Working on an iDVD project recently, I decided to take advantage of Keynote 2's wonderful graphical abilities and create a self-running slideshow to include in my project. Keynote will export slideshows as a quicktime movie, but it separates the audio and video tracks, thus creating a problem inserting it into my iDVD project. I figured I would simply combine the audio and video tracks in iMovie HD and save the result as a .dv file for iDVD.
Well, I could not not make the resulting movie look like crap, no matter what settings or codec I used. After some research, I was assured that iMovie's "preview" was causing the movie to look bad. This answer seemed silly to me. What else are you going to do with a movie other than look at it? And if the QuickTime player could display the movie crisply and without artifacts, iMovie (or Final Cut Pro for that matter) should be able to as well. Not so.
Anyway, I spent a lot of time trying to figure this out. I didn't want my beautifully crafted movie/slideshow to look like garbage in my DVD project. I had finally just decided to leave it out completely when a possible solution occured to me. I explored Quicktime Pro a bit, tried it, and it worked. The solution does require that you have Quicktime Pro. Open both the exported audio and video files and with the audio file in front, choose Extract Tracks from the Edit Menu. Choose the only listed audio track, click Extract.
This will create a new window with the extracted audio. Ignore it and bring the video track to the front and choose Add Scaled from the edit menu and save. Viola! Your keynote quicktime video, intact with audio and video, looking as good as it did in keynote and ready to be imported into your iDVD project.
[robg adds: Based on my experience with Keynote2, I believe you'll only get the separate audio and video tracks when you've used the "audio well" in the Documents inspector to add your music as a background track that repeats through the duration of the show. If you have music that's just playing on one slide (i.e. it was placed directly on the slide), then you'll get a combined audio/video export. I also think, though I'm not positive, that the artifacts in iMovie are a result of it being limited to DV resolution, hence it scales the QT movie to 720x480.]
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