Patent · US Expired

Method of automatic determination of the contrast and brightness of a digital radiographic image

US6718056B1 · kind B1 · utility

7Cited by
6References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 29, 1999
Grant dateApr 6, 2004
Priority date
Expiry dateNov 29, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T2207/30168
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The method comprises a histogram of the radiographed image, i.e., a real histogram, a mathematical model of the image chain and the object obtained by calibration. The mathematical model of the image chain and the object and a set of parameters of acquisition, of the detector, of the positioner and of the object are used to determine two values of gray level, gray min and gray max, delimiting a useful zone and the part below gray min and the part above gray max are suppressed in the real histogram, i.e., a limited histogram. A set of rules is applied to the limited histogram in order to determine the level of brightness (WL) and the contrast (WW) is obtained from the brightness and possibly from one or more parameters selected by the user or fixed a priori.

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