JP2004021202A - Image processor and its method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processor and its method which takes into consideration printing of a color test chart solving the problem that although the color test chart has many signals of ≥300% in the sum of density signals that a printer do not guarantee, simple toner reduction results in that a color test chart which is effective in grasping device colors can not be obtained. <P>SOLUTION: A three-dimensional display device has means of: analyzing inputted image data and determining a process to be performed for the input image data (S101, S111, S113); performing the determined process for the input image data (S102, S103, S114); and outputting the input image data to a printer (S104, S117). When the input image data indicate printing of a color test chart, a process corresponding to the amount of coloring materials in use is determined (S114-116). <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image processing apparatus and an image processing method, for example, to an image processing for forming an image using a plurality of color materials.
[0002]
[Prior art]
Today, the quality of images output by electrophotographic printers and color copiers has dramatically improved, and has reached a level comparable to that of offset printing. This is due to the improvement of image forming processes such as charging, development, transfer, fixing, and cleaning, and the result of expanding the color reproduction range in the saturation direction of the toner.
[0003]
On the other hand, there has been an increasing tendency to connect a printer or a color copying machine to a network and use it as a multi-function printer (MFP). For this reason, images have been input from various devices to printers and color copiers via networks, and it has been difficult to match the colors of these images. To solve such inconveniences, various color management methods have been proposed. One of them is a color management system (CMS) using an ICC (International Color Consortium) profile, which is becoming a de facto standard.
[0004]
Today, a user creates an ICC profile of a printer on his / her own and outputs an image that has been subjected to color conversion by a computer device (PC) to a printer, or downloads the created ICC profile to a printer or a RIP (Raster Image Processor). Software and a colorimeter for a user to create a profile are commercially available. Therefore, an environment in which a user who has some knowledge can perform color matching with a target color is being prepared.
[0005]
Further, it is not known whether the printer for which the ICC profile has been created is used for the target or for the destination. Therefore, the conversion table for the target and destination (CMYK → L * a * b * and L * A * b * → CMYK conversion table), and many profile creation applications have such a configuration. In order to create an ICC profile having the above configuration, a patch covering CMYK signals, for example, 928 patches defined by ISO 12642 is output, and each patch is measured for color. , A color conversion table on the source side and the destination side is created.
[0006]
Assuming that the maximum density value of each density signal is 100%, the printer does not guarantee image formation of a signal whose sum exceeds 300%. This is because, when an image of such a signal is output, the amount of toner supplied to the photoconductor (hereinafter, referred to as “amount of glue”) is large. Insufficient fixing capacity of the toner due to insufficient heat capacity, and problems such as the recording paper being wound around the fixing roller occur.
[0007]
However, in the test form (928 patches and the like) defined in ISO 12642, there are many signals whose sum of density signals (hereinafter referred to as “signal sum”) is not guaranteed by the printer and is 300% or more.
[0008]
[Problems to be solved by the invention]
When a signal having a signal sum of 300% or more is input, a printer having a so-called toner reduction function that forms an image by limiting (converting) the signal sum to 300% in order to forcibly limit the amount of glue is also available. Exists. However, if the toner reduction function is used, the gradation continuity of the shadow part cannot be maintained, and the gradation characteristic becomes difficult to create an ICC profile.
[0009]
Further, as described in JP-A-2000-330413 and JP-A-5-127551, a problem in the fixing unit that occurs when the amount of gluing is large is caused by a decrease in the temperature of an unfixed image due to a temperature drop during continuous image output. This is limited to, for example, wrapping of the recording paper around the fixing unit, which occurs when the amount of output and the amount of leading end of the recording paper in the paper passing direction is large. Each patch for creating an ICC profile has an area of 1 cm ² Only patches that exceed the signal sum by more than 300% exist independently. Further, the color test chart for creating the ICC profile does not matter the print quality, and there is no problem even if the toner is scattered to some extent.
[0010]
However, the toner reduction function does not consider the above-described characteristics of the color test chart and uniquely limits the signal value to reduce the amount of glue. Therefore, when toner reduction is performed, an effective color test chart for grasping the device color may not be obtained.
[0011]
The present invention is to solve the above-mentioned problems individually or collectively, and aims to realize image processing in consideration of printing of a color test chart.
[0012]
[Means for Solving the Problems]
The present invention has the following configuration as one means for achieving the above object.
[0013]
An image processing apparatus according to the present invention includes: an input unit configured to input image data indicating a mixed state of a plurality of color materials; an analysis unit configured to analyze a usage amount of the color material from the input image data; It is characterized by comprising setting means for setting output conditions and forming means for forming an image based on the input image data on a recording medium based on the set output conditions.
[0014]
A control unit that analyzes input image data and instructs a process to be performed on the input image data; a processing unit that performs an instructed process on the input image data; and outputs the input image data to a printing apparatus. An output unit that performs printing according to the used amount of the color material when the input image data indicates printing without specifying color processing.
[0015]
The image processing method according to the present invention is configured to input image data indicating a mixed state of a plurality of color materials, analyze the usage of the color materials from the input image data, and set output conditions based on the analysis result. An image based on the input image data is formed on a recording medium based on the set output conditions.
