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Streaming Movies
Video streaming, to be precise Streaming Movies are one of the most exciting applications on the Internet. It already created a new business known as Internet broadcast, or Intercast/Webcast. Although Internet broadcast is still in its infancy, we get a glimpse of the future of broadcasting where people can enjoy not only scheduled live or pre-recorded broadcast but also on-demand and personalized programs. Stirring more excitement is the idea that anyone will be able to set up an Internet TV station and broadcast his or her video programs on the Internet just like we publish our “homepage” on the Web today. While Streaming Movies as a core technology behind a new business is a success story, it remains very much a black art owing to its root in proprietary commercial development. Indeed, to the author’s knowledge, there has been no published research literature to date that offers a comprehensive review of Streaming Movies architecture and system, and related design issues.
Streaming Movies involves sending movies from a server to a client over a network such as the Internet. The server breaks the movie into packets that can be sent over the network. At the receiving end, the packets are reassembled by the client and the movie is played as it comes in. Streaming in Streaming Movies is different from fast-start download in that the client plays the movie as it comes in over the network, rather than downloading the entire movie and playing it as it is being downloaded. Streaming Movies are never actually downloaded; its packets are played as they come in, and then discarded.
Streaming Movies files usually come in one of the following formats. QuickTime, Mpeg, Avi, Shockwave, Animated Gif Images, Flic movies, and a new development Real Video. You should become familiar with each of these file formats as different software is required to run each type of movie. The Software used to play movie files are normally called movie players or movie viewers, some movie players will run several of these different movie formats but as yet not one will run all of them.
QuickTime movies can be streamed using a variety of protocols, including HTTP (Hyper Text Transport Protocol) and FTP (File Transfer Protocol).
HTTP and FTP are essentially file transfer protocols. Any QuickTime movie saved using the QuickStart option can be streamed using these protocols because the QuickTime client software is able to start playing the movie before the entire file has arrived.
New QuickTime 4: RTP (Realtime Transport Protocol). RTP is used for real time streaming. The movie packets are sent in real time, so that a one-minute movie is sent over the network in one minute. The packets are time-stamped, so they can be displayed in time-synchronized order. Because packets are sent in real time, RTP streaming works with live content in addition to previously-recorded movies. It can even carry a mixture of the two. Real-time streams can be sent one-to-one (unicast) or one-to-many (multicast).
Streaming Movies files are distinguished from each other and from earlier and later versions by their file extension. A file extension is the last part of the name of the file - for example: kong.mpg is telling you that the type of movie is an mpg or mpeg movie and we will need to have a mpeg player/viewer to watch that movie.
The nascent streaming media market is allowing companies like Medium4.com and CinemaNow to deliver a wide variety of Streaming Movies to consumers on their PCs. Other ad supported Web sites offer not only Streaming Movies and short features, but streaming advertisements as well. And the streaming media market has its own lingo such as "constant bit rate" and "digital rights management." CED's online extra on streaming media talks about a couple companies that offer streaming movies and virtual channel changing, the top 10 ad-supported streaming sites and a glossary of streaming media terms.
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