Patent · US Expired

Image correcting apparatus and method, program, storage medium, image reading apparatus, and image forming apparatus

US7477426B2 · kind B2 · utility

20Cited by
7References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 6, 2003
Grant dateJan 13, 2009
Priority date
Expiry dateFeb 19, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T2207/30176
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image correcting apparatus is provided for preventing a degraded image quality which can be caused by a three-dimensional distortion correction made to a scanned image distorted in a trapezoidal shape. Divergent distortion angles α, β of a scanned image are detected using a page contour of a book document which can be found near the upper or lower edge of the scanned image in a main scanning direction. The scanned image is corrected for a divergent distortion based on the divergent distortion angles α, β, followed by a correction of the scanned image for a shape distortion in a sub-scanning direction. In this way, the image quality can be prevented from degradation possibly caused by the three-dimensional distortion correction, if made to such a scanned image distorted in a trapezoidal shape.

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