Patent · US Expired

Digital copying machine, image reading device used in said digital copying machine, and image processing method used in these devices

US5969828A · kind A · utility

12Cited by
4References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 10, 1997
Grant dateOct 19, 1999
Priority date
Expiry dateOct 10, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/41
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

In the image data processing of the digital copying machine (M), number of blocks Bn of image data in auxiliary scanning direction is set to the number of expanders (30, 31) Dn times a natural number N (N.times.Dn). This configuration makes it possible to utilize the (30, 31) expanders efficiently regardless of whether the image is to be rotated by 90.degree. or not when expanding compressed image data and printing the image. Thus such a situation that the expanders (30, 31) are forced to suspend the expanding operation does not occur, making it possible to start printing earlier and improve the printing speed. In the image reader 1 of the digital copying machine (M), when dividing image data corresponding to original document into a plurality of blocks and compressing the image data in the unit of block, length of the original document in the auxiliary scanning direction is estimated from width of the original document (size in principal scanning direction). Then by setting the partition of divided blocks based on the estimated document length, the image data can be compressed without waiting for the end of image data input for each block, not doing over the compression process ev…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.