Abstract: All threshold data applied to processing is read into a register so that threshold data read from threshold matrix memory can be recycled until the end of a scanning line for processing, and is selectively output to a plurality of comparison means for executing parallel comparison processing. The threshold data set in the register is shifted in order for repetitive use. The threshold data of the next scanning line is read into the register during the comparison processing, and upon completion of processing of one scanning line, comparison processing on the next scanning line is executed as pipeline processing. Threshold data read from the memory needs to be executed only once for each scanning line for processing, and threshold data can also be read during halftone data generation of the preceding line.

Abstract: An image display apparatus of the present invention includes an image display unit and an image reproduction module that generates display video data, which is to be displayed on the image display unit. The image reproduction module has an image transition controller that uses a predetermined image selection mask to process a first image and a second image and thereby generate the display video data in the case of changing display on the image display unit from the first image to an image including the second image in at least part of a display area of the first image. The image transition controller includes: a storage module that stores therein the first image, the second image, and a base selection mask having an image area of a smaller size than the at least part of the display area; and a selection mask conversion module that converts the base selection mask into the image selection mask having an image area of an identical size with the at least part of the display area.

Abstract: An image processor unit minimizes image-quality degradation that can be caused by the addition of predetermined information to an image and that enables the predetermined information to be added to the image so that embedded information can be accurately extracted. The image processor unit includes an input unit for inputting the image; a plurality of quantization-threshold setting unit, of which occurrence probability distributions are different from one another, for setting quantization thresholds in terms of probability; a control unit for controlling a regularity for selection of the plurality of quantization-threshold setting unit in units of a predetermined image region according to the predetermined information; and a quantizing unit that uses quantization thresholds set by the quantization-threshold setting unit and thereby quantizes the image according to an error diffusion method.

Abstract: A digital imaging system includes a color appearance handling capability that utilizes a database including actual image data and information relating to the actual image data to control illumination and color in digital images. The digital imaging system controls illumination and color with a color-by-correlation technology that includes an illuminant detection training algorithm that bases control of illumination and color on a database storing actual illuminants, scenes, and subjects from representative image acquisition devices such as digital cameras and scanners. In one example, illuminant detection training is accurately rendered for a variety of illuminants, scenes, and subjects that are expected to be of interest to users of a particular camera or group of cameras. In the example, the database is formed by user-group submissions from users of a particular camera or group of cameras.

Abstract: An interface section analyzes print data including data for identifying an object or data showing the setting of color processing and others and sets required color processing in units of a printed page. According to the set color processing, a color processing section sets corresponding color correction table and halftoning processing table in a high speed random access memory for example. The interface supplies a drawing instruction together with attribute data corresponding to the setting in the color processing section to a drawing section. The drawing section plots image data composed of color data every dot according to the drawing instruction and stores the drawing instruction together with the attribute data every dot in an image memory.

Abstract: A method of correcting image saturation is performed by defining saturated colors in a chromaticity color space; and deriving an overall correction of the saturation of colors in the image using the defined saturation of these colors in conjunction with a table of corrections indexed by hue and lightness. This process has a unique attribute of being able to automatically decrease saturation in regions of an image where oversaturation is detected.

Abstract: A look up table LUT with specific gray reproduction characteristics is used for converting RGB image data to multi-tone data of ink colors. The gray reproduction characteristics of LUT are set such that the color difference ?E of a gray color area with an arbitrary tone level in the L*a*b* color system is kept at about 4 or less, assuming that the results are observed under two different light sources, such as standard light D50 and standard light A, respectively.

Abstract: The present invention includes a system, method, and article of manufacture for decompressing a bit stream of compressed data representing a plurality of image blocks. This includes a two-step method of processing both a DC code and a plurality of AC codes. With respect to the processing of the AC codes, a plurality of bits of compressed input data relating to the AC codes are first retrieved from the bit stream. A first decoding operation is then executed based on the obtained compressed input data in order to generate first output data. It is then determined whether sufficient space is available for the first output data. If it is determined that there is sufficient space for the first output data, the first output data is outputted. On the other hand, if it is determined that there is insufficient space for the first output data, an alternate second decoding operation is executed in order to generate second output data.

