 256 of these with picture and the rest with black or solid-color side borders that fit in the overscan part of the signal that a TV doesn't display. To stretch 280 pixels on 240 scanlines to a 4:3 frame requires stretching each pixel horizontally by a factor of 8/7, giving an 8:7 pixel aspect ratio. Vertically, the NES always produces 240 scanlines, and the Super NES is switchable between 224 and 239. But it's traditional to crop the image at 224 lines as a rough approximation of what a TV cuts off. Thus in 720p mode, the device scales the 256x224 pixels produced by the built-in emulator to about 256*8/7*3 = 878 pixels wide and by 224*3 = 672 pixels tall. Elsewhere, I've collected a list of dot clock rates for classic arcade, console, and home computer platforms' picture generators and their resulting pixel aspect ratios.
It's why I'm also not a fan of the "CRT shaders", even if I find that some are really great and impressive!
RGB 24 :
YV12 with the UtVideo codec :
I know, it's very blocky ! :-P I used the "Resize8" plugin because it uses a anti-ringing filter by default : http://avisynth.nl/index.php/Resize8 The ringing isn't always bad, because it adds sharpness, but I find that the result with the anti-ringing filter is quite good (but it can adds other defaults if the scaling factor is too big). I didn't use the true 4:3 aspect ratio, but : 256 * (8:7) = 2048/7 So : (2048:7)/224 = (64:7)/7 = 64:49 YV24 then YV12 with AVS script (like feos did) :Language: avisynthPointResize(2048, 1792) Resize8(2820, 2160, kernel="Spline36", kernel_c="Spline36")
We can notice different pinks, reds and greens ! But the result is good ! ;-) YV12 with the "UtVideo YUV420 BT.709 VCM" codec :Language: avisynthPointResize(2048, 1792) Resize8(2820, 2160, kernel="Spline36", kernel_c="Spline36") luma = ConvertToYV24(matrix="Rec709", chromaresample="point").ConvertToYV12(matrix="Rec709", chromaresample="point") chroma = ConvertToYV24(matrix="Rec709", chromaresample="point").ConvertToYV12(matrix="Rec709", chromaresample="point") MergeChroma(luma, chroma)
The conversion of the color space is most blurry and less clean than the conversion with the AVS script. Maybe bicubic or something else is used to reduce the chroma resolution. But in theory, the reduction of the chroma needs interpolation too, like when we upscale a picture, so "PointResize" or something else, it's a question of taste I suppose ;-)
However, the color matrix is good and the file is taggued with it :
General Complete name : H:\UtVideo.avi Format : AVI Format/Info : Audio Video Interleave File size : 229 MiB Duration : 2 s 567 ms Overall bit rate : 750 Mb/s Writing library : VirtualDub2 build 41585/release Video ID : 0 Format : YUV Codec ID : ULH0 Codec ID/Info : Ut Video Lossless Codec Codec ID/Hint : Ut Video Duration : 2 s 567 ms Bit rate : 749 Mb/s Width : 2 820 pixels Height : 2 160 pixels Display aspect ratio : 4:3 Frame rate : 60.000 FPS Color space : YUV Chroma subsampling : 4:2:0 Compression mode : Lossless Bits/(Pixel*Frame) : 2.048 Stream size : 229 MiB (100%) Audio ID : 1 Format : PCM Format settings, Endianness : Little Format settings, Sign : Signed Codec ID : 1 Duration : 2 s 567 ms Bit rate mode : Constant Bit rate : 1 024 kb/s Channel(s) : 2 channels Sampling rate : 32.0 kHz Bit depth : 16 bits Stream size : 321 KiB (0%) Alignment : Aligned on interleaves Interleave, duration : 21 ms (1.23 video frame) Interleave, preload duratio : 500 ms
Oki doki ! :-) For the Nnedi3, yes, I already tested it ! ;-) It gives excellent results, but gives sometimes some artefacts too :-/ But I like it too. What did you use to upscale to the final resolution ? Lanczos3 ? I forgot to say that personnally, I prefer the "Spline36" algorithm rather than "Lanczos3" (I did lots of comparisons to be sure). The result is quite similar, but there is a bit less ringing ! ;-) Later, I will show you other scripts that I tested, often softer that what I showed here (maximum pixels, very blocky ! :-P ), not crazy things, but some things that I find pleasant... but never perfect of course ! ^_^ It's too subjective !Language: avisynthPointResize(2048, 1792) Resize8(2820, 2160, kernel="Spline36", kernel_c="Spline36") luma = ConvertToYV24(chromaresample="point").ConvertToYV12(chromaresample="point") chroma = ConvertToYV24(chromaresample="point").ConvertToYV12(chromaresample="point") MergeChroma(luma, chroma)
(source : https://youtu.be/iPohK0D8qvM )
I know the picture is bad :-P
But what is interesting is that the guy used a VGA CRT monitor instead of a CRT TV with the real console and an OSSC.
