Abstract: A printing apparatus is provided with a halftone unit performing a halftone process in which a possibility of dot formation is determined for each pixel based on a dot occurrence rate of the pixel constituting image data, and a printing unit forming dots on a recording medium based on the possibility of dot formation. The halftone unit predicts the occurrence of dot overlap in which a plurality of dots overlaps on the printing medium and performs the halftone process based on an evaluation index according to the dot overlap.

Abstract: The present invention provides a dot data processing apparatus for generating data of dots to be formed on a printing medium.

Abstract: Sets of multiple pixels are grouped into pixel groups, and on the basis of tone value distribution in each pixel group, it is decided whether to divide the pixel group. For pixel groups that are not divided, a representative tone value is determined for the pixel group, and for pixel groups that are divided, a representative tone value is determined for each region created by the division. Next, from multilevel halftoning result values derived by multilevel halftoning of the representative tone values, the dot on-off state is determined for each pixel in the pixel groups, and the image is output. At this time, for divided pixel groups, the dot on-off state is determined for each pixel in the regions, based on the multilevel halftoning result value for each region. With multilevel halftoning result values, data creation and transfer can be performed rapidly.

Abstract: The invention provides a dither matrix generating method. This method generates a dither matrix for determining a status of dot formation on each of print pixels of a print image to be formed on a print medium in response to input image data.

Abstract: There is provided a printing apparatus that performs printing while relatively moving a print head in a main scanning direction and a sub scanning direction with respect to a printing medium. The printing apparatus includes: a nozzle row that is installed on the print head and is acquired by aligning a plurality of nozzles, which ejects ink, in the sub scanning direction; a halftone processing unit that performs a halftone process by comparing each threshold value of a dither mask that is formed by a plurality of threshold values with image data that configures an image; and a printing unit that performs printing by controlling ejection of ink from each nozzle of the nozzle row by using a result of the halftone process.

Abstract: This invention provides a method for generating a dither matrix includes: setting an evaluation function for calculating an evaluation value of the dither matrix; providing a dither matrix as an initial state which stores in respective elements each of a plurality of threshold values for deciding presence or absence of dot formation for each pixel according to an input tone value; fixing an element for storing a threshold value in an increasing order from a smaller threshold value while transposing at least one of the plurality of threshold values stored in a part of the elements and a threshold value stored in another part of the elements; and outputting a dither matrix in which elements for storing are fixed with regard to at least part of the plurality of threshold values.

Abstract: An image printing process of the invention first specifies a pixel group tone value of each pixel group consisting of a preset number of multiple pixels and refers to one of correlation maps selected for the pixel group to convert the specified pixel group tone value to a multivalue code. Each of the correlation maps sets multivalue codes in correlation to pixel group tone values. The multivalue codes of all pixel groups constituting an image are output as control data to an image output device. The image output device determines the dot on-off state in respective pixels of each pixel group according to the received control data and actually creates dots on an output medium to complete an output image. Each correlation map referred to for the multivalue coding has a slightly lower tone resolution in a higher tone value area than in a lower tone value area. This arrangement desirably reduces the data volume of the control data, while preventing deterioration of the picture quality.

Abstract: Provided is a printing apparatus that performs printing by moving a print head in main scan directions and sub scan directions relative to a printing medium, including: an input unit that inputs image data constituting an image; a halftone processing unit that converts the input image data to dot data indicating whether or not dots are formed; and a printing unit that performs printing by controlling ejection of ink from the print head based on the result of the halftone process, wherein, in a printing area where an ink duty is in a predetermined range, the printing unit forms dots by forward movement in which the print head relatively moves in one direction of the main scan directions and backward movement in which the print head relatively moves in the direction opposite to the one direction so that a forward-moving dot occurrence ratio that is a ratio of forming the dots by the forward movement and a backward-moving dot occurrence ratio that is a ratio of forming the dots by the backward movement are gradu

Abstract: A plurality of same ink nozzle arrays are provided, and multiple color patches are printed with mutually different dot recording rates respectively using one of the same ink nozzle arrays. Color specification value of the plurality of color patches is measured for each same ink nozzle array. The ink ejection amount error of each same ink nozzle array is determined based on the color specification values of the plurality of color patches for each same ink nozzle array. It is also possible to select among the plurality of color patches a preferable color patch that is closest to a specified reference color patch, and to determine the ink ejection amount error from the dot recording rate of the preferable color patch.

Abstract: A printing apparatus performs printing on a printing medium by moving a print head relative to the printing medium in a main scanning direction, which is a width direction of the printing medium, and a sub-scanning direction that intersects the main scanning direction. The printing apparatus includes a print head that includes a plurality of nozzles configured to eject ink; an acquisition unit that acquires image data; and a dot forming unit that controls the print head so as to eject the ink to form dots corresponding to the image data on the printing medium. When suppression dots, which are dots formed to suppress bleeding, are formed on the printing medium, the dot forming unit controls the print head so that ink corresponding to the suppression dots is ejected from preceding nozzles arranged to eject ink to the printing medium earlier than other nozzles of the plurality of nozzles.

