Audio

New Licensable Cores Target Audio

Last week three vendors introduced licensable cores targeting consumer audio applications. In the first of these announcements, MIPS announced the MIPS24KEc, the first core to implement the "DSP ASE" signal-processing instruction-set extensions. (For a discussion of these extensions, see the October 2004 edition of Inside DSP.) Although the MIPS24KEc is not specifically tuned for audio applications, MIPS claims that the addition of the DSP ASE provides a 15%-40% boost in performance across a Read more...

Case Study: Measuring Multimedia Performance

At first glance, measuring processor performance on multimedia applications can seem straightforward. Many multimedia applications are based on published standards and widely available software. For example, MPEG-4 video decompression software is available for most popular processors. Because such software is often readily available, measuring multimedia performance may seem to be a simple matter of checking the processor vendor's published performance data for the relevant software modules Read more...

Khronos Announces Cross-Platform Multimedia API

On July 6, the Khronos Group announced OpenMAX, an application programming interface (API) covering a set of basic functions used in graphics, still image, audi o, and video software. For example, OpenMAX will include API calls for video decompression sub-functions like the inverse discrete cosine transform. OpenMAX is intended to be a cross-platform API, enabling programmers to use the same function calls across a wide range of architectures. According to Khronos, OpenMAX is a response to Read more...

Case Study—Measuring Multimedia Performance

At first glance, measuring processor performance on multimedia applications can seem straightforward. Many multimedia applications are based on published standards and widely available software. For example, MPEG-4 video decompression software is available for most popular processors. Because such software is often readily available, measuring multimedia performance may seem to be a simple matter of checking the processor vendor’s published performance data for the relevant software modules Read more...

Inside DSP on Audio: Ear To The Ground

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. Home Audio Gets Surrounded The major consumer audio applications can be loosely grouped into three categories: Read more...

Inside DSP on Audio: Inside a Modern Digital Audio Product

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. How do manufacturers pack the DSP punch these applications require into small, affordable, and power-efficient systems? A portable audio player, for example, Read more...

Inside DSP on Audio: Digital Audio Technology Guide

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. In this article we'll take a look at key processor options and processor selection criteria for consumer audio products. We'll examine the various Read more...

Inside DSP on Audio: Building Good Audio Software

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. In this Read more...

Inside DSP on Audio: Ubiquitous Digital Audio

In the average American home today you will probably find ten or twenty separate digital clocks. There is one in your computer, of course, but there's probably also one on the stove, one on the VCR, one on the radio, one on your coffee machine, one on your microwave oven—your home is probably infested with them. There's a good reason for this. For products that already include an embedded processor, the addition of clock functionality comes almost for free. Just add an LCD display and a Read more...

Inside DSP: A New Slant—Welcome to InsideDSP

CMP Media and BDTI are pleased to introduce Inside[DSP], an innovative new series of periodic supplements to EE Times. Each Inside[DSP] supplement will focus on the digital signal-processing technology behind a particular end-equipment market. These will include product categories such as consumer audio and video, mobile multimedia devices, automotive signal-processing applications, and communications equipment. “What?” you say, “Another trade publication? Don't these guys understand that I' Read more...