Patent · US Expired

Verification data encoding method, original image verification method and apparatus, and computer readable medium

US6741722B2 · kind B2 · utility

15Cited by
3References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 26, 2000
Grant dateMay 25, 2004
Priority date
Expiry dateJun 25, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T2201/0083
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

In a verification data encoding method of the invention, a verification data is provided for each of a plurality of pixels of a digital image, in order for determining whether an alteration to the digital image is effected. The verification data is inserted to each of the plurality of pixels of the digital image such that the verification data is invisible. In an original image verification method and apparatus of the invention, a key information is input and a pseudo-random code is provided by taking the pseudo-random code from a sequence of pseudo-random codes initialized by the key information. A verification data is calculated through a predetermined operation based on a pixel value indicated by a predetermined number of bits of the pixel of concern in an input digital image and based on the pseudo-random code. Then, it is determined whether a value of the verification data matches with a value of the pixel of concern in the input digital image, in order to determine whether an alteration to an original digital image is effected, based on a result of the determination.

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