Image compressing apparatus, image compressing method, image decompressing apparatus, image decompressing method, image forming apparatus and recording medium
US8265401B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 24, 2010 |
| Grant date | Sep 11, 2012 |
| Priority date | — |
| Expiry date | Jan 29, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/186
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
When compressing continuous tone bit map image data, the image compression section of the image compressing apparatus segments the continuous tone bit map image data into bit map image data for lossy compression, index image data for lossless compression and bit map image data for lossless compression based on pixel identification information data. The lossy compression section of the image compression section performs lossy compression process according to the JPEG method for the bit map image data for lossy compression, and the first lossless compression section thereof performs lossless compression process according to the JBIG method for the index image data for lossless compression. Furthermore, the second lossless compression section thereof performs lossless compression process according to the JPEG-LS method for the bit map image data for lossless compression.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.