Software Codec Systems

The most basic desktop systems use the PC s microprocessor and graphics card to handle the capture and compression of audio and video. They do this by running a special program called a software codec. This method is less expensive than using separate chips or boards for the important task of coding and compressing sound and pictures, but it has several important limitations. When the computer s CPU is asked to do the work of a codec (coder/decoder), it has less power to devote to displaying PowerPoint presentations or crunching spreadsheets. The better the picture and sound quality required, the slower normal computing gets. And even the fastest PCs are limited in the compressed image quality they can produce without the help of a hardware codec.

Recent advances from Lucent Technologies and others take advantage of new, faster CPUs (e.g., 600 MHz Pentium III) to produce usable IP-based videoconferencing, while leaving enough processing power to handle routine tasks like word processing and spreadsheet calculations. But even these systems require a hardware codec board to encode higher-quality video. For this reason, systems like Lucent s iCosm are...