Shrinking audio file on iOS

[Frantisekj]

Hello,

Could someone advice me if there is any way/app to shrink audio file/track on iOS. What I mean? Make audio file few seconds longer or shorter without changing content. Trying to overdub short videos with audio track made from subtitles. But it usually does not fit to video length.
iMovie can adjust length but it cuts content.

I tried several apps but they can change pitch or speed but haven't managed to change length. Or I am not skilled enough to do that.

Thanks a lot.

 

[BrianBaughn]

To shorten an audio file without cutting anything from it you'd have to change the pitch AND speed or, at a minimum, the speed…speed here meaning tempo of the playback.

Your description of what you're doing is a bit vague. Perhaps some clarification would prompt some possible solutions.

 

[Frantisekj]

To shorten an audio file without cutting anything from it you'd have to change the pitch AND speed or, at a minimum, the speed…speed here meaning tempo of the playback.

Your description of what you're doing is a bit vague. Perhaps some clarification would prompt some possible solutions.

Thanks for info. I guessed I described it well

As I said. Trying to overdub short videos with audio track made from subtitles. So i get transcription in form of srt subtitles and the using app that makes audio track from it with "propper" timing. But in ma language audio track is usually longer like video is 58 sec but audio 60.

 

[arw]

I understand the confusion regarding the title because shrinking normally refers to a decrease in (file-) size.

In your special case, you have the (probably easiest) option to stretch/shift the subtitle file accordingly and then re-generate your audio (not for iOS).
https://github.com/antoniocoratelli/srt-transform Shift and stretch a '.srt' subtitle file using a linear transform.

If you already achieved to change the speed of the audio, then the result must be longer or shorter accordingly. Otherwise it would have been a pitch correction.

But from my experience, it's generally easier to adjust the framerate of the video to match the speed/length of the audio track (losslessly). This way the pitch level of voices stays untouched (although this probably doesn't matter in your case).
Usually it's just a switch between 24p, 24fps, 25fps or 30fps.

I do not know any solution for iOS but the new Final Cut for iPadOS should be able to - although probably not losslessly.

 

[Frantisekj]

Thanks guys. I now understand what I need and realized I have apps that can do what I need. I just have not discovered potential or haven not seen it. Now I can do synthetic dubbing in minutes sometimes 👍