Is there any way I can improve the audio quality of a file whose pitch I modified?

[CodingRox82]

I'm using the following commands to raise/lower the pitch of an audio file, but the problem is that the quality of the audio file seems kinda low after I use them. For comparison, I'm using the flutter_sound plugin to record and it has a simple pitch changing function that allows you to modify the pitch without saving the modified file to disk. The quality of this "temporarily modified" file sounds really good and by comparison the "permanently modified" file (created by ffmpegkit) doesn't sound so good. Could there maybe be something I'm missing in the commands I'm running? Or maybe is there a "polishing" command I can run after modifying the pitch?

await FFmpegKit.executeAsync('-i ' + MyAppFilesInProgressFileDir.path + currentMyAppFileFilename + ' -af asetrate=5000*1.5,aresample=5000,atempo=0.9 ' + MyAppFilesInProgressFileDir.path + currentMyAppFileFilename + 'High.mp3', ffmpegCallbackHigh);

await FFmpegKit.executeAsync('-i ' + MyAppFilesInProgressFileDir.path + currentMyAppFileFilename + ' -af asetrate=9250*0.8,aresample=9250,atempo=1.25 ' + MyAppFilesInProgressFileDir.path + currentMyAppFileFilename + 'Low.mp3', ffmpegCallbackLow);

[eric483]

The answer to this is no, You can not improve the sound of a file through ffmpeg.
Look at your file. 9250 and 5000 sample rates are awful.

A base method example of adjusting pitch is
ffmpeg -i 100h.mp3 -af asetrate=44100*0.9,aresample=44100 90h.mp3

The sample rates are 44100.
If you want better quality audio you need to start with a better quality sound file.

[CodingRox82]

@eric483 ah, sorry I'm very new to audio processing!

My app will run this on a variety of different phones. Do you know if there is a way to ensure that the quality of the user's input matches the quality of the output? Like maybe using code to determine the input sample rate of the user's recorded audio? Just spitballin' here, I have no clue about any of this stuff.

[CodingRox82]

@eric483 I tried your example and it increases the pitch but it speeds up the audio so much that you can't tell what the audio is saying anymore. How do I increase pitch while still maintaining the same duration?

[eric483]

you should go read the FFMPEG site.
it tells you what all the commands are and do for what you are trying to do.
The example I gave is ONLY to show you the difference in the quality of the recording.
Which was you're issue to begin with. As FFMPEG can't change the quality of what you put it, it can't "make it" better.
Everything else you are looking for is in the FFMPEG wiki.