Tone converting device, image processing apparatus, printing apparatus, tone converting method, and program

摘要

A tone converting device to convert an image density signal having m-valued tone into an image density signal having binary tone, m being a natural number, is provided. The tone converting device includes an input signal accumulating-and-adding unit to accumulate and add sequentially input m-valued image density signals so as to generate a first cumulative sum; an output signal accumulating-and-adding unit to accumulate and add binary image density signals as converted output so as to generate a second cumulative sum; and an output tone setting unit to set a smaller value among two values to an output conversion value when the first cumulative sum is equal to the second cumulative sum or when the second cumulative sum is larger than the first cumulative sum, and to set a larger value among the two values to the output conversion value when the second cumulative sum is smaller than the first cumulative sum.