Digital video is fast becoming the new killer app in signal processing. From surveillance cameras to personal video recorders, from HDTV to the home PC, digital video seems to be everywhere.

This boom in video-capable products is good news for programmable chip vendors.

Texas Instruments announced in January that it has migrated its high-performance fixed-point DSP architecture, the TMS320C64x, to a 90 nanometer process. Three of the existing ’C64x family members—the TMS320C6414, TMS320C6415, and TMS320C6416—are now being fabricated in the 90 nm process and execute at up to 1 GHz. Pricing starts at $189 for the 1 GHz ’C6414 in 10K quantities.

Although the economy appears to be on the mend, established technology companies and venture capitalists alike remain cautious about their investments. They are wary of accepting vendors’ claims about their technology at face value and often turn to outside experts for technical due diligence evaluations to assess and manage risk.

Vendors announcing new signal-processing chips tend to brag about the clock speed of the processor core, just as they did ten years ago. “Look at our hot new processor!” they proclaim. “It’s got lots and lots of Hertz!” But in embedded applications—just as in PC applications—comparing chip performance solely on the basis of core clock speeds never tells the whole story. In fact, it can be downright misleading.

Over 20 years after the compact disc was introduced, we stand on the threshold of a revolution in consumer digital audio: digital audio is becoming one of the most prevalent, exciting technologies in consumer electronics. Enabling this transformation are advances in electronic components, the introduction of new types of digital audio content, and widespread network connectivity.

The last decade has seen consumer audio products from home theater systems to car stereos and portable players go digital. These complicated devices play back compressed audio formats, compensate for room acoustics, and add effects such as reverberation, equalization, and dynamic bass, thanks to the power of digital signal processing.

The digital audio product
Digital audio products are complex systems, comprised of numerous software and hardware subsystems. If you've already read "Anatomy of a Modern Digital Audio Product" you've seen many of these subsystems and how they work together. At the heart of the digital audio system is a microprocessor tasked with rendering audio.

Audio processing functions are usually implemented in software (rather than fixed-function hardware) because software provides flexibility that is not available with hard-wired solutions. For example, compressed audio players are typically required to support a variety of different algorithms such as MPEG-1/Layer 3 (MP3), Windows Media Audio (WMA), and MPEG-AAC. As algorithms evolve, and as new algorithms are introduced, designers of software-based products can upgrade their devices.