Apparatus and method for compensating image being sensed
US6233011A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 18, 1997 |
| Grant date | May 15, 2001 |
| Priority date | — |
| Expiry date | Jun 18, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/401
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus and a method for compensating the gray-scale values of an image scanned by a contact image sensor. The gray-scale compensating apparatus includes: a power supply for providing a fixed level of voltage source, a contact image sensor for scanning an image and outputting image voltages V.sub.IMG of pixels of the image, or scanning a white pixel and outputting the white-level voltage V.sub.P of the white pixel, an analog/digital converter, to receive the fixed voltage from the power supply and the image voltage V.sub.IMG or the white-level voltage V.sub.P, a microprocessor to calculate the average of n white-level values G(x, y), where n is an integer, and the average value G'(x)=(G(x, 0)+G(x, 1)+ . . . +G(x, n-1))/n. The microprocessor also determines the gray-scale values g'(x, y) of the image being compensated by calculating the gray-scale values g(x, y) of the image not compensated in accordance with the value of G'(x).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.