[0016]
The method further comprises analyzing input image data, determining processing to be performed on the input image data, performing the determined processing on the input image data, and outputting the input image data to a printing apparatus. When the input image data indicates printing of a color test chart, a process according to the used amount of the color material is determined.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an image processing apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.
[0018]
It should be noted that the relative arrangement of the following components and display screens are not intended to limit the scope of the present invention unless otherwise specifically described.
[0019]
[First Embodiment]
Hereinafter, a color copying machine will be described in detail with reference to the drawings as an embodiment of an image forming apparatus according to the present invention.
[0020]
[Constitution]
FIG. 1 is a diagram showing a schematic configuration of a color copying machine.
[0021]
The color copying machine includes four image forming stations for forming images of magenta (M), cyan (C), yellow (Y), and black (K). Since the configuration of each image forming station is substantially the same, the configuration of the magenta image forming station will be described below, and the description of the image forming stations for other colors will be omitted.
[0022]
The image forming station includes a charger, a cleaner 4a, a developing device 2a, and the like around an electrophotographic photosensitive member (hereinafter, referred to as "photosensitive drum") 1a, which is an image holding member. The photosensitive drum 1a is rotatably supported, and a transfer section is disposed below each photosensitive drum 1a, between the developing device 2a and the cleaner 4a. The transfer section includes a transfer belt 31 common to each image forming station and a transfer charger 3a.
[0023]
Recording paper supplied from a plurality of paper feed cassettes 61 or a drawable manual paper feed tray 61a is conveyed under each image forming station by a transfer belt 31, and a toner image of each color formed on each photosensitive drum is formed. Are sequentially transferred to form an image on which the toner image is superimposed. The recording paper P on which the toner image is superimposed is separated from the transfer belt 31 and transported to the fixing unit 5 by the transport belt 62.
[0024]
The fixing unit 5 includes a fixing roller 51 rotatably supported, a pressure roller 52 that rotates while being pressed against the fixing roller 51, a lubricant applicator 53, and roller cleaners 54 and 55. Heaters 56 and 57 such as halogen lamps are arranged inside the fixing roller 51 and the pressure roller 52, and temperature sensors 58 and 59 such as thermistors are arranged near the surfaces of the fixing roller 51 and the pressure roller 52, respectively. Therefore, the temperatures of the fixing roller 51 and the pressure roller 52 detected by the temperature sensor are supplied to the temperature controller 60, and the temperature controller 60 controls the electric power applied to the heaters 56 and 57, so that the fixing roller 51 and the heating roller are controlled. The surface temperature of the pressure roller 52 is adjusted.
[0025]
The lubricant applicator 53 lubricates the surface of the fixing roller 51 with silicone oil so that toner does not adhere to the surface of the fixing roller 51 when the recording paper passes between the fixing roller 51 and the pressure roller 52. Apply as an agent. The lubricant applicator 53 is connected to an application amount control unit 63 for controlling the amount of silicone oil to be applied.
[0026]
A drive motor (not shown) that drives the fixing roller 51 and the pressure roller 52 is connected to a speed controller 64 that controls the recording paper conveyance speed, that is, the rotation speed of the fixing roller 51 and the pressure roller 52.
[0027]
With these configurations of the fixing unit 5, the toner of each color superimposed on the surface of the recording paper is melted and fixed on the recording paper, and a full-color image is formed on the recording paper. The recording paper on which the full-color image has been fixed is separated from the pressure roller 52 by the separation claw 68 and discharged out of the apparatus.
[0028]
[ICC profile creation procedure]
When the user wants to know the color of the final output at the stage of designing the design, the user causes the printer to output a test form of ISO 12642 or the like in a mode in which color conversion is not performed as much as possible. Then, the color of each patch of the output test form is measured to obtain CIE (International Commission on Illumination) L * a * b * data. Note that the data may be CIE 1931 XYZ color system data in a device-independent color space.
[0029]
The method for calculating the L * a * b * data from the spectral reflectance data is defined by the CIE and is as follows.
(1) The spectral reflectance R (λ) of the sample is determined (380 to 780 nm).
(2) Prepare color matching functions x (λ), y (λ) and z (λ), and standard light spectral distribution SD50 (λ).
(3) Calculate each wavelength and integrate them.
{X (λ) = {R (λ) × SD50 (λ) × x (λ)}
{Y (λ) = {R (λ) × SD50 (λ) × y (λ)}
{Z (λ) = {R (λ) × SD50 (λ) × z (λ)}
Integration range is 380-780nm
(4) The product of the color matching function y (λ) of each wavelength and the standard light spectral distribution SD50 (λ) is integrated.
{SD50 (λ) × y (λ)}
Integration range is 380-780nm
(5) Calculate XYZ values.
X = 100 · {SD50 (λ) × y (λ)} / {X (λ)
Y = 100 · {SD50 (λ) × y (λ)} / {Y (λ)
Z = 100 · {SD50 (λ) × y (λ)} / {Z (λ)
(6) Convert to L * a * b * data.
