Image magnification device and image magnification method

Abstract

A high-definition magnified image is obtained by simple computation. A magnified image is obtained by obtaining a deteriorated image on the basis of an input original image, determining enhancement filters used for individual small areas of the original image using the deteriorated image at least, performing a filtering process by applying the filters thus determined to the individual small areas to achieve enhancement, and interpolating the image for magnification.

1 . An image magnification device, comprising: 
 a deterioration unit that obtains a deteriorated image on the basis of an input original image;    a filter determining unit that determines enhancement filters for individual small areas of the original image using the deteriorated image at least;    an enhancement unit that performs a filtering process by applying the filters determined by the filter determining unit to the individual small areas to obtain an enhanced image; and    a magnification unit that interpolates the image to obtain a magnified image.    
   
   
       2 . The image magnification device according to  claim 1 , wherein the filter determining unit obtains a characteristic of each small area from the deteriorated image and determines an enhanced filter associated with the characteristic as an enhancement filter used for the small area.  
   
   
       3 . The image magnification device according to  claim 1 , wherein results are obtained from filtering of each small area of the deteriorated image with a previously prepared plurality of enhancement filters, and on the basis of the results, the filter determining unit determines for each small area which enhancement filter is to be used.  
   
   
       4 . The image magnification device according to  claim 1 , wherein results are obtained from filtering of each small area of the deteriorated image with a plurality of enhancement filters while changing distribution of filter coefficients of the plurality of enhancement filters which provide different degrees of enhancement, and on the basis of the results, the filter determining unit determines for each small area which enhancement filter is to be used.  
   
   
       5 . An image magnification method which is executed by a computer, comprising the steps of: 
 obtaining a deteriorated image on the basis of an input original image;    determining enhancement filters for individual small areas of the original image using the deteriorated image at least;    performing a filtering process by applying the filters determined by the step of determining to the individual small areas to obtain an enhanced image; and    interpolating the image to obtain a magnified image.    
   
   
       6 . The image magnification method according to  claim 5 , wherein the step of determining the enhancement filters includes obtaining a characteristic of each small area from the deteriorated image and determining an enhanced filter associated with the characteristic as an enhancement filter used for the small area.  
   
   
       7 . The image magnification method according to  claim 5 , wherein the step of determining enhancement filters includes obtaining results from filtering of each small area of the deteriorated image with a previously prepared plurality of enhancement filters, and on the basis of the results, determining for each small area which enhancement filter is to be used.  
   
   
       8 . The image magnification method according to  claim 5 , wherein the step of determining enhancement filters includes obtaining results from filtering of each small area of the deteriorated image with a plurality of enhancement filters while changing distribution of filter coefficients of the plurality of enhancement filters which provide different degrees of enhancement, and on the basis of the results, determining for each small area which enhancement filter is to be used.  
   
   
       9 . A storage medium which stores an image magnification program for causing a computer to execute the steps of: 
 obtaining a deteriorated image on the basis of an input original image;    determining enhancement filters for individual small areas of the original image using the deteriorated image at least;    performing a filtering process by applying the filters determined by the step of determining to the individual small areas to obtain an enhanced image; and    interpolating the image to obtain a magnified image.    
   
   
       10 . A storage medium according to  claim 9 , wherein the step of determining the enhancement filters includes obtaining a characteristic of each small area from the deteriorated image and determining an enhanced filter associated with the characteristic as an enhancement filter used for the small area.  
   
   
       11 . A storage medium according to  claim 9 , wherein the step of determining enhancement filters includes obtaining results from filtering of each small area of the deteriorated image with a previously prepared plurality of enhancement filters, and on the basis of the results, determining for each small area which enhancement filter is to be used.  
   
   
       12 . A storage medium according to  claim 9 , wherein the step of determining enhancement filters includes obtaining results from filtering of each small area of the deteriorated image with a plurality of enhancement filters while changing distribution of filter coefficients of the plurality of enhancement filters which provide different degrees of enhancement, and on the basis of the results, determining for each small area which enhancement filter is to be used.