To prevent shifts in the landing positions of ink in edge regions, two adjacent nozzles to which ink is supplied from a common liquid chamber are restricted from simultaneously discharging ink.

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.

A printer driver 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 device includes circuitry to segment an image corresponding to input image data into a black text area including black text and a non-black text area of the image data other than the black text area, perform a first type of color correction on pixel data items in the black text area and a second type of color correction on pixel data items in the non-black text area to generate a processed image, and determine whether or not the image is a color image using the processed image. The second type of color correction is different from the first type of color correction.

Methods and systems for printing clear tagged objects on clear plane are described herein. In an example, the system draws a bounding box for each block of text/graphic objects. Within each bounding box, an occupancy percentage of foreground pixels (tagged as clear objects) is computed against background pixels. If the computed occupancy percentage falls below a defined threshold value, then that text/graphic object is considered for application of dilation. Thus, the device described herein doesn't check the size of the text/graphic objects; rather checks for the occupancy percentage of the text/graphic objects within a bounding box. While constructing the clear plane to support flood clear, the clear values corresponding to the dilated pixels (pixels considered for dilation) will be intelligently modified. In this way, only intended and logically desired text/graphic objects undergo for dilation.

An image processing apparatus includes an output image reading portion that reads an image of a physical document. The physical document includes a desired print image and a line image. The apparatus further includes a line image detecting portion that detects the line image at a predetermined position of the physical document using the image, a line image analyzing portion that determines a line width of the line image, a line-width correction value determining portion that compares the determined line width to a preliminarily set line-width threshold value and determines a line-width correction value based on the comparison, and a line-width correcting portion that performs line width correction on a to be formed line image based on the line-width correction value.

An image processing unit includes a region separation device and a spatial filtering device. The region separation device detects line widths of a manuscript image in which the line widths are different between a vertical line and a horizontal line and determines which of the vertical line or the horizontal line is thinner. The spatial filtering device executes an emphasizing process to make a widening ratio of a thinner line of the vertical line or the horizontal line higher than a widening ratio of the other line.

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.

An image forming apparatus includes a reading unit for sequentially reading, from image data, pieces of pixel data of target pixels along a predetermined direction, a cumulative sum calculation unit for calculating a cumulative sum of gradation values represented by pieces of pixel data of target pixels in a significant image portion read by the reading unit, a determination unit for determining whether the target pixel read by the reading unit is located at a boundary between the significant image portion and a background portion that is a non-significant image portion, and a correction unit for correcting, if the determination unit determines that the target pixel is located at the boundary, a gradation value represented by pixel data of the target pixel by adding a correction amount based on the cumulative sum up to the target pixel calculated by the cumulative sum calculation unit to the gradation value.

An image processing device includes circuitry to segment an image corresponding to input image data into a black text area including black text and a non-black text area of the image data other than the black text area, perform a first type of color correction on pixel data items in the black text area and a second type of color correction on pixel data items in the non-black text area to generate a processed image, and determine whether or not the image is a color image using the processed image. The second type of color correction is different from the first type of color correction.