Efficient system and method for converting between different transform-domain signal representations
US6963842B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 5, 2001 |
| Grant date | Nov 8, 2005 |
| Priority date | — |
| Expiry date | Apr 11, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/0212
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A memory-efficient system converting a signal from a first transform domain to a second transform domain. The system includes a first mechanism that obtains an input signal expressed via a first transform-domain signal representation. A second mechanism expresses the input signal via a second transform-domain signal representation without intermediate time-domain conversion. In the specific embodiment, the input signal is a Modified Discrete Cosine Transform (MDCT) signal. The second transform-domain signal representation is a Discrete Fourier Transform (DFT) signal. The second mechanism further includes a third mechanism that combines effects of an inverse MDCT, a synthesis window function, and an analysis window function, and provides a first signal in response thereto. A fourth mechanism converts the MDCT signal to the DFT signal based on the first signal. In a more specific embodiment, the synthesis window function is an MDCT synthesis window function, while the analysis window function is a DFT analysis window function. The fourth mechanism includes a mechanism for performing a fast transform on the MDCT signal and providing a first transformed signal in response thereto. The …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.