Mark,

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typically a sharper image with less filtering - although in that case it's more likely an argument for digital delivery vs analogue).

That is exactly my point. The idea of being down 3dB at Nyquist is for analog delivery. Now that we have a full digital pipeline, the old analog ways should no longer apply.

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But one can argue that correctly mastered DVD video should not have information above the Nyquist limit for the format anyway, so there shouldn't really be any benefit to breaking the rules.

They are not breaking any rules. A full amplitude Nyquist is not above Nyquist.

Three common algorithms to convert 4:2:0 to 4:2:2 include nearest neighbor, bilinear and bicubic. I have listed them in order of processing power, and quality, from lowest to highest. Most players today are using bilinear to convert (scale) 4:2:0 to 4:2:2. The algorithm to convert 4:2:0 to 4:2:2 is the same one used for converting 480p to 1080p because it is a scaling problem. To put anothe way, chroma on Blu-ray is 960x540. Bilinear will produce softer results than bicubic.

We wrote a paper on how to do better chroma upscaling a few years ago, but never published it. We shared it with some CE companies. Panasonic has that paper. We also provided them with a test disc to use. Our paper describes how to convert 4:2:2 to 4:2:0 for disc creation as well as the inverse for playback. Many Blu-ray movies have used our conversion from 10-bit 4:2:2 to 8-bit 4:2:0. Universal, Paramount, Disney, WHV and many others. If they are using our algorithm to convert back to 4:2:2 it`s a great thing.

Last edited by sspears; 2009-04-12 16:05.
Stacey Spears
Co-Creator, Spears & Munsil High Definition Benchmark, Blu-ray Edition and Lighthouses of the Pacific Northwest.