Abstract: In an image processing method, on the basis of input image data with respect to a target pixel, independent multi-level data (g0, g1) corresponding to respective plural species of dots which are different in at least one of a density and a diameter are generated, and then data (O0, O1) relating to an amount of generation of the dots with respect to the target pixel are generated on the basis of a relationship between the generated independent multi-level data (g0, g1) corresponding to the plural species of dots. The image processing method is effective in performing design having a high degree of flexibility in proper use of a relatively high power dot (high density dot or large dot) and a relatively low power dot (low density dot or small dot) and can realize obviation or alleviation of an occurrence of granulation or an apparent frame caused due to the relatively high power dot.

Abstract: What is disclosed is an image path that advantageously uses halftone classification to select appropriate mappings in gray-scale management and color management operations. The tags generated in the scanner help identify different classes of halftones. One is selected from several pixel-value mappings to provide proper compensation. That is, the one-dimensional and multi-dimensional pixel-value mappings within the color management module are selected based on halftone classification tags from the scanner. The tagging is either one bit that indicates “Low Frequency Halftone” and “Not LFHT”, or, more preferably, the tag is multi-bit indicating a frequency bin that contains the frequency of the input halftone. Additionally, the multi-bit tag can indicate particular halftone screen types, such as dot screens, line screens, stochastic screens or error diffusion.

Abstract: A data processing method for a color management module (CMM), applying to image processing, including dividing an object data respectively into a meta file data, a CMM profile data and a screening/half-toning table. The meta file data is processed by a firmware of a printer, while the CMM profile data and the screening/half-toning table are processed by an application specification integrated circuit in the printer, thereby shortening the total time of data processing and thus improving the printing speed.

Abstract: A color output device is generally driven by at least three independent control signals for control of its response. A desired response in device independent color space is normally obtained by employing a cascade consisting of a characterization transform and calibration transform. The calibration transform transforms input control variables into output control variables that are directly used to drive the device. Input control variables can be transformed into intermediate control variables, which can be then mapped to output control variables utilizing a two-dimensional transformation. The two-dimensional calibration architecture provides improved control functionality and flexibility.

Abstract: A RIP system (100) includes a multi-screening information generator (102) for generating a multi-screening information file (Dms) which is an XML-format file containing information such as screen ruling, dot shape and screen angle, necessary for assigning a multi-screening operation, and discloses the multi-screening information file (Dms) to outside of the RIP system by storing in a shared disk or a flexible disk. On an input data creation process side, a client machine makes reference to the multi-screening information file (Dms), and thereby assign the multi-screening operation.

Abstract: The present invention implements a CMYK to CMYK pre-transform in front of at least one printer to be clustered where the transform is designed to ensure that the printers addressed through the pre-transform have substantially identical output color for substantially identical input CMYK values. As one form of implementation a method is disclosed to build CMY to CMY 3D-LUTs and 1D-LUT for K using sensors in the field. Making use of a system LUT—CMY to CMY 3D-LUT and a K to K 1D-LUT—improves consistency and provides a coherent control strategy and a means to provide standardized input CMY and K values in a clustered environment so that single or multiple vendor DFEs see substantially identical CMYK values.

Abstract: A method of generating a stochastic screen for use in printing a halftone containing image on a surface, where the generated stochastic screen comprises an array of threshold values each of which represents a halftone threshold at which pixels are printed at the corresponding location. The method comprises a) entering a first threshold value into the array and b) for a first halftone level, defining a number of threshold values to be entered into the array and, for each threshold value to be placed, for each of a number of candidate locations in the array, computing a distance function between the candidate location and the locations of threshold values already placed into the array, and placing the threshold value into the array at a location for which the distance function is substantially minimized. The process of step b) is then repeated for each subsequent halftone level.

Abstract: From a first threshold mask having threshold values corresponding to the number of gray levels, which is larger than that of an input image, a second threshold mask having threshold values corresponding to the number of gray levels, which is equal to that of an input image, is generated on the basis of tone reproduction characteristics corresponding to the type of paper used in a printer or the printer state. Using the generated second threshold mask, the number of gray levels of the input image is converted, and the converted image is output to an output apparatus. In this manner, a high-quality image can be output by making halftone conversion corresponding to the tone reproduction characteristics of the output apparatus by a small memory size without decreasing the number of gray levels of the input image.

Abstract: On the basis of a standard one-dimensional LUT 412, a plurality of one-dimensional LUTs 413 having mutually different tones are generated. Next, a plurality of monochrome sample images are generated using this one-dimensional LUTs 413, and a catalog print in which these monochrome sample images are arranged is printed out. Once the user has selected from the catalog print a sample image having the desired tone, a monochrome image is printed out using the one-dimensional LUT 413 that corresponds to the sample image.

