Real Networks
The stalwart of streaming media is Real Networks.
The G2 and later versions of the tried-and-true RealAudio technology supports streaming video as
well as audio, and boasts significant improvements over the previous RealPlayer 5.0.
The RealPlayer is also backwards-compatible with the various RealAudio formats. The core of Real Networks' business
is selling streaming media server software and production tools to encode this content. Most of these programs
are commercial, but there are free versions with limited features.
Real includes various features in their RealPlayer product such as clickable video where hot areas are defined on a video window. RN promises the ability to serve 500-1000 28.8 video streams from a single Pentium-based server, but they don't say what type of network connection that server would need. RealVideo supports IP multicasting, which allows multiple clients to view from the same stream of video - this is the same protocol which MBONE uses.
Currently RN is shipping a variety of encoding tools for creating files that their servers can stream. Most of these tools are commercial, but there are free versions of basic tools which can be downloaded from their site. There is a free Encoder, and another tool called the Publisher which costs about $50. The company promises technologies such as "smart networking" which can send data using whatever protocol is most efficient for a given user (i.e., to try to get through firewalls and whatnot), and "stream thinning" which dynamically adjusts video frame rates to deal with congested Net connections.
To encode RealVideo files you need to choose the bandwidth that you expect your users to have. This will sometimes lead you to create more than one version of the same file in order to provide your content to a variety of users. Encoding video files takes a long time, but it's very easy to do and the resulting compressed files come out very small. Links are constructed the same way as they are for RealAudio, so check out the page which describes how to do that at ITP.
Real Media Resources
Windows Media Technologies
Microsoft has just introduced a new suite of streaming media tools, called Windows Media. This tech
is based on a new format called the Advanced Streaming Format (ASF). Microsoft is offering a free player,
as well as a free (apparently) encoder designed to convert content from established formats such as MP3, AVI, WAV,
and others. To present this type of content, you would need to host your site on a Windows NT server equipped with
the Windows Media Services add-on components.
While the Windows Media brand is being promoted as a primarily audio technology, it will stream both audio and video.
Microsoft is touting quality superior to both MP3 and RealPlayer G2 file formats. Time will tell if users are willing
to switch to this new format. Some interesting features built into Windows Media:
Not too many record companies have expressed initial enthusiasm about Windows Media. One objection is that their player will play files in the dreaded MP3 format. Some sources suggest that the record industry doesn't want Microsoft anywhere near their business.
Sites using Windows Media
Apple's Streaming QuickTime
One of the features of Apple's OS X is a built-in streaming media server. Apparently this software
does not work under previous versions of the OS. Since OS X will probably considerably cheaper than
a commercial version of Real Server, this could be a very exciting development for streaming media when
OS X officially is released in 2001.
The big players like Apple and Real are not the only companies coming out with streaming content protocols. Check out these lesser-known possibilities:
Graham Technology Solutions has developed a means of streaming a series of JPEGs to the screen at a rate which comes very close to video. This concept was developed in association with Thinking Pictures in their Rock.com project.