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jmac698 · 3rd March 2006, 05:30

Have we been talking about different things all this time? When I said my resolution was 3.75MHz I meant the chroma part only. the luma part is 6MHz, and therefore, my C4All technique has chroma also at 6MHz.
The smearing I now believe is an inherent function of svideo, because the chroma information is lowpass filtered relative to the luma.

I posted some new tests, which show this smearing. You can't read the colored text in svideo, but you can in component.

But what is really going on here is quite complicated;
1) The chroma offset of YV12 sampling adds 1 pixel of blurriness around a color boundary,
2) The DVD player is upsampling the YV12 chroma with bicubic or higher order interpolation,
3) Svideo itself is filtering the resulting chroma

To really know my final chroma resolution measurement I think I need a controlled source like a video card output, with no chroma upsampling.
Anyhow, I'm quite convinced by now it gives at least 2x better quality. Aren't you?
To finish this off, I only have to workout the calibration issues, that are giving that stupid color cast.

3rd March 2006, 05:30	#21 \| Link
jmac698 Registered User Join Date: Jan 2006 Posts: 1,867	resolution in luma vs chroma Have we been talking about different things all this time? When I said my resolution was 3.75MHz I meant the chroma part only. the luma part is 6MHz, and therefore, my C4All technique has chroma also at 6MHz. The smearing I now believe is an inherent function of svideo, because the chroma information is lowpass filtered relative to the luma. I posted some new tests, which show this smearing. You can't read the colored text in svideo, but you can in component. But what is really going on here is quite complicated; 1) The chroma offset of YV12 sampling adds 1 pixel of blurriness around a color boundary, 2) The DVD player is upsampling the YV12 chroma with bicubic or higher order interpolation, 3) Svideo itself is filtering the resulting chroma To really know my final chroma resolution measurement I think I need a controlled source like a video card output, with no chroma upsampling. Anyhow, I'm quite convinced by now it gives at least 2x better quality. Aren't you? To finish this off, I only have to workout the calibration issues, that are giving that stupid color cast.