A system is disclosed. The system at least one physical memory device to store ink estimation logic and one or more processors coupled with the at least one physical memory device, to execute the ink estimation logic to receive one or more gray level histograms, receive one or more halftone designs and generate estimated ink usage data for each of one or more color planes based on the gray level histograms and the halftone designs, wherein each gray level histogram corresponds to one of the one or more color planes, and each halftone design corresponds to one of the one or more color planes.

An liquid ejecting device includes an inkjet head, a scanning driving unit, a storage, an influence degree storage that stores influence degree information, and a control unit. The influence degree information indicates a magnitude of an influence generated at one ejection position by forming dots of the liquid at each of a plurality of ejection positions. The control unit causes other nozzles to eject a larger amount of liquid than at a normal time with respect to at least a part of the ejection position where the liquid is ejected by the other nozzles in the vicinity of an abnormal nozzle at the time of main scan, and selects an ejection position to which the other nozzle ejects a larger amount of the liquid than the normal time based on the influence degree information.

An image processing apparatus generates dot data for printing an image on a printing medium by using dots of different sizes formed by a plurality of nozzles ejecting ink. The image processing apparatus includes a first acquisition unit that acquires dot data specifying printing or non-printing of each of the dots of a plurality of sizes for each pixel, a specification unit that specifies a dot having a strong possibility of being pulled by a dot having landed earlier on the printing medium of dots in the dot data, and a correction unit that corrects a dot specified by the specification unit in the dot data. The image processing apparatus can output an image whose banding is unlikely to be recognized by suppressing image defect due to a change of dots accompanying liquid droplet interference.

To generate a dot pattern whose deterioration of a feeling of granularity, density unevenness, and streaks are unlikely to be recognized visually by more effectively suppressing a change of an overlap of ink droplets on a printing medium. Halftone image data representing a dot pattern of each of two or more kinds of dot different in density reproduction is acquired. Then, in a case where there is a possibility that the contact state between dots changes due to a landed-dot shift of ink in a plurality of specific dots on a condition that dots are formed in accordance with a dot pattern in the halftone image data, the plurality of specific dots is replaced with dots of another kind whose number is less than or equal to that of the plurality of specific dots.

In the case of performing halftone processing using a threshold value matrix, the memory capacity for storing the threshold value matrix is reduced without reducing the image quality of an output image. An image processing apparatus that generates a halftone image by performing halftone processing using a threshold value matrix for each piece of image data of a plurality of color planes corresponding to color materials used for printing processing, and the number of bits of a threshold value in a first threshold value matrix for a color plane whose visibility is relatively low of the plurality of color planes is smaller than the number of bits of a threshold value in a second threshold value matrix for a color plane whose visibility is relatively high of the plurality of color planes.

A look-up table for use in a printing system is created. The printing system prints an input image in a print color space. The look-up table is created by accessing a predetermined look-up table representing a mapping of color values of an input color space to ink-vectors of a print color space; applying a p-by-q halftone threshold matrix to each ink-vector of the predetermined look-up table to generate a p-by-q halftone cell for each ink-vector; and creating a further look-up table which maps, at least a sample of, the color values of input color space to the at least one halftone cell.

A method corrects color density unevenness during a printing operation on an inkjet printing machine having printing nozzles and a computer. The computer modifies the number or size of the drops to be applied to a printing substrate to attain nominal color density values after the processing of a rasterized print image. For different actual tone values, it is determined which target tone value is required to attain a nominal coloration by measuring a test image for every printing nozzle using a color measurement device, and, based thereon, an area coverage-dependent compensation profile is determined and saved on the computer to be applied in the printing operation to calculate the number and size of the drops on the computer.

The disclosed computer-implemented method for performing dithering in non-linear space may include receiving, as an input, a non-linear sRGB-encoded data stream that includes pixel data that is to be displayed on a display screen. The disclosed method may next include generating a dithering mask for the non-linear sRGB-encoded data stream. Still further, the method may include dithering the non-linear sRGB-encoded data stream using the generated dithering mask according to a scalar dithering algorithm or a vector dithering algorithm. The method may also include linearizing the dithered non-linear sRGB-encoded data stream for display on the display screen, and may include providing the linearized RGB-encoded data stream to the display screen for display. Various other methods, systems, and computer-readable media are also disclosed.

A halftone raster image, suitable for rendering a continuous-tone image, which comprises a plurality of regularly tiled spiral dots. Said spiral dots comprise (i) image pixels arranged as a first arc (200) or as a plurality of arcs which together represent a first spiral (100), and (ii) non-image pixels arranged as a second arc (201) or as a plurality of arcs which together represent a second spiral (101), wherein neighbour halftone dots from said plurality of regularly tiled halftone dots represent a double spiral or triple spiral.

An image forming apparatus in which a lighting position of a dot to be firstly generated by screen processing is changed, in a vertical direction, between a first sub-matrix and a second sub-matrix that are included in a dithering matrix and that are adjacent to each other in a lateral direction, in order not to generate a region where no dot exists in a main scanning direction.