Next: Introduction

Using FreeBSD to Render Realtime Localized Audio and Video

Abstract

One of the largest selling points for The Weather Channel (TWC) is the ability to generate localized content for its subscribers, specifically local weather forecasts. To facilitate this localized content, TWC deploys smart devices in cable head ends. These smart devices are called STARs (Satellite Transmitter Addressable Receivers) and are responsible both for collecting weather data and displaying the data to the user in an audio and video presentation.

TWC decided to produce a next generation STAR that was more flexible than the current generation as well as cheaper. FreeBSD was chosen as the platform for these devices. Although FreeBSD was largely suitable for this application, a few modifications were required and several workarounds were employed. The end result is a PC built mostly of off-the-shelf components that is able to render broadcast quality audio and video in realtime.

• • Abstract
  
  
• Introduction
• What is an IntelliStar and What Does It Do?
• Why FreeBSD?
  • VM Stability
  • Compiler
  • Self-Contained OS
  
  
• Changes from stock FreeBSD
  • Backporting ACPI
  • Sharing sio PCI Interrupts
  • Increasing Size of Socket Receive Buffers
  • Scripting Enhancements for sysinstall
  
  
• Workarounds for FreeBSD Problems
  • Nice is too Unnice
  • Userland Threads
  
  
• Conclusion
• Acknowledgments
• Availability
• Bibliography