Extract Audio From Video - Manipulating - Reapplying 2 Video

Windows 10 - Version Audacity 2.1.2 - .exe Installer

Former Pro Tools User. Having no issue with converting YouTube Video of Church Service to MP3, importing to Audacity, applying affects, exporting back out.

The issue is I can only produce an MP3 of the Music for Praise Team Members. I’d like to find a way to export just the audio portion of the YouTube video of the service (converted to whatever it needs to be converted to…perhaps MP4?) , manipulate the audio of the entire service, then apply that audio back to the MP4.

Unless I’m missing something, it does not appear that Audacity has the capability to edit the audio of an MP4.

Even though that seems to be true, it seems there may be a way to get just the audio files of a video, use Audacity to spice the audio up and then reapply the improved audio to the video.

Any ideas?


Some background information first:

  • Audacity cannot import video and cannot do anything with video. Audacity is an “audio” application.

  • Audacity does not operate directly on files.
    When a file is “Imported” (including using the “File > Open” command), Audacity copies audio data from the file and works with the copied data. Audacity does not operate on the original file.

  • There are two broad categories for audio file formats: “lossless” and “lossy”.
    When audio data is written to a file in a “lossless” format (such as WAV, AIFF or FLAC), then the audio data in the new file is virtually unchanged. So when exporting from Audacity to a WAV format, the WAV file will be virtually identical to the audio data in Audacity.
    When audio data is written to a file in a “lossy” format (such and MP3, OGG, AAC or AC3), the audio data is “compressed” so as to make the file smaller, but there is a cost that some of the audio data is discarded and some audio quality is lost.
    ** When working with audio, the audio data should be kept in a “lossless” format as far as possible so as to avoid deterioration of the sound quality.

  • Audacity supports a limited number of audio formats (including WAV, AIFF, MP3 (import only), OGG and FLAC).

  • Audacity is able to use suitable versions of FFMpeg to read many other file formats, including reading the audio data from many video file formats.
    (See here for how to install FFMpeg: http://manual.audacityteam.org/man/faq_installation_and_plug_ins.html#ffdown)

It would be better to download the video (plug-ins are available for Firefox for downloading from YouTube), the import the audio into Audacity directly from the video file. This requires that you have FFMpeg installed. The advantage is that doing it this way, you avoid losing sound quality through the intermediate conversion to MP3.

If you have a suitable version of FFMpeg installed, then Audacity can import “the audio data” from an MP4 file.

To put the “spiced up audio” back into a video, you need to use a video program (such as Windows Movie Maker or Avidemux).

So your ideal workflow would be:

  1. Download the video
  2. Import the audio from the video file into Audacity (requires FFMpeg).
  3. Edit and process the audio as required in Audacity
  4. Export the audio from Audacity to a WAV file (lossless audio format).
  5. Use a video editing app to replace the original audio in the downloaded video file with the new audio from Audacity.


Not only an answer, but a breakdown of each part of the question & then a summation workflow.

Thank you isn’t a big enough set of words to express my gratitude.


Audacity+Avidemux tutorial here … https://www.youtube.com/watch?v=xS1zl_SMRbk