Abstract: When the resolution for a specific gradation is enhanced, the resolution for the other gradations can be relatively degraded. It used to be difficult to carry out color conversion with accuracy in the high-lightness range without the occurrence of tone jump. A color conversion table which defines the correspondence between ink value data which specifies the ink quantities of inks in individual colors used in a printing device and the color component values of various colors used in another image device is generated. At this time, correction for interpolation accuracy enhancement is carried out beforehand so that colors in the low-lightness range will be larger in number than colors in the high-lightness range. This is intended to compensate the resolution which is relatively degraded in the low-lightness range by correction for resolution enhancement by interpolation accuracy. Thereafter, correction for resolution enhancement is carried out to create the ink value data.

Abstract: A method for constructing a transform for a predetermined display or printer, such printer or display being adapted to form a color image, on a particular medium, with extended chroma values while maintaining existing luminance values, the input to the transform including an input color digital image produced by a particular image capture device, the method includes providing a luminance reproduction curve in response to the input color digital image which, for any input luminance value, will produce an output luminance value, the luminance reproduction curve being selected to preserve highlight and midtone contrast, and shadow detail from the input color digital image; providing a plurality of selective luminance independent chromatic reproduction curves in response to the input color digital image which, for any input chroma value, will produce an output chroma value; and the chromatic reproduction curves being selected so that each curve is a function of the visual density range of the display or medium an

Abstract: The present invention generally provides methods and systems for printing. A statistical learning system is used to determine dot gain.

Abstract: A method and apparatus is used for preserving a black channel when a reference color space without a black channel is used to convert between a source black channel color space and a destination black channel color space. In one embodiment, the preservation and conversion system receives an image represented in a black channel color space and converts it to a reference color space, correlates at least one channel from the reference color space with a black output level that identifies a look-up table (LUT) for color values and a weight for interpolating the color values in the LUT for a destination device, interpolates between color values in at least two LUTs using the weight, and converts the image in the reference color space to the destination the black channel color space using the black output level and interpolated color values in the LUT.

Abstract: An image reproduction engine which causes toner to adhere to a development region of certain area located at a certain position within dots according to image reproduction data is utilized for image processing, wherein a halftone is expressed by means of halftone spots formed from a plurality of dots. The centroid of the halftone spot formed from a single dot or a plurality of adjacent dots is shifted from the center of the dot to an arbitrary position, thus achieving desired screen angles or desired pitches of halftone spots. As a result, screen angles related to an irrational tangent can be realized, and the pitches of halftone spots of a plurality of color screens can also be made uniform. 31.

Abstract: In one embodiment, a print system includes an anticipated ambient lighting selector to allow selection of an anticipated ambient lighting. A rendering module is configured to map a print job into raster data configured to reduce color cast in gray output when displayed under the anticipated ambient lighting.

Abstract: Disclosed is a system of image data conversion, capable of setting conversion characteristics with more ease even for data having mixed image attributes, and of reducing the amount of data and the size of memory required. The conversion system includes processing elements in a processor array, each including at least an input data register, character registers, an attribute register, and a global processor, so that a calculator in each of the processing elements operates to select, and store in the character registers, the data set, xi, yi, and ai, corresponding to attribute data stored in the attribute register, to be conversion processed subsequently according to an expression stored in the global processor.

Abstract: A gradient-based trapping apparatus includes a processing device for receiving a current portion of a digital image. If the current portion includes an edge, a trapping device produces a trapped portion. The trapped portion represents the current portion with varying colors. The trapping device produces the trapped portion based on a plurality of patterns. Each of the patterns is chosen as a function of at least one of a) a distance of a current pixel within the current portion from the edge, b) at least one of a plurality of colors within the current portion, and c) a width of the trapped portion.

Abstract: A method and system for halftoning images that uses error diffusion with partial dots is provided. First, an input picture element (input pixel) that has a picture level (e.g., gray level) is received. Next, a reproducible gray level is generated based on the gray level of an input pixel. Then, a corrected gray level is generated based on the gray level of an input pixel and an error amount (e.g., error propagated or diffused from adjacent areas or pixels). A determination is made whether the corrected gray level is in a predetermined relationship with a threshold. When the corrected gray level is in a predetermined relationship with the threshold, the reproducible gray level (i.e., partial dot size) is provided as output. When the corrected gray level is not in a predetermined relationship with the threshold, a zero value is provided as output.

