Audio Editing

[MattKern]

Hi Folks

I have been programming for about 5 years but have never done anything like this so I will run this by you to get some feedback.

Hopefully I can use wavs for this entire process.

I need to take x number of audio files (speech), concatenate them, mix them with another audio track (music) and then possibly trim (fade) the resulting file and server it up as an mp3 and/or wav.

Here is where I am currently:

Get the initial array of filenames, concatenate the corresponding wavs with proper spacing and get the total file length for the new single file: This I can do
Mix the new speech file with a second music bed file: I can't figure out how to do this
Fade the music out on the resulting track after the speech has finished talking: This I can do.
Serve up the final mixed wav as a file after fading: This I can do.
Convert the final mix to mp3 to serve it up as a file: I can't figure out how to do this

Any help would be appreciated.

Thanks

Matt

[Dave Benton]

Presumably you're not trying to do the mixing on the server!

If you're running windows I'd suggest downloading "Audacity" and the LAME MP3 codec. (Both are free)
Run audacity opening your first sound file (probably the one that you're going to place everything in time against).
Then in the "project" menu "import audio" which will add a new track, you can then fill up this track with blank space to that the sounds on it are placed where you want them. Repeat this process as necessary. Audacity will let you adjust the levels, left/right placing (pan) and can do the fade in and outs as well.
When you go to save this (as an MP3 or wav) audacity will create the mix for you.

Audacity is not the most sophisticated multitrack audio program around, but it works and with patience and experimentation it can do an awful lot.