A block configured with Nb pixels included in image data is classified into Nt groups, position information which is information indicating a position of the pixel configuring is created, a block gradation value is decided by a data amount smaller than a data amount required for representing gradation values of the Nb pixels based on the gradation value for each pixel configuring each group, for each of the Nt groups, dot arrangement which is information indicating the presence or absence of dot formation for each pixel configuring the block is temporarily decided based on the block gradation value, for each of the Nt groups as the target, the dot arrangement targeting the block is decided by using the temporarily decided dot arrangement and the position information, and it is determined whether or not the dot arrangement decided by the dot arrangement deciding unit is corrected by using an error diffusion method.

There are provided a printing system, a method of generating a halftone processing rule, a method of acquiring a characteristic parameter, image processing device and method, a halftone processing rule, a halftone image, a method of manufacturing a printed material, an ink jet printing system, and a program which are capable of reducing an operation load of a user and acquiring a halftone processing rule appropriate for the printing system. A characteristic parameter acquisition chart (100) including a pattern for acquiring characteristic parameters related to characteristics of the printing system is output, and the output characteristic parameter acquisition chart (100) is read by image reading means. The characteristic parameters are acquired by analyzing the read image of the characteristic parameter acquisition chart (100), and halftone processing rules that define the processing contents of halftone processes used in the printing system are generated based on the acquired characteristic parameters.

An image forming apparatus that enhances measurement accuracy of a pattern image and improves quality of a printed image. Light emitted from a light emission unit based on a first measurement condition is reflected from an image bearing member, and first information is generated based on a measurement result of the image bearing member. Second information is determined based on the first measurement condition, the first information, and a second measurement condition. Light is emitted based on the first measurement condition when a first measurement image is measured, and an image forming condition is generated based on a measurement result of the first measurement image and the first information. Light is emitted based on the second measurement condition when a second measurement image is measured, and the image forming condition is generated based on a measurement result of the second measurement image and the second information.

A correction method for an image forming apparatus including a light source including a plurality of light emitting points, a photosensitive member configured to rotate in a first direction, and a deflection unit configured to deflect light beams emitted from the light source in a second direction orthogonal to the first direction to form scanning lines, the correction method including: a storing step of storing information on positional deviation of the scanning lines in the first direction; a conversion step of converting positions of pixels of an input image by performing coordinate transformation based on the information so that an interval of the scanning lines becomes a predetermined interval; and a filtering step of determining pixel values of pixels of an output image by subjecting pixel values of the pixels of the input image after the coordinate transformation to a convolution operation.

A method of processing a document for printing includes receiving a document; for at least one of the plurality of regions, determining a drop size for that region and determining whether the drop size for printing the region meets a threshold criterion and, if so, processing the region using a tile-based screen for halftoning and, if not, processing the region using an error diffusion screen for halftoning; and printing the processed regions. Another method includes additionally considering coverage level to determine whether to use a tile-based screen or error diffusion screen. Yet another method includes determining whether the region is within a threshold range of a drop step change.

Certain examples described herein relate to the embedding a pattern in an output content having at least two-dimensions, for example a printed output. Content data having at least two dimensions is processed to generate an array of spatial elements, each spatial element corresponding to a respective location in the output content and comprising a probabilistic distribution for a set of output material compositions. A threshold matrix is generated using pattern data corresponding to a pattern, and the array of spatial elements is halftoned using the threshold matrix. The threshold matrix is generated such that the pattern is embedded in the output content.

There are provided a printing system, a method of generating a halftone processing rule, a method of acquiring a characteristic parameter, image processing device and method, a halftone processing rule, a halftone image, a method of manufacturing a printed material, an ink jet printing system, and a program which are capable of reducing an operation load of a user and acquiring a halftone processing rule appropriate for the printing system. A characteristic parameter acquisition chart (100) including a pattern for acquiring characteristic parameters related to characteristics of the printing system is output, and the output characteristic parameter acquisition chart (100) is read by image reading means. The characteristic parameters are acquired by analyzing the read image of the characteristic parameter acquisition chart (100), and halftone processing rules that define the processing contents of halftone processes used in the printing system are generated based on the acquired characteristic parameters.

In an error diffusion process, a control device determines a dot value of a target pixel by using a gradation value of the target pixel, and an error value. The control device determines distribution error value by comparing a gradation dependent value with a first evaluated density value indicating a density of a first dot. The control device determines the distribution error value by using the first evaluated density value when the dot value of the target pixel indicates formation of the first dot and when the gradation dependent value is smaller than or equal to the first evaluated density value. The control device determines the distribution error value by using a modified evaluated density value greater than the first evaluated density value when the dot value indicates formation of the first dot and when the gradation dependent value is greater than the first evaluated density value.

A printing system and method to process image data is disclosed. The printing system includes an identification module and image pipeline module include a linear threshold array algorithm and a halftoning algorithm to process the image data. An image pipeline module applies a linear threshold array algorithm to line regions and a halftoning algorithm to the non-line regions.

A correction method for an image forming apparatus including a light source including a plurality of light emitting points, a photosensitive member configured to rotate in a first direction so that a latent image is formed thereon with light beams emitted from the light source, and a deflecting unit configured to deflect the light beams emitted from the light source in a second direction orthogonal to the first direction to form scanning lines, the correction method including a correction step of correcting sparseness and denseness of density in the first direction caused by deviation of the scanning lines in the first direction by moving a predetermined pixel in the first direction in accordance with the deviation of the scanning lines and causing a pixel value of the predetermined pixel to be output in accordance with a movement of the predetermined pixel.