How does ASF relate to older formats such as MPEG-1, MPEG-2, and QuickTime?

MPEG-1 and MPEG-2 each define codecs and a file format. Each provides a framework for delivering digital video over a network with a bandwidth well over 1 Mbps (in other words, really fat pipes). MPEG-1 and MPEG-2 do not support media types other than video and audio. Put simply, if all you want is video, and not any other kind of media, and you have really fat network pipes at your disposal and no one will complain too loudly when you are hogging those pipes with MPEG-1 or MPEG-2 video, then MPEG-1 and MPEG-2 are fine systems for delivering digital multimedia. However, trying to shove MPEG-1 or MPEG-2 files down the pipes of the Internet is like trying to fit the proverbial square peg into the round hole.

QuickTime is a multimedia file format and much more. It is a format for directly capturing digital multimedia, for editing that media, for delivering that media, and for playing back that media, and it includes a framework and a set of tools for assisting in this. If streaming synchronized multimedia presentations is like boating, then ASF is to QuickTime what a motorboat is to a floatplane. Sure, you could fly the floatplane through the air and then putter around the lake in it. But you would be better off sticking to flying the floatplane and then hopping into the motorboat upon hitting the water. Similarly, QuickTime is fine for capturing and editing a multimedia presentation. But when that presentation is ready to hit the network pipes and be streamed to clients, it is time to save that presentation as an ASF file and let ASF take it from there.

That MPEG-1, MPEG-2, and QuickTime fall short when it comes to streaming multimedia presentations over the Internet is evidenced by what has happened in the streaming media market over the past few years. Over this time, a number of companies have emerged with the express mission of providing technology for streaming media over the Internet. Each of these companies faced the same choice: either try to use MPEG-1, MPEG-2, QuickTime, AVI, or some other older format, or develop a new format from scratch. All of the key players made the same choice -- each developed its own format. (See How does ASF relate to newer formats such as VXF, RA, RMFF, and VIV?).

Each of the key streaming industry players independently reached the same conclusion: the older formats did not do the job in the world of Internet streaming multimedia. Specifically, the older formats come up short with respect to the key features that mark a good streaming multimedia format. We introduced these features earlier in What makes ASF good? The following table indicates where MPEG-1, MPEG-2, QuickTime, and ASF stand with respect to being adequate in terms of these key features:

Although ASF will make AVI obsolete, the same is not true for MPEG-1, MPEG-2, or QuickTime. These formats will still have their use and place. For example, ASF can store content encoded using the MPEG-1 and MPEG-2 compression schemes, and then extend this content by synchronizing it with other media types. Similarly, content captured and edited using QuickTime can be saved as an ASF file. In sum, ASF will take over from MPEG-1, MPEG-2, and QuickTime when a file format is needed for streaming and playing back a multimedia presentation over the Internet, an intranet, and/or from a local source.

AVI, MPEG-1, MPEG-2, and QuickTime laid the groundwork for the digital multimedia revolution. Next up: the newer multimedia streaming formats, such as VXF, RA, RMFF, and VIV, which made the revolution imminent.

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