_,,,^..^,,,_ said:
Interesting... so, I pass the LD video out to a DVD recorder in, then DVD recorder out to the video capture card in, I have the first capture; then I switch off everything, do a second capture, average the two and obtain a chroma noise free result, right?
Correct, but only if the second capture has a 180° phase difference from the first. It sometimes takes several captures before you get one.
Also, it's binary. A capture either has a 180° phase difference from the previous one or it doesn't; there's no in-between. You'll never have a 57° phase difference, for instance.
It's always either 0° (no cancellation) or 180° (perfect cancellation).
_,,,^..^,,,_ said:
How could I check the second capture has inverted phase? I mean, with a test disc it's quite obvious, but with real moving pictures?
The easiest way is to look to see if the chroma noise (rainbowing) has been canceled-out. If it's canceled-out in one place, then it's canceled-out everywhere else.
This is particularly easy with Star Wars since C-3PO and the spaceship models rainbow like crazy.