I think it's better to compare with this than with a CRT TV and its scanlines, because it's closer to the conditions we have on a modern screen which hasn't scanlines.
But there is the version with a CRT TV too ^_^ :
(source : https://youtu.be/OxBXiCPFM78 )
And so, here is a test with (very basic) scanlines and a little boost of gamma to compensate :
Personnally, I wouldn't use scanlines for YouTube. It's just to compare ! :-) The same without scanlines :Language: avisynthPointResize(512, 448) Scanlines(STRENGTH=75) Levels(0, 1.25, 255, 0, 255) PointResize(1024, 896) BilinearResize(2820, 2160) # Personnally, with some other games like "Super Metroid", "Mr. Nutz" or "Super Mario World", I keep the 8:7 AR, so I choose a resolution of 2468 x 2160
Another capture for model :Language: avisynthPointResize(1024, 896) BilinearResize(2820, 2160) # Personnally, with some other games like "Super Metroid", "Mr. Nutz" or "Super Mario World", I keep the 8:7 AR, so I choose a resolution of 2468 x 2160
I tested something softer (without scanlines) :
I choose to change the aspect ratio with the bilinear filter to begin, because I think it's more convincing, but you can choose to do that only with the Spline36 resizer. The same picture without scanlines :Language: avisynthPointResize(512, 448) Scanlines(STRENGTH=75) Levels(0, 1.25, 255, 0, 255) BilinearResize(1170, 896) # Personnally, with some other games like "Super Metroid", "Mr. Nutz" or "Super Mario World", I keep the 8:7 AR, so I choose a resolution of 2468 x 2160 Resize8(2820, 2160, kernel="Spline36", kernel_c="Spline36") # Personnally, with some other games like "Super Metroid", "Mr. Nutz" or "Super Mario World", I keep the 8:7 AR, so I choose a resolution of 2468 x 2160
I tested so many other things (with Nnedi3 too ;-) ) that I can just say one thing : the simpliest is often the best. I know that lots of people hate the bilinear filter, but personnally, I think that the best result is this (from what I suggested of course) :Language: avisynthPointResize(512, 448) BilinearResize(1170, 896) # Personnally, with some other games like "Super Metroid", "Mr. Nutz" or "Super Mario World", I keep the 8:7 AR, so I choose a resolution of 2468 x 2160 Resize8(2820, 2160, kernel="Spline36", kernel_c="Spline36") # Personnally, with some other games like "Super Metroid", "Mr. Nutz" or "Super Mario World", I keep the 8:7 AR, so I choose a resolution of 2468 x 2160
There is no miracle with an upscale ! :-( Some people may think that it's to simple to be good, that it's inaccurate, but was it accurate in those days ? :-) The other problem, as I said above, it's the influence of the modern "pixel art" indie games and their pixel perfect blocky representation... :-P I'm curious to know what you think ! ;-) But I tested enough things (like a lunatic ^_^ ) to know that it's never finished if we are looking for the perfection ! The rest is too subjective... ! Personnally, I keep the PointResize filter with the bilinear. This with 1080p :Language: avisynthPointResize(1024, 896) BilinearResize(2820, 2160) # Personnally, with some other games like "Super Metroid", "Mr. Nutz" or "Super Mario World", I keep the 8:7 AR, so I choose a resolution of 2468 x 2160
This with 1440p :Language: avisynthPointResize(512, 448) BilinearResize(1410, 1080)
And this with 2160p :Language: avisynthPointResize(768, 672) BilinearResize(1880, 1440)
Voilà ! :-P Sorry, there is no big revelation ! :-/ Just some reflexions I think.Language: avisynthPointResize(1024, 896) BilinearResize(2820, 2160)
That's true, feos' script win ! :-P But the only strange thing I noticed is that the colors changed. We see this in the reds and greens. I don't knwo if it was itentional or not.
There is a slight color bleed which is intentional to make the pixel sizes consistent.Language: avisynthAVISource("movie.avi") PointResize(3408, 2928).LanczosResize(2880, 2160, taps=2) ConvertToYV24(matrix="Rec709", chromaresample="point") ConvertToYV12(matrix="Rec709", chromaresample="lanczos") # Notice the change in chromaresample
I use this codec because I had a problem of wrong color matrix when I used the Lagarith codec (because there is no tag for the color matrix) and then encode the video with Handbrake. I'm not a professional for encoding, it's why I use Handbrake. I think the result is really good ! :-)
For the Nnedi3, yes, I already tested it ! ;-) It gives excellent results, but gives sometimes some artefacts too :-/ But I like it too. What did you use to upscale to the final resolution ? Lanczos3 ?
I forgot to say that personnally, I prefer the "Spline36" algorithm rather than "Lanczos3" (I did lots of comparisons to be sure). The result is quite similar, but there is a bit less ringing ! ;-)
I thought the current script would be point resize to the target resolution or bigger in multiples of 2, then downscale to the target resolution if needed. For example:There is a slight color bleed which is intentional to make the pixel sizes consistent.Language: avisynthAVISource("movie.avi") PointResize(3408, 2928).LanczosResize(2880, 2160, taps=2) ConvertToYV24(matrix="Rec709", chromaresample="point") ConvertToYV12(matrix="Rec709", chromaresample="lanczos") # Notice the change in chromaresample
Yes, Lagarith YV12 is probably using Rec601 color matrix, but since you already know how to use Avisynth, why not capture in RGB and convert it yourself as a last step, then send to Handbrake?
What he did was upscale it above the target resolution, then downscaled to the target resolution with AreaResize. AreaResize uses weighted averages to figure out the end result.
This is why I personally use Lanczos with 2 taps instead of 3. Less ringing but more blurry.
So I tested this with a 240p image doubled to 480p. With a Super Nes game, I tested this :Language: AviSynthBlur(0, 1.0)
Language: AviSynthPointResize(512, 448) Blur(0, 1.0)
For me, it's only like this that I finally see a convincing relief in the image, like it was on a CRT.
But as everybody can see it, the result is blurry and not really nice ! Like a deinterlaced video with blended fields in fact ^_^
But I think that all the problem of the games in 240p is exactly the same that it is with interlaced contents on our modern screen.
It's a bit unnatural... :-/
It doesn't work without deinterlacing or something else and even with that, it's far from perfect.
For me, it's the only problem ! It really doesn't work on a modern screen ! Only the modern pixel art games are done to perfectly work on a modern screen I think.
With the old 2D games, we always have to use a trick to render them acceptable.
In the ideal, we should have the double of the definition for the vertical resolution !
But I think there is an idea like what I suggested, a kind of reversed deinterlacing (no interlacing of course) for the old progressive content made to work with scanlines.
In fact, I analysed what they did with the Super Nes games.
With the biggest scaling (the resolution is 1170 x 960), they :
- double the resolution to 512 x 480 (448 pxs + black borders)
- move the picture from 1 pixel horizontally (it's like a ghost image, it doesn't work with a simple blur)
- double the resolution and correct the aspect ratio with a bilinear filter to achieve the resolution of 1170 x 960
It's really smart and work quite well ! :-)
But lots of people will find the picture too blurry. But the effect in motion is good and rather natural I think !
I found it here and just cut the borders :
http://www.nintendolife.com/news/2017/09/hardware_review_the_snes_classic_mini_is_the_perfect_link_to_the_past
There are others here :
https://www.eurogamer.net/articles/digitalfoundry-2017-nintendo-classic-mini-super-nes-system-review
The resolution is "877 x 672".
It's just a Simple X3 (or nearest neighbor) and a bilinear filter to correct the AR.
And just to check :
672 x (64:49) = 877
So even the "official" Super Nes Classic Mini doesn't use an exact 4:3 aspect ratio ;-)
=> List of the aspect ratios
