In processing to thicken a white thin line, the application range thereof is controlled to as to prevent a white thin line not intended by a user from being thickened. The thickening processing is performed for a line that has a density less than or equal to a predetermined density and includes a pixel having attribute information of a drawing object; and not performed for a line that has a density less than or equal to the predetermined density and includes a pixel not having attribute information of the drawing object.

Certain examples described herein relate to the halftoning of a color image. In one example, a set of clusters are determined based on the color image. A set of edges are also detected in the color images. Clusters within these edges are then merged. A set of screens for halftoning are assigned to the set of clusters. This assignment is based on color property metrics for the set of clusters. The color image is halftoned using the set of screens assigned to the merged clusters.

A graphical object processor has a single filter. The filter includes a program for constructing a pipeline consisted of a plurality of stages based on a print ticket. In one or more of the plurality of stages, a content box of print-target data is modified. When the content box is modified, commands respectively indicating affine transformation matrices are generated. The commands are pushed into a command stack. The pushed commands are used for modification of a visual element. Specifically, the affine transformation matrices are multiplied and thereby an integrated transformation matrix is generated. The visual element is modified by multiplying an affine transformation matrix of the visual element by the integrated transformation matrix.

An image processing apparatus includes an acquisition unit that acquires N-valued image data corresponding to an image including at least one object, and edge data indicating an edge area of the object, an image processing unit that generates M-valued (N>M2) quantized data where each of a plurality of pixels is associated with one of a value indicating that no dot is to be recorded and a value indicating that a dot is to be recorded, based on the acquired image data, using an image processing parameter, and a changing unit that changes at least one pixel among pixels that indicate the edge area of the object in the edge data and have the value indicating that no dot is to be recorded in the quantized data so that the at least one pixel has the value indicating that the dot is to be recorded.

In an example, a method is described that includes dividing an input image into a plurality of strips, where each strip is smaller than a whole of the input image. A plurality of binary images is then generated, where each of the binary images corresponds to one of the strips. Connected component labeling is performed on the binary images, one binary image at a time. An object map for the input image is then generated based on the results of the connected component labeling.

A graphical object processor has a single filter. The filter includes a program for constructing a pipeline consisted of a plurality of stages based on a print ticket. In one or more of the plurality of stages, a content box of print-target data is modified. When the content box is modified, commands respectively indicating affine transformation matrices are generated. The commands are pushed into a command stack. The pushed commands are used for modification of a visual element. Specifically, the affine transformation matrices are multiplied and thereby an integrated transformation matrix is generated. The visual element is modified by multiplying an affine transformation matrix of the visual element by the integrated transformation matrix.

Apparatus and methods for printing multi-level and multi-color digital image are disclosed herein. In some embodiments, first and second level AM half-tone screens are respectively applied to first and second multi-level color-components of the multi-level and multi-color input digital image to respectively generate first and second target binary images. The first and second target binary images are printed respectively using first and second inks (e.g. of different colors) onto a common surface. Specific properties of the AM half-tone screens as well as techniques for producing the AM half-tone screens are disclosed herein. In some embodiments, the techniques overcome objectionable textures derived from rounding errors in divisional of conventional AM supercells.

A method for improving the print quality of graphic elements, in particular vectorized letter graphics, in PDF documents in the prepress stage of a printing process by using a computer, includes analyzing the page content of the PDF document by using the computer and saving the page content in a suitable data structure, searching the data structure for graphic elements, in particular letter graphics, that fulfill specific predefined criteria relating to an evaluation of the height and width of the graphic paths of graphic elements that are present in the PDF document, by using the computer, converting the selected graphic elements into image masks by rendering the selected graphic elements on the computer and substituting the generated image masks for the originally selected graphic elements in the PDF document by using the computer. The PDF document with the generated image masks are printed on a printing machine.

In an example, an apparatus is described that includes a color conversion module an a visual noise module. The color conversion module converts page description language describing an image into rasterized image data. The visual noise module then recalculates pixel values in an area of flat tint detected in the rasterized image data to introduce visual noise in the area of flat tint.

An image processing apparatus that converts image data of a first resolution into image data of a second resolution lower than the first resolution. The image processing apparatus determines a small dot that is included in the image data of the first resolution and matches a first small dot pattern and performs conversion from the first resolution to the second resolution by switching a method of generating resolution-converted image data based on a result of the determination.