On the standard deviation in charge-coupled device cameras: A variogram-based technique for nonuniform images

Abstract

When estimating the standard deviation of a magnitude with spatial dependence, it is necessary to carry out several measurements at every location where the magnitude is estimated. However, in image applications the standard deviation is commonly measured by means of only one high-uniform image. This procedure tends to increase the standard deviation due to spatial nonuniformity of the image. In this work we propose a new technique based on the variogram, which is a function that measures the spatial correlation of the image, that can be employed to accurately estimate the standard deviation of nonuniform images obtained by charge-coupled device cameras.