Abstract: An image-processing method includes: acquiring multi-level tone print data expressed in multi-level tones; determining whether the acquired multi-level tone print data includes line data indicative of a line having a tone; replacing, if the print data includes the line data, the line data with specific line data based on the tone of the line data, the specific line data indicating a specific line having a prescribed tone value and a prescribed structure; and converting the multi-level tone print data to binary data after replacing the line data with the specific line data.

Abstract: A printing control device includes an input image data acquiring unit, a threshold acquiring unit, a determining unit, and a generating unit. The input image data acquiring unit acquires input image data. The input image data includes a plurality of input pixel data. Each input pixel data has an input value. The determining unit determines, for each input pixel data, a difference related value based on a difference between the input value and a threshold value corresponding to the input value. The generating unit generates print data by generating, for each input pixel data, output pixel data based on the difference related value. The output pixel data expresses density corresponding to the difference related value.

Abstract: An image processor includes a first dither data memory storing a first dither matrix, a second dither data memory storing a second dither matrix, a selecting unit selecting one of the first dither matrix and the second dither matrix, and a converting unit converting multi-value image data to binary data by comparing density of the multi-value image data to the threshold value set in corresponding element of the one of the first dither matrix and the second dither matrix selected by the selecting unit. The second dither matrix is configured of a plurality of sub-dither matrices. Each sub-dither matrix has a plurality of elements each assigned with a threshold value in a range from a maximum threshold value to a minimum threshold value. A set of threshold values from the minimum threshold value to a predetermined intermediate threshold value is assigned to elements in corresponding locations of each of the plurality of sub-dither matrices.

Abstract: An image processing device includes a storing unit for storing a dither matrix. The dither matrix has a plurality of dot regions divided into a plurality of sub-matrices. A creating unit is configured to create binary image data by comparing an input value to threshold values of each sub-matrix. The plurality of sub-matrices includes a first sub-matrix having a first threshold value smallest among threshold values in the first sub-matrix; a second sub-matrix having a plurality of threshold values that are smaller than the first threshold value and are arranged adjacent to each other; a third sub-matrix; having a second threshold value largest among threshold values in the third sub-matrix; and a fourth sub-matrix having a plurality of threshold values that are larger than the second threshold value and are arranged adjacent to each other.

Abstract: An image processing device includes an acquiring unit, a calculating unit, a color data determining unit, an appending unit, and a converting unit. The acquiring unit acquires print data. The print data includes a plurality of sets of text data. Each set of text data has character data and color data. The calculating unit calculates, for each set of color data, an appearance ratio at which a subject set of color data appears in the print data. The color data determining unit determines the color data having a highest appearance ratio among a plurality of appearance ratios of a plurality of sets of color data as first color data, and determines the color data except for the first color data as second color data. The appending unit appends first attribute data to the character data included in the text data having the first color data, and appends second attribute data to the character data included in the text data having the second color data.

Abstract: An image forming system includes: a data conversion unit that converts first image data into second image data; and an image output unit that outputs an image obtained by reproducing the second image data. The data conversion unit includes: a determination unit which divides the first image data into a dot block each includes plural pieces of dot data, and determines whether or not an array of dot data included in each dot block corresponds to a specific array; and a replacement unit which replaces the data out of the second image data, which is located in a portion corresponding to the dot block, with first replacement data including image forming dot data with which an image is formed. The specific array includes a first array in which the dot data to be thinned out is configured as the image forming dot data, and the dot data not to be thinned out is configured as non-image forming dot data with which an image is not formed.

Abstract: A color image processing device configured to process input color image data includes a specifying unit configured to specify a gray region including a gray axis within a color gamut of the input color image data in a color space, a first setting unit configured to set a first gray stabilization region away from the gray axis in the color space so as to satisfy a predetermined condition, and a first transferring unit configured to transfer each color within the gray region specified by the specifying unit into the first gray stabilization region.

Abstract: An image forming system includes: a data conversion unit that converts first image data into second image data; and an image output unit that outputs an image obtained by reproducing the second image data. The data conversion unit includes: a determination unit which divides the first image data into a dot block each includes plural pieces of dot data, and determines whether or not an array of dot data included in each dot block corresponds to a specific array; and a replacement unit which replaces the data out of the second image data, which is located in a portion corresponding to the dot block, with first replacement data including image forming dot data with which an image is formed. The specific array includes a first array in which the dot data to be thinned out is configured as the image forming dot data, and the dot data not to be thinned out is configured as non-image forming dot data with which an image is not formed.

