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Careful planning and organization at the start of your project is important to the success of your live broadcast. The three primary steps in this process are: event preparation, input media preparation, and encoder preparation.
Regardless of the type of live broadcast event, you should set a predetermined start and end time. By setting a start time, you can let your audience know when the broadcast will take place.
Placement of the broadcast equipment is also an important factor in the planning process. The movement of your digital media capture device is restricted by the cable that connects it to the encoding computer. The encoding computer, in turn, must be networked to the computer running Windows Media Services, which of course must have access to a network or the Internet so that your audience can receive the stream.
If you intend to broadcast or rebroadcast copyrighted material, ensure that you have the proper permissions and licenses.
Input media can consist of a capture device, such as a digital video camera or a microphone, or a feed from a media source, such as a television signal. Be sure that your capture device has a digital output signal or that you have the proper equipment for generating a digital output. Many camcorders and video cassette players are not compatible with the digital input requirements of an encoder, such as Windows Media Encoder.
You must know how your equipment operates. Practice your event beforehand to avoid mishaps during a live broadcast. Ensure that all batteries are sufficiently charged and that any required equipment maintenance has been performed.
Bit rate is the main concern when streaming digital media of any type. The bit rate affects both the range and number of people that will be able to experience your broadcast. In general terms, a low bit rate will allow you to reach the widest audience and permit the largest number of individual connections, but quality can suffer. Higher quality requires a higher bit rate, and the number of individual connections is limited.
Remember that audio and video encoding of live content occurs in real-time with no opportunities to change settings once you have begun. You should practice your broadcast beforehand to determine the proper encoder settings.
Live audio broadcasts are typically a simple encoding scenario. Even so, a high-quality stereo broadcast can easily overwhelm a standard dial-up modem connection. There are several configurable components of an audio capture that can be adjusted during the encoding process to help you achieve the right balance of bit rate and audio quality. For more information about how audio content is prepared for streaming, see Windows Media Encoder Help.
Encoding video content is a much more complicated process. Video is simply a rapid display of a series of still pictures, called frames. Each frame must display a certain amount of detail, or resolution, to render the subject accurately. As the frame resolution is enhanced, more detail is shown. The number of frames displayed per second is known as the frame rate. As the frame rate increases, the motion in the video becomes smoother. The bit rate of the stream is determined by the combination of video frame rate and resolution. Both of these parameters can be modified during the encoding process to achieve the ideal bit rate for the user.
Over a high speed Internet connection or a LAN, smooth, high-resolution video is readily available. Extremely fast networks can render video and audio that can rival the quality of a DVD; however, over a typical dial-up connection, high-quality video becomes impossible without prohibitively long buffering times. There are techniques that you can use during the production of your live video content that will improve the audience experience regardless of the type of connection being used:
For more information about encoding, see Windows Media Encoder Help.