| 摘要 |
A method for color image reproduction that includes an image that is defined by a plurality of pixels. A first array of digital values representing the density and placement of the continuous tone colors contained in each pixel of said image is generated. The first array of digital values is processed so as to derive a separate array of digital multi-level color values representing the density and placement of each color for each of the pixels in the image. The processing generates levels and percentage of ink placements for each level change. In one embodiment, the level and percentage of placement within a level change for each of the pixels is derived using an error diffusion method. The error diffusion method includes digitally processing a separate entry array for each multi-level color value so that for each pixel a separate error diffusion array is generated for a plurality of surrounding pixels. The calculations continue on each error diffusion array so as to assign a weight value to each of the plurality of surrounding pixels. The weight values are dependent upon the relative position of said surrounding pixels of which the error diffusion array was determined. The error diffusion processing use the weight values and the error diffusion array to calculate an output array for each pixel that defines the level and the background of a corresponding pixel. In an alternate embodiment, the separate array of digital values representing the density and placement of each multi-level color value for each of the pixels in the image are processed using a half-tone threshold array to create an output array for each pixel which defines the levels and background level. In addition, in one embodiment, the inventive method is capable of limiting the number of sublevels that will be printed thereby allowing the user to control the output, including the amount of ink that is placed on the media. An output array is then produced for each of the colors in the color image.
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