Codec Central - RealMedia for the World Wide Web



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RealMedia

The RealMedia architecture was developed by Progressive Networks, makers of RealAudio. It was designed specifically to support live and on-demand video and audio across the WWW.

The first version of RealMedia is focused on video and audio, and is referred to as RealVideo. Later releases of RealMedia will incorporate other formats including MIDI, text, images, vector graphics, animations, and presentations.

RealMedia content can be placed on your site either with or without special server software. There are performance advantages with the server, but you don't have to buy one to get started. However, high volume sites will definitely want a server to get substantially improved file delivery performance.

Users can view RealMedia sites with the RealPlayer, a free "client" application available from Progressive. A Netscape plug-in is also available.

The main downside to RealMedia is that it currently requires a PowerMac or Pentium computer to view. As such, RealMedia movies aren't available to the full range of potential users.

The latest free downloads, as well as more information, are available at Real Network's site.

RealVideo Codecs

Codec (Primary Use)	Pros	Cons	Availability
RealVideo (Standard) WWW video below 3KBps	Encodes quickly; better at lower data rates & higher action	Requires high-end PowerMac or Pentium for proper playback	Included with RealVideo Encoder
RealVideo (Fractal) WWW video above 3KBps	Plays better than RealVideo (Standard) on lower-end systems; higher quality for scenes with less action.	Still requires mid-range to fast PowerMac or Pentium for proper playback; no live encoding.	Available from Iterated Systems

RealAudio Codecs

Codec (Primary Use)	Pros	Cons	Availability
Voice	Extremely low data rates allow use over 14.4 modem, or leave more bandwith for video	Don't accurately reproduce music or sound effects	Included in RealVideo Encoder
8, 12KBps Music	Acceptable reproduction of music, especially instrumental-only	Mono only; not as good on vocals	Included in RealVideo Encoder
High bitrate Music	Very good reproduction of wide range of music	Requires faster connection	Included in RealVideo Encoder