How to get an mp3 out of a camtasia screencast

I am using camtasia studio 2 to create my screencasts. This works really nice and quick with a powerpoint presentation. I use this setting to records my lectures and to prepare them for screencasting. But I also wanted to create a podcast out of the screencast. That is I had to get the audio separated and changed into an mp3 file.

It took me a little while to find a way. Here are the steps I took:

1. Open your project in camtasia
2. In the 'files' menu choose 'save audio as ...' - The shortcut is Ctrl+U.
3. This will create a .wav file.

It is too bad that camtasia studio does not offer mp3 as a possible format here, then we would be done. So I had to look for a converter to change the .wav format into the .mp3 format. Fortunately the free digital audio editor audacity can be downloaded at sourceforge. In order to save files in the mp3 format the LAME MP3 Encoder must also the downloaded and the file 'lame_enc.dll' must be placed somewhere on the harddisk. Audicity will ask later where to find this file. So now for the conversion:

1. Open the .wav file in audacity
2. In order to create small files (I am only recording speech) I set under 'edit' in 'preferences' in the tab 'file formats' the bit rate for the mp3 export setup to 16. This allowes my to store about 40 minutes of lecture in a 5 MB file. The quality for speech is still acceptable I think.
3. Choose in the 'file'-menu 'export as mp3...'. You will be asked to fill out some fields describing your file. After your done the .mp3 file will be created.
4. Done!

Thanks to the people making the audacity editor and the lame library available. Great tool.

Ulrich