Image forming apparatus which forms an image based on bit map data
US5923828A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 25, 1997 |
| Grant date | Jul 13, 1999 |
| Priority date | — |
| Expiry date | Feb 25, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K2215/0065
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image forming apparatus which forms an image based on bit map data. A compressing circuit compresses the bit map data to generate compressed data by reversible compression, and the compressed data is then stored in a first storing unit, such as a frame memory. Then, a decompression circuit reads and decompresses the compressed data. The decompressed data can then be stored in a second memory unit, such as a FIFO memory. An amount of data stored in the second memory is detected and based on the amount of data detected, a controller controls reading of the compressed data by the decompression unit. Based on the detected amount of data stored in the second storing unit, the decompression unit can execute a non-reversible decompression operation in which data is omitted prior to being stored in the second storing unit. An image based on the decompression data from the second storing unit is then recorded. The omitted data can also be reintroduced onto a finally recorded image, so that the recorded image fully corresponds to the original image data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.