L * = 116 · (Y / Yn) ^1/3 −16
a * = 500 · ｛(X / Xn) ^1/3 − (Y / Yn) ^1/3 ｝
b * = 200 ｛(Y / Yn) ^1/3 − (Z / Zn) ^1/3 ｝
Here, Xn, Yn and Zn are standard light tristimulus values.
In the case of Y / Yn> 0.008856
(X / Xn) ^1/3 = 7.78 (X / Xn) ^1/3 +16/116
(Y / Yn) ^1/3 = 7.78 (Y / Yn) ^1/3 +16/116
(Z / Zn) ^1/3 = 7.78 (Z / Zn) ^1/3 +16/116
[0030]
The test form of ISO 12642 includes CMYK color signal patches covering the color reproduction range that can be output by the printer, and the color signal value (CMYK) of each patch and the L * a * b * value of the colorimetric result. A color conversion table can be created from the relationship. That is, what CMYK signal should be output for the input chromaticity signal (L * a * b *), or what color (L * a * b *) the CMYK signal should reproduce It is possible to create a conversion table indicating whether the conversion is performed.
[0031]
[Structure of ICC profile]
FIG. 2 is a diagram showing the structure of the ICC profile, which includes two basic elements, a header 39 and a tag table 40. The header 39 includes information used by a CMM (Color Management Module) such as ColorSync (a color conversion engine of Apple Inc.) to process the input image data according to the ICC profile.
[0032]
The ICC profile includes a required public tag used during normal color conversion, an optional public tag that can be used for performing additional conversion, and an individual developer including the optional public tag. It may include a private tag that can be customized to add dedicated values to the ICC profile. In order to perform output color conversion for hard copy, a profile description tag, a device manufacturer tag, a device model name tag, an AtoBx tag, a BtoAx tag, a gamut tag, an XYZ media white point tag (XYZ medium white point tag), A measurement tag and a copyright tag are required. The AtoBx tag has either an ICC lut8Type or an ICC lut16Type structure. The general-purpose model of the ICC lut8Type or ICC lut16Type structure is as follows.
Matrix → One-dimensional LUT → Multi-dimensional LUT → One-dimensional LUT
[0033]
If the tag has a lut8Type structure, the input and output LUTs, as well as the color LUT, are arrays of 8-bit unsigned values. Each input table is composed of a one-byte integer. The entries of the input table are appropriately standardized in the range of 0 to 255, respectively.
[0034]
The AtoBx tag included in the ICC profile for the output device includes a color conversion table for converting from the CMYK color space to another color space, and is used as a so-called source (target) profile.
[0035]
On the other hand, the BtoAx tag for the output device has the reverse color conversion, includes information for converting from the Lab color space to the CMYK color space, and is mainly referred to when used as a destination profile.
[0036]
The tags AtoB0 and BtoA0 are tags for performing perceptual color conversion, and mainly perform color conversion suitable for a photographic image that emphasizes gradation (gradation) reproduction, and are premised on brightness preservation. For color matching.
[0037]
The AtoB1 and BtoA1 tags are for performing color conversion that minimizes the color difference. When the color reproduction range of the output device is wider than that of the target in all areas, and when there is no image in the high saturation area. It is effective for such as. In addition, this color matching is adopted for color reproduction of a logo mark such as a company emblem, because the color specification is strict.
[0038]
The tags of AtoB2 and BtoA2 are tags for performing color conversion for preserving saturation, and are not suitable for tone reproduction, but are mainly used for color matching of business graphic images.
[0039]
The gamut tag having the same format as the AtoB0 tag describes whether or not the output device can reproduce color for the input channel (L * a * b *).
[0040]
FIG. 3 is a diagram showing a detailed example of the ICC profile. The following items are described in the header 39 and the tag table 40.
Size: Defines the size of the profile.
CMM Type: Describes which CMM is used as a default by a computer incorporating a plurality of CMMs. For example, “Appl” or “ACMS” means the above-mentioned ColorSync, and “KCMS” means Kodak CMS (Kodak color conversion engine). Version: Indicates the version of the profile.
Profile Class: Defines the type of profile. The parameter may be any one of the following.
output… an output device such as a printer
input… input devices such as scanners and digital cameras
display ... Display devices such as CRTs and liquid crystals
device link ... Combination structure of multiple profiles
color space conversion: color space conversion between non-device type profiles, for example, Lab / XYZ
abstract ... A unique method for converting color data between PCS (Profile Connection Space).
Color Space: Defines a color format for converting color image data based on a profile, and is one of RGB, XYZ, GRAY (gray scale), CMY, Luv, HSV, CMYK, YCbr, HLS, Lab, and Yxy. Should be fine.
Connection Space: Defines a profile connection space, and may be either Lab or XYZ.
Creation Date: Defines the date and time when the profile was created.
CS2 Signature: Defines the file signature of the profile and is used by the operating system (OS) of the device using the profile to create the icon.
Prim platform: Defines the platform or OS on which the profile was created. The parameter may be any of the following.
