JP2004037525A - Image processing device and control device, and methods thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that gloss information is not effectively utilized though an ICC profile includes rough gloss information showing "glossy/matted" as attribute information. <P>SOLUTION: When the gloss information of a target profile shows "glossy" (S11)" and if glossy paper is housed in a paper supply cassette (S13), an image is formed (S14) by performing color conversion in a gloss mode. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image processing device, a control device, and a method thereof, for example, to an image processing in consideration of glossiness of an image.
[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]
Furthermore, in order to realize remote proofing and cluster printing for outputting images whose colors have been adjusted by the designer at each site, a new image forming apparatus that connects a plurality of image forming apparatuses to a network server and outputs the images. The use of is becoming widespread.
[0006]
In the color conversion processing of the image forming apparatus, the RGB signals input from the scanner are LOG-converted into CMY signals, the CMY signals are subjected to UCR processing to generate a K (black) component, and the CMYK signals are obtained. . Color conversion between device-dependent color spaces, such as from RGB of a scanner to CMYK of a printer, is not a problem in a closed image forming environment such as a copier, but the color space of signals input to the MFP varies. In the above method, color matching cannot be performed at all. Therefore, the method of converting an input signal into a device-independent color space (for example, CIE Lab) using the mechanism of the ICC profile, and further converting the input signal into a signal in a printer color space using the ICC profile of the image has been proposed. It has also been adopted for color conversion processing of a forming apparatus. It is easy to download an ICC profile to such an image forming apparatus. For example, the latest ICC profile is sequentially downloaded in order to minimize a color change due to durability deterioration.
[0007]
[Problems to be solved by the invention]
Since the ICC profile describes information for accurately mapping color information to another device or to a color space independent of a device, color matching has a reputation. However, it is not only colors that affect the impression of the output image. In particular, glossiness is closely related to color, and glossiness often affects appearance such as realism and luxury. The ICC also recognizes the importance of glossiness, and the ICC profile includes rough glossy information of “glossy / matte” as attribute information, but this information is not used effectively.
[0008]
In addition, despite the fact that the ICC profile for glossy paper is selected and color-converted, plain paper is often selected in the output settings, a function to prevent this, and a function to automatically select recording paper Function is desired.
[0009]
SUMMARY An advantage of some aspects of the invention is to solve the above-described problems individually or collectively, and to control image formation according to gloss information described in a profile.
[0010]
It is another object of the present invention to control image formation in accordance with gloss information described in a profile and the type of recording paper usable for image formation.
[0011]
It is another object of the present invention to store a profile with an accurate description.
[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 is an image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space. An acquisition unit for acquiring the described gloss information and a control unit for controlling image formation based on a comparison result between the gloss information and the set image forming mode are provided.
[0014]
An image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space, and obtains gloss information described in the profile Acquiring means for detecting the type of recording medium that can be used for image formation, determining a recording medium and an image forming mode to be used for image formation based on the gloss information and the type of the recording medium, Control means for controlling the formation.
[0015]
An image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space. Target glossiness information described in a profile related to color conversion to a color space independent of color, and a destination described in a profile related to color conversion from a color space independent of the device to a color space unique to the device. Acquisition means for acquiring the gloss information of the target, and control means for determining a recording medium and an image formation mode to be used for image formation based on a comparison result of the gloss information of the target and the destination, and controlling image formation. It is characterized by having.
[0016]
An image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space. Acquisition means for acquiring gloss information of a target described in a profile relating to color conversion to a color space independent of color, detection means for detecting glossiness of a recording medium usable for image formation, glossiness of the target A control unit that determines a recording medium to be used for image formation, an image forming mode, and a destination profile based on the information and the comparison result of the glossiness of the recording medium, and controls image formation.
[0017]
Also, an image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space, wherein the memory stores the profile, Control means for determining the description of the gloss condition of the profile to be stored in the memory and controlling storage of the profile based on the determination result.
