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Old 27th February 2006, 03:58   #1  |  Link
jmac698
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Join Date: Jan 2006
Posts: 1,867
New Technique: Component4All!!

Yet another ground-breaking cap technique: now anyone can capture pure component video with no special equipment! Forget expensive pro-level cards, you don't need 'em!

Updated 03-2006:
This technique increases your potential resolution by about 2x beyond what you could do with lossless HuffyUV. So the real resolution is 1440x480, yes that's high-def! To keep this amazing resolution you will have to save in hi-def, otherwise, you will lose - for example saving as Huffyuv will use YUY2 color format - this means 2 pixels of color are stored as one.

Caveats:
- your source must be 4:4:4 ** UPDATE: this technique always improves quality, because svideo has inherently low color resolution, even if your source was only YUY2 orignally. You can get all the 4:4:4 quality as well if the source uses real chroma or 4:4:4 chroma upsampling.
- you will have to cap 3 times in a row, in a repeatable way
- it's slow
- the cheap and fast version, has slightly wrong colors
- you have to really want some hi-def glory...

Ok, now here's how: you need a "Y" splitter cable, two females to one male, type cinch/RCA/phono. You need an svideo to composite connector, or just a composite connector on your cap-card.

DISCLAIMER: This technique requires you to make non-standard connections. The risk is your own.

Connect Y directly to your composite in. Cap. Connect Y and Pb together, send to your composite in. Cap. Connect Y and Pr together. Cap.

Make 3 files: y.avs, ypb.avs, ypr.avs. Put your mpeg2source and trim commands in here, so that all files start playing from the same frame.

Final step: run this script.
Code:
y=avisource("C:\MyVideos\y.avs")
ypb=avisource("C:\MyVideos\ypb.avs")
ypr=avisource("C:\MyVideos\ypr.avs")
vyu=mergergb(ypr,y,ypb)
return(vyu)
That's it! Your done. The final file is in full resolution RGB. Resize and convert to YUY2 as needed.

Results:
-The grey range, and flesh colors are excellent. Some rare colors are shifted, but you cannot notice this. In theory it's "wrong", but it works.
-The color fringes around strong colors are gone! (something I find very annoying about s-video).
-If you dropped any frames in any caps, you will start to see some ugly color ghosting.
- UPDATE: I now have a script which exactly recreates the RGB picture, colorbar test patterns are accurate. However this requires some careful, one-time calibration. I'm working on the calibration proceedure.
- UPDATE: I have test results which prove >=1.6 color resolution as measured from a DVD Video Essentials test DVD pattern - chroma frequency sweep.

I have many more ideas brewing - stay tuned. (>2 times further resolution is possible...)

Last edited by jmac698; 7th March 2006 at 22:19. Reason: disclaimer
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