How to determine origin of NTSC video ?

[ppera2]

In case that it is correctly telecined, it's easy - check Force Film in DVD2AVI ...
But how to know is it true NTSC (TV record) or PAL converted to NTSC by added fields/frames. Problem is that it is usually always interlaced, and I don't see easy way to check it by lookong frames.

Or should I make test with some script, like this:

Telecide()
Decimate(cycle=6)

If it gives smooth video, then it is converted PAL ???

[hakko504]

Test interlace by using this simple test script#ComplimentParity()
SeparateFields()If all ghosting/interlacing effects are gone then it is native NTSC (or PAL if you started with a 25fps video). If it seems like movement goes back and forth then you probably have a PAL stream converted to NTSC that can be corrected back to PAL by using your sample script (also try turning on ComplimentParity()). And lastly if you still see ghosting/blending effects then I recommend that you use a lot of noise filtering and maybe combine that with Decimate(6). In this case you will have to do some experimenting until you find the best settings. I ended up with a situation like this when I did Texas Chainsaw Massacre last week. The swedish version of this PAL DVD was awfully converted from the NTSC DVD so I used Telecide() followed by smartsmoother() and temporalsmoother() to get the best result (at reasonable speed)