In order to obtain a smooth gradation reproduction in an image to be formed, an image processing apparatus inputs first data of an image to be formed which includes a color and second data of the image to be formed which does not include the color and has continuous gradation; determines printing material amount data corresponding to the first data; determines, based on the printing material amount data, a dot pattern when forming the image by performing a printing scan a plurality of times on a printing medium; and generates, based on the second data, a switching signal that switches each pixel in accordance with an area ratio of each of a first dot pattern and a second dot pattern.

This disclosure describes examples for generating image content based on both a color value and a dither value that is to be applied. When a color value for the current pixel is the same as the color value for a previous pixel, and a dither value that is to be applied to the current pixel is the same as the dither value that was added to the previous pixel, a display processor may output the output color value for the previous pixel as the output color value for the current pixel.

Measures for use in calibrating a printing device. Historical dot gain linearization lookup table data for the printing device is processed. On the basis of the processed historical dot gain linearization lookup table data, a plurality of input points for a current dot gain linearization lookup table are dynamically determined. The printing device is calibrated according to the dynamically determined current dot gain linearization lookup table.

An image forming apparatus, includes: a conversion unit configured to convert image data based on a conversion condition corresponding to a halftone process type; an image processing unit configured to perform a halftone process to the image data; and a controller configured to control an image forming unit to form a predetermined measurement image on an image carrier, to control the measurement unit to measure the predetermined measurement image, and to generate a predetermined conversion condition corresponding to a predetermined halftone process type based on a measurement result. In a case where the predetermined halftone process type is not performed by the image processing unit from when the predetermined measurement image is formed last time, the controller skips formation of the predetermined measurement image by the image forming unit.

A technique capable of keeping image quality and speeding up a halftone process is provided. An image processing device performs the halftone process on image data in which a pixel has a pixel value conforming to a bit count N. Bits conforming to the bit count N include higher H bits (where H is an integer satisfying an inequality of 1H<N) and lower L bits following the higher H bits (where L is an integer satisfying an inequality of 1LNH). The image processing device includes a first halftone processing unit configured to generate dot data indicative of a formation state of a dot, with respect to a first pixel allowing a determination of a formation state of a dot, based on the higher H bits in the pixel value and higher H bits in a dither mask.

The image processing apparatus of the present invention includes: a first memory configured to store a first threshold value matrix used for halftone processing; a second memory configured to store a second threshold value matrix that is a threshold value matrix used for halftone processing and whose size is larger than the first threshold value matrix; and at least one circuit, the at least one circuit causing processing below: performing halftone processing for image data by using the first threshold value matrix or the second threshold value matrix selected based on attribute information on the image data, and the first threshold value matrix includes threshold values whose maximum number of bits is N and the second threshold value matrix includes threshold values whose maximum number of bits is M (M<N).

The present invention relates to a method of concurrently storing visible grey scale or color information of an image and additional digital information on a data carrier.

A temporary dot pattern at a dot pattern determining target gradation is determined by adding or removing dots as much as the number of dots corresponding to a gradation difference to or from a dot pattern at a gradation at which a dot pattern is already determined, and a dot pattern at a dot pattern determining target gradation is determined by performing a replacement process of replacing dots including some of dots at a dot pattern determined gradation among the dots in the temporary dot pattern with non-dot arrangements. A halftone mask may be constituted by a group of dot patterns at each gradation, or the halftone mask may be constituted by setting a dot pattern for each gradation as a threshold value.

A recording control apparatus for recording a captured image obtains an image to be recorded and analysis information based on a distance to an object in each portion of the image. When causing a recording control unit to execute recording of the image, the recording control apparatus selects, on the basis of a value of each pixel of the image and the analysis information, a dot layout pattern that is used to record each pixel of the image and that indicates a layout of recorded dots included in dots constituting the pixel.

The present invention provides an image processing apparatus which employs a dither method capable of printing a thin line of desired density without any break irrespective of printing conditions. The first threshold changing unit changes part of threshold values in a threshold matrix to generate a first threshold matrix so as to increase the number of dots to be printed in a specific pixel area. The second threshold changing unit changes part of threshold values in the threshold matrix to generate a second threshold matrix such that the number of dots to be printed in a specific pixel area is smaller than the case of changing a threshold value by the first threshold changing unit. A determining unit determines whether a threshold value in the threshold matrix is to be changed by the first threshold changing unit or by the second threshold changing unit.