Patent ID: 7050647

Claim:
A median filter for extracting a pixel data value corresponding to the median value from pixel data in a window of a predetermined size, comprising: sorting means for receiving pixel data along each column in the window and sequentially sorting each data string in respective columns; a shift register for sequentially storing the sorted data string, which is sorted by said sorting means, in each stage of the shift register; first merging means for merging the sorted data strings in a plurality of stages of the shift register and generating a sorted data string; and second merging means for merging the sorted data string, which is generated by said first merging means, with a new sorted data string in the shift register and generating a sorted data string, wherein, all the data strings sorted by said sorting means are merged by said first and second merging means and sorted to generate a data string, and pixel data at the median rank of the generated data string is output as the median value of the pixel data in the window.