Method for compressing audio signal using wavelet packet transform and apparatus thereof
US7225123B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 19, 2003 |
| Grant date | May 29, 2007 |
| Priority date | — |
| Expiry date | Jun 10, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/0216
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An audio compression method using wavelet packet transform (WPT) in MPEG1 layer 3 (hereinafter referred to as “MP3”) and a system thereof are provided. The method comprises calculating perceptual energy by analyzing audio samples which are input based on a psychoacoustic model; according to comparison of the level of the calculated perceptual energy with a threshold, selectively determining a modified DCT (MDCT) processing window and a wavelet packet transform (WPT) processing window; by processing audio samples corresponding to the scopes of the determined windows in the MDCT and WPT, converting the audio samples into data on frequency domains; and quantizing the processed data on the frequency domains according to the number of assigned bits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.