Abstract: A method of mapping an input color gamut of an input device onto an output color gamut of an output device includes establishing a threshold chroma value in the input color gamut. For first input chroma values below the threshold chroma value, each first input chroma value is mapped onto a respective one of a plurality of first output chroma values such that a first linear relationship exists between the first input chroma values and the first output chroma values. Each corresponding first input lightness value is mapped onto a respective one of a plurality of first output lightness values such that a second linear relationship exists between the first input lightness values and the first output lightness values. For second input chroma values above the threshold chroma value, each second input chroma value is mapped onto a respective one of a plurality of second output chroma values such that a first non-linear relationship exists between the second input chroma values and the second output chroma values.

Abstract: A color image halftoning apparatus and method for creating a color bilevel image from a color output device, and mask generation apparatus and method used in the color image halftoning apparatus and method are provided. The color image halftoning apparatus includes: an address generator that receives a pixel in an image intended for halftoning and generates an address corresponding to the position of the pixel in a mask memory storing mask threshold values for one color channel; a mask generator that receives a mask threshold corresponding to the address from the mask memory and generates a mask threshold value for each of a plurality of color channels; and a comparison unit that sequentially receives the mask threshold value generated for each of the plurality of color channels and the pixel value in the image intended for halftoning, compares both values, and outputs a bilevel value according to a predetermined rule.

Abstract: The user needs the skill to select a pixel interpolating process and a gradation converting process and it is difficult to select an optimum process adapted to desired printing quality. In a printing system using a computer system (10), by allowing a factor such as printing paper which exerts an influence on printing quality to be selected (step 400), the printing quality is estimated from the selected printing paper, a proper printing control which is preliminarily made correspond is selected (step 410), and a process is branched so as to execute the selected printing control (steps 420 to 450, steps 460 to 480), thereby enabling an optimum printing control to be performed.

Abstract: Color processing architecture and algorithms (CPAA) for color laser printers process and handle incoming RGB image data effectively to achieve high performance, high quality image printing with low memory requirements. CPAA supports a new data structure for faster raster operation processing (ROP) for color laser printers. The CPAA architecture advantageously improves the flow of data through the processing pipeline to provide high speed at higher resolutions, e.g., at 600 and 1200 dpi. An advance quantizer using multilevel dithering flexibly reduces bits to support fast ROP and to enable fast conversion to CMYK data with only a simple look-up table (LUT) operation by a color matching module, while an adaptive filter maintains high image quality.

Abstract: Xerox Reference No. D/A0639A system and method for improving xerographic halftoning by magnifying a threshold array, interpolating the in-between values, enabling multiple thresholds to be accessed simultaneously and presented to multiple comparators, to cause multi-bit output. A threshold array is sampled at distinct locations separated by the sparse sampling distance to allow warping of the threshold array dots by adjusting the sampling distance in small, fractional portions (deltas) of the magnified distance. By adding more thresholds, amplitude or intensity modulation is used to move dot edges in a process direction for further flexibility in printing irrational or warpable screens.

Abstract: A color printing system includes a color printer adapted to receive an image file and an original color profile associated with the image file and print at least one color output based on the image file and the original color profile. The color printing system also includes a color measurement module adapted to generate a color measurement of the color output of the color printer and a color management module adapted to compare the color measurement of the color output of the color printer with the original color profile associated with the image file. As such, the color management module determines if a variation in color exists between the color measurement of the color output and the original color profile. Thus, the color printing system also includes a color profile manager adapted to modify the original color profile and create a modified color profile if the color management module determines that the variation in color exists.

Abstract: Method and apparatus for performing halftoning of an image, using two 2-dimensional look up tables (LUTS). The first LUT receives coordinates of an image value and outputs a screen reference value which then serves, together with the image value as address for the second LUT. The output of the second LUT is the halftone value.

