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Chapter 20: Working with video

Flash® video is one of the standout technologies on the Internet. However, the traditional presentation of video—in

a rectangular screen with a progress bar and some control buttons underneath—is only one possible use of video in

a Flash application. Through ActionScript™, you have fine-tuned access to and control over video loading, presen-

tation, and playback.

Contents

Basics of video . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397

Understanding the Flash Video (FLV) format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398

Understanding the Video class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399

Loading video files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400

Controlling video playback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400

Streaming video files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402

Understanding cue points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402

Writing callback methods for onCuePoint and onMetaData . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403

Using cue points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408

Using video metadata . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408

Capturing camera input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411

Advanced topics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417

Example: Video Jukebox . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418

Basics of video

Introduction to working with video

One important capability of Adobe® Flash® Player is the ability to display and manipulate video information with

ActionScript in the same way that you can manipulate other visual content such as images, animation, text, and so

on.

When you create a Flash Video (FLV) file in Adobe Flash CS3 Professional, you have the option to select a skin for

your video including common playback controls. However, there is no reason you need to limit yourself to the

options available. Using ActionScript, you have fine-tuned control over loading, displaying, and controlling playback

of video—meaning you could create your own video player skin, or use your video in any less traditional way that

you want.

Working with video in ActionScript involves working with a combination of several classes:

• Video class: The actual video content box on the Stage is an instance of the Video class. The Video class is a

display object, so it can be manipulated using the same techniques that can be applied to other display objects, such

as positioning, applying transformations, applying filters and blending modes, and so forth.

• NetStream class: When you’re loading a video file to be controlled by ActionScript, a NetStream instance is used

to represent the source of the video content—in this case, a stream of video data. Using a NetStream instance also

involves using a NetConnection object, which is the connection to the video file—like the tunnel that the video data

is fed through.