Streaming 101: The Basics
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In general, streaming media refers to the ability to deliver video, audio and presentations, such as PowerPoint, that play immediately when accessed, without requiring a full download before playback.
Streaming content delivery falls into two main types: live multimedia broadcasts (often called Webcasts), or archived video and audio accessed "on demand" by users.
In simple terms, the process of getting from raw footage to streamed content works like this:
- An event is recorded.
- The content is edited, then digitized using video editing hardware and software.
- The digital video and audio content is encoded for streaming. The most widely recognized encoding standards are Microsoft Windows Media and Real-Networks RealVideo. Tools and software also exist to encode for Vivo, AVI, QuickTime and MPEG.
- The media file or live stream is stored on a host computer that has streaming media server software installed.
- A user clicks a link on an intranet page to request a video stream or accesses a database of stored streaming content.
- The host server delivers the digitized content to the end user, who watches it through a player utility (such as Windows Media Player or RealPlayer) that displays the media file on the desktop.
Outsourcing may ease transition
Though a few larger firms may prefer to handle the entire process, there's ample opportunity to outsource production steps to third parties. Companies that do not own video production equipment and have no desire to invest several thousand dollars in establishing a studio may hire an outside firm to light, film and capture individual events, and purchase edited, digitized footage ready for encoding. Encoders are readily available from RealNetworks, Microsoft, and third-party vendors, such as Adobe and Sonic Foundry, but service providers such as Encoding.com can manage the encoding process and deliver a finished product in the streaming format you specify.
Content delivery could have a major impact on your network. Companies unprepared to deal with the additional network configuration and bandwidth issues, or those that would prefer to assess the effectiveness of streaming media on a smaller scale before spending thousands to upgrade a network, can tap service providers such as Broadcast.com, Network 24 and InterVU to host and deliver streaming content remotely, via a direct LAN connection or across the Internet.
The most significant caveat to the use of streaming media in place of traditional videotape or broadcast mediums is quality of playback. According to Optibase, a video hardware company, uncompressed video running full screen, full motion (30 frames per second) on a network could use up to 200M bit/sec at a sustained rate. Even an MPEG 1, Layer 3 encoded video eats up approximately 1.2M bit/sec.
Most companies do not have enough available bandwidth to sustain more than a handful of users at this rate, and excessive traffic on the network can result in a jittery picture and out-of-sync audio playback.
Network managers will need to experiment to find the best combination of video compression for playback quality. It may also be worthwhile to encode multiple versions of content compressed at different rates to address different bandwidth and companywide traffic conditions, or to develop audio-only or multimedia presentations for delivery to remote locations using low-bandwidth connections.
