Pitch Compensation adds an audio "pop" at the start of each clip

Bug
1

OS: Windows 10 21H1 19043.1586

Shotcut: 22.03.30 (but also happened with previous installation 21.10.31)

Repeatable: Yes

I created a project using Shotcut 21.10.31 and exported the final video to find that there was a single audio “pop” at the start of each clip where the audio is already loud and Pitch Compensation is selected. If I have a clip set to 1.5x speed that starts quiet and gets loud, I don’t hear a pop. But, if the clip is cut to start when the audio is already loud, an audio pop can be heard at the start of each clip. This happens over multiple clips in various parts of the project.

I thought it might be fixed in the newest version so I upgraded to 22.03.30. I used the same .mlt file created in 21.10.31 and got the same result. To rule out the .mlt, I created a new .mlt in 22.03.30, added 3 clips, cut them in similar spots, increased the speed to 4x for each clip, and then turned on Pitch Compensation for each clip but still got the same result. If I remove Pitch Compensation, there’s no popping. The pops can usually be heard when playing the video on the timeline, but not always. However, they can always be heard on the exported file.

Since Pitch Compensation seem to work perfect fine on clips that don’t start out loud, there might not really be a way to resolve this issue, it might just be a side-effect of the way I’m trying to use it.

I have 2 identical short clips (17MB each), one with Pitch Compensation and one without, if you’d like me to upload them. Thanks for your time.

-Mike

2

The poop occurred because the audio is no longer contiguous. The software does not know how to inspect audio before and after an event like this and do some automatic smoothing, and I doubt that will be added. The usual workaround is to make a 2 frame cross fade. If you use a video + audio transition there is an option in the properties of the transition to cut the video instead of cross dissolve.

3

Okay, thanks for your response, explanation, and workaround.

-Mike

4

Alternatively, if you use the Time Remap filter the audio pitch software does know the shape of the audio before and after a keyframe to make the audio contiguous. The problem is that splitting or separate clips creates this division and resulting incongruity.

5

I tried the suggested 2 frame cross-fade and then changed the Transition from Dissolve to Cut in Properties and the pops are gone, thanks!

-Mike

6

Is that really how “poop” occurs? :grin:

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