Appl ... OS of Apple
MSFT… Microsoft OS
SGI… Silicon Graphics
SUNW… Sun
TGNT… Taligent
Flags: contains hint information for CMM. If "embedded / not embedded" is indicated, it indicates a profile / independent file embedded in an image file or the like, and if "embedded only / use anywhere" is indicated, it can be used only in the embedded state / can be used even if it is separated Represents
deviceManufacturer: describes the creator of the profile.
deviceModel: defines the model number or name of the device for which the profile is to be used. The parameters of the device model must conform to the rules of ICC, ColorSync of Apple, and ICM of Microsoft. In particular, the model number or name must be a 4-byte ASCII string using the characters "A" through "Z" (uppercase only) and the characters "0" through "9".
deviceAttributes: Describes the transparency and gloss of the surface when creating a profile. "Reflective / Transparency" (reflection color / transmission color), "Glossy / Matete" (glossy / matte), and the like are described.
Intent: Defines the profile's design intent, that is, perceptual, relative colorimetric or absolute colorimetric, and saturation.
White XYZ: Defines the XYZ chromaticity value of PCS, and describes a value obtained by normalizing white XYZ.
[0041]
As described above, the header 39 is not a list including all pieces of information that can be stored in the header, but merely shows an example of information that can be stored in the header. In order to create such an ICC profile, it is necessary to output an image covering the CMYK signals, such as a test form of ISO 12642, to a printer.
[0042]
[Overview of Embodiment]
In the embodiment, even if an image signal whose signal sum exceeds a predetermined value (for example, 300%) is input, the output condition is limited and the amount of gluing is limited so that the ICC profile can be created without any problem. Output without output. Further, when an image signal that is not a test form for creating the above ICC profile and a sum signal corresponding to a region having a predetermined area or more exceeds a predetermined value is input, the amount of gluing is forcibly limited, and To execute the toner reduction.
[0043]
[Restriction of glue amount]
Hereinafter, a printer in which the maximum amount is specified to be 300% will be described as an example. The maximum amount varies depending on the toner material, transfer conditions, fixing conditions, and the like, and is experimentally calculated. In addition, the paste amount 300% is 1.50 mg / cm. ² And the amount of paste at the maximum density (Dmax) portion of a single color is 0.50 mg / cm. ² It is.
[0044]
The maximum amount is determined in consideration of the following. (1) Tolerable limit of toner scattering in the transfer unit, (2) Jam (paper jam) due to wrapping of the recording paper in the fixing unit, (3) Recording paper due to forced separation of the recording paper in the fixing unit Consider the uneven gloss at the leading edge and (4) the occurrence of an unfixed image due to a temperature drop during continuous paper feeding. The toner scattering in (1) particularly affects an image having sharp edges, but slightly degrades the image quality.
[0045]
On the other hand, items (2) to (4) relating to the fixing unit are problems of image quality defects such as interruption of the printing operation and gloss unevenness or unfixed.
[0046]
That is, the biggest reason for limiting the amount of gluing is to interrupt the printing operation, in other words, to set a good output image without interrupting the user's work. Since a table for forming an image by limiting the maximum amount of glue is stored in a color conversion profile in a printer described later, there is no problem in normal image output. However, when the above-mentioned ICC profile is created, it is desirable not to perform color conversion by a printer. In fact, a high-end color copier or color printer has a mode for bypassing this color conversion.
[0047]
When the printer is provided with the bypass mode and an image signal whose signal sum exceeds 300% is input in a state where the bypass mode is set, the above-described problem occurs. Therefore, in the present embodiment, in the bypass mode, input image data is analyzed to determine the occurrence of the above-described problem. Then, when it is determined that a problem occurs, toner reduction is performed, and when it is determined that no problem occurs, toner reduction is not performed.However, in order to prevent occurrence of unfixed due to a decrease in fixing temperature, continuous output is performed. Restrict.
[0048]
[Image processing unit]
FIG. 4 is a block diagram illustrating a configuration example of the image processing unit.
[0049]
The image processing unit is connected to a scanner 100 as an image input device and a printer 200 as an image output device via a device interface (I / F) 2020, while being connected via a network interface card (NIC) 2010. Connected to a network such as a LAN to input and output image information and device information.
[0050]
The CPU 110, which controls the entire printer including the image processing apparatus, controls the printer based on firmware, system software, and control software stored in the ROM 111 and the hard disk drive (HDD) 115 using the RAM 112 as a work memory. And various image processing and communication processing. Note that the HDD 115 can spool image data input from the scanner 100 or the network or store output image data.
[0051]
The CPU 110 outputs an image to be displayed on the operation unit 2012 to the operation unit 114 via the operation unit I / F 2006, and inputs operation information indicating a user instruction from the operation unit 114 via the operation unit I / F 2006. I do.
[0052]
The bus bridge 2005 is a conversion bridge that interconnects a system bus 2007 to which the CPU 110 and the like are connected and an image bus 2008 that transfers image data at high speed. The image bus 2008 is configured by a PCI (Peripheral Component Interconnect) bus or a serial bus such as IEEE1394.