Abstract: A threshold mask for converting a contone image to a halftone image defines halftone cells that define halftone dots that undergo a growth in population as tone levels increase. After some growth in population, the halftone cells define halftone dots that then grow in size from a first predetermined size as tone levels increase further. During the growth in population, the halftone dots having a second predetermined size are placed into halftone gaps. The second predetermined size is smaller than the first predetermined size. In the simplest implementation, FM screening is used up to a tone level where the FM dither pattern holes begin to become visible. At this point AM screening is applied only to the remaining dot centers (corresponding to those holes) until they reach the stable dot size. Then, the dots are further grown according to the method used outside of the FM regime (e.g. the conventional AM process). In the FM regime, two types of visual disturbances can arise.

Abstract: The present invention addresses the reformatting of a digital “ready to print” data file into a continuous tone (32 or 24 bit) file whereby discrete values in the tone range are uniquely assigned to specific binary combinations. The purpose for this transform is to facilitate further manipulation of preprocessed data. One application of the present invention is to exist as a critical piece of proofing workflow for a technology that reduces continuous tone data into a binary form representing droplet selection prior to output.

Abstract: An image processing system which includes: a threshold table selecting unit for selecting one of a plurality of threshold reference tables in accordance with an angle of rotation for bit map data having an attribute of rotation to thereby generate a threshold; a gradation modulating unit for performing gradation modulation by use of the threshold generated by the threshold table selecting unit to thereby obtain gradation-modulated data; a buffer unit having a plurality of buffers and for storing the gradation-modulated data of the gradation modulating unit into the plurality of buffers; an addressing unit for designating respective storage addresses for the plurality of buffers of the buffer unit; a rotating unit for rotating the gradation-modulated data; and a storage unit for storing contents of the buffer unit into the addresses designated by the addressing unit and outputting the gradation-modulated data rotated by the rotating unit.

Abstract: The present invention is an apparatus and program storage medium storing a program for processing images, which receives CT image data and LW image data sent from an RIP, corrects and synthesizes the received CT image data and LW image data whereby generating an image data that represents an image having both a continuous gradation image region and a line drawing region, and sends the generated image data to a printer. Based on the received CT image data and LW image data, CT image data and LW image data to be corrected are obtained from the respective correction lookup tables, and a random number is added to each of the obtained CT image data and the LW image data to be corrected. The CT image data and the LW image data having the respective random numbers added are then synthesized and transmitted to the printer.

Abstract: Color values of a color space are stored in a color correction table. A smoothing process is performed on achromatic color values to remove artifacts and prevent image degradation caused by the correction process. The color values obtained from the smoothing process may also be adjusted for projection onto the achromatic axis.

Abstract: Discloses an image formation apparatus capable of achieving a picture quality improvement of a multi-value image without increasing the size of a look-up table to a size larger than the size of a look-up table that is used for the picture quality improvement at the time of forming two-value image data. The image formation apparatus can form an image having at least one density in addition to two values of white and black in pixel units, and includes a density separation section that distributes a multi-value image data to a plurality of density planes according to a predetermined rule, a correction signal generator that outputs correction signals for correcting the layout of pixels in each of the plurality of density planes, and a correction signal combiner that combines the correction signals output from the density planes according to a predetermined combining rule.

Abstract: A color image processing apparatus using a gradation image recording method by pulse width modulation comprises a pulse width selection table determining section for determining a pulse width selection table for pulse width modulation, a gradation correction table determining section for determining a gradation correction table based on the determined pulse width selection table, a color conversion table determining section for determining a color conversion table based on the determined gradation correction table, and a color image processing section for correcting a given color image signal and outputting the corrected color image signal based on the determined color conversion table, the gradation correction table and the pulse width selection table. Consequently, a color image processing can be carried out more properly by determining each table and performing an image processing operation in order of a degree of freedom.

Abstract: A method for generating an image-dependent tone scale curve includes (a) computing an image activity histogram for an input image value as a function of the number of neighboring pixels that have a predetermined amount of image modulation exclusive of a predetermined noise modulation; and (b) constructing an image-dependent tone scale curve from the image activity histogram. The predetermined amount of image modulation may comprise any image value within two specified intervals each bounded by a noise threshold and a modulation threshold. In another aspect, a tone scale curve that optimizes the rendering of image activity is generated under one or more constraints. More particularly, one or more slope-limit constraints and/or point constraints are established and then a tone scale function is constructed by applying the slope-limit constraints in a tone scale derivative space. An image activity histogram is computed and applied to the tone scale slopefunction.

