Patent ID: 7075679
Filing Date: 2006-07-11
Classification: H04N

Abstract:
1. An image processing apparatus for processing multilevel image data, comprising: dividing means for dividing the multilevel image data into pixel blocks each comprising a plurality of pixels; conversion tables each containing a plurality of items of conversion data, each item corresponding to a pixel position in each pixel block obtained by division by said dividing means; conversion means for converting, by referring to said conversion tables, multi-level image data of a pixel of each pixel block obtained by division by said dividing means, into data corresponding to that pixel in the pixel block; and quantization means for quantizing the data corresponding to the pixel in the pixel block produced by said conversion means, wherein each item of the conversion data of each of said conversion tables has been set in such a manner that an average value of the data corresponding to the pixel in the pixel block converted by said conversion means, takes on a value that is based on the multilevel image data within the block.