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What is an IntelliStar and What Does It Do?

An IntelliStar must perform two major tasks concurrently. First, it must collect weather data from the satellite feed and store the data relevant to the location it is configured for. This data includes current observations, radar images, satellite images, and several different forecasts. Second, the device must display this weather data to viewers at broadcast quality that compiles with FCC regulations. This includes rendering both full screen video as well as being able to render graphic objects on top of a live video feed. When a box is down, it can not deliver local content on the analog output and can not deliver any digital output, so down time is very visible to customers and must be avoided.

In addition, since other networks do not deploy devices to head ends to generate localized content, an IntelliStar must operate as a ``black box'' from a cable head end technician's perspective. For example, head end technicians are accustomed to using the power button to turn things off, so the device must handle powering off via the power button gracefully. Also, the device must operate without having a keyboard, mouse, or monitor connected. Finally, the device should not require any interaction from a head end technician beyond using the power button to power the device on and off.

In addition to these requirements, TWC wants to take advantage of recent technology innovations. The current generation of STARs, known as the WeatherSTAR XL, are built from SGI boxes running IRIX with additional proprietary hardware. The IntelliStar, on the other hand, is built largely from commodity PC hardware with limited proprietary hardware. This has resulted in a cheaper and more compact device that is easier to upgrade in the future. For example, the actual rendering of video content is done using the hardware acceleration of an off-the-shelf AGP graphics adapter. Should the need for more rendering horsepower arise in the future, the graphics adapter can be replaced with a newer adapter without any changes needed in either proprietary hardware or software. To accomplish this goal, much of the realtime requirements for audio and video have been offloaded into proprietary hardware.


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Next: Why FreeBSD? Up: Using FreeBSD to Render Previous: Introduction