Image compression apparatus
US7627180B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 2005 |
| Grant date | Dec 1, 2009 |
| Priority date | — |
| Expiry date | Oct 25, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/17
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
To improve the data compression ratio in the data compression/decompression method utilizing the down-sampling process. Image data in a DS area division unit (130) is divided into a plenty of DS areas and DS areas which are not important are converted into contracted data of the block size by down-sampling in a down-sampling unit (131). A relocation unit (132) allocates two or more contracted data in one DS area, inserts file data into the other portion in the DS area, and removes the DS area where no contracted data is allocated, thereby reducing the entire image size. The image data thus contracted is inputted into a JPEG encoder (14) and subjected to a DCT process and a quantization process for each block. When performing restoration, decompression is performed by the JPEG decoder and the original location is restored. As for the contracted data, interpolation is performed to restore the image data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.