Abstract: An image processing device includes a storing unit and a creating unit. The storing unit stores a dither matrix. The dither matrix has a plurality of dot regions and has a threshold value at each of the dot regions. The plurality of dot regions are divided into a plurality of sub-matrices. The creating unit is configured to create binary image data by comparing an input value to the threshold value. The plurality of sub-matrices includes a first sub-matrix and a second sub-matrix. The first sub-matrix has a first threshold value smallest among threshold values in the first sub-matrix. The second sub-matrix has a plurality of threshold values that are smaller than the first threshold value and are arranged adjacent to each other. Each of all remaining sub-matrices has at least one threshold value smaller than the first threshold value. The plurality of sub-matrices include a third sub-matrix and a fourth sub-matrix.

Abstract: An image forming system includes: a data conversion unit that converts first image data into second image data; and an image output unit that outputs an image obtained by reproducing the second image data. The data conversion unit includes: a determination unit which divides the first image data into a dot block each includes plural pieces of dot data, and determines whether or not an array of dot data included in each dot block corresponds to a specific array; and a replacement unit which replaces the data out of the second image data, which is located in a portion corresponding to the dot block, with first replacement data including image forming dot data with which an image is formed. The specific array includes a first array in which the dot data to be thinned out is configured as the image forming dot data, and the dot data not to be thinned out is configured as non-image forming dot data with which an image is not formed.

Abstract: A printing control device includes an input image data acquiring unit, a threshold acquiring unit, a determining unit, and a generating unit. The input image data acquiring unit acquires input image data. The input image data includes a plurality of input pixel data. Each input pixel data has an input value. The determining unit determines, for each input pixel data, a difference related value based on a difference between the input value and a threshold value corresponding to the input value. The generating unit generates print data by generating, for each input pixel data, output pixel data based on the difference related value. The output pixel data expresses density corresponding to the difference related value.

Abstract: An image processing device includes an acquiring unit, a calculating unit, a color data determining unit, an appending unit, and a converting unit. The acquiring unit acquires print data. The print data includes a plurality of sets of text data. Each set of text data has character data and color data. The calculating unit calculates, for each set of color data, an appearance ratio at which a subject set of color data appears in the print data. The color data determining unit determines the color data having a highest appearance ratio among a plurality of appearance ratios of a plurality of sets of color data as first color data, and determines the color data except for the first color data as second color data. The appending unit appends first attribute data to the character data included in the text data having the first color data, and appends second attribute data to the character data included in the text data having the second color data.

Abstract: An image-processing method includes: acquiring multi-level tone print data expressed in multilevel tones; determining whether the acquired multi-level tone print data includes line data indicative of a line having a tone; replacing, if the print data includes the line data, the line data with specific line data based on the tone of the line data, the specific line data indicating a specific line having a prescribed tone value and a prescribed structure; and converting the multi-level tone print data to binary data after replacing the line data with the specific line data.

Abstract: An image processor includes a first dither data memory storing a first dither matrix, a second dither data memory storing a second dither matrix, a selecting unit selecting one of the first dither matrix and the second dither matrix, and a converting unit converting multi-value image data to binary data by comparing density of the multi-value image data to the threshold value set in corresponding element of the one of the first dither matrix and the second dither matrix selected by the selecting unit. The second dither matrix is configured of a plurality of sub-dither matrices. Each sub-dither matrix has a plurality of elements each assigned with a threshold value in a range from a maximum threshold value to a minimum threshold value. A set of threshold values from the minimum threshold value to a predetermined intermediate threshold value is assigned to elements in corresponding locations of each of the plurality of sub-dither matrices.

Abstract: A color image processing device configured to process input color image data includes a specifying unit configured to specify a gray region including a gray axis within a color gamut of the input color image data in a color space, a first setting unit configured to set a first gray stabilization region away from the gray axis in the color space so as to satisfy a predetermined condition, and a first transferring unit configured to transfer each color within the gray region specified by the specifying unit into the first gray stabilization region.

Abstract: An image forming system includes: a data conversion unit that converts first image data into second image data; and an image output unit that outputs an image obtained by reproducing the second image data. The data conversion unit includes: a determination unit which divides the first image data into a dot block each includes plural pieces of dot data, and determines whether or not an array of dot data included in each dot block corresponds to a specific array; and a replacement unit which replaces the data out of the second image data, which is located in a portion corresponding to the dot block, with first replacement data including image forming dot data with which an image is formed. The specific array includes a first array in which the dot data to be thinned out is configured as the image forming dot data, and the dot data not to be thinned out is configured as non-image forming dot data with which an image is not formed.