期刊名称：Archiwum Fotogrametrii, Kartografii i Teledetekcji
印刷版ISSN：2083-2214
出版年度：2006
卷号：16
语种：English
出版社：Main Board of Association of Polish Surveyors
摘要：In photogrametric works there are often serial photographs which have different radiometric quality levels. In most cases,radiometric distortion of serial photographs is connected with vignetting. Generally speaking,this phenomenon can be defined as radial radiometric distortion. Removal of this distortion is important,particularly in the process of orthophotomap generation. Radiometric correction assures distribution homogeneity of the color values in an aerial photo. The requirement of execution of this operation is included in the technical guideline entitled “Principles of practices of photo aerial works”. This article briefly describes the mathematical model of radiometric distortion. Selected examples of photographs which need radiometric correction are presented. The changes involve diagrams of digital grey-levels of pixel,correction function and the results of corrections. A model of radial radiometric correction was built in the polar coordinates system. The distributions of color values were determined in the same system. Finally,corrective functions are defined as linear functions,in which the independent variable was the distance from the center of image. Appropriate algorithms were developed in order to conduct experiments,to make radiometric correction and analyses. For this,the author used scanned analog photographs of Aalborg from 2002, which were taken by a LC 0015 camera. The author created the application in Java,in which the presented algorithms were used. Some particular problems of radiometric correlation were solved in the introduced elaboration. Certainly,other cases of corrections (correction of a block of photos which have different overlaps, linear correction in different directions,nonlinear corrections and correction in the chosen area of aerial photo) should be also considered. The problem of radiometric correction has not been solved completely so far. It can be supposed that this subject area will find interest and further research will be conducted.
其他摘要：W pracach fotogrametrycznych mamy do czynienia ze zdjęciami o róŜnej jakości radiometrycznej. Najczęściej występujące zniekształcenia radiometryczne związane są z winietowaniem. Ogólniej moŜna to zjawisko określić jako radialne zniekształcenia radiometryc
关键词：image distortions;vignetting;radiometric distortion;brightness decrease function
