Editing audio portion of video

[edong]

The following are steps I am doing mainly for the purpose of increasing the volume, bass and treble of video files:

1. Record to MP3 the audio part. Then using Audacity, amplify and increase bass and treble. Then export as MP3 again.
2. Using a video editor, I mute the original audio, add the adjusted music, then render.

Is there a step whereby I can avoid rendering? I read something about demux/remux. Will it be faster and work in my case? It's mostly avi and MP4 files. Thanks.

[jagabo]

Get the ffmpeg source plugin for Audacity. Then you can import audio directly from your source files.

Use a muxer like VirtualDub (Video -> Direct Stream Copy mode, Audio -> Audio From Another File) or Mp4Muxer to mux your new audio with the original video.

[edong]

Thanks, Jagabo. I'll try that. (I hope you were not affected by the recent brush fire.)

[edong]

The ffmpeg worked but virtual dub and mp4muxer cannot open my file.

[jagabo]

If I remember correctly, MP4Muxer can only mux elementary streams. You need to demux the AVC video from the MP4 file (you can use MP4Muxer's demux tool for that) them mux the AVC elementary stream and your new audio stream.

[edong]

I finally opened the mp4 file. I add the newly edited audio then deleted the track of the old audio then I hit "multiplex." The resulting file only has audio and NO video. I'll try your new suggestion (if I can figure it out how), then post the result later. Thanks.

[jagabo]

To demultiplex the video stream: go to the Demultiplex tab in Mp4Muxer. Browse for the file you want to demultiplex. Highlight the video stream, browse to the output folder if you want it somewhere else, press the Demultiplex button.