Imaging processing apparatus, image processing system and method for processing image

Abstract

According to one embodiment, an image processing apparatus includes an image block generator, a pixel extractor, a correction parameter calculator and a corrector. The image block generator enlarges an image block including a plurality of pixels to generate an enlarged image block. The pixel extractor extracts a maximum pixel with a maximum pixel value and a minimum pixel with a minimum pixel value from the image block. The correction parameter calculator calculates a correction parameter including a first difference and a second difference. The first difference is an absolute value of a difference between a sample pixel value of a sample pixel to be corrected in the enlarged image block and the maximum pixel value. The second difference is an absolute value of a difference between the sample pixel value and the minimum pixel value. The corrector corrects the enlarged image block using the correction parameter.

1 . An image processing apparatus comprising:
 an image block generator configured to enlarge an image block comprising a plurality of pixels to generate an enlarged image block;   a pixel extractor configured to extract a maximum pixel with a maximum pixel value and a minimum pixel with a minimum pixel value from the image block;   a correction parameter calculator configured to calculate a correction parameter comprising a first difference and a second difference, the first difference being an absolute value of a difference between a sample pixel value of a sample pixel to be corrected in the enlarged image block and the maximum pixel value, the second difference being an absolute value of a difference between the sample pixel value and the minimum pixel value in such a manner that a first pixel with a pixel value closer to the maximum pixel value is corrected in the direction of the maximum pixel, a second pixel with a pixel value closer to the minimum pixel is corrected in the direction of the minimum pixel and a third pixel with a pixel value closer to the median between the maximum pixel value and the minimum pixel value is not corrected; and   a corrector configured to correct the enlarged image block using the correction parameter.   
     
     
         2 . The apparatus of  claim 1 , wherein the pixel extractor determines an objective area comprising an objective pixel to be extracted in the image block, changes a pixel value of the objective pixel by a tap filter, and extract the maximum pixel and the minimum pixel from the objective area. 
     
     
         3 . The apparatus of  claim 1 , wherein the pixel extractor divides the image block into an edge area and a smooth area based on degree of characteristic of the image block, extracts a first maximum pixel comprising the maximum pixel value and a first minimum pixel comprising the minimum pixel value in the edge area, and extracts a second maximum pixel comprising the maximum pixel value and a second minimum pixel comprising the minimum pixel value in the smooth area. 
     
     
         4 . The apparatus of  claim 3 , wherein when at least one of a pixel value of the second maximum pixel and a pixel value of the second minimum pixel is out of a predetermined range, the pixel extractor extracts at least one of the second maximum pixel and the second minimum pixel from the objective area to which an area comprising at least one of the second maximum pixel and the second minimum pixel is, at least one of the extracted second maximum pixel and the extracted second minimum pixel with pixel values in the predetermined range. 
     
     
         5 . The apparatus of  claim 1 , wherein when the corrected enlarged image block comprises a pixel with a corrected pixel value out of a predetermined range, the corrector changes the corrected pixel value into at least one of the maximum pixel value and the minimum pixel value. 
     
     
         6 . An image processing system comprising:
 an image block generator configured to enlarge an image block comprising a plurality of pixels to generate an enlarged image block;   a pixel extractor configured to extract a maximum pixel with a maximum pixel value and a minimum pixel with a minimum pixel value from the image block;   a correction parameter calculator configured to calculate a correction parameter comprising a first difference and a second difference, the first difference being an absolute value of a difference between a sample pixel value of a sample pixel to be corrected in the enlarged image block and the maximum pixel value, the second difference being an absolute value of a difference between the sample pixel value and the minimum pixel value in such a manner that a first pixel with a pixel value closer to the maximum pixel value is corrected in the direction of the maximum pixel, a second pixel with a pixel value closer to the minimum pixel is corrected in the direction of the minimum pixel and a third pixel with a pixel value closer to the median between the maximum pixel value and the minimum pixel value is not corrected;   a corrector configured to correct the enlarged image block using the correction parameter; and   a display configured to display an image based on the corrected enlarged image block.   
     
     
         7 . The system of  claim 6 , further comprising:
 an imaging apparatus configured to pick up the image of an object to generate image data comprising a plurality of pixels; and   a video decoder configured to decode the image data to generate the image block.   
     
     
         8 . The system of  claim 6 , further comprising:
 a memory configured to store image data; and   a video decoder configured to decode the image data to generate the image block.   
     
     
         9 . The system of  claim 6 , further comprising:
 a communicator apparatus configured to receive image data via a network; and   a video decoder configured to decode the image data to generate the image block.   
     
     
         10 . The system of  claim 6 , wherein the pixel extractor determines an objective area comprising an objective pixel to be extracted in the image block, applies a tap filter to the objective area to change a pixel value of the objective pixel, and extract the maximum pixel and the minimum pixel from the objective area. 
     
     
         11 . The system of  claim 6 , wherein the pixel extractor divides the image block into an edge area and a smooth area based on degree of characteristic of the image block, extracts a first maximum pixel comprising the maximum pixel and a first minimum pixel comprising the minimum pixel in the edge area, and extracts a second maximum pixel comprising the maximum pixel and a second minimum pixel comprising the minimum pixel in the smooth area. 
     
     
         12 . The system of  claim 11 , wherein when at least one of the pixel extractor extracts a pixel value of the second maximum pixel and a pixel value of the second minimum pixel is out of a predetermined range, the pixel extractor extracts at least one of the second maximum pixel and the second minimum pixel from the objective area to which an area comprising at least one of the second maximum pixel and the second minimum pixel is, at least one of the extracted second maximum pixel and the extracted second minimum pixel with pixel values in the range. 
     
     
         13 . A method for processing image, the method comprising:
 enlarging an image block comprising a plurality of pixels to generate an enlarged image block;   extracting a maximum pixel with a maximum pixel value and a minimum pixel with a minimum pixel value from the image block;   calculating a correction parameter comprising a first difference and a second difference, the first difference being an absolute value of a difference between a sample pixel value of a sample pixel to be corrected in the enlarged image block and the maximum pixel value, the second difference being an absolute value of a difference between the sample pixel value and the minimum pixel value in such a manner that a first pixel with a pixel value closer to the maximum pixel value is corrected in the direction of the maximum pixel, a second pixel with a pixel value closer to the minimum pixel is corrected in the direction of the minimum pixel and a third pixel with a pixel value closer to the median between the maximum pixel value and the minimum pixel value is not corrected; and   correcting the enlarged image block using the correction parameter.