[0018]
The control method according to the present invention is a control method for an image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space, It is characterized in that gloss information described in a profile is obtained, and image formation is controlled based on a result of comparison between the gloss information and a set image forming mode.
[0019]
A method for controlling an image processing apparatus for performing color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space, wherein the glossiness described in the profile is described. Information, detecting the type of recording medium that can be used for image formation, determining the recording medium and image forming mode to be used for image formation based on the gloss information and the type of recording medium, and controlling image formation. It is characterized by doing.
[0020]
A method for controlling an image processing apparatus for performing color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space, the method comprising: Target glossiness information described in a profile related to color conversion from the device to the device-independent color space, and described in a profile related to color conversion from the device-independent color space to a device-specific color space. Acquiring the destination gloss information, determining a recording medium and an image forming mode to be used for image formation based on a comparison result of the target and destination gloss information, and controlling image formation. I do.
[0021]
A method for controlling an image processing apparatus for performing color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space, the method comprising: To obtain the target gloss information described in the profile regarding the color conversion to the device-independent color space, detect the gloss of the recording medium that can be used for image formation, the target gloss information and the It is characterized in that a recording medium, an image forming mode, and a destination profile to be used for image formation are determined based on a comparison result of glossiness of the recording medium, and image formation is controlled.
[0022]
A method for controlling an image processing apparatus for performing color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space, wherein the memory stores the profile It is characterized in that the description of the gloss condition of the profile to be stored is determined, and the storage of the profile is controlled based on the determination result.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, image processing according to an embodiment of the present invention will be described in detail with reference to the drawings.
[0024]
[ICC profile]
FIG. 1 is a diagram illustrating color conversion using an ICC profile.
[0025]
The CMM (Color Matching Module) 102 refers to the ICC profile 104 of the input device 101 and converts the RGB image data of the color space dependent on the input device 101 into the Lab (Label) of the color space (PCS: Profile Connection Space) independent of the device. Or XYZ) data, perform color space compression (gamut mapping) as necessary, and further refer to the ICC profile 105 of the output device 103 to convert Lab data to CMYK in a color space dependent on the output device 103. Convert to data. Of course, color conversion in the reverse direction is also possible. Thus, the CMM uses an ICC profile to perform color conversion between two device dependent color spaces.
[0026]
Thus, the ICC profile provides the CMM 102 with color conversion information for a particular device. More specifically, an ICC profile is provided for each device (or each recording paper), converts color image data from a device-dependent color space to a PCS, and further converts a color image data from the PCS to another device. Used by the CMM 102 when converting to space.
[0027]
FIG. 1 shows ICC profiles 104 and 105 corresponding to an input device 101 such as a scanner and an output device 103 such as a printer, but these ICC profiles are not necessarily incorporated in the devices. These ICC profiles may be embedded in data to be subjected to color conversion by the CMM (image data such as TIFF), or may be stored in a memory of a computer device that executes the CMM. Further, the ICC profile can be applied to an image input / output device such as a digital camera, a monitor, and a color facsimile machine in addition to a scanner and a printer.
[0028]
Meanwhile, the PCS defines a D50 standard light source, CIE Lab or XYZ chromaticity coordinates as a uniform color space, and also defines 0/45 or 45/0 reflectance measurement for colorimetric conditions.
[0029]
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 contains information used by a CMM, such as ColorSync (a color conversion engine from Apple) to process the input image data according to the ICC profile.
[0030]
The ICC profile includes a required public tag designed to provide a complete set of information necessary for the CMM to convert color information between the PCS and the device-dependent color space. It is included. In addition, ICC profiles include optional public tags that can be used to perform additional conversions, and private tags that can be customized by individual developers to add proprietary values to the ICC profile. May be included.
[0031]
To perform color conversion of input data, a profile description tag, a device maker tag, a device model name tag, a media XYZ white point tag, a UCCMS private information tag, a copyright tag, and a relative XYZ of each of RGB are used. Color material tags containing tristimulus values, gamma tags for the R (red) channel, the G (green) channel, and the B (blue) channel are required.
