Patent ID: 8773720
Filing Date: 2014-07-08
Classification: G06K,H04N

Abstract:
1. An image processing apparatus comprising: a halftone processing unit configured to perform first halftone processing for input image data having a first number of gradations, generating halftone image data having a second number of gradations smaller than the first number of gradations; a calculation unit configured to calculate quantization error data representing a quantization error generated in the halftone image data owing to the first halftone processing based on the difference between the input image data and the halftone image data; a generation unit configured to perform second halftone processing for the quantization error data calculated by said calculation unit, generating correction data having the second number of gradations for correcting the quantization error generated by the first halftone processing; and a correction unit configured to correct the halftone image data using the correction data generated by said generation unit.