[0053]
The RIP 2060 connected to the image bus 2008 develops a page description language (PDL) code into a bitmap image. The device I / F 2020 connects the scanner 100 and the printer 200, which are image input / output devices, and performs synchronous / asynchronous conversion of image data transfer. The scanner image processing unit 2080 performs correction, processing, and editing processing on input image data. The scanner image processing unit 2080 performs shading correction, input masking processing, and the like on the RGB signals input from the scanner 100, and further depends on the RGB signals depending on devices. Is converted into a signal of a color space (for example, L * a * b *). The printer image processing unit 2090 performs, for example, L * a * b * → CMYK conversion on image data to be output to the printer 200, and further performs output masking processing, gradation correction, filter processing, resolution conversion, and the like on the CMYK signal.
[0054]
As described above, the image data transferred on the image bus 2008 includes RGB data, L * a * b * data, CMYK data, and the like. Note that the color conversion profile for performing the L * a * b * → CMYK conversion is created under the condition that the maximum output color number is limited and the signal sum is 300% or less.
[0055]
The CMYK color conversion unit 24 determines that the CMYK image data input from the PC or the like targets any of Japan Color, DIC, TOYO, EURO Standard, SWOP, Pantone, and custom (a target profile is downloaded by the user). Then, the CMYK image data is converted from CMYK to L * a * b * and passed to the printer image processing unit 2090 so as to simulate the color of the printing ink registered in advance.
[0056]
The RGB color conversion unit 21 determines that the RGB image data input from a PC or the like targets any one of sRGB, monitor RGB, Apple RGB, and custom (a target profile is downloaded by a user), and converts the RGB image data to RGB → L * a * b * conversion and transfer to the printer image processing unit 2090.
[0057]
In the case of CMYK image data that is input from a PC or the like and does not execute the above ink color simulation (in other words, does not perform color conversion processing, that is, does not specify a simulation that is color processing), the CPU 110 determines the amount of glue The unit 22 is made to analyze the CMYK image data to determine the amount of application, and to determine whether to form an image as it is or to perform toner reduction. If it is determined that toner reduction is to be performed, the CPU 110 transmits the toner reduction to a client (PC) or the like, which is the transmission source of the CMYK image data, via the NIC 2010 in order to notify the user of the toner reduction. Notify execution. When the determination (and toner reduction) of the glue amount determination unit 22 ends, the CPU 110 supplies the CMYK image data to the printer image processing unit 2090 to execute only the monochrome tone correction.
[0058]
The printer according to the embodiment has a characteristic that the amount of application is linear with respect to the image signal, as shown in FIG. Therefore, it is possible to perform control by judging that the signal sum is information indicating the amount of application.
[0059]
[Glue amount judgment unit]
FIG. 6 is a block diagram showing a configuration example of the paste amount determining unit 22. The paste amount determining unit 22 sequentially performs the following processing.
(1) In a predetermined area (for example, an area 100 mm from the front end) of the front end of the recording paper, is there a signal sum exceeding 300% for each pixel?
(2) How many pixels whose signal sum exceeds 300% exist in the above area.
(3) Perform toner reduction as required.
[0060]
The image signal integrator 301 calculates the signal sum of each pixel, and outputs a signal indicating a pixel whose image signal exceeds 300% as “1” and a pixel not exceeding 300% as “0”.
[0061]
Based on the signal input from the image signal accumulating unit 301, the area determination unit 302 determines the determination area of the leading edge of the recording paper (the area 100 mm from the leading edge, the A4 length, the non-printable area is 2 mm, and the area is 98 × 25.4 mm). The ratio (existence rate) of pixels exceeding 300% existing in the area, 2314 × 6921 pixels in 600 dpi conversion, is calculated. If the determination area is 2314 × 6921 pixels under the above condition, the existence ratio is represented by the following equation. It goes without saying that the denominator of the following equation changes according to the recording paper size, portrait or landscape, and margin size.
Existence rate = Number of pixels exceeding 300% / (2314 × 6921) × 100%
[0062]
The toner reduction execution determination unit 303 determines whether or not the presence ratio exceeds a determination threshold (for example, 10%), which is derived from the fixing condition and is set by the CPU 110 as setting information, and the presence ratio exceeds the determination threshold. In this case, a toner reduction ON signal is sent to the toner reduction unit 304. If the signal does not exceed the toner reduction ON signal, a toner reduction OFF signal is sent.
[0063]
When the toner reduction signal is on, the toner reduction unit 304 performs toner reduction on the CMYK image signal. Note that a buffer is provided for holding the input CMYK signal until the determination is completed. The toner reduction is performed by a method that maintains the black (K) component and maintains the gradation and the hue as much as possible. The following equation shows the relationship.
When C + M + Y + K> 300,
K '= K
n = 300−K ′
C ′ = C / (C + M + Y)
M ′ = M / (C + M + Y)
Y '= Y / (C + M + Y)
At this time, C ′ + M ′ + Y ′ = 100
nC ′, nM ′, nY ′ and K ′ are signals after toner reduction
[0064]
[processing]
FIG. 7 is a flowchart illustrating an example of the image forming process of the CPU 110, which is a process executed when printing is instructed via a network.