[0032]
To perform color conversion for screen display, a profile description tag, a device manufacturer tag, a device model name tag, a media XYZ white point tag, a copyright tag, a color material tag including relative values such as RGB phosphors, Gamma tags for channels, G channels and B channels are required.
[0033]
To perform output color conversion for hard copy, a profile description tag, device manufacturer tag, device model name tag, AtoB0 tag, BtoA0 tag, gamut tag (gamuttag), AtoB1 tag, BtoA1 tag, AtoB2 tag, BtoA2 tag, UCCMS private Information tags, XYZ media white point tags, measurement tags, copyright tags, etc. are required.
[0034]
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
[0035]
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.
[0036]
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.
[0037]
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.
[0038]
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.
[0039]
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.
[0040]
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.
[0041]
The gamut tag is a one-input one-output one-dimensional look-up table (LUT) that describes whether or not the output device can be reproduced with respect to the input channel (Lab). It has the same format as the AtoB0 tag.
[0042]
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 / Matte" (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.
[0043]
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.
[0044]
The tag table 40 includes a list of tags and information on those tags, for both public tags and private tags. As mentioned earlier, public tags define normal color conversion operations that can be used in all ICC profiles. An example of a public tag defined in the tag table 40 is AtoB2 including two sets of 3 × 3 color conversion matrix processing, a three-dimensional LUT, and three one-dimensional LUTs. Other examples of public tags are described in more detail in the ICC profile format document.
[0045]
[First Embodiment]
[Constitution]
FIG. 4 is a diagram showing a schematic configuration of a color copying machine.
[0046]
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.
[0047]
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.
[0048]
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.
[0049]
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.
[0050]
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.
[0051]
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.
[0052]
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.
[0053]
The document reading section 7 optically scans the document placed on the document table to read the image of the document, and outputs image signals of RGB colors. An operation unit 300 having a display such as an LCD and ten keys is used for setting a color copying machine, inputting a command, setting the color copying machine, and displaying an operation state.
[0054]
[Image processing unit]
FIG. 5 is a block diagram illustrating a configuration example of a color conversion unit (part of an image processing unit) in a color copying machine. Note that the processing of the color conversion unit differs depending on the type of signal input from the interface (I / F) 202, and therefore will be described for each type of signal.
[0055]
When an RGB signal is input, the ICC profile of the input device stored in the input profile storage unit 201 is referred to. The input profile storage unit 201 stores target input ICC profiles such as sRGB, Apple RGB, CIE RGB, and NTSC (1953). The CMM 202 converts an input RGB signal into a Lab signal using a profile designated by the user from the input profiles.
[0056]
When the Lab signal is input, the CMM 202 converts the Lab signal into a CMYK signal with reference to an output profile corresponding to a predetermined mode stored in the output profile storage unit 203. The converted CMYK signal is sent to the printer unit 204.
[0057]
When a CMYK signal is input in addition to creating an ICC profile of a device, the target ICC profile stored in the target profile storage unit 205 is referred to. The target profile storage unit 205 stores target profiles such as SWOP Coated, EURO Standard, DIC (Dainippon Ink), TOYO (Toyo Ink), Japan Color, and various custom DDCPs. The CMM 202 converts an input CMYK signal into a Lab signal using a profile designated by a user from these profiles.
[0058]
When a CMYK signal indicating that the color reproduction characteristic of the printer is to be understood to create an ICC profile, or that the color has been converted by a computer device is input, there is no point in further color conversion. Bypassing, the CMYK signal is sent to the printer unit 204 as it is.
[0059]
The ICC profile can be downloaded to each profile storage unit in a timely manner in consideration of a change in color due to durability deterioration (change over time) such as deterioration of the developer and the fixing roller 51.
[0060]
The gloss condition comparison unit 206 of the image processing unit and the paper type detection unit 207 of the printer unit 204 are used in a gloss mode described later.
