Spent the last couple of hours with the new IVTC feature, here is what I found:
First of all I could not find any hard telecined sample clips for download, so I made some myself...
Quote:
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How can you tell if a 29.97 source is truely interlaced, or if it is hard telecined?
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The answer is simple, A2D does not make any attempt to detect hard pulldown automatically. The IVTC checkbox becomes active whenever the source has a frame rate of 29.97 fps and is flagged as interlaced.
So it is the responsibility of the user to make sure that the source is really hard telecined before using the IVTC option. I am not aware of any automatic method for this, which means that the user must step through the source frame by frame and make sure that there is a constant 3:2 pulldown pattern. Using IVTC on truly interlaced content will lead to catastrophic results.
I noticed that when a standard conversion to PAL is done at the same time, the fps change behavior is not consistent. Right now A2D always uses a hard fps change command (like ChangeFPS) to bring up the rate to 25 fps. IMO it should behave like it does for a 23.976 progressive source file, and this is use either PAL speedup (if the checkbox is ticked) or use DGPullown.
Cheers
manolito