Patent ID: 6373990
Filing Date: 2002-04-16
Classification: G06T,H04N

Abstract:
An image processing apparatus comprising:image input means for entering multilevel image data in which one pixel is represented by n bits, wherein the multilevel image data is luminance data; processing means for processing the multilevel image data in such a manner that each pixel of the multilevel image data is subjected to a two-level or m-level conversion (where mluminance-density converting means for converting the luminance data to density data and supplying the density data to said processing means, wherein said processing means executes two-level or m-level error diffusion processing and makes common use of an arithmetic processing unit and an error buffer for executing both the m-level error diffusion and the two-level error diffusion, and the luminance-density converting means converts the luminance data in such a manner that the density data will have a range of output values of j bits in a case where the two-level conversion processing is processed by said processing means, and converts the luminance data in such a manner that the density data will have a range of output values of k bits (k>j) in a case where the m-level conversion is processed by said processing means.