Method and apparatus for improving image quality

Abstract

A method (and apparatus) of improving an image quality of a video signal which is supplied on a frame-by-frame basis, includes extracting high frequency components associated with a video signal of an n-th frame (where n is a natural number), and adding the extracted high frequency components to a video signal of an (n+m)th frame (where m is a natural number).

1 . A method of improving an image quality of a video signal which is supplied on a frame-by-frame basis, comprising: 
 extracting high frequency components associated with a video signal of an n-th frame, where n is a natural number; and    adding the extracted high frequency components to a video signal of an (n+m)th frame, where m is a natural number.    
   
   
       2 . The image quality improving method according to  claim 1 , further comprising: 
 extracting low frequency components from the video signal of the n-th frame; and    subtracting the extracted low frequency components from the video signal of the (n+m)th frame to produce the high frequency components.    
   
   
       3 . The image quality improving method according to  claim 2 , further comprising: 
 extracting the low frequency components from the video signal of the n-th frame in at least one of a horizontal direction of an image displayed by the video signal, and a vertical direction of an image displayed by the video signal.    
   
   
       4 . The image quality improving method according to  claim 1 , further comprising: 
 extracting low frequency components from the video signal of the n-th frame; and    subtracting the extracted low frequency components from the video signal of the n-th frame to produce the high frequency components.    
   
   
       5 . The image quality improving method according to  claim 4 , further comprising: 
 extracting the low frequency components from the video signal of the n-th frame in at least one of a horizontal direction of an image displayed by the video signal, and a vertical direction of an image displayed by the video signal.    
   
   
       6 . An apparatus for improving an image quality of an input video signal which is supplied on a frame-by-frame basis, comprising: 
 a high frequency component extractor that extracts high frequency components associated with a video signal of an n-th frame, where n is a natural number; and    an adder that adds the high frequency components extracted by said high frequency component extractor to a video signal of an (n+m)th frame, where m is a natural number.    
   
   
       7 . The image quality improving apparatus according to  claim 6 , wherein said high frequency component extractor comprises: 
 a low frequency component extractor that extracts low frequency components from the video signal of the n-th frame; and    a subtractor that subtracts the low frequency components extracted by said low frequency component extractor from the input video signal to extract the high frequency components.    
   
   
       8 . The image quality improving apparatus according to  claim 7 , wherein said subtractor subtracts the low frequency components extracted by said low frequency component extractor from the video signal of the (n+m)th frame to extract the high frequency components.  
   
   
       9 . The image quality improving apparatus according to  claim 8 , wherein said low frequency component extractor comprises: 
 a frame memory to delay the input video signal supplied on a frame-by-frame basis in units of frames; and    a low-pass filter that extracts low frequency components from the video signal delayed by said frame memory.    
   
   
       10 . The image quality improving apparatus according to  claim 9 , wherein said low-pass filter extracts the low frequency components from the video signal delayed by said frame memory in at least one of a horizontal direction of an image displayed by the video signal, and a vertical direction of an image displayed by the video signal.  
   
   
       11 . The image quality improving apparatus according to  claim 8 , wherein said low frequency component extractor comprises: 
 a horizontal low-pass filter that extracts low frequency components of the input video signal supplied on a frame-by-frame basis in a horizontal direction of an image displayed by the video signal;    a down-sampler that reduces the number of samples in a video signal that has the low frequency components in the horizontal direction that have been extracted by said horizontal low-pass filter;    a frame memory to delay the video signal down-sampled by said down-sampler in units of frames;    a vertical low-pass filter that extracts low frequency components from the video signal delayed by said frame memory in a vertical direction of the displayed image; and    an up-sampler that returns the number of samples in a video signal that has the low frequency components in the vertical direction that have been extracted by said vertical low-pass filter to the original number of samples.    
   
   
       12 . The image quality improving apparatus according to  claim 8 , wherein said low frequency component extractor comprises: 
 a first infinite impulse response (IIR) filter that extracts low frequency components from the input video signal supplied on a frame-by-frame basis in at least one of a horizontal direction of the input video signal, and a vertical direction of the input video signal;    a first frame inverter that inverts a time-axis of a video signal that has the low frequency components that have been extracted by said first IIR filter;    a second IIR filter that extracts low frequency components from the video signal, the time-axis of which has been inverted by said first frame inverter, in at least one of a horizontal direction of the video signal, and a vertical direction of the video signal; and    a second frame inverter that inverts the time-axis of a video signal that has the low frequency components that have been extracted by said second IIR filter.    
   
   
       13 . The image quality improving apparatus according to  claim 7 , wherein said subtractor subtracts the low frequency components extracted by said low frequency component extractor from the video signal of the n-th frame to extract the high frequency components.  
   
   
       14 . The image quality improving apparatus according to  claim 13 , wherein said low frequency component extractor extracts the low frequency components from the video signal of the n-th frame in at least one of a horizontal direction of an image displayed by the video signal, and a vertical direction of an image displayed by the video signal.  
   
   
       15 . The image quality improving apparatus according to  claim 6 , further comprising: 
 a multiplier that adjusts the amplitude of a high frequency component signal supplied from said high frequency component extractor.    
   
   
       16 . A display apparatus comprising: 
 the image quality improving apparatus according to  claim 6;     a display device; and    a driving circuit that drives said display device based on a video signal supplied from said image quality improving apparatus.    
   
   
       17 . A method of improving an image quality of a video signal which is supplied on a frame-by-frame basis, comprising the steps of: 
 a step for extracting high frequency components associated with a video signal of an n-th frame, where n is a natural number; and    a step for adding the extracted high frequency components to a video signal of an (n+m)th frame, where m is a natural number.    
   
   
       18 . An apparatus for improving an image quality of an input video signal which is supplied on a frame-by-frame basis, comprising: 
 means for extracting high frequency components associated with a video signal of an n-th frame, where n is a natural number; and    means for adding the high frequency components extracted by said high frequency component extractor to a video signal of an (n+m)th frame, where m is a natural number.