Abstract: ROM stores an 8×8 base matrix of 64 sequential threshold values (1-64), hexadecimal data for a specified pattern to be rendered on an output image, and a threshold address table in which the thresholds of the base matrix are arranged in ascending order of threshold value. The MPU generates a second threshold matrix used to render the specified pattern when the matrix is used by dithering unit to dither a source image having a wide range of gray-scale levels.

Abstract: A gray scale image processing method which converts an input image, each pixel of which has a value between 0 and N, to an output image, each pixel of which is represented by a gray scale value of A levels. The method has a generation step of generating B reference images, in each of which each pixel is represented by a gray scale value of the A levels, from B elementary images, in each of which all pixels have the same value between 0 and N, using one or more different error distribution matrixes according to said A levels, a selection step of selecting one of the B reference images based on a pixel value f(x,y) of the input image at coordinates (x,y) and an output step of outputting a pixel value represented by a gray scale value of the A levels of the selected one of the B reference images at a position corresponding to the coordinates (x,y).

Abstract: A drawing instruction processor refers to a bitmap line table that shows whether the bit arrays in the row unit are the same in the order of concentrations. The drawing instruction processor decides whether dither patterns to be used for the adjacent specified drawing ranges are the same, by referring to the BLT, and links the drawing ranges to which the same pattern can be applied. Based on this, the drawing processor carries out a batch writing using a dither pattern prepared in advance into the specified range in the page memory. The dither pattern to be used for the drawing is prepared by linking a plurality of the same basic patterns to have a length corresponding to the length of the word length. As a result of such an arrangement, it is possible to achieve a high-speed processing.

Abstract: A graphics language interpreter includes one or more color converters that accept input color values and that algorithmically convert such input color values to output color values. The color converters are specified by a standard that defines the predefined graphics language. The color converters use color conversion algorithms that are potentially specified by graphics commands during rendering. A lookup component is associated with the color converters. The lookup component indicates output color values corresponding respectively to selected input color values. The lookup component is initialized with output color values that are converted from the selected input color values by the converters. During rendering, the graphics language interpreter uses the lookup component rather than the one or more color converters to convert input color values to output color values.

Abstract: An improved color correction system, and more specifically, a color profiling system for a printer and scanner. Highly accurate device independent printer profiles are generated using a scanner and processing means. The process utilizes the simultaneous scanning of a reference target and a print target to produce a scanner profile. Uncompensated printer profile is developed using the scanner profile, and compensation transforms convert the uncompensated printer profile into the printer profile.

Abstract: This invention concerns a printer driver for a high performance color printer, such as a printer using a page-width drop-on-demand inkjet printhead. In another aspect it concerns a method of printing. The printer driver manages a two layer page buffer into which image objects are composited during page construction. The first layer contains contone data while the second layer contains bi-level data. The bi-level data is will be composited over the contone data by the printer. The printer driver operates such that where there is contone data composited with the contone layer that obscures bi-level data, the obscured bi-level data is removed from the bi-level layer and either discarded, or in the case where there is some interaction between the image represented by the obscuring contone data and the image represented by the obscured bi-level data, then the bi-level data is composited with the contone data before the obscuring contone data is composited with the contone layer.

Abstract: Optimally determined halftoning algorithms are applied to tone values by selecting among combinations of at least two algorithms that best address the tradeoff between output quality and rendering performance. Input tone values are scrutinized and matched with the algorithm combination that processes the associated tone values in a manner that increases performance (including data compressibility) without sacrificing output quality. The selection process is computationally simple and fast. Reliability is ensured because the combinations of halftoning algorithms are tabulated as a result of analysis of test samples of the printed output.

Abstract: When image data to be transferred to a CD-R writer is inputted from a scanner to an image data exchanger, property information (information expressing attributes of the image data, information expressing the input source/output location of the image data, or the like) is added to the image data, and then the image data is stored in a spool. When the image data is fetched from the spool, on the basis of the property information, image processing corresponding to attributes of the image data and to an output location (the CD-R writer) is carried out, and then the image data is transferred to the CD-R writer.

Abstract: The present invention relates to an image processing method, an image processing apparatus and a recording medium that convert a grey scale image into an area gradation image. The present invention intends to provide an image processing method, an image processing apparatus and a recording medium capable of increasing processing speed in a state where high image quality is maintained. In the image processing method and the image processing apparatus according to the present invention, image data of a C component and image data of an M component in grey scale image data are converted into halftone image data in accordance with an error diffusion method, and image data of a Y component are converted into halftone image data in accordance with a blue noise mask method.