Streaming Video: Internet Broadcasting for the Masses

During the dark ages of the early 1990's, people waited many minutes to download video clips from the Internet. Finally, someone thought, "Why don't we watch one part of the video while the rest of it downloads?" Thus streaming video, a system of special compression and buffering techniques was born. It allows you to transmit real-time video over the Internet to an exponentially expanding worldwide audience.

You may ask yourself "What does this have to do with me? I'm not a computer person." But if you're a videographer, you might be interested in a way to present your work to a potential audience of millions. After reading this article, you'll understand:

• what streaming video is,
• how to shoot video for streaming,
• how to digitize and compress the video onto your hard drive, and
• why you need a streaming server.

So keep reading and step into the future of video.

To view a streamed video file from the Internet, you need to install a plug-in (special helper software that works in conjunction with your Web browser to handle the downloading and decompression of the video). To perform the miracle of transmitting and receiving video and sound through a phone or high-speed data line, streamed video uses a nearly magical formula of compression and buffering.

To compress video, a complex mathematical formula breaks the video into individual frames. Each frame is broken into moving and static components. Compression software takes each moving object and guesses where it will be in the next frame. By refreshing only the moving components of a frame, and recycling the static, compression reduces the size and transmission time of the video file. Similarly, in The Flintstones, the animators saved countless hours by drawing only the moving parts of each frame. Fred's mouth was often times the only thing moving in a scene, thus that was the only part actually redrawn for a frame, the rest was recycled from the previous frame. There is a downside to compression. If the camera is panning, zooming, or moving in any way, the whole image is in motion, leaving nothing to recycle. This leads to poor compression, and slower transmission.

Compared with the voodoo magic of compression, buffering seems fairly bland. By giving the file a few seconds to load before starting to play, a reserve of video is available in the memory of the viewing computer in case the transmission slows for a moment. When the transmission slows, the viewing computer uses part of the reserve of video. If the transmission becomes too slow, the buffer completely exhausts itself, and the video plays at a lower frame rate and becomes choppy. Better streaming packages will adapt the buffer size to the speed of the connection, even as it fluctuates with the normal ebb and flow of Internet traffic.

Streamed video is heavily compressed, so your goal is to maximize the quality of the video, while minimizing the amount of digital artifacts and choppiness that will inevitably occur in a streamed video.

Remember that if the camera is moving, everything in the shot is moving too. To keep your streamed video from slowing down, shoot images with very little motion and use a tripod. Avoid high-motion shooting techniques, such as panning and zooming. This is not to say that you must eliminate all motion in your shots, but try to make sure that the only thing moving is the main subject.

The colors you choose can also affect how well your video will compress. Bright solid colors are best. Dark colors can confuse the compression software by blending together with subtle shadows. The contrast of colors is crucial too. Choose subjects that contrast distinctly from their backgrounds. Patterns, either in the foreground or background, must be constantly refreshed when there is the slightest movement.