Synthesis filter for MPEG-2 audio decoder
US5812979A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 1996 |
| Grant date | Sep 22, 1998 |
| Priority date | — |
| Expiry date | Sep 23, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/665
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A synthesis filter for an MPEG-2 audio decoder comprising a first coefficient ROM for storing cosine matrix coefficients therein, a first queue memory for storing subband data therein, a first MAC unit for performing a matrixing operation by multiplying the subband data stored in the first queue memory by the cosine matrix coefficients stored in the first coefficient ROM, a second queue memory for storing output data from the first MAC unit therein, a third queue memory being copied with the contents of the second queue memory, a second coefficient ROM for storing window coefficients therein, a second MAC unit for synthesizing the contents copied to the third queue memory with the window coefficients stored in the second coefficient ROM to produce audio data, an FIFO memory for storing the audio data from the second MAC unit therein, a D/A converter for converting the audio data stored in the FIFO memory into an analog audio signal and outputting the converted analog audio signal to a speaker, and a controller for controlling multiplication/accumulation operations of the first and second MAC units.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.