Web Design in a Nutshell, 3rd Edition

Windows Media (.wma, .asf)

Microsoft’s Windows Media is a streaming media system similar to RealMedia. Like RealMedia, it comes with the standard components for creating, playing, and serving Windows Media files. Windows Media wraps all media elements into one Active Streaming File (.asf), Microsoft’s proprietary streaming media format. Audio may also be saved as nonstreaming Windows Media Audio format (.wma). Because Media Player is part of the Windows operating system, it is widely distributed and stable on the Windows platform. A version of Media Player is available for the Mac as well, but it generally lags behind the Windows release and may not support the latest Windows Media codec standards.

Windows Media Audio files are encoded using the special Windows Media Audio codec (currently in Version 9), which is ideal for all types of audio at bit rates from 16 Kbps to 192 Kbps. For voice-only audio at low bit rates (8 Kbps), use the alternative ACELP codec.

The Windows Media system has its advantages and disadvantages. On the good side, the server software comes free with Windows NT Server 4.0 and later, and there are no charges for streams as there are with RealMedia. Administration tools make it easy to track performance and bill per view or per minute. The disadvantages to Windows Media are that the server only runs on Windows NT and it doesn’t support Flash or SMIL (Synchronized Multimedia Integration Language) like RealMedia.

For more information on Windows Media, see http://www.microsoft.com/windows/windowsmedia/default.mspx ...