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• How to change or modify pitch of audio file (music etc like .mp3 file)using FFMPEG ?

  18 octobre 2022, par syed kashifullah

  I want to change and modify pitch an .mp3 audio file using FFMPEG.
But I am unable to use FFMPEG to change or modify pitch of that sound.
what command (exact command) should be exactly use for changing pitch of an audio file ?

  


   String outPutPath = new File("/storage/emulated/0/Share it Application/Over_the_HorizonTemp.wav").getPath();
                 
                String[] strFfmpeg  = {"ffmpeg","-i" ,strInputPath,"-af", "rubberband=tempo=1.0:pitch=1.5:pitchq=quality" ,outPutPath};
                execffmpegBinary(strFfmpeg);


  


  execffmpegBinary Function :

  


  public void execffmpegBinary(String[] command) {
    Config.enableLogCallback(new LogCallback() {
        @Override
        public void apply(LogMessage message) {
            Log.e(Config.TAG, message.getText());
            Log.e("TAG", "apply: " +message.getText());
        }
    });
    Config.enableStatisticsCallback(new StatisticsCallback() {
        @Override
        public void apply(Statistics statistics) {

        }
    });

    long executionId = FFmpeg.executeAsync(command, new ExecuteCallback() {
        @Override
        public void apply(long executionId, int returnCode) {
            if (returnCode == RETURN_CODE_SUCCESS) {
                
                Log.e("1TAG", "apply:return code "+returnCode );
                Log.e("1TAG", "apply:execution Id "+executionId );
                Log.e("1TAG", "apply:execution Id "+ new FFmpegExecution(executionId,command));


            } else if (returnCode == RETURN_CODE_CANCEL) {
                Log.e("2TAG", "apply:return code "+returnCode );
                Log.e("2TAG", "apply:execution Id "+executionId );
                Log.e("2TAG", "apply:execution Id "+ new FFmpegExecution(executionId,command));

            } else {
                Log.e("3TAG", "apply: returnCode"+ returnCode);
                Log.e("3TAG", "apply:return code "+returnCode );
                Log.e("3TAG", "apply:execution Id "+executionId );
                Log.e("3TAG", "apply:execution Id "+ new FFmpegExecution(executionId,command));

            }
        }
    });
}


  


• ffmpeg : remove frames when audio mute

  23 septembre 2022, par dvt

  I have a video record of a public academic conference. For some reason, the audio is complete but intermittent(spectrogram sample). For each 5 10 secs, short mute interrupts, make me hard to focus on the content.
Thinking most of the video is static image, removing mute portion of the audio and corresponding frames might be a way to fix this.

  


  For now I've partially done using silenceremove and rubberband, stripping mute interruptions and stretch the audio to the same duration of the video. Steps below :

  


  


  1. Get the video duration with ffprobe
ffprobe -v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 sample.mp4

     


  


  2. Try silenceremove the audio once and Get its duration.

     


     ffmpeg -i "sample.mp4" -filter_complex "[a]silenceremove=stop_periods=-1:start_threshold=-50dB:stop_threshold=-50dB:detection=rms:window=0.01[a1]" -vn sample.wav
ffprobe -v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 sample.mp4


     


  


  3. Calculate the tempo manually (duration-audio/duration-video), for example I got 0.948.

     


  


  4. AIO command, rubberband added. Generate a fixed version from the source.

     


     ffmpeg -i "sample.mp4" -filter_complex "[a]silenceremove=stop_periods=-1:start_threshold=-50dB:stop_threshold=-50dB:detection=rms:window=0.01[a1];[a1]rubberband=tempo=0.948" -c:v copy -cutoff 7500 sample.fix.mp4

     


  


  


  I still wonder if there is a better way. Thanks guys.

  


  Refer :

  


  

  1. How to stretch the WAV file to the same video length ?

  


  2. How to trim out black frames with ffmpeg on windows ?

  


  


• Splitting an Audio File Into Equal-Lenght Segments Using FFmpeg

  29 avril 2021, par G-Power

  I want to split an audio file into several equal-length segments using FFmpeg. I want to specify the general segment duration (no overlap), and I want FFmpeg to render as many segments as it takes to go over the whole audio file (in other words, the number of segments to be rendered is unspecified).
Also, since I am not very experienced with FFmpeg (I only use it to make simple file conversions with few arguments), I would like a description of the code you should use to do this, rather than just a piece of code that I won't necessarily understand, if possible.
Thank you in advance.

  


  P.S. Here's the context for why I'm trying to do this :
I would like to sample a song into single-bar loops automatically, instead of having to chop them manually using a DAW. All I want to do is align the first beat of the song to the beat grid in my DAW, and then export that audio file and use it to generate one-bar loops in FFmpeg.

  


  In the future, I will try to do something like a batch command in which one can specify the tempo and key signature, and it will generate the loops using FFmpeg automatically (as long as the loop is aligned to the beat grid, as I've mentioned earlier).