Problem with pitch-compensation for sped up vids

Last I used shotcut was around september of 2020.
It was fine, pitch compensation sort of worked.

I now try to edit a video, speed a clip by 1.2, pitch compensation makes everything sound like it’s doubled, while cutting off all of the high end frequencies and demolishing percussive peaks. A flat, washed out echoing sound.

Anything happen to that function over the past couple of months?
Kind of sad given I rely completely on this function for the kind of videos I do.

What version did you use previously?
What version are you using now?

The previous download I have is called “shotcut-win64-200711”

The latest, the one I’m now using is called “shotcut-win64-210227”

It sounds the same to me at 1.2x between those two versions on Windows. If the difference is subtle I may not be able to hear it.

There was a change in November to improve memory usage that would sometimes cause crashing and lipsync problems. That change turned off a processing feature to perform extended processing on transients. When I perform listening tests between the two versions, I can hear a slight degradation for voice-only audio.

I will add this to my todo list to revisit.

The latest release before that change is here:

If you try this version, please report back if you perceive that the sound is improved in that version.

I remember that. It was not just a small memory optimization. There could be a very large amount of memory used “for high factors of pitch shifting.”

Correct. Perhaps we can enable the transient smoothing for low factors of pitch shifting. But trial-and-error will be required to find the sweet spot.

I used it on gameplay clips captured from OBS. I will post here the sounds for comparison in a few hours when I get home.

I reverted the fix for the memory problem and the sound is the same for me. Perhaps that is not the problem and the timing is a coincidence. I notice that we always build against rubberband master. Maybe something changed in the library. More investigation required.

Just making sure to say I don’t remember it being this way previously.

The Windows build is using rubberband from msys2, since msys2 is a very current rolling distribution. In that build it is using rubberband version 1.9.0. That is its latest release from September. I have not found anything relevant in their issues - both open or closed.

For the sake of comparison, this is the same soundbyte, except I sped it up by 120% on Protools, a sound editing program.

This is exactly how I remember sped-up sounds sounding like in the previous version of shotcut I worked with and to which I am reverting

Last thing:

Reverted to “shotcut-win64-200711”

Fixed it entirely, though, to be fair, the quality of sped-up-sound is nowhere near the quality you get with protools lol :stuck_out_tongue:
Well, fair is fair, that’s a professional sound/music editing program that costs a fortune

Can confirm this bug exists also in version 201128

After some more listening tests, I am convinced that the November change caused the regression you are reporting. I have made a change to restore the previous method for smaller pitch shifts and to use the newer method for large pitch shifts to avoid the crashing problems. This change should be in the next release.

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I am ecstatic to have, in my small way, helped improve the quality of this one-of-a-kind, amazing product.

To clarify, the “smaller pitch shifts” means 0.5 - 2.0.

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