Method for performing an inverse cosine transfer function for use with multimedia information
US5754457A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1996 |
| Grant date | May 19, 1998 |
| Priority date | — |
| Expiry date | Mar 5, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F17/147
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for performing an efficient inverse Discrete Fourier Transform (iDCT) is described. Single Instruction Multiple Data (SIMD) instructions are performed concurrently on a plurality of fixed-point data stored in multimedia registers. Operations on fixed-point data can be performed more quickly than corresponding floating-point operations. Throughout the processing of the iDCT, the fixed-point data are carefully shifted to retain the most significant bits and thereby preserve the accuracy of the mulitmedia operations. The iDCT step of transposing the matrix of multimedia data is accomplished while the data is collected to further improve efficiency. Moreover, the step of transposing the matrix of data is broken down into a series of smaller transpositions, depending on the amount of data which the processor can operate on at the same time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.