First thing would be that I needed to figure out how to get a human walking across a virtual background. As you can see in the Macromedia version, there is a female walking across the stage and viewing "pictures" in the gallery of Flash videos. Which in turn, change to video when she stops to look at it. The first thing I thought when I looked at it was how they created a video file that could play over graphics. You would need to support alpha channels, and as far as I knew this wasn't possible to do with FLV files. So I started experimenting with PNG files, but quickly realized that you would need a lot of PNG files to create a video that long. This isn't a viable approach.
If PNG's aren't viable, that left me to assume that it is an FLV file. How do I know it's an FLV? Looking in my internet files cache directory I couldn't find any file that would be that video which means that it is being streamed by Flash Communication Server. Which means? it's one file! The whole thing, all three videos and graphics are one file! OK, so now this makes it much easier. I now know exactly what I needed:
A video of a person walking across a stage looking at the "pictures"
2 videos, one must be somebody talking to the monitor and the other must be something TV or movie style
Background graphics
Flash movie "holder" to play the flv file
The one doubt I still had was to how to make the video so clear that artifacts wouldn't start showing up for the graphics. This generally looks like "smudges" in the pixels which would make it look a little less real and not what we are shooting for. This problem was tackled with the excellent encoding of Sorenson Squeeze. I'll go over that a bit more later.
First off was the hardest part, shooting the video for the "virtual walk".
This is done by using a key. A key is when you put a certain color behind the actor when taking the video and then erase it out later leaving just the actor. When you do this, you are left with an alpha channel which means you can now put anything behind the actor. Common colors for keys are "chroma"
colors which are generally a choice of 2 - blue or green. Depending on the clothes of the actor you would want to choose one or the other, it's mainly a preference of the director which one to use though. Keeping in mind though that for DV cameras, which is what I shot with, green tends to key out better later which is why I use green. A quick note on keying, I won't go into that much detail as there are way better resources out there on the issue, is that it can be done during production or post-production.
Expensive equipment is required for keying while shooting so... I didn't do that here. I did my keying in After Effects after I brought the video in with Premiere..
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