Hi Paul,
I can give you the answer to question 2 directly. They are the same for both the camera module and the signal generator. With a NTSC source we get the following values:
0x52: 0x00
0x56: 0x00
0x59: 0x02
0x50: 0xC2
Which seems correct for a NTSC source. And we get the same values when it's not working (camera module) and when it's working (signal generator).
For question 1, what part of the video signal are you interested in (so we can do relevant captures)? Color burst, sync signals?! Which comes back to the original question, which part of the video signal is of interest for automatic detection of YC.
/BR Johan