Patent · US Expired

Audio decoder circuit and method of operation

US5657454A · kind A · utility

19Cited by
18References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 7, 1995
Grant dateAug 12, 1997
Priority date
Expiry dateJun 7, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N21/4305
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A data processing system (10) is disclosed which comprises a microprocessor host (12) coupled to a decoding system (14). A host interface block (18) receives a bit stream and passes bit stream on to a system decoder block (20). The system decoder block (20) extracts the appropriate data from the bit stream and loads an input buffer (24) or an optional external buffer (26). An audio decoder block (28) retrieves the data from the input buffer (24) and generates scale factor indices, bit per code word values and subband samples which are stored in an arithmetic unit buffer (30). A hardware filter arithmetic unit block (32) retrieves the information from the arithmetic unit buffer (30) and dequantizes, transforms and filters the data to generate PCM output data which is loaded into a PCM buffer (34). The data within the PCM buffer (34) is output by a PCM output block (36) to a digital-to-analog converter (16).

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