Technical information

by Forest Key and Chris Hock
11
Performance Audio and video synch is
limited after approximately
120 seconds of video. Total
file duration is limited to
available RAM on the
playback system.
Improved performance over
embedded SWF video, with
bigger and longer video and
reliable audio
synchronization. Provides
best image quality, which is
limited only by the amount of
available hard drive space on
the playback system.
Improved efficiency from a
web delivery perspective,
with optimal bit rate delivery
on an as-needed basis to
as many customers as
necessary. Image quality
limited to bit rates that can
be delivered in real time.
Usage Shorter video clips (less
than 1 minute) that are
smaller (less than 320 x
240), and have a lower
frame rate (12 fps).
Longer video clips that are
bigger (720 x 480 and
greater) and have a higher
frame rate (up to 30 fps).
Large quantities of video,
very long video clips, and
live and multiway streaming
(such as webcam chat and
live event broadcasts).
Compatibility Flash Player 6 and 7 Flash Player 7 Flash Player 6 and 7
Using Live Video
The Flash video platform not only enables the use of recorded video—with
Flash Communication Server, you can use live video as well. Flash Player 6
and higher include a video encoder that can capture video from a webcam
or DV camera and publish that video to Flash Communication Server. The
communication server can then publish that video to any Flash Player client
(or any other Flash Communication Server) that subscribes to the stream.
A typical scenario for broadcasting a live video event would be as follows:
• The developer creates two applications (SWF files) with Flash – a
broadcaster application and a viewer application.
• The video producer connects a DV or web camera to the broadcast
machine through USB, Firewire, or a video capture card, and the
broadcaster application (broadcaster swf) publishes the live video
stream.
• Clients who want to view the live stream run the viewer application on
their local machines.
This scenario is an extremely simple example of what you can do with Flash
Communication Server. You can create even more compelling applications
such as webcam chats, video messaging applications, and virtual
classrooms. All of this is because Flash Communication Server provides
multiway streaming to multiple clients; data streaming; video capture and
recording on the server; and much more. Visit
http://www.macromedia.com/software/flashcom/ for more information on
using live video and advanced streaming features.
Creating Flash Video Files from within
Third-Party Applications
Flash MX Professional 2004 includes Flash Video Exporter, which enables
many third-party applications to encode video and audio directly into the