[0065]
First, it is determined whether a target is specified in the input image data (S101).
[0066]
In other words, CMYK image data targeting any of Japan Color, DIC, TOYO, EURO Standard, SWOP, Pantone, and Custom for simulating the color of the printing ink described above, or sRGB, monitor RGB, AppleRGB, It is determined whether or not RGB image data targeting any of the custom is input. If the target is specified, a target simulation (CMYK or RGB → L * a * b * conversion) is performed (S102), and the L * a * b * data is converted into CMYK data of the printer (S103). Then, printing is executed (S104). Then, it is determined whether or not the designated number has been printed (S105), and when the designated number has been printed, the process is terminated.
[0067]
On the other hand, if the target image data is not specified, it is determined whether the target image data is RGB image data (S111). If the target image data is RGB image data, sRGB is set as a target (S112), and a target simulation is performed (S102). ). If the image data is not RGB image data, it is determined whether or not the image data is CMYK image data (S113). If the image data is not CMYK image data, L * a * b * data is required, so that a target simulation is unnecessary, and L * a * b * Convert the data into CMYK data of the printer (S103).
[0068]
In the case where no target is specified and CMYK image data is used, as in the case of patch printing for creating an ICC profile, the glue amount determination unit 22 is started to determine whether to perform toner reduction, and the CMYK image data Is supplied (S114), and the determination result of the glue amount determination unit 22 is determined (S115). If toner reduction is performed, printing is performed (S104). If toner reduction is not performed, it is determined whether or not the number of prints is plural (S116). If it is single (one), printing is performed (S104). . When the number of prints is plural, continuous output is not performed in order to prevent output of an unfixed image due to a decrease in fixing temperature due to continuous output as described in JP-A-2000-330413 (output environment limitation). ), Printing is performed in the intermittent mode (S117). Printing in the intermittent mode is a mode in which thinning-out output is performed without changing the output speed in order to suppress the influence of a decrease in fixing temperature. Then, it is determined whether or not the specified number has been printed (S118), and when the specified number has been printed, the process is terminated. The printing in the intermittent mode is executed by instructing the control unit of the printer 200 from the CPU 110.
[0069]
As described above, the input image data is analyzed, and when the amount of application exceeds the limit, toner reduction is performed, or printing is performed in the intermittent mode in which continuous output is not performed without performing toner reduction. Therefore, it is possible to prepare an effective image output environment, for example, when creating an ICC profile to grasp the device color. Further, since toner reduction is performed under image conditions such as when a target simulation is performed, jamming and unfixed toner in the fixing unit 5 can be prevented in normal printing.
[0070]
[Second embodiment]
Hereinafter, an image processing apparatus according to a second embodiment of the present invention will be described. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.
[0071]
In the first embodiment, the predetermined area at the leading end of the recording paper is set as the area for determining whether the toner reduction is necessary. However, in the second embodiment, the predetermined area at the rear end of the recording paper is also determined as the necessity of the toner reduction. Make the area to be determined. In other words, the necessity of toner reduction is determined in the determination region at the leading end, and if it is determined that toner reduction is necessary, the necessity of toner reduction is determined in the determination region at the rear end. If it is determined that toner reduction is unnecessary at the trailing edge, the image is rotated by 180 degrees and the lower part of the image is printed on the leading edge of the recording paper. This is because it is not necessary to print an ICC profile or the like by distinguishing the leading and trailing ends of the recording paper. Of course, if both determinations require toner reduction, the same processing as in the first embodiment is performed.
[0072]
FIG. 8 is a block diagram illustrating a configuration example of a glue amount determination unit according to the second embodiment. In order to determine the necessity of toner reduction at the top and bottom of the image, a page memory unit 305 that holds the input CMYK image data for one page is required. When the image is rotated by 180 degrees without performing the toner reduction, the toner reduction execution determination unit 303 sends a toner reduction off signal to the toner reduction unit 304 and sends a rotation on signal to the page memory unit 305. The page memory unit 305 that has received the rotation-on signal reads out and outputs image data from the rear end of the image stored in the memory.
[0073]
[Third embodiment]
Hereinafter, an image processing apparatus according to a third embodiment of the present invention will be described. In the third embodiment, the same components as those in the first and second embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted.
[0074]
If there is a certain amount of pixels (for example, 10%) at the leading end of the recording paper that exceeds 300%, the winding of the recording paper in the fixing unit 5 is likely to occur. If there is no pixel whose glue amount exceeds 300%, no problem occurs. Therefore, in the third embodiment, the timing of reading image data from the memory is controlled, in other words, based on the result of moving the determination area and determining whether toner reduction is necessary, if possible, the designated recording paper By using a recording paper larger than the size, or by enlarging the margin at the leading end of the recording paper, the winding of the recording paper is suppressed.
[0075]
FIG. 9 is a flowchart showing a process in the third embodiment, which is a process executed between steps S114 and S115 shown in FIG.
