Patent · US Expired

Multi-precision technique for digital audio encoder

US7117053B1 · kind B1 · utility

11Cited by
2References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 26, 1998
Grant dateOct 3, 2006
Priority date
Expiry dateOct 26, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG10L19/16
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

AC-3 is a high quality audio compression format widely used in feature films and, more recently, on Digital Versatile Disks (DVD). For consumer applications the algorithm is usually coded into the firmware of a DSP Processor, which due to cost considerations may be capable of only fixed point arithmetic. Commercial AC-3 Encoders have been successfully implemented on 20-bit and 24-bit word-length processors. However, it is generally assumed that 16-bit processing is incapable of delivering the high fidelity audio, expected from the AC-3 technology. Double precision computation can be utilised on such processors to provide the high quality; but the computational burden of such implementation will be beyond the capacity of the processor to enable real-time operation. Through extensive simulation study of a high quality AC-3 Encoder implementation, a multi-precision technique for each processing block is presented whereby the quality of the encoder on a 16-bit processor matches the single precision 24-bit implementation very closely without excessive additional computational complexity.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.