Abstract: A printing method for performing a halftone process on image data representing input tone values of pixels constituting an original image to determine dot formation on each print pixel of a print image to be formed on a print medium, generating dot data representing the determined dot formation, and forming a dot on each of the print pixels for generating the print image according to the dot data. The step of generating the print image includes mutually combining dots formed on print pixels belonging to each of a plurality of pixel groups in a common print area, the plurality of pixel groups having a physical difference at dot formation, the dot formation being performed with respect to each of the pixel groups. A plurality of pixel groups having a physical commonality for the dot formation among the plurality of pixel groups constitute a pixel group family.

Abstract: A one-dimensional LUT has been incapable of color matching. A three-dimensional LUT has been incapable of ensuring a color conversion accuracy enough to reproduce fine changes in color tone on a monochrome image. It has been impossible to suppress a storage capacity for a color conversion table by ensuring the accuracy. There is provided a color conversion table which has a plurality of pieces of reference color image data making correspondence between color data for a first image device and color data for a second image device and comprises a specified total information amount. The color conversion table is used to distribute the reference color image data over a prescribed area in a specified color space. Color data information for each reference color image data is increased more than a specified amount within a limit of the specified total information amount. Further, a color conversion table is created using an original table which highly accurately defines colors in part of the color conversion table.

Abstract: A printing apparatus that prints an image on a print medium using special glossy ink and color ink, the printing apparatus includes a print head including a plurality of special glossy ink nozzles for ejecting the special glossy ink and a plurality of color ink nozzles for ejecting the color ink, a print unit that drives the print head, an obtaining part that obtains image data, a print controller that prints the obtained image data on the print medium by controlling the print head and the print unit. In a case of printing the obtained image data on the special glossy region, the print controller allows a group of the special glossy ink nozzles to be offset from a group of the color ink nozzles in the sub-scanning direction by a predetermined interval, and then performs the printing by ejecting the special glossy ink and the color ink at timings different from each other.

Abstract: This invention provides a printing method of printing on a print medium. The method includes: a dot data generating step of performing a halftone process on image data representing a input tone value of each of pixels constituting an original image, for generating dot data representing a status of dot formation on each of print pixels of a print image to be formed on the print medium; and a print image generating step of forming a dot on each of the print pixels for generating a print image according to the dot data. The print image generating step includes the step of generating the print image by mutually combining dots formed on print pixels belonging to each of a plurality of pixel groups in a common print area. The plurality of pixel groups have a physical difference each other at the dot formation, the dot formation being performed with respect to each of the pixel groups.

Abstract: A representative gradation value is set collectively for each pixel group of several pixels each, and then the representative gradation value undergoes multilevel halftoning. From the multilevel halftoning result value obtained in this way, the presence or absence of dot formation for each pixel is set and the image is output. Also, based on the resolution ratio of the image data input resolution and output resolution, if the pixel group is divided, it is possible to divide the pixel group into suitable sizes for processing, so it is possible to improve the output image quality. Furthermore, even when the pixel group is divided, it is possible to share data for processing, so it is possible to save memory. In addition, it is possible to rapidly output high quality images with a simple process.

Abstract: A printing control method of generating dot data representing a state of dot formation at each pixel in a printed image represented by an given image data, by formation of dots in respective pixels with the at least one colored ink and the quality-enhancing ink available in the print unit. This process includes a processing mode configured to make a quality-enhancing ink dot-recording rate for pixels belonging to a peripheral area lower than the quality-enhancing ink dot-recording rate for pixels belonging to a center area.

Abstract: The purpose of the image processing device is to convert color image data rapidly to data expressed by the dot on/off state. A plurality of adjacent pixels is grouped as a first type of block, and judgment of the dot on/off state performed by suitably using the error diffusion method is performed in block units. The image data after the color conversion used for this judgment is stored once in memory in a compressed state according to the result of edge detection for the block, and when necessary, judgment of the dot on/off state is performed while reading from the memory. The image processing device realizes the judgment rapidly while avoiding making more complex the judgment of the dot on/off state performed in block units. Also, the image data is compressed according to the result of edge detection, so it is possible to read and write rapidly in relation to memory, and furthermore to decompress rapidly.

Abstract: Provided is a printing device which prints an image using a metallic ink and a color ink, the device including: an input unit which inputs image data; a metallic dot formation unit which forms dot concentration dots on a printing medium using the metallic ink; and a color print unit which prints the image indicated by the image data using the color ink on the printing medium on which the dots using the metallic ink are formed.

Abstract: Provided is a printing device which prints an image using a metallic ink and a color ink, the device including: a recording unit which records the metallic ink and the color ink on a printing medium; an input unit which inputs image data; a metallic ink region specifying unit which specifies a region using the metallic ink, in the formation of the image according to the input image data; and a print control unit which prints the image while the color ink is formed relatively larger than that of a region without using the metallic ink, in the region using the metallic ink.

Abstract: A printing apparatus forms dots of special ink and dots of ordinary ink on a printing medium, at least some of the dots of ordinary ink being superimposed on the dots of special ink, or the dots of special ink being superimposed on at least some of the dots of ordinary ink. The printing apparatus includes a head, a transport mechanism, and a print control section. The head has at least one special ink nozzle that ejects the special ink and at least one ordinary ink nozzle that ejects the ordinary ink. The transport mechanism transports the printing medium relative to the head. The print control section controls the head and the transport mechanism, thereby printing an image on the printing medium using the special ink and the ordinary ink.