An image processor sets the dot value to a value for forming a dot in a case where the dot forming condition is satisfied; sets the dot value to a value for forming no dot in a case where the dot forming condition is not satisfied and the target pixel is not the edge pixel; sets the dot value to a value for forming a dot in a case where the dot forming condition is not satisfied and a particular condition is satisfied; and sets a distribution error value to a smaller value than another error value in a case where the dot forming condition is not satisfied and the particular condition is satisfied and thereby the dot value is set to the value for forming a dot.

A correction method for an image forming apparatus including: a light source including light emitting points, a photosensitive member configured to rotate in a first direction, and a deflecting unit configured to deflect light beam emitted from the light source in a second direction orthogonal to the first direction to form scanning lines, the correction method including a correction step of correcting sparseness and denseness of density in the first direction caused by deviation of the scanning lines by moving a predetermined pixel in the first direction in accordance with the deviation, and causing a pixel value of the predetermined pixel to be output in accordance with movement of the predetermined pixel, wherein the correction step corrects the sparseness and denseness of the density based on the deviation of the scanning lines and the pixel value of the pixel, which are adjusted in accordance with an image forming condition.

A method, non-transitory computer readable medium and apparatus for starting a multiple scanline error diffusion method are disclosed. For example, the method includes identifying a pixel for each scanline of a plurality of scanlines, wherein the pixel that is identified in the each scanline of the plurality of scanlines is offset, setting all pixels behind the pixel for the each scanline of the plurality of scanlines that is identified with a white pixel value and starting the multiple scanline error diffusion method.

Image processing transforms input multi-level image data into output image data having a smaller number of levels (the input and output image data represents images formed of cells). The image processing distributes quantization error of a target cell of the image to neighbor cells in proportions determined by a set of weights. The distribution excludes neighbor cells whose data level is less than a threshold value from receiving distributed quantization error, or allows just a fraction of the quantization error to be distributed to such neighbor cells.

An image processing apparatus includes an image processor that performs error diffusion processing by applying an error diffusion matrix to multi-valued image data having pixels two-dimensionally arranged, so as to convert the multi-valued image data into binary image data. The binarization unit applies an error diffusion matrix in which the diffusion coefficient of a pixel diagonal to a focused-on pixel is greater than those of other pixels.

An image processing device which generates a halftone image includes: an image size adjustment unit which adjusts a size of the input image; and a halftone processing unit which performs halftone processing on the input image size-adjusted to generate a halftone image, wherein: the image size adjustment unit adjusts the input image to a same size in two or more printing modes among the plurality of printing modes, and the input image of the same size is subjected to the halftone processing; the unit limits arrangement of dots constituting the halftone image to dot arrangeable places of a selected printing mode among the plurality of printing modes, and performs the halftone processing based on an error diffusion method using an error diffusion coefficient matrix according to the selected printing mode; and the functions performed by the image size adjustment unit and the halftone processing unit are achieved using a computer.

Provided is a method by which an image forming apparatus forms an image, the method including detecting a boundary area in a portion of image data; determining a direction of the boundary area, a dominant color of the boundary area, and an edge intensity of the boundary area; determining enhancement information with respect to the boundary area based on the direction, the dominant color, and the edge intensity; and forming an image with respect to the image data based on the determined enhancement information.

A forming method for forming a three-dimensional object includes a generating step including, based on model data representing the object, generating cross-section data respectively representing cross-sections of the object that are different in position in a cross-section arrangement direction. An executing step includes discharging build materials respectively based on the cross-section data. When at least a portion of the object is to be colored: the cross-section data include colored region data respectively representing cross-sections of a colored region of the object that is to be colored based on a color of a surface of the object; the executing step includes forming the colored region using the build materials based on the colored region data; the model data represents the color of the surface of the object in a multi-level gradation; and each of the colored region data represents a color in a lower level of gradation.

Methods and apparatus of determining a halftone scheme are described. In an example, data representing a three-dimensional object is obtained, the data comprising object model data representing the geometry of the three-dimensional object and object property data representing at least one object property of at least a portion of the object. It is determined if a halftone scheme dependent object property is specified by the object property data and a halftone scheme is determined. Data representing a portion of the object having a halftone scheme dependent object property is associated with a determined halftone scheme.

Systems, apparatuses, and methods may provide for technology to control the printing of halftoning screen signatures for various levels of prints. For example, such prints may include regular edition prints or limited edition prints. During printing, a first halftoning screen is associated with one or more of the regular edition prints and a second halftoning screen is associated with the limited edition print, in some implementations. The second halftoning screen has a spatial frequency that is substantially the same as the first halftoning screen while having a spatial signature different from the first halftoning screen. Additionally, the second halftoning screen further may have spectral properties that are substantially the same as the first halftoning screen. During printing, two different printed copies of an image are formed using the first halftoning screen and the second halftoning screen.