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Old 4th February 2018, 16:35   #13  |  Link
manolito
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Join Date: Sep 2003
Location: Berlin, Germany
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Yes, these explanations are all right on the money...

ConvertToYV12() is always inserted by AVStoDVD, because for DVD target the video has to be YV12, and if the source already is YV12 then this instruction is a NOP and won't hurt.

The audio delay value is automatically taken from the MediaInfo output for the source, it can be disabled in the settings. For some source formats this is a bit of a problem, though. Sometimes MediaInfo reports an audio delay of several seconds, and in my experience such huge audio delays have to be ignored.

The last line in the script takes care of the video and audio slowdown. "ResampleAudio" is only used when "SSRC" is not possible. It works reliably, but you need to know that it does not do any pitch correction (so the slowdown goes along with a lower pitch). If you need pitch correction you have to remove "sync_audio=true" and "ResampleAudio" or "SSRC" from this line and instead use the "TimeStretch(tempo={percentage})" command for audio slowdown.

This can also be a little problematic. Pitch correction is complex and prone to audible artifacts (unless you use expensive pro software). The TimeStretch plugin which is part of AviSynth 2.60 is old and does not support 6-ch audio. You can use a newer TimeStretch library by either using the separate TimeStretch plugin by Wilbert, or you can use AviSynth 2.61 Alpha.


Cheers
manolito

Last edited by manolito; 5th February 2018 at 16:54.
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