26.3. Creating Flash Movies
Full-featured Flash movies are best created using
Macromedia's Flash software. Obviously, it is beyond the scope
of this book to teach the ins and outs of Flash authoring, so I
recommend using the tutorials that come with the software as well as
support documents provided by Macromedia (http://www.macromedia.com/support/flash/).
For an incredibly thorough book of tutorials and reference material,
check out Flash 5 Bible by Robert Reinhardt
and Jon Warren Lentz (Hungry Minds, 2001).
26.3.1. File Formats
The Flash authoring tool saves information about a movie in a
.fla source file (also called a
"Flash document" or "Flash editor document").
The .fla file contains all the separate elements
that make up the movie and its timeline information in a fully
When the movie is ready to go on the Web, it must be exported to
.swf format. The suffix originally stood for
"Shockwave Flash," but in the face of confusion with
Macromedia's Shockwave for Director format, Macromedia has
changed its tune and now translates
"Small Web Format."
This new moniker is accurate. In the export process, the information
from the original layered .fla file is flattened
down to one layer and one timeline. The resulting file packs a lot of
multimedia punch in a size that is appropriate for the Web.
26.3.2. Flash Interface Basics
As noted earlier, it is beyond the scope
of this book to teach Flash. However, it is useful to be generally
acquainted with the Flash authoring environment. Figure 26-1 shows the core features of the Flash interface
as seen on a Macintosh (the Windows version is nearly the same). The
following is a brief introduction to the way Flash handles multimedia
Figure 26-1. The Flash interface
The Stage is
the area where you compose and preview the movie.
The elements on a timeline may be stored on
separate layers (similar to layers in image editing tools). Layers in
Flash control the arrangement of objects from background to
foreground, support masking, enable motion and shape tweening, and
contain guide elements, frame labels, and actions.
need only have one scene, but smart developers use scenes to better
organize content. Scenes will play in sequential order by default.
They may also be scripted to play based on user input (called an
Action), like a rollover or a button click.
The Timeline is where you control the timing
of the animation and assemble the elements from separate layers.
Flash movies divide lengths of time into individual frames. A
keyframe is a frame in which you define a change in the animation.
Static frames reflect no change and merely repeat the content of the
prior frame. Animation effects are added by changing content over a
series of frames. The most efficient (both in terms of production
time and processing power) method for adding animation is
tweening, in which you create the beginning and
end keyframe images and allow Flash to automatically create all the
frame "in between."
is where you store all imported items (such as images and audio) and
symbols, Flash objects that you want to use
repeatedly in the same movie (such as a button shape with its various
interactive states). When you place a symbol on the Stage, you create
an instance of that symbol.
The Controller contains the typical buttons
for playing, pausing, and stepping through the frames of a movie when
previewing it on the Stage.
contains all the tools for drawing, painting, selecting, viewing, and
modifying artwork. Additional tools are available in individual
floating panels that can be shown, hidden, or collapsed into a small
bar until needed.
26.3.3. Optimizing Flash Movies
a number of measures you can take up front to make your
.swf compress as small as it can. The following
are just a few tips:
Keep your artwork as simple as possible.
Remove unnecessary points in vector drawings (choose
"Optimize" from the Modify menu).
Limit the number of gradients (choose flat color fills instead).
Limit the number of fonts and amount of text.
Use "tweens" and motion guide layers for animation rather
than extra keyframes.
Minimize bitmap usage and avoid setting bitmap images in motion.
Use symbols and nested symbols whenever possible. However, do not
allow symbols to be too large as they can slow down streaming
Optimize imported media (images, audio) prior to placement in Flash.
Use MP3 compression for audio whenever possible. It is recommended to
save the audio in MP3 before importing, rather than importing raw WAV
or AIFF files.
It is a good idea to use Flash's Test Movie or Test Scene
functions to check your movie's performance. The Bandwidth
Profiler simulates various connection speeds. You can also generate
size reports to check the size of media components within the movie
(it may reveal elements that could be optimized better).
26.3.4. Configuring the Server
Although no special server
software is necessary to serve standard Flash files, you will need to
configure your server to recognize a new MIME type. The specific
syntax for configuration varies for different servers, so coordinate
with your system administrator and see Macromedia's site for
support information. The following information will suit the needs of
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