[0061]
[control]
The CPU 210 shown in FIG. 5 controls the entire color copying machine using the RAM 212 as a work memory according to a control program stored in the ROM 211. Further, it is determined whether the description of an ICC profile for a gloss mode described later is accurate, and whether or not recording paper is stored in a paper feed cassette 61 or the like in order to form an image corresponding to the gloss condition of the specified ICC profile. judge. If there is no recording paper corresponding to the gloss condition, the CPU 210 performs control such as displaying an error on the operation unit 300 or changing the fixing condition as an alternative.
[0062]
[Judgment of ICC profile]
The ICC profile in the initial state of the printer is provided by a device maker. However, the profile provided by the device maker is standard color conversion information, and the possessed device does not always have standard characteristics. For this reason, users who attach importance to color matching, for example, in the design and printing industries, can use a commercially available ICC profile creation software or an ICC profile creation service provided by a device maker or a software maker to perform more accurate color matching. Try to get. The color copying machine of the present embodiment can also download an ICC profile prepared by the user to each profile storage unit in consideration of such a user.
[0063]
The color copying machine of the present embodiment is provided with two image output modes: a normal mode and a glossy mode. The gloss mode is an image forming mode in which fixing conditions and recording paper conditions are set in order to improve the glossiness of an output image. If the gloss of the image changes, the color also changes. Therefore, the output profile storage unit 203 stores ICC profiles corresponding to each mode. Therefore, when downloading the ICC profile to the output profile storage unit 203, the ICC profile corresponding to each mode must be downloaded. In particular, if an ICC profile created based on a color patch formed on high-quality paper is downloaded as a gloss mode ICC profile, the effect of the gloss mode is not exhibited.
[0064]
FIG. 6 is a flowchart showing the ICC profile determination process, which is a process executed by the CPU 210 when the ICC profile is downloaded to the output profile storage unit 203.
[0065]
When the download of the gloss mode ICC profile is instructed, the CPU 210 refers to the attribute information (Attributes) of the ICC profile and determines whether or not the gloss condition is described as “glossy” (Glossy). It confirms (S1), and if “glossy”, the downloaded ICC profile is registered in the output profile storage unit 203 (S2). On the other hand, if it is "matte" (Matte), an error message to the effect that "registration is not possible" is displayed on the operation unit 300, and the registration work is stopped (S3).
[0066]
Further, if there is no description relating to the gloss condition, a message indicating "Is this ICC profile created using glossy paper?" Is displayed on the operation unit 300 to confirm with the user (S4). ), And waits for a response from the user (S5). If the user's response indicates YES, "glossy" is described as the gloss condition of the profile (S6) and registered in the output profile storage unit 203 (S2). If NO, the downloaded profile is discarded, and the registration operation is stopped (S7).
[0067]
When the profile is downloaded from the computer device via the network, it goes without saying that an error or an inquiry is transmitted to the computer device via the network and a response from the computer device is waited.
[0068]
[Gloss control]
Japanese Patent Application Laid-Open No. Hei 2-132481 discloses a technique for acquiring paper type, in particular, paper thickness information from a paper supply unit, and controlling the fixing temperature and pressure or the paper transport speed based on the paper type information. It is an invention to disclose and solve the problems of defective fixing and heat source capacity by such a configuration. As a method of detecting a paper type, a method based on recording paper density disclosed in JP-A-7-234610, a method based on spectral reflectance disclosed in JP-A-9-114267, and a method based on spectral reflectance disclosed in JP-A-9-114267. There is a method using specularly reflected light and irregularly reflected light disclosed in 198093.
[0069]
Further, Japanese Patent Application Laid-Open No. 7-191510 proposes a method in which a sensor for paper type (paper thickness) information is not provided and a user inputs paper type information from an operation unit. This method is currently the mainstream in image forming apparatuses. In the color copying machine of the present embodiment as well, the provision of the information on the paper thickness is basically performed by the user operating the operation unit 300 to input. The paper weight is written on a package that wraps the recording paper, and it is easy for the user to specify the paper weight via the printer driver or the operation unit 300. Therefore, the paper thickness and paper weight are detected. It is preferable to reduce the cost by removing the sensor for the purpose. Of course, such a sensor may be mounted to detect the paper thickness and paper weight.
