Lately I have been in the business of producing System Help in the form of screencasts
I have been using many of the suggestions outlined here, but until today I felt that I was really lacking a good tool to modify the audio of a screencast without messing with the video.
Some background for you, am one of the founders of a website called KeepUp and early on we really liked the idea of doing screencasts to help our users understand the system, we thought no one wants to read documentation, but watching a movie is easy.
My setup - MAC OSX Tiger on a mac book pro with 2 gigs of ram. Im using a external Samson Mic (CO1U), but the internal microphone worked pretty well also. To record the screencast I have been using a commercial tool called SnapZ Pro which allows you to record anything on your screen and do the audio at the same time. The only issue I have with SnapZ is that doing a demo and talking at the same time for me is a bit like rubbing my head and patting my tummy, I am just not that coordinated. Also if I messed up just one thing, I had to rerecord the entire script. I also wanted to try some other voices to see how people like them over mine.
First I tried IMovie HD which comes with ILife, and it does a great job at letting you edit the sound track and re-recording the sound, however, it imports the video into its own format which causes the video to lose lots of quality. When you record a screencast it is from your computers hi res monitor which is much more detailed than a video recorder (even high dev) for which Imovie is made for.
The answer came (surprisingly for me) in the form of quicktime pro. Quictime pro is fairly inexpensive about $30 USD. I had previously purchased it to encode some video from quicktime into other formats.
Anyway its not very straight forward how to use, so I will give directions here:
- load the movie in quicktime
- Click window/show movie properties, you will see at least 2 tracks (audio and video)
- Remove the audio track by unchecking it and hitting the delete button.
- Click file new audio recording, when you are ready, hit the red audio record button and the play button on the movie so you can do your voice over in sync with the movie.
- When at the end click the red button again to stop the audio recording.
- Make sure the movie position is at the start of the movie
- On the audio window, move the selection tabs to the start and end of the track and the position to the start of the track
- Now select the audio window and edit/copy
- Now select edit/add to movie
- You should notice now the movie has a new audio track in it and it should be about the same length as the movie
- Hit play to make sure everything worked, then savas to save your new movie with new audio.
Now, if you need to do some editing on the sound there is some additional work to do, I really like the open source program called audacity, it allows you to edit audio files of many formats. (make sure you install the wav export plugin from their home page in addition to the base package)
- Click file/export and choose sound to aiff, save this file somewhere you can find it
- Open audacity and do file open on this sound file.
- Now you can zoom in on the section you want to edit, you can select a section and use edit/silence to clear out caugh's and sneezes (I find this handy because it doesn't change the size of the audio)
- Once you are done editing, do export as wav, save this file somewhere you can find it.
- Now go to quicktime and open the wav file in quick time, then follow the procedure above for importing audio into a movie (steps 8-11)