Towards object-based audio with Tensilica’s 4th-gen HiFi DSP Architecture IP

January 08, 2015 // By Graham Prophet
Cadence Design Systems’ Tensilica HiFi 4 audio/voice digital signal processor (DSP) intellectual property (IP) core for system-on-chip (SoC) designs claims the highest performance licensable digital signal processing (DSP) core for 32-bit audio/voice processing.

This fourth generation HiFi architecture enables emerging multi-channel object-based audio standards and offers twice the performance versus the HiFi 3 DSP, suiting it for DSP-intensive applications including digital TV, set-top box (STB), Blu-ray Disc and automotive infotainment.

With emerging object-based audio standards, individual sounds become objects that can be placed anywhere in a room. Instead of being mixed at a recording studio, these sounds are mixed on-the-fly at each location where they are played back. The object-based audio system calculates where the sound should emanate from so that it appears in roughly the same space, no matter where speakers are located. This provides a more natural and immersive sound experience, but requires much more DSP processing power. Instead of having to use multiple DSPs to accomplish this, designers can now – Cadence says – get the DSP power they need from one core – the HiFi 4 DSP.

Cadence's Tensilica HiFi 4 DSP is a highly optimised audio/voice processor geared for efficient execution of audio and voice codecs and pre- and post-processing modules as well as other demanding DSP functions in areas such as wireless communications. Its key features include:

- Support for four 32x32-bit multiplier-accumulators (MACs) per cycle with 72-bit accumulators, more than double the performance of other audio DSPs for computationally intensive functions such as fast Fourier transform (FFT) and finite impulse response (FIR)

- Support for eight 32x16-bit MACs per cycle under specified conditions

- Four very long instruction word (VLIW) slot architecture capable of issuing two 64-bit loads per cycle

- Optional vector floating-point unit available, providing up to four single-precision IEEE floating-point MACs per cycle

- Software compatible with the existing HiFi DSP family consisting of over 140 HiFi-optimised audio and voice codecs and audio enhancement software packages.