[0076]
The CPU 110 determines the determination result of the applied amount determination unit 22 (S201), and terminates this processing if “toner reduction is unnecessary”. If “toner reduction is required”, an instruction to delay reading of the image data by 10 mm of the recording paper is sent to the page memory unit 305 of the glue amount determination unit 22 (S202), and the toner reduction necessity is sent to the glue amount determination unit 22. A decision is made (S203). The page memory unit 305 outputs a CMYK image signal whose signal value is all zero for 10 mm (236 lines in the case of 600 dpi) according to the instruction, and then outputs the CMYK image data held in the page memory.
[0077]
The CPU 110 again determines the determination result of the glue amount determination unit 22 (S204), and instructs the glue amount determination unit 22 to shift-output the image data if “toner reduction is unnecessary” (S212). The page memory unit 305 instructed to perform the shift output outputs the image data with the set delay amount in the same manner as described above.
[0078]
If "toner reduction is required", it is determined whether or not the amount of delay in reading image data (delay amount) is less than 190 mm (S205). If less than 190 mm, whether or not the image protrudes from the recording paper is determined. It is determined (S206), and if it does not protrude, an instruction to increase the delay amount by 10 mm is sent to the page memory unit 305 (S207), and the process returns to step S203. That is, the processing of steps S203 to S207 is repeated until it is determined that "toner reduction is unnecessary", the delay amount becomes 190 mm or more, or the image runs off the recording paper.
[0079]
Note that, since the margin width is defined as 100 mm and the range of 10%, the delay amount is limited to 190 mm (the strictly calculated portion is 188 mm (considering the non-printable area 2 mm)). Under such conditions, no problems occurred in the printer tested.
[0080]
If it is determined that the delay amount becomes 190 mm or more or the image protrudes from the recording paper, the CPU 110 instructs the printer 200 to enlarge the recording paper size (S208), and determines whether there is a response of “recording paper present”. Is determined (S209). For example, when the designated size is A4, if recording paper of A3 or B4 is stored, the printer 200 returns “recording paper present”, but if only recording paper of A4 or smaller is stored, “no recording paper” is displayed. returned.
[0081]
When “no recording paper” is returned from the printer 200, the CPU 110 instructs the output determining unit 22 to output the toner-reduced image data (S210). When "recording paper present" is returned, the output of the image data shifted to the center of the recording paper is instructed to the amount-of-paste determining unit 22 (S211). The page memory unit 305 instructed to perform the shift output reads out the image data stored in the page memory so as to output image data in which a margin for the enlargement of the recording paper is added around the image.
[0082]
As described above, according to the third embodiment, in addition to the determination of the necessity of the toner reduction at the upper part and the lower part of the image described in the second embodiment, the relative position between the recording sheet and the image is shifted, and Since the enlargement of the recording paper is taken into consideration, the possibility that image data which had to be reduced by toner in the first and second embodiments can be printed without toner reduction is increased, and processing suitable for investigating the color reproduction characteristics of the printer is performed. It can be carried out.
[0083]
In the third embodiment, the case where the reading of the image data is delayed with respect to the recording paper has been described. Can be determined. In this case, if it is determined that toner reduction is not necessary with a certain delay amount, the image data can be read upside down in the same manner as in the second embodiment, and with the delay amount, in the same manner as described above. Just fine.
[0084]
In some situations, enlargement of the margin is allowed, but enlargement of the recording paper may not be allowed due to the convenience of the colorimeter. Therefore, each of the above determinations may be turned on and off.
[0085]
Although the above description has been made on the assumption that the relationship between the amount of application and the image signal is linear, it is possible to cope with the case where the relationship between the amount of application of the printer and the image signal is not linear. For example, a conversion table of a glue amount for an image signal is prepared for each color component, and a glue amount is calculated by using a table (see FIG. 10) indicating what the image signal is for a certain glue amount. What is necessary is just to calculate the maximum amount of glue by making the relationship with the image signal linear.
[0086]
The horizontal axis in FIG. 10 is the image signal, and the vertical axis is the amount of the monochromatic toner applied to 0.5 mg / cm ² Is normalized to 100. The solid line in FIG. 10 shows the gradation characteristics of the printer, the broken line shows the inversely converted glue amount conversion table, and the two-dot chain line shows a target whose glue amount is linear with respect to the image signal. By converting an input image signal into glue amount information via this conversion table, the same processing as in the first to third embodiments can be performed. For example, the maximum amount of paste is 1.5 mg / cm ² In this case, the relationship that the image signal becomes 320% (300% when the amount of glue is linear) can be derived.
[0087]
[Other embodiments]
The present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), but can be applied to a device including one device (for example, a copier, a facsimile machine, etc.). May be applied.
[0088]
Further, an object of the present invention is to supply a storage medium (or a recording medium) in which a program code of software for realizing the functions of the above-described embodiments is recorded to a system or an apparatus, and a computer (or a CPU or a CPU) of the system or the apparatus. Needless to say, the present invention can also be achieved by an MPU) reading and executing a program code stored in a storage medium. In this case, the program code itself read from the storage medium realizes the function of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. When the computer executes the readout program code, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instruction of the program code. It goes without saying that a part or all of the actual processing is performed and the functions of the above-described embodiments are realized by the processing.
