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Chapter 7: Media Preparation and Delivery
Audio compression
With any of the Flash Video encoding utilities, you can encode the audio chan-
nel of your source file with MP3 compression, which supports stereo sound and
higher bit rates than the Speech codec.
Regardless of how you create the FLV files used by your FlashCom application, you
can view any FLV files over HTTP with the progressive download option for Net-
Stream instances in Flash Player 7. Refer to the Preface for details on how this option
differs from streaming support provided by FlashCom.
The Screen Recording Codec
One of the benefits of the Flash Video Exporter over other third-party FLV encoders is
the capability to encode FLV files with the Screen Recording codec. As its name
implies, this lossless codec is designed to work with desktop screen captures. If you
have recorded an AVI or MOV file of a task performed with a desktop application (e.g.,
a tutorial video demonstrating how to use a program such as Flash MX 2004), you can
create a compressed FLV file with the Screen Recording codec for optimal clarity of
screen details. Make sure you use a low frame rate (6 to 10 fps) and a high keyframe
interval (60 or higher) to keep your FLV bit rate from being too demanding for your
target audience’s bandwidth availability.
Converting Prerecorded Material
to FLV Format
It’s not very likely that all of the audio/video material you want to stream to your
users was recorded by your FlashCom Server. Chances are, you’ll have content that
you’ve recorded with other higher-quality capture sources, such as a mini-DV cam-
corder or video output from 3D modeling applications. Your business clients may
even provide you with high-quality video footage for movie trailers, sports or news
clips, or product demonstrations. Most of these files are not going to be in a digital
video format directly supported by FlashCom. For that reason, you’ll need a way to
convert disparate video formats to the FLV file format, the only one that FlashCom
If you need some sample video content to convert to FLV files, you
can download sample Windows AVI and QuickTime MOV files from
the book’s web site.
Recompressing Video Files
A sure sign of a less than ideal digital video workflow is the act of recompressing dig-
ital video files that have already been significantly compressed with some other

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