Step 1: Delivery Options
Before you can use Flash video on your site, you need to decide how to deliver the video; the two primary options are to deliver it as a progressive download or as a streaming video from your own Flash Media Server (formerly Flash Communication Server), or from a hosted server using Flash Video Streaming Services (see Figure 3).
Figure 3 Deployment screen of the Flash import video wizard, in which you choose your delivery option
You can also embed video in the Flash Timeline, but this is recommended only for very short video clips with no audio track that must be embedded into the SWF file.
These delivery options will be covered in much more detail in a later article, but for now, the following sections summarize each method.
Progressive Download
Progressive Download (FLV) enables developers to use ActionScript commands to feed external FLV files into a Flash movie and play them back during runtime. With this method, the video content is kept external to the other Flash content and the video-playback controls, which reside in the SWF file.
When the video is played, the video file is downloaded to the client’s computer before playback. However, unlike traditional download-and-play methods of video delivery, the file starts playing before it has completely downloaded.
Streaming Video (FLV)
As is the case with progressive download, when you use streaming video, FLV files are kept external to the other Flash content. You use ActionScript to feed these external FLV files into a Flash movie and play them back during runtime. The ActionScript code needed for streaming video is almost identical to that for progressive download.
This is where the similarities end, however. With streaming video, each client opens a persistent connection to the streaming server, and the server streams the video bits to the requesting client. Those bits are consumed by the viewer and then immediately discarded.
This tight connection between the server and client enables publishers to control every aspect of the video experience—including the ability to webcast live events, vary the streaming rates based on a visitor’s bandwidth, automatically create "chapters" from one long video file complete with appropriate thumbnails and navigation capabilities, and much, much more.