Media streaming is a method of making audio, video, music, graphics, pictures, text and other multimedia available in real-time over the Internet or corporate Intranets, with no download wait and with no file to take space on the users hard disk.

Streams can originate from a live source, such as a video camera or a radio station, or the source can be stored on the server.To stream media, a Real-Time Transport Protocol (RTP) is used for one-way streaming and a Real-Time Streaming Protocol (RTSP) is used for two-way communications.

One issue with media streaming is that it can be stopped by by firewalls or network address translation (NAT). HTTP tunneling could be a mean to solve this problem.

The following streaming media file formats are currently (january 2001) used:

• asf : Microsoft Windows Media
• asx : redirection file for Windows media .asf files
• wma : Microsoft Windows audio
• wax : redirection file for Windows audio .wma files
• rm : RealPlayer G2
• rpm : redirection file for RealPlayer .rm files
• mvr : IBM HotMedia
• mov : Apple QuickTime

RealPlayer is a component of Real System G2, an award winning streaming media platform from RealNetworks, the leader in media streaming technologies.

There are more than 155 millions RealPlayer's currently (october 2000) registered to Internet users. The basic version of RealPlayer can be downloaded for free, an enhanced version (RealPlayer plus) is available for 29,99 US $. Several accessories like RealJukebox and RealDownload are available in basic and enhanced versions. The current version (october 2000) of RealPlayer is version 8.

View an example movie file .

Windows Media Player 7 is a component of the industry-leading Microsoft Windows Media Technologies which consists of a set of content development tools (Windows Media Tools), a server for distribution (Windows Media Services) and a set of software development kits (SDKs). Windows media files may be encrypted and secured against unauthorized distribution via Windows Media Digital Rights Management (DRM) features. Microsoft offers a lot of tutorials and authoring resources to create content for the Windows Media Player.

Windows Media Player 7 comprises seven features in a single application:

• CD player
• audio and video player
• media jukebox
• media guide
• Internet radio
• portable device music file transfer
• audio CD burner

There are over 100 million players installed. Codec independence is one of the key benefits of Windows Media Technologies. The audio (ACELP.net and Windows Media Audio V2) and video (MPEG-4 V3) codecs included in Windows Media delivers the highest possible level of audio and video compression quality. A comparison with MP3 and RealNetworks G2 audio files can be found on the Globix Streaming Media Group web site.

The Windows Media Player, version 7, is available as a free download from Microsoft.

View an example movie file.

QuickTimePlayer is a component of Apple's platform-independent suite of applications, plug-ins and files for playing or interacting with a wide range of popular media formats. QuickTime is streamable, interactive, programmable, track-based and immersive. The basic QuickTime Player can be downloaded fro free, a professional version is available for 29,95 US $.

Besides the streaming delivery (RTP, RTSP), QuickTime offers also a Fast-Start option based on HTTP/FTP protocols (progressive download) which has some advantages in comparison to media streaming technologies.

The QuickTime Player is currently (january 2001) available in version 4.1. for Windows and Mac OS and as a public preview version 5 for MacIntosh. A small QuickTime application called PictureViewer is also available.

View an example movie file.

IBM's HotMedia Player is a component of the low bandwidth Java applet technology for placing rich media on web pages quickly without loading plug-ins. Targeted at e-commerce, interactive advertising and other applications that use rich media, HotMedia allows:

• streaming synchronized audio and video
• zooming and rotating 3D objects
• triggering events
• floating tool tips
• integrating QuickTime .mov files

HotMedia is currently (october 2000) available in version 3.5 on Windows and Mac platforms.

View an example movie file.

There are several other dedicated streaming players available, mainly for broadband video streaming, which are not as widely used as the four presented technologies.

RealNetworks offers several packages, tools and servers to create and distribute streaming media for Windows, MacIntosh and Linux operating systems:

• Real Producer Plus
• Video Editing Solutions
• Real Producer Production Bundle
• Real Server Plus
• Streaming Media Starter Kit
• Real Server Pro

The prices ranges from 149,95 $ to 2.999 $. A free Real Producer Authoring Kit is also available.

Windows Media On-Demand Producer is a media production tool that encodes Windows Media files from audio (.wav) and video (.avi) source files. After the content has been created, it can be streamed over the Internet or an Intranet using Windows Media Player. The layout is intuitive enough that anyone can feel comfortable using it with minimal training. On-Demand producer was developed in partnership with Sonic Foundry.

The Windows Media On-Demand Producer licence is available for free.

QuickTime Pro (29,95 $), available for Windows and Mac Os, is a must for QuickTime content creators. It adds editing, compression, file translation, interacting and other powerful features to the standard QuickTime package.

Apple offers also dedicated streaming servers (reflectors) and broadcasting software for live streaming. QuickTime Streaming Services is currently (october 2000) available in version 2.0.1. Version 3 is available as public preview and in an Open Source form (Darwin Streaming Server). A full palette of tools for creating and editing digital content with tutorials is also available.

IBM announced on october 25, 2000, updates to its innovative HotMedia authoring tool, adding new features and improved performance. The new version, HotMedia 3.5, makes it simpler for web developers to add interactive video, streaming audio, 3D, animations and panoramas to web sites.

HotMedia 3.5 is available for users to author on both Windows and Mac platforms. The resulting HotMedia single files can be viewed with any Java-enabled browser. HotMedia is currently available as a free download from IBM.

Stream Anywhere is the all-in-one software solution for developing high-impact streaming media for the Internet. Stream Anywhere encodes rich media projects to Windows Media Technologies and Real System G2 web stream formats, in multiple bit rates, in a single operation.

The current version 1.0c for Windows is obtainable from Sonic Foundry for 179,10 US $.

The following subjects are related to media streaming:

• video codecs
• audio codecs
• 3D streaming