[0089]
Further, after the program code read from the storage medium is written into a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, the function is executed based on the instruction of the program code. It goes without saying that the CPU included in the expansion card or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.
[0090]
When the present invention is applied to the storage medium, the storage medium stores program codes corresponding to the flowcharts described above.
[0091]
【The invention's effect】
As described above, according to the present invention, image processing in consideration of printing of a color test chart is realized.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of a color copying machine;
FIG. 2 is a diagram showing a structure of an ICC profile;
FIG. 3 is a diagram showing a detailed example of an ICC profile;
FIG. 4 is a block diagram illustrating a configuration example of an image processing unit.
FIG. 5 is a diagram showing an example of a relationship between an image signal and a glue amount;
FIG. 6 is a block diagram illustrating a configuration example of a glue amount determination unit;
FIG. 7 is a flowchart illustrating an example of an image forming process of a CPU;
FIG. 8 is a block diagram illustrating a configuration example of a glue amount determination unit according to the second embodiment;
FIG. 9 is a flowchart showing processing according to the third embodiment;
FIG. 10 is a diagram illustrating a conversion table between a glue amount and a signal value.

Claims (17)

Input means for inputting image data indicating a mixed state of a plurality of color materials;
Analysis means for analyzing the usage of the color material from the input image data,
Setting means for setting output conditions based on the analysis result;
Forming means for forming an image based on the input image data on a recording medium based on the set output condition. The output condition is at least one of an output speed or an output interval of a recording medium on which an image is formed, a limitation on a usage amount of the coloring material, an image orientation during image formation, a size of the recording medium, and a fixing condition. The image processing apparatus according to claim 1, wherein: Control means for analyzing input image data and instructing processing to be performed on the input image data;
Processing means for performing an instructed process on the input image data;
Output means for outputting the input image data to a printing device,
The image processing apparatus according to claim 1, wherein the control unit, when the input image data indicates printing without color processing designation, instructs a process according to a usage amount of the color material. An analysis unit configured to analyze the input image data to determine a usage amount of the color material on a pixel-by-pixel basis when the processing unit is instructed to perform a process according to the usage amount of the color material; Determining means for determining whether to limit the usage of the color material in accordance with the usage of the material, and limiting the usage of the coloring material to the input image data in accordance with the determination result of the determination means The image processing apparatus according to claim 3, further comprising a restriction unit that performs a process of performing the processing. The analysis means calculates a sum of image data of each color corresponding to each pixel, and outputs information indicating a pixel whose sum exceeds a predetermined value as information corresponding to the usage amount of the color material. The image processing device according to claim 4. 5. The image processing apparatus according to claim 4, wherein the determination unit performs the determination based on an abundance rate of pixels whose sum exceeds a predetermined value in a determination area corresponding to a vicinity of a leading end of the recording paper. 6. apparatus. 5. The determination unit according to claim 4, wherein the determination unit performs the determination based on an abundance rate of pixels in which the sum exceeds a predetermined value in a determination area corresponding to a vicinity of a leading end and a trailing end of the recording paper. Image processing device. The processing unit is held in the page memory when the determination result near the front end of the determination unit indicates that the restriction process is performed, and when the determination result near the rear end indicates that the restriction process is not performed, 8. The image processing apparatus according to claim 7, wherein a process of sequentially reading the input image data from data corresponding to a rear end of a page is executed. The processing unit further includes a first conversion unit configured to convert the input image data into image data in a device-independent color space based on a target specified by the input image data, and a device-independent color space 9. The image processing apparatus according to claim 4, further comprising a second conversion unit configured to convert the image data into image data in a color space of the printing apparatus. The control unit may be configured such that the input image data indicates printing of a color material test chart, the determination result of the determination unit indicates that the restriction process is not performed, and the input image data indicates a plurality of printed sheets. The image processing apparatus according to any one of claims 4 to 9, further comprising: instructing the printing apparatus to perform an intermittent printing mode. 10. The control device according to claim 4, wherein the control unit instructs the determination unit to move and re-determine the determination area when the determination result of the determination unit indicates that the restriction process is performed. An image processing apparatus according to claim 1. The control means instructs the processing means to shift and output the input image data held in a page memory when the re-determination result of the determination means indicates that the restriction processing is not performed. An image processing apparatus according to claim 11. When the re-determination result of the determination unit indicates the execution of the restriction process, the control unit instructs the printing apparatus to enlarge a recording medium, and performs the shift output of the input image data held in a page memory in the processing unit. The image processing apparatus according to claim 11, wherein instructions are given to a means. Input image data indicating the mixed state of multiple color materials,
Analyze the usage of the color material from the input image data,
Set output conditions based on the analysis results,
An image processing method, wherein an image based on the input image data is formed on a recording medium based on set output conditions. Analyze the input image data, determine the processing to be performed on the input image data,
Applying the determined processing to the input image data,
Having each step of outputting the input image data to a printing device,
When the input image data indicates the printing of a color test chart, a process according to the used amount of the color material is determined. A program for controlling an image processing apparatus to execute the image processing according to claim 14. A recording medium on which the program according to claim 16 is recorded.

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