[0070]
The fixing control based on the sheet thickness is sufficiently effective to prevent a so-called high-temperature offset in which an unfixed image or a toner image is peeled off from a recording sheet and adheres to a fixing roller.
[0071]
On the other hand, Japanese Patent Application Laid-Open No. 9-160315 discloses a method of controlling glossiness (gloss control) by changing the fixing speed, pressure, oil application amount, and the like. However, as shown in FIG. 7, a change in glossiness with respect to density occurs. In other words, in the case of the electrophotographic system employing the area gradation, only the control of the fixing device 5 can increase the glossiness of the high-density area where the toner is sufficiently loaded, but can change from the highlight area to the halftone area. The glossiness of the area is affected by the gloss characteristics of the recording paper. Therefore, a recording paper having a rough surface such as high-quality paper will have a gloss characteristic as shown in FIG. In order to avoid such glossiness characteristics, it is most efficient and effective to use a recording paper whose surface is not rough, such as coated paper.
[0072]
Therefore, in the present embodiment, a gloss sensor 16 as shown in FIG. 8 is installed in the paper feed unit to determine whether or not recording paper matching the gloss mode is stored in the paper feed cassette 61. The seed detection unit 207 converts the output of the gloss sensor 16 into information indicating the gloss and sends it to the gloss condition comparison unit 206 to determine whether the gloss mode can be executed. Determine whether to use.
[0073]
[Paper Type Detection]
FIG. 9 is a diagram illustrating the arrangement of the gloss sensor 16.
[0074]
The gloss sensor 16 and the paper type detection unit 207 measure the gloss by a method specified in JIS Z8741. That is, a light beam having a specified incident angle and a specified opening angle is incident on the recording paper accommodated in the sheet cassette 61, and the light beam having the specified opening angle reflected in the mirror reflection direction is measured by a light receiver. is there.
[0075]
In FIG. 8, a light beam emitted from the light source 108 passes through the lens 110 and is incident on the recording paper P at an angle θ. The light beam reflected in the mirror reflection direction passes through the lens 110 and enters the light receiver 109. Then, the paper type detection unit 207 obtains the gloss level of the recording paper P from the output signal of the light receiver 109. By arranging such a gloss sensor 16 in each paper feed cassette 61, the gloss of the recording paper surface can be detected. In the present embodiment, the glossiness is detected with the incident angle θ being 60 degrees.
[0076]
As shown in FIG. 9, the gloss sensor 16 is installed so as to measure the surface of the uppermost recording sheet accommodated in the sheet cassette 61, and is capable of following the recording sheet even if the accommodation amount of the recording sheet changes. Make it work. Further, a glass plate (calibration (CAL) plate 17) having a refractive index of 1.567 is adhered to the bottom surface of the paper feed cassette 61 to calibrate the gloss sensor 61, and the glass surface is irradiated with a light beam. Then, the amount of specular (regular) reflection from the glass surface is set as a reference value (gloss level 100). The calibration is performed when the recording paper stored in the paper cassette 61 runs out.
[0077]
[Print Control]
FIG. 10 is a flowchart illustrating print control by the CPU 210.
[0078]
When printing is instructed, the CPU 210 determines whether the description of the gloss information of the target profile is “glossy” or “matte” (S11). In the case of "matting", the image forming mode is set to the normal mode, the image processing unit is made to perform color conversion, and the converted image signal is sent to the printer unit 204 to form an image (S12).
[0079]
On the other hand, in the case of "glossy", it is determined whether or not glossy paper is stored in the paper feed cassette 61 (S13). If the output signal of the gloss sensor 16 indicates a gloss level of 30 or more, it is determined that glossy paper is stored in the sheet cassette 61. The boundary between glossy and matte is not clear, and the gloss varies depending on the incident angle of reflection of the gloss meter. The above-mentioned threshold value “30” is based on the result obtained by measuring the glossiness of a recording paper called a coated paper by the inventors using the glossiness sensor 16.
