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manolito · 17th February 2020, 23:33

Yes, this method does cause a slight judder, this is how ChangeFPS works. But the Merge() command makes this judder much less obvious (at the cost of introducing a little blending) than just using a simple ChangeFPS(25) on the 23.976 source clip.

Make a short test conversion and compare the results once using your above script and then only using ChangeFPS(25).

If you cannot live with this judder then you need to use classical PAL speedup which involves speeding up the audio, too.

More thoughts:
Is your source really pure 23.976 progressive, or does it have soft pulldown?

And yet another method you could try is to use frame rate interpolation instead of ChangeFPS. A2D comes with the (renamed) jm_fps function. To use it you need to import the MCJMFPS.avsi from the AVStoDVD\Lib folder at the top of your script and then use MCJMFPS(25) to change the frame rate. The result will not have judder and audio can be left alone. But depending on the source characteristics you could end up with some artifacts (mainly warped vertical lines). And it does not work well on anime.

17th February 2020, 23:33	#3315 \| Link
manolito Registered User Join Date: Sep 2003 Location: Berlin, Germany Posts: 3,079	Yes, this method does cause a slight judder, this is how ChangeFPS works. But the Merge() command makes this judder much less obvious (at the cost of introducing a little blending) than just using a simple ChangeFPS(25) on the 23.976 source clip. Make a short test conversion and compare the results once using your above script and then only using ChangeFPS(25). If you cannot live with this judder then you need to use classical PAL speedup which involves speeding up the audio, too. More thoughts: Is your source really pure 23.976 progressive, or does it have soft pulldown? And yet another method you could try is to use frame rate interpolation instead of ChangeFPS. A2D comes with the (renamed) jm_fps function. To use it you need to import the MCJMFPS.avsi from the AVStoDVD\Lib folder at the top of your script and then use MCJMFPS(25) to change the frame rate. The result will not have judder and audio can be left alone. But depending on the source characteristics you could end up with some artifacts (mainly warped vertical lines). And it does not work well on anime. Last edited by manolito; 17th February 2020 at 23:49.