Thread: HD to DVD
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Old 17th November 2012, 21:18   #10  |  Link
TheSkiller
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Join Date: Dec 2007
Location: Germany
Posts: 632
Quote:
Originally Posted by srfscenar View Post
OK, the best way I know to convert the 23.98 --> 25, is to use Cinematools for converting the Video and Audio streams
and then take the audio and correct the pitch with ProTools, right?

Is there a better way?
Probably yes (and faster).
I don't know Cinematools, but to be honest since 23.976 -> 25 via Speed-up is a two-liner Avisynth script (excluding audio), I'd just do it using AviSynth. There's one huge advantage: you can be sure it does exactly what you tell it to. Also, while you're at it, that's where you could do the scaling to DVD frame size.

There are some quirks and tricks concerning the scaling. Scaling from HD to SD is surprisingly a rather complex process actually.
Well, it all depends on how much effort you want to put into it, since there are no "best" settings but consider the following to be most likely quite a bit superior compared to what most NLEs would spit out.


Code:
SourceFilter("1080p23.976 Source") #depends on source
AssumeFPS(25) #Speed-Up to 25 fps


#scaling, here is a suggestion specifically for HD to SD

Sharpen(0.5, 0) #pre-sharpen horizontally to better keep hor. details
BlackmanResize(704, 576, taps=4)
Blur(0, 0.6).Sharpen(0, 0.4) #mild vertical low-pass
The result of that script would either be saved to a lossless intermediate or you can feed it directly to CCE.
704x576 is a valid DVD frame size by the way, without going into further detail, it's a good thing to use.


The only thing that is a bit troubling in the Speed-Up process is the audio. Video stays unchanged, the frames are just played back faster.
A pitch-corrected conversion style would be desireable.

Basically, you need to strip the original audio from the video file and use some audio editor to apply Speed-Up. Almost every audio editor has a preset for that.
After that the audio needs to be encoded to a DVD compatible audio format (MP2, AC3 or WAV, at 48 kHz) and can then be used together with the CCE encoded MPEG2 video to author a DVD.


Quote:
Originally Posted by srfscenar View Post
PS: If we take the 25p, it will come directly from a MAJOR studio from US. I think I will trust them to do the conversion!
Right, one would think so. And I hope that's the case.
But let me just mention this: quite many times I have seen videos here on PAL TV, say major music videos for example, which originated from 23.976 fps, converted in a truly awful way where one frame each second was simply shown twice (result: ugly stutter every second). Everything is possible nowadays...

Last edited by TheSkiller; 17th November 2012 at 21:26.
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