Web Design in a Nutshell, 3rd Edition

RealMedia (.rm)

RealNetworks (which used to be Progressive Networks) first launched its streaming video capabilities in Version 3.0 of its RealMedia line of products (of which RealAudio is the star component). RealMedia files (.rm) are viewed using RealPlayer. The wide distribution of RealPlayer makes RealMedia a popular choice for adding streaming media to a web site.

The components of the RealMedia system (RealPlayer for playback, Helix Server for serving simultaneous streams, and RealProducer and RealProducerPlus for creating .rm files) are the same as for RealAudio. RealMedia movies are encoded using a proprietary codec built into RealProducer and RealPlayer.

For more information, visit the RealNetworks site at http://www.realnetworks.com. For consumer-oriented information and downloads, see http://www.real.com.

The following summarizes the RealAudio format:

Good for...	Long-playing video clips and live broadcasts to large numbers of people.
Delivery	Streaming (via RTSP), pseudostreaming (via HTTP).
Creation tools	One of the RealNetworks encoders (such as RealProducer Plus or Basic) or a third-party tool such as Autodesk Cleaner. A plug-in is available for Final Cut Pro, Adobe After Effects, and Avid Xpress for exporting to RealMedia format.
Player	Freely available RealPlayer and commercial RealPlayer Enterprise.