The occurrence of more and the deterioration of performance are suppressed. A data compression unit stores identification data indicating the presence or absence of periodicity, and printing data correlated with the identification data in a first memory area of a RAM. A color conversion processing unit that performs speculation processing stores printing data that has undergone color conversion processing corresponding to printing by a printer in a second memory area of the RAM. A screen processing unit that performs speculation processing performs AM screen processing on printing data. The screen processing unit confirms the identification data stored in the first memory area of the RAM by the data compression unit, and in a case where the identification data indicates there is periodicity, instructs to perform color conversion processing corresponding to printing by a copier on printing data, and performs FM screen processing on the printing data.

A flexographic printing plate includes at least one halftone printing area with a plurality of halftone dots. A halftone dot of said plurality of halftone dots is shaped as a relief area. Said relief area includes a central portion and a surrounding portion. Said central portion has a central dot floor with a first pattern of a plurality of pins protruding upwardly from the central dot floor. Said surrounding portion protrudes upwardly from the central dot floor and has a top side including a second pattern of a plurality of recesses. The first pattern and second pattern are such that the surrounding portion can be distinguished from the central portion.

The occurrence of moire and the deterioration of performance are suppressed. A data compression unit stores identification data indicating the presence or absence of periodicity, and printing data correlated with the identification data in a first memory area of a RAM. A color conversion processing unit that performs speculation processing stores printing data that has undergone color conversion processing corresponding to printing by a printer in a second memory area of the RAM. A screen processing unit that performs speculation processing performs AM screen processing on printing data. The screen processing unit confirms the identification data stored in the first memory area of the RAM by the data compression unit, and in a case where the identification data indicates there is periodicity, instructs to perform color conversion processing corresponding to printing by a copier on printing data, and performs FM screen processing on the printing data.

An image processing apparatus that converts image data of a first resolution into image data of a second resolution lower than the first resolution. The image processing apparatus determines a small dot that is included in the image data of the first resolution and matches a first small dot pattern and performs conversion from the first resolution to the second resolution by switching a method of generating resolution-converted image data based on a result of the determination.

For a multi-pass printing, an image of a unit area is printed by M printing scans of M print regions of first and second nozzle arrays. Each of N pieces of column data is printed by a different printing scan. Ejection data for the first nozzle array is generated using a first mask pattern and ejection data for the second nozzle array is generated using a second mask pattern different from the first mask pattern, for each of the N pieces of column data. On that basis, the first mask pattern and the second mask pattern have a complementary relationship in each of the M print regions. Further, in each of the first mask pattern and the second mask pattern, a combination of print regions, of the M print regions, for printing dots at the same position on the print medium has a mutually complementary relationship.

An image processing apparatus generates and outputs a binarized output pixel value corresponding to an input pixel value; and includes a filter processing unit, a quantizer, and a buffer. The quantizer is configured to quantize a pixel value after a filter process performed by the filter processing unit and thereby generate the output pixel value. The buffer is configured to store for each pixel a difference between (a) a sum of the pixel value after the filter process and the input pixel value and (b) the output pixel value. Further, the filter processing unit performs a bandpass filter process on the basis of the difference stored by the buffer.

In an example method, a set of source pixels corresponding to an image to be printed and a dot pattern of pixels including information to be encoded across the image are received. The dot pattern of pixels is mapped to a corresponding subset of the source pixels. A value of a clipping channel color in the subset of the source pixels is modified based on an original value of the clipping channel color for each pixel in the subset. The clipping channel color is used to detect the dot pattern of pixels. The image including the subset of pixels with modified clipping channel colors is printed.

The image processing apparatus of the present invention includes: an image data acquisition unit configured to acquire image data; a generation unit configured to generate an ejection pattern of ink droplets from the image data, which are ejected for forming dots from a plurality of nozzles of an image forming apparatus; a characteristic acquisition unit configured to acquire an ejection characteristic of ink droplets of the image forming apparatus; and a pattern change processing unit configured to change the ejection pattern based on the ejection characteristic and the ejection pattern, and the pattern change processing unit repeatedly performs, in a case where a gap occurs between dots that should be formed so as to contact each other by the image forming apparatus, the ejection pattern change until the gap is eliminated.

For a dither matrix used when converting multivalued data into image data for an output apparatus, thresholds are set such that a first dot and a second dot alternately become larger until both of the first dot and the second dot reach a first dot size, after both of the first dot and the second dot reach the first dot size, the first dot becomes larger until the first dot reaches a second dot size while the second dot does not become larger, and, thereafter, the second dot becomes larger until the second dot reaches the second dot size while the first dot does not become larger, and after both of the first dot and the second dot reach the second dot size, the first dot and the second dot alternately become larger.

In an example method, a dot pattern of pixels including information to be encoded across an image is mapped to a corresponding subset of the grayscale source pixels corresponding to the image to be printed. A value of a grayscale pixel in the subset of the grayscale source pixels is modified based on based on a predetermined threshold pixel value. The value of the grayscale pixel is decreased in response to detecting that the predetermined threshold pixel value is exceeded. The clipping channel color is used to detect the dot pattern of pixels. The image including the subset of pixels with modified values is printed.