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25fps to 24fps software that fixes pitch shift
#1
Hey guys,

I'm looking for a soft, mac or PC (preferably mac) that fixes Pal audio pitch shift.

I've found some that fixes the speed, but the pitch remains the same (if higher pitch than the original).

Thanks if anyone can help.
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#2
You could do in Avisynth too, but lately I'm using Eac3TO - sorry, but they are PC only AFAIK
Fundamental collection thread site | Vimeo channel | My personal blog
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#3
For stuff like this I use Audacity. It's free and it works great. Here you have to options to fix audio from 25fps to 24fps (or 23.976fps)...

If the pitch is not an issue, you can slow down the audio using the "Change Tempo" option found in the "Effects" menu or if pitch is an issue, you can use "Change Speed" option found in the "Effects" menu which will alter the pitch and the speed for you.

In case you are wondering, the proper percentage to change PAL back to NTSC (25fps to 23.976fps) is -4.096%
If you are changing NTSC to PAL, the percentage is +4.271

If you are wondering about the math behind it, or anything else considering this issue, there is a thread that explains it all very well here: http://forum.videohelp.com/threads/30987...tch-change


Hope this helps and if not, feel free to ask more questions or PM meWink
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#4
Wow I had no idea Audacity did this. Thanks!
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#5
Happy to helpWink
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#6
Thanks. Once I have pitched and speeded the audio back to 23.976, I guess I can export to 5.1 (hopefully Audacity doesn't switch channels order if I imported from a 5.1 ac3 audio) ac3 without any loss (I will encoded with a superior bitrate to the original to ensure no loss)
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#7
Audacity doesn't switch channel order, as long as you don't want to...

Advice: of course importing a lossy file (AC3, DTS) will be, well... lossy? Wink so it's futile to use an higher bitrate than the input file... when I do a frame rate conversion, the bitrate of the converted file is always the same as the bitrate of the source one.
Fundamental collection thread site | Vimeo channel | My personal blog
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#8
I thought when making edits, working with a high quality up sampled source will almost always yield a higher quality result, all else being equal (due to rounding and other artifacts introduced by the editing algorithms themselves). Especially when you are talking about stretching/compressing time and/or pitch as in this case.

I'm not going to argue if these are perceptible or not (to some maybe), but probably not to my old ears though.
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#9
Hi guys, I'm running into a weird problem: I'm working on syncing a trailer to put on you tube, but my source, from which I want to the audio, is 23.976 even though it's clearly running at Pal speed. It's shorter.

I want to take that audio and sync it to the actual HD trailer which is running at 23.976 too (and is at correct speed) and is longer.

I know thanks to you how to convert the audio, but how do I convert the pal video running at 23.976 to 23.976 again to check the sync? FCPX just view it as 23.976 and doesn't adjust.

How is it possible to convert pal to 23.976 without changing the Pal lenght in the first place?
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#10
It sounds like the PAL speed footage has been incorrectly converted. Check for dropped frames/frame blending
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