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Multiple Delivery Mechanisms for Streaming

Progressive Layering of Downloads
Another technique that spawned numerous articles and press mentions but has fallen by the wayside offers an enhancement to peer-to-peer networks. IPV, a UK company, created a technology several years ago called FMA. This technology, originally designed for the non-linear editing market, created QuickTime movies that could be downloaded by quality layers rather than sequential frames. If the end user chose to watch the movie from a particular point, the FMA technology would weight its downloading efforts to that particular portion of the movie, in essence, creating a full-quality version at the point of viewing while the rest of the movie "filled in" around that segment as bandwidth permitted.

Unfortunately, the technology worked only with files that had been previously transcoded into a proprietary FMA format and would play back only in QuickTime. The concept had no raison d’ĂȘtre for other streaming formats until the advent of efficient peer-to-peer technologies such as BitTorrent.

Flash
Much has been written about Flash Video and the ability to encapsulate video within a Flash file. The benefits are numerous, given the similarities between MPEG-4 systems and Flash technologies in terms of combining interactivity and video. Flash holds promise for immersive interactivity that mimics the gaming industry’s drive toward complex but intuitive interfaces.

But Flash also has a limitation that once plagued media download products like early implementations of QuickTime. If one chooses the most common option, embedding video within the Flash (.swf) file, the entire Flash file has to be downloaded prior to playback. Flash can also perform progressive downloads with a pre-encoded Flash Video (.flv) file, or the .swf file can contain a pointer to an external video file that would be streamed from the Flash Communications Server. But these implementations aren’t as prevalent as embedding the video directly within the .swf file. If the Flash dog can be trained to do new tricks in terms of content delivery and playback, and if it is coupled with a move from H.263 (Flash’s native video format) to H.264, then Flash should find itself on equal footing with other delivery models.

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