Image processing device
US5987176A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 18, 1996 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | Jun 18, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V10/242
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and device for processing image data for a document includes the steps of reading RGB image data for the document; dividing the document image data into a plurality of blocks including a prescribed pixel matrix; calculating an average value information and a gradation range index for each of the blocks; converting the data for each pixel of each of the blocks into coded image data based on the average value information and the gradation range index so that the coded image data defines each pixel with fewer gradation levels than the original image data; storing in a memory unit the gradation range index and coded data, which were obtained for each block through the converting step; forming letter distribution histograms for a primary scanning direction and a secondary scanning direction for each block determined to belong to a letter image; identifying a direction in which letters of the document are aligned based on a number of change points in the histogram for the primary scanning direction and a number of change points in the histogram for the secondary scanning direction; decoding the coded data for each of the blocks based on the respective average value information a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.