JP2007166544A - Image processing device and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processing device and method therefor capable of obtaining images which can be viewed always in a fixed manner, even if the type of output device and output conditions are different. <P>SOLUTION: An image processing method sets and stores the setting information including a type of a device by which a user outputs an image and an output condition in the device (S1), determines color conversion parameters based on the stored setting information (S2), executes color conversion processing for performing a color conversion of input image data by using the color conversion parameter determined (S3 and S4), and outputs the color-converted image data to a printer (S5). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image processing apparatus and method for performing color conversion processing on color image data and outputting the result.

  In recent years, in addition to the spread of personal computers and color printers, which are peripheral devices, devices such as digital cameras, digital videos, and scanners have become widespread. Along with this, the printing of digital images by printers has attracted attention. Color reproduction by such a printer generally depends on characteristics initially set by the printer manufacturer.

  For this reason, it is extremely difficult to perform printing with color reproduction ideal for the user. This is due to diversification of printer types such as inkjet printers and electrophotographic printers, diversification of media types such as plain paper and glossy paper, and differences in observation environments in different light sources such as office environments and home living rooms. . That is, due to these diversification and differences in observation environment, even if printing is performed under the same conditions, the color reproduction of the printed image will be different.

For this reason, in order to obtain an ideal color reproduction, the user himself / herself needs to perform image correction. Here, as a typical means for the user to adjust the color reproduction,
(1) A method for generating an ICC profile (2) A method for printing after correcting an image with an image application (3) A method using an image correcting means prepared in a driver, etc. can be considered.

  Here, when the method of generating the ICC profile is used, the color reproduction can be adjusted with the highest color reproduction accuracy and with a high degree of freedom. However, this adjustment requires advanced knowledge about color reproduction, and it is necessary to provide expensive equipment for general consumers such as spectroscopic measurement or dedicated software. Therefore, consumers who have mastered such a technique generally perform gradation correction, contrast correction, brightness correction, etc. using an image application to make adjustments to achieve ideal color reproduction.

  However, in such a method, the user needs to check the print image in the observation environment every time the type of printer, the type of media, and the observation environment are different, and repeat the adjustment until an ideal color reproduction is obtained. For this reason, much time and cost are required to obtain an ideal image. In addition, knowledge regarding image correction is required for such adjustment, and a cost for purchasing an application that performs image correction is generated. Therefore, problem solving by this method is not practical for consumers who make the majority. Therefore, the most practical method for providing image correction to such a consumer is to provide a simple means for obtaining ideal color reproduction from a printer driver.

  As an example of image correction in a printer driver, there are provided a method for automatically adjusting color reproduction in a batch and a correction means for performing density correction for each color material such as ink. However, even if such a means is used, it is necessary to repeat the process of visually confirming the printed image and performing color adjustment according to the observation result. For this reason, a lot of time and printing costs are required until an image that is “visible” ideal for the user is obtained under an observation environment with different types of printers, media types, and light sources.

  An object of the present invention is to solve such conventional problems.

  A feature of the present invention is to provide an image processing apparatus and method that can always obtain an image that looks constant regardless of the type of output device and output conditions.

In order to achieve the above object, an image processing apparatus according to an aspect of the present invention has the following arrangement. That is,
A setting means for allowing the user to set the setting information including the type of the device that outputs the image and the output condition in the device;
Storage means for storing setting information set by the setting means;
Parameter determining means for determining a color conversion parameter based on setting information stored in the storage means;
Color conversion processing means for performing color conversion of input image data using the color conversion parameters determined by the parameter determination means;
Output means for outputting the image data color-converted by the color conversion means to the device;
It is characterized by having.

In order to achieve the above object, an image processing method according to an aspect of the present invention includes the following steps. That is,
A setting step for allowing the user to set the setting information including the type of the device that outputs the image and the output condition in the device;
A storing step for storing the setting information set in the setting step;
A parameter determining step for determining a color conversion parameter based on the setting information stored in the storing step;
Using the color conversion parameter determined in the parameter determination step, a color conversion processing step for performing color conversion of input image data;
An output step of outputting the image data color-converted in the color conversion step to the device;
It is characterized by having.

  According to the present invention, there is an effect that an image that always looks constant can be obtained even if the type of output device and the output condition are different.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments do not limit the present invention according to the claims, and all combinations of features described in the present embodiments are essential to the solution means of the present invention. Not exclusively.

  FIG. 1 is a block diagram illustrating a functional configuration of a printer driver according to Embodiment 1 of the present invention.

  In the figure, reference numeral 101 denotes a printer driver according to the present embodiment. The printer driver 101 includes a color conversion processing unit 102, a parameter storage unit 103, a user setting information storage unit 104, and a user setting unit 110. The user setting unit 110 includes a printer selection unit 105, a media selection unit 106, and an observation environment selection unit 107. Reference numeral 108 denotes input image data, and 109 denotes output image data. Each unit in FIG. 1 is realized by a program module.

  FIG. 2 is a block diagram illustrating a hardware configuration of a personal computer (information processing apparatus) in which the printer driver 101 according to the present embodiment is installed.

  In the figure, a CPU 201 controls the operation of the entire information processing apparatus in accordance with programs stored in a RAM 202 and a ROM 203. The RAM 202 is used as a main memory of the CPU 201, and a program to be executed by the CPU 201 is loaded. The RAM 202 provides a work area for temporarily storing various data during the control operation by the CPU 201. The ROM 203 stores a boot program and various data in a nonvolatile manner. The input unit 205 has a pointing device such as a keyboard and a mouse, and is used to input various data and commands by a user operation. The display unit 204 includes a display unit such as a CRT or a liquid crystal, and is used to display data to be processed, a UI screen described later, and the like. An external storage device (HD) 206 is a large-capacity storage device, in which an OS, various application programs, a printer driver, data, and the like are preinstalled. When the activation of the program is instructed, the program is loaded into the RAM 202 and executed. The network interface 207 controls an interface with the network 210 such as a LAN. A plurality of printers 211 and various input / output devices are connected to the network 210.

  FIG. 3 is a flowