Quote:
Originally Posted by Anime Viewer
Another thing I noticed about NNEDI3 when used for chroma upscaling is that it can have a big hit to rendering speed even when it shouldn't be doing much (like if your playing a 1920x1080 video on a 1920x1080 screen.
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Actually chroma upscaling should be doing exactly the same work when playing a 1920x1080 video on a 1920x1080 screen as it would with any other resolution screen.
The chroma is 1/2 the resolution of luma in both directions (4:2:0). You need to resize it to match the luma before converting to RGB. This means that chroma scaling is always used and is independent of the output resolution.
This idea seems to be hard for some:
There are three image planes for a color image. On a bluray the black and white information (luma, Y) is stored at 1920x1080. Color information is stored as two 960x540 images (chroma, U & V or Cb & Cr). One needs to resize the two 960x540 images to match the 1920x1080 luma before converting to RGB.
This resize happens before anything else madVR does and it almost always needs to be done (it is only not needed when watching a 4:4:4 or RGB video).