Abstract: As viewed for each processing unit in head shading (HS) processing, a processing unit width is more than one pixel, so that a threshold arrangement corresponding to a target quality of an image intended by a dither matrix is kept while a possibility of avoiding zero dots from being generated can be enhanced. Moreover, the threshold arrangement is kept while a possibility of generating the same number of dots in processing units can be enhanced. Consequently, the threshold arrangement corresponding to a predetermined target quality of an image intended by a dither matrix is kept while it is possible to reduce occurrence of uneven density caused by the HS processing. Thus, it is possible to prevent the threshold arrangement from being limited by the HS processing according to the degree of the reduction.

Abstract: In low-resolution processing (reduction processing) in which input image data is separated into character print data and image print data to generate print data of lower resolution than that of the input image data, if a plurality of pixels is simply reduction-processed to one pixel, color of a color image surrounding a character may change. In an image processing method, calculation for performing reduction processing so that the plurality of pixels in the input image data corresponds to one pixel in the print data is performed as follows. A ratio of using a pixel value of a character attribute pixel in the calculation is set to 0, or set smaller than a ratio of using a pixel value of an image attribute pixel. As a result, a change in the color of the color image surrounding the character can be prevented.

Abstract: Nozzles in a print head are arrayed in a density of 600 dpi. Moreover, a dither matrix has a size of 16 pixels×16 pixels in 600 dpi. The dither matrix is repeatedly used. In the meantime, each of rectangles represents an HS processing unit. WHS=3 pixels. As a consequence, the relationship of a least common multiple below is established in a nozzle array direction: 3×WD=16×WHS. In this case, the cycle of interference unevenness can be prolonged to the least common multiple between WD and WHS, that is, 48 pixels (3WD). In this manner, the size of the dither matrix is not an integral multiple of the HS processing unit width, so that the cycle of interference unevenness can be prolonged more than the size of the dither matrix. Thus, the interference unevenness can be hardly recognized.

Abstract: One dither mask having a highest spacial frequency is selected from a plurality of dither masks. Next, a granularity is obtained with reference to a table based on the selected dither mask and an ejection amount level per area. Moreover, a difference in granularity between adjacent areas is calculated with respect to all of the areas. A maximum value is obtained out of the obtained differences in granularity, and then, the maximum difference in granularity is compared with a determination threshold. When the maximum difference in granularity is the threshold or greater, it is determined whether or not a dither mask having a spacial frequency lower than that of the selected dither mask is stored in a memory. When there are dither masks having lower spacial frequencies, a dither mask having a spacial frequency lower by one level than that of the selected dither mask is selected.

Abstract: When an input image is shifted by 640 pixels from a test pattern with reference to the position of a nozzle, the remainder is obtained by dividing 640 pixels by pixels of the dither matrix in an x direction. For example, when the size of the dither matrix in the x direction is 256 pixels, the dither matrix is shifted by 128 pixels in a direction reverse to the x direction. In this manner, the phase of the dither matrix at the time of the quantization during test pattern printing matches the phase of the dither matrix at the time of the quantization during input image printing. Consequently, unevenness of the dither matrix at a position N becomes the same in both of the test pattern and the input image. The HS correction to density unevenness caused by the unevenness of the dither matrix becomes suitable for the input image.

Abstract: In order to print a unit area of a print medium by a first printing scan and a second printing scan, dither patterns are formed which can control the arrangement of dots on the print medium without adverse effects of density unevenness and graininess, that are caused by printing position displacement. Regarding first and second dither patterns, information indicating whether or not a threshold is already set to a reference pixel and one or more pixels around the reference pixel in the first dither pattern is obtained for cases where each pixel in the first dither pattern is the reference pixel. A pixel in the second dither pattern to which a predetermined pixel is to be set is determined based on the obtained information. The first and second dither patterns formed in the above manner are associated with the first printing scan and the second printing scan, respectively.

Abstract: As viewed for each processing unit in HS processing, a processing unit width is more than 1 pixel, so that threshold arrangement corresponding to a target quality of an image intended by a dither matrix is kept while a possibility of avoiding the zero number of dots from being generated can be enhanced. Moreover, the threshold arrangement is kept while a possibility of generating the same number of dots in processing units can be enhanced. Consequently, the threshold arrangement corresponding to a predetermined target quality of an image intended by a dither matrix is kept while it is possible to reduce occurrence of an uneven density caused by the HS processing. Thus, it is possible to prevent the threshold arrangement from being limited by the HS according to the degree of the reduction.

Abstract: Provided are an image processing apparatus and an image processing method capable of reducing color unevenness due to variations in ejection characteristics among a plurality of nozzles when printing an image using a plurality of inks. To that end, a first image which is made up a color with noticeable color unevenness and similar colors is printed onto a print medium. The user then specifies a color and a nozzle position where color unevenness has occurred. On the basis of these results, parameters are set for a correction table referenced by an MCS processor. In so doing, it becomes possible to address the factor causing the color unevenness, and mitigate the effects of color unevenness in a focused way without incurring increases in processor load, memory requirements, or processing time as compared to the case of calibrating all lattice points.

Abstract: In an image processing apparatus for encoding image data and a method of controlling the same, whether an attribute of each of a plurality of areas in image data corresponds to an edge in an image based on the image data is determined, and one of a plurality of sub-sampling processes is selected according to the determination for each of the plurality of areas. Note that the plurality of sub-sampling processes can sub-sample color difference components of each of the plurality of areas by different processes. By the sub-sampling process selected as that corresponding to each of the plurality of areas, each of the plurality of areas is sub-sampled to encode the image data.

