Image Processing Method and Program

Abstract

The present application provides an image processing method of obtaining a clear image from a blurred image which includes the steps of converting an array of image data from a two dimension into a one-dimensional vector, the image data storing pixel values of the blurred image; converting all of two-dimensional matrix operations acting on the one-dimensional vector into an image filtering for the image data of the blurred image, and calculating values of statistic parameters necessary for calculation of a cost function estimating the clear image and a gradient vector of the cost function; and obtaining, by using the gradient vector being calculated, image data of the clear image by a numerical optimization method which calculates the image data of the clear image by using only the gradient vector such that a value of the cost function becomes maximum or minimum.

1 . An image processing method of obtaining a clear image from a blurred image, comprising:
 converting an array of image data from a two dimension into a one-dimensional vector, the image data storing pixel values of the blurred image;   converting all of two-dimensional matrix operations acting on the one-dimensional vector into an image filtering for the image data of the blurred image, and calculating values of statistic parameters necessary for calculation of a cost function estimating the clear image and a gradient vector of the cost function; and   obtaining, by using the gradient vector being calculated, image data of the clear image by a numerical optimization method which calculates the image data of the clear image by using only the gradient vector such that a value of the cost function becomes maximum or minimum.   
     
     
         2 . The image processing method according to  claim 1 , wherein
 the converting into the one-dimensional vector is performed after adding plurality of new pixels having same pixel values as pixels of an image being adjacent and arraying adjacent to an outer circumference of the image.   
     
     
         3 . The image processing method according to  claim 1 , wherein
 the process of obtaining the image data of the clear image by the numerical optimization method is performed plurality of times.   
     
     
         4 . The image processing method according to  claim 1 , wherein
 one of a conjugate gradient method and a steepest descent method is used as the numerical optimization method.   
     
     
         5 . The image processing method according to  claim 1 , wherein
 the blurred image is an image obtained by smoothing.   
     
     
         6 . The image processing method according to  claim 1 , wherein
 the blurred image is an image obtained when a lens becomes out of focus.   
     
     
         7 . The image processing method according to  claim 1 , wherein
 the blurred image is an image obtained by enlarging a low resolution image by using an enlargement factor greater than 1.   
     
     
         8 . A non-transitory computer readable medium storing a program causing a computer to execute the respective processes of the image processing method according to  claim 1 .