Technical information

by Forest Key and Chris Hock
2
n
Immersive experiences. Flash Video is just another media type within
the Flash movie, allowing video to be layered, scripted, and controlled
just like any other object in the Flash movie. Flash Video is an integral
part of the experience, as opposed to a separate pop-up window that
interrupts the viewing experience!
n
Custom branding and programmability. Flash Video can easily be
reskinned to convey custom branding and unique controls, and can
dynamically adapt based on data-driven content (playlist, closed
captioning, navigation, meta data, and so on).
n
Ubiquity. Flash Video was introduced with Macromedia Flash Player 6 in
the spring of 2002. Since then, Flash Player has become the most widely
installed Internet video client, running over 90 percent of all Internet-
connected PCs (source: NPD research April 2003). By comparison,
Windows Media Player and Real Player have less than 60 percent market
penetration, and QuickTime Player has less than 40 percent. This
ubiquity ensures that Flash websites that use video will load quickly,
with no need for additional plug-in downloads.
Technical Overview of Video Standards
Many people creating Flash Video projects files have a background in web
design and desktop publishing, and might not have the technical
understanding of video necessary to achieve optimal image quality for their
video projects. This section explains the basic concepts and usage of video
parameters and standards. If you are already familiar with these standards
and the terminology, you can skip this section and continue with the
section "Introducing the Macromedia Flash MX 2004 Video Platform."
Video Standards—NTSC and PAL
The video that you see on your television screen follows standards
established in the 1950s when color television was first introduced. The
leading formats in use today are NTSC (National Television System
Committee) and PAL (Phase Alternating Line). Generally speaking, NTSC is
the standard used in the Americas and Japan, whereas PAL is used in
Europe, Australia, the Middle East, and Asi a.
Neither video standard is optimal for presentation on computer monitors;
each poses different challenges when you are trying to optimize video for
web delivery:
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Frame Size: NTSC and PAL have different image sizes, which differ from
the available image sizes of computer monitors.
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Frame Rate: NTSC and PAL have different frame rates for the display of
images, which are different than those used by computer monitors.
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Pixel Aspect Ratio: NTSC and PAL share a pixel aspect ratio (referred to
as D1 Aspect Ratio, which is essentially rectangular), but this ratio differs
from that used by computer monitors (which is square).
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Display: NTSC and PAL consist of two separate “interlaced” fields, while
computer monitors display “progressive” images.