Abstract: Provided are an image processing apparatus and an image processing method capable of reducing color unevenness due to variations in ejection characteristics among a plurality of nozzles when printing an image using a plurality of inks. To that end, a first image which is made up a color with noticeable color unevenness and similar colors is printed onto a print medium. The user then specifies a color and a nozzle position where color unevenness has occurred. On the basis of these results, parameters are set for a correction table referenced by are MCS processor. In so doing, it becomes possible to address the factor causing the color unevenness, and mitigate the effects of color unevenness in a focused way without incurring increases in processor load, memory requirements, or processing time as compared to the case of calibrating all lattice points.

Abstract: When a gradation mask is used to distribute image data to be recorded by overlapping portions in an overlapping head, color unevenness is generated in an image recorded by the overlapping portions due to a displacement in impact positions caused by an assembly error. As a result, accurate colorimetric measurement of patches recorded by the overlapping portion cannot be performed. To solve such a problem, a distribution ratio by which the image data is distributed to the overlapping portions is set to be approximately constant when recording a test pattern for performing color correction, as compared to when normally recording the image.

Abstract: There is provided an image processing method of laying out and outputting an image of an original formed from a plurality of pages on one page, the method comprising: inputting image data of the original formed from the plurality of pages; dividing the image data input in the inputting into a plurality of blocks; discarding unnecessary information; appending necessary information to each block obtained by division in the dividing based on the predetermined rule; replacing the respective blocks obtained by division in the dividing with the block from which the unnecessary information is discarded in the discarding, and the block to which the necessary information is appended in the appending; and outputting the respective blocks which have undergone replacement in the replacing by laying out the respective blocks on one page.

Abstract: This invention is directed to an image reading apparatus. In the apparatus, reading an original by irradiating it with light of three primary colors, respectively, and by receiving the reflected light is performed as follows. More specifically, an operation mode is designated, and conditions used to perform image reading are set in accordance with the designated mode. Under the set conditions, the image reading is performed according to a method of irradiating an original sequentially with beams of the three primary colors and reading the beams reflected by the original. Alternatively, under the set conditions, image reading is performed according to a method of irradiating an original simultaneously with beams of two primary colors in each of three different combinations of the three primary colors and reading the beams reflected by the original. Instead, image reading is executed twice according to these two methods.

Abstract: When the width of a recording head is greater than the width of a recording medium having a maximum conveyable width, a recorded image corresponding to ejecting ports in the entire area of the recording head cannot be corrected. Multiple correction test patterns are recorded using ejecting ports in part of the recording head, and correction data for correcting an image corresponding to ejecting ports in the entire area of the recording head on the basis of the colorimetric result of the test patterns. In this way, image data to be recorded by the ejecting ports in the entire area of the recording head is corrected.

Abstract: A sheet music creation method of creating sheet music whose layout is changed based on image data of sheet music input from an input device includes the steps of dividing the image data of the sheet music input from the input device into grand staffs, designating the grand staffs divided in the dividing in the order of performance, and re-editing, by a processor, image data representing the grand staffs in accordance with the order designated in the designating.

Abstract: When the width of a recording head is greater than the width of a recording medium having a maximum conveyable width, a recorded image corresponding to ejecting ports in the entire area of the recording head cannot be corrected. Multiple correction test patterns are recorded using ejecting ports in part of the recording head, and correction data for correcting an image corresponding to ejecting ports in the entire area of the recording head on the basis of the colorimetric result of the test patterns. In this way, image data to be recorded by the ejecting ports in the entire area of the recording head is corrected.

Abstract: This invention is directed to provide a method capable of performing filter processing suitable for each of different image reading methods. This method includes the steps of causing a light emitting unit to sequentially irradiate an image original with light components of three primary colors and read the image original, and causing the light emitting unit to simultaneously irradiate the image original with one of three different color combinations, which includes two of the light components of three primary colors, and read the image original. The method further includes the step of processing image data obtained based on the reflected light received by the light receiving unit after changing a filter to be used for image processing depending on whether reading of the image original is primary color reading or complementary color reading.

Abstract: A sheet music processing method of processing, by an image processing apparatus, image data of sheet music input by an input device, the method comprising setting, by a user using a designation unit of the image processing apparatus, a unit in which the image data of the sheet music is processed; dividing the image data of the sheet music into units corresponding to the unit; determining whether image data of a first one of the units is repeated in one or more others of the units; and processing the image data, when the image data of the first one of the units is determined to be repeated in the one or more others of the units, to append information using the image processing apparatus to the image data of the first one of the units and the image data of the one or more others of the units.

Abstract: This invention is directed to a method capable of performing satisfactory image reading by absorbing variations in each apparatus. According to this method, in primary color reading, light emitting unit sequentially irradiates an image original with light components of three primary colors and reads the image original, and in complementary color reading, the light emitting unit simultaneously irradiates the image original with one of three different color combinations, which includes two of the light components of three primary colors, and reads the image original. Each of the primary and complementary color readings includes image processing of executing shading correction of image data based on calibration data obtained by calibrating the light emitting unit when reading the image original.

Abstract: This invention is directed to a method capable of performing appropriate under color removal in image original reading. According to this method, under color removal of the original is performed as follows. A printing medium without any printed image is read by primary and complementary color readings. A brightness signal distribution is generated by converting, using a provisional table, each of image data generated by the reading methods. The lowest one of signal levels is selected from each of the distributions. In correspondence with each of the primary and complementary color readings, a conversion table is formed, which converts the image data to make a pixel value corresponding to the selected lowest one of the signal levels to a value representing white. Under color removal of the image data is performed using a corresponding conversion table in accordance with the reading method of the image original.