> Storing un-decoded composite video can actually be smaller, at least before you try > doing lossless compression on it. The chroma is modulated and embedded in the upper > portion of the luma range, so you are effectively only storing the Y channel.
That's an excellent point. Of course, you've thought about this a lot more than I have. > That's what D2 (composite digital) decks used to do at the same sample rate as D1 42 > YUV, which is the standard we're using now. It's only half the size, but it won't > compress well with standard techniques, since it looks like black and white video > with tons of checkerboard dots all over it.
Very much so. I follow some boards where people restore old TVs, and high-end early 1950s black and white sets often had video bandwidth out to 4 MHz and beyond. You can actually see the chroma on these sets as a sort of "interference" (although now it's relatively easy to modify an RF modulator to pass luma but not chroma).
> This isn't totally 'raw' video, though. It's time-base corrected and doesn't contain > the colorburst at the start of scanlines. If it's handled well during capture, this > isn't a huge limitation.
Right. Might be interesting to get some short captures in this format and see if MG could actually make them work though
ETA: MG is *very* interested in getting some short test captures that are the timebase-corrected NTSC - if you can do that, PM me please
Edited by R. Belmont (06/08/11 02:31 PM)
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