[0080]
When glossy paper is stored in the paper feed cassette 61, the image forming mode is set to the glossy mode, the image processing unit performs color conversion for the glossy mode, and the converted image signal is sent to the printer unit 204. The image is sent to form an image (S14).
[0081]
On the other hand, when glossy paper is not stored in the paper feed cassette 61, there is no glossy paper in the operation unit 300 (or the computer device), and a message to request supply of glossy paper and "continue / continue after paper feed / A message asking "stop" is displayed (transmitted) (S15), and a response from the user is waited for (S16).
[0082]
When the user selects “continue after sheet feeding” (S16), and CPU 210 detects that the sheet cassette 61 has been inserted or removed (S17), the CPU 210 determines that the recording sheet has been fed, and returns the process to step S13.
[0083]
When the user selects “continue” (S16), the CPU 210 selects the paper cassette in which the recording paper with the highest gloss is stored (S18), and performs color conversion for the gloss mode in the image processing unit. Then, the converted image signal is sent to the printer unit 204, and an image is formed under the fixing condition in which the glossiness is improved more than usual (S19).
[0084]
When the user selects “stop” (S16), the image formation is stopped (S20).
[0085]
[Fixing control]
The fixing control is based on the paper weight specified from the operation unit 300 or the like. FIG. 11 is a diagram illustrating an example of the fixing speed according to the paper weight.
[0086]
FIG. 12 is a diagram showing the fixing control for each mode.
[0087]
[Select glossy mode]
In addition to the selection of the gloss mode by the user, the gloss mode may be selected under the following conditions.
-"Glossy" is described in the target profile
・ There is no matte paper
[0088]
The condition "" glossy "is described in the target profile" refers to the attribute tag of the target profile to determine whether to form an image in the glossy mode. In other words, if “glossy” is described in the attribute tag of the target profile, the glossy mode is set (fixing conditions for image output, paper type, destination ICC profile for glossy mode selection), and an image is formed. I do.
[0089]
The condition “the matte paper does not exist” means that when an image is formed on glossy paper under normal fixing conditions in a non-standard state where no high-quality paper (matte paper) is present, the degree of melting of the toner is low, There is a glossiness at the base of the image, and the place where the toner is applied has a low glossiness, which results in an output image having a strange feeling. Such images are particularly disliked by portrait images, and have high glossiness in areas where the image ratio such as skin color is low, and low glossiness in areas where the image ratio such as hair and clothes is high, that is, photos and images. The result is a low-quality image that is far from printed matter. In order not to output such a low-quality image, an image is formed in a glossy mode when there is only glossy paper.
[0090]
As described above, in the present embodiment, a profile for color conversion can be downloaded, and it is determined whether or not the downloaded profile is for the glossy mode, and registration (storage) of the downloaded profile is controlled in accordance with the determination. I do. Further, when an image formation in the gloss mode is instructed, it is determined whether or not there is glossy paper, and the image formation is controlled according to the determination.
[0091]
Further, in the gloss mode, the gloss mode is set so as to be a gloss condition close to the target output environment with reference to the gloss condition of the target profile, and gloss matching is possible.
[0092]
Further, it is possible to execute the image formation in the gloss mode under the conditions such as “glossy” is described in the target profile, matte paper does not exist, and the like.
[0093]
[Second embodiment]
Hereinafter, the image processing according to the second embodiment of the present invention will be described. Note that, in the present embodiment, the same reference numerals are given to configurations substantially similar to those of the first embodiment, and detailed description thereof will be omitted.
[0094]
In the second embodiment, an example will be described in which information for realizing more accurate gloss matching is incorporated into an image forming apparatus in a private tag of an ICC profile.
[0095]
The ICC profile may include a public tag required by a general CMM for color matching, an optional public tag used for performing additional conversion, and a private tag used in a custom CMM. Gloss information can be included in this private tag. That is, since glossiness information is described in addition to glossiness / matte, which is glossiness information of the attribute tag, glossiness information obtained by the paper type detection unit 207 and glossiness information included in the private tag are described. This can be used to prepare an environment that provides a more faithful output image with a glossiness desired by the user.
[0096]
The following is the gloss information included in the private tag.
ave_G tag: average glossiness of C, M, Y, Bk, R, G, B and 3K
Sig_G table tag: Signal sum (0 to 300%) vs. gloss (0 to 100)
white_G tag: media gloss (gloss of a patch where each image signal is 0%)
Here, the signal sum is the sum of the respective color component signals.
[0097]
By changing the configuration that refers to the attribute tag in the first embodiment to a configuration that refers to the white_G tag in the private tag, gross matching with higher precision can be performed. Furthermore, by registering (storing) the target profile and the destination profile for each gloss level of the recording paper, the gloss level of the recording paper can be selected with high accuracy, and more faithful gloss matching can be performed. .
[0098]
[Gloss matching]
FIG. 13 is a flowchart illustrating gross matching, which is a process executed by the CPU 210. The description will be made on the assumption that typical CMYK data is input.
[0099]
The gloss information (White_G tag) of the recording paper used when the profile was created is read from the private tag of the profile to be the target designated by the user (S31), and is stored in the paper cassette 61. The gloss information of the recording paper is detected (S32). Then, a gloss difference ΔG is calculated based on the gloss information described in the profile and the detected gloss information of the recording paper (S33), and the recording paper cassette 61 containing the recording paper with the minimum ΔG is stored. Select (S34). Then, the color conversion is performed with reference to the destination profile corresponding to the recording paper (S35), and thereafter, the fixing control is performed based on the fixing condition of the selected recording paper, and an output image having glossiness desired by the user is obtained. (S35).
[0100]
Note that it is desirable to understand the mechanism of the color copying machine of the present embodiment and store a plurality of types of recording paper in the paper feeding unit. If the difference ΔG in gloss from the target is 20 or more, an error message is displayed, and as in the first embodiment, another recording sheet is supplied, image formation is continued, The user may select whether to stop the formation.
[0101]
[Modification]
For a user who needs only a moderate glossiness, the glossiness sensor 16 installed corresponding to each paper feed cassette 61 only increases the cost of the apparatus. Therefore, if the paper type detection unit 207 and the gloss sensor 16 in the first embodiment are deleted and the user selects “glossy paper” or “plain paper” when inputting the paper weight, the cost is reduced. Can be reduced.
[0102]
[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.
[0103]
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.
[0104]
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.
[0105]
When the present invention is applied to the storage medium, the storage medium stores program codes corresponding to the flowcharts described above.
[0106]
【The invention's effect】
As described above, according to the present invention, image formation can be controlled according to gloss information described in a profile.
[0107]
Further, image formation can be controlled according to gloss information described in the profile and the type of recording paper usable for image formation.
[0108]
Also, a profile with an accurate description can be stored.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining color conversion using an ICC profile;
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 diagram showing a schematic configuration of a color copying machine;
FIG. 5 is a block diagram illustrating a configuration example of a color conversion unit (part of an image processing unit) in the color copying machine;
FIG. 6 is a flowchart showing an ICC profile determination process;
FIG. 7 is a view for explaining a change in glossiness with respect to density.
FIG. 8 is a diagram illustrating a configuration example of a gloss sensor.
FIG. 9 is a diagram illustrating an arrangement of a gloss sensor 16;
FIG. 10 is a flowchart illustrating printing in a gloss mode.
FIG. 11 is a diagram illustrating an example of a fixing speed according to a paper weight;
FIG. 12 is a diagram showing fixing control for each mode.
FIG. 13 is a flowchart illustrating gross matching.

Claims (18)

An image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space,
Acquisition means for acquiring gloss information described in the profile;
An image processing apparatus comprising: a control unit that controls image formation based on a comparison result between the gloss information and a set image forming mode. An image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space,
Acquisition means for acquiring gloss information described in the profile;
Detecting means for detecting the type of recording medium that can be used for image formation;
An image processing apparatus comprising: a control unit that determines a recording medium and an image forming mode to be used for image formation based on the gloss information and the type of the recording medium, and controls image formation. The image processing apparatus according to claim 2, wherein the control unit sets a gloss mode as the image forming mode when the gloss information indicates gloss and the type of the recording medium indicates gloss paper. apparatus. When the gloss information indicates glossy and the type of the recording medium indicates non-glossy paper, the control unit selects a recording medium having the highest glossiness and performs image formation under a fixing condition in which the glossiness is improved. The image processing apparatus according to claim 2, wherein: An image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space,
Glossiness information of a target described in a profile related to color conversion from the device-specific color space to the device-independent color space, as well as the device-independent color space to the device-specific color space Acquiring means for acquiring destination glossiness information described in a profile related to color conversion;
An image processing apparatus comprising: a control unit that determines a recording medium to be used for image formation and an image formation mode based on a comparison result of the gloss information of the target and the destination, and controls image formation. An image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space,
Acquisition means for acquiring target glossiness information described in a profile related to color conversion from a color space unique to the device to a color space independent of the device,
Detecting means for detecting the glossiness of a recording medium usable for image formation;
A control unit that determines a recording medium to be used for image formation, an image formation mode and a destination profile based on the glossiness information of the target and a comparison result of the glossiness of the recording medium, and controls image formation. Characteristic image processing device. The image processing apparatus according to claim 5, wherein the gloss information is described in a private tag. An image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space,
A memory in which the profile is stored;
An image processing apparatus comprising: a control unit configured to determine a description of a gloss condition of a profile to be stored in the memory and control storage of the profile based on the determination result. When the storage of the gloss mode profile is instructed, the control unit stores the profile in the memory when the description of the gloss condition indicates glossy, and when the description of the gloss condition indicates matte, The image processing apparatus according to claim 8, wherein the profile is discarded. When the storage of the profile for the gloss mode is instructed, and when the gloss condition is not described, a message asking whether or not the profile is created using glossy paper is displayed. The image processing apparatus according to claim 8, wherein: When a response indicating that the profile is a profile created using the glossy paper is obtained, the control unit adds a description indicating glossiness to the profile as the gloss condition and stores the profile in the memory. The image processing apparatus according to claim 10, wherein: A method for controlling an image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space,
Obtain gloss information described in the profile,
A control method, wherein image formation is controlled based on a comparison result between the gloss information and a set image forming mode. A method for controlling an image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space,
Obtain gloss information described in the profile,
Detects the type of recording medium that can be used for image formation,
A control method comprising: determining a recording medium and an image forming mode to be used for image formation based on the gloss information and the type of the recording medium, and controlling image formation. A method for controlling an image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space,
Glossiness information of a target described in a profile related to color conversion from the device-specific color space to the device-independent color space, as well as the device-independent color space to the device-specific color space Get the destination glossiness information described in the profile for color conversion,
A control method comprising: determining a recording medium to be used for image formation and an image formation mode based on a comparison result of the gloss information of the target and the destination, and controlling the image formation. A method for controlling an image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space,
Obtaining the target glossiness information described in the profile related to color conversion from the device-specific color space to the device-independent color space,
Detects the glossiness of a recording medium that can be used for image formation,
A control method comprising: determining a recording medium to be used for image formation, an image formation mode, and a destination profile based on gloss information of the target and a comparison result of the glossiness of the recording medium, and controlling image formation. . A method for controlling an image processing apparatus that performs color conversion based on a profile describing information on color conversion between a device-specific color space and a device-independent color space,
Determine the description of the gloss condition of the profile to be stored in the memory where the profile is stored,
A control method characterized by controlling storage of a profile based on a result of the determination. A program for controlling an image processing apparatus to execute the control according to any one of claims 12 to 16. A recording medium on which the program according to claim 17 is recorded.

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