Text image data compression system
US5056154A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 1989 |
| Grant date | Oct 8, 1991 |
| Priority date | — |
| Expiry date | Nov 6, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T9/005
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A text image data compression system for compressing image data having pixels each being expressed by N bit data which varies from a maximum value to a minimum value, includes a circuit for replacing the maximum value N bit data with a first symbol "3" followed by N-1 bit common data "*" and the minimum value N bit data with a second symbol "2" followed by N-1 bit common data "*". Also provided is a circuit for making a symbol alignment such that the most significant symbols are collected and are aligned from the first row to the bottom row, the second significant symbols are collected and are aligned from the first row to the bottom row, kth significant symbols are collected and are aligned from the first row to the bottom row, in which k is between three and N-1, and the least significant symbols are collected and are aligned from the first row to the bottom row, and that all of said common symbols "*" are removed; and a circuit for detecting run lengths in the symbol alignment to produce run lengths of four different symbols "3", "2", "1" and "0".
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.