Discrete wavelet transform unit and method for adaptively encoding still image based on energy of each block
US7397957B2 · kind B2 · utility
3Cited by
15References
32Claims
0Family size
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Key dates
| Filing date | Apr 14, 2004 |
| Grant date | Jul 8, 2008 |
| Priority date | — |
| Expiry date | Jul 5, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/63
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed is a discrete wavelet transform (DWT) unit for encoding and decoding still images based on the energy of each block. The DWT unit includes an energy calculating section for calculating energy of an input image in unit of a block having a predetermined number of pixels, an image decomposing section for performing three-level decomposition of the image of the block by decomposing a band at which a low frequency component is distributed three times, and a coefficient substituting section for substituting 0 (zero) for bands at which a high frequency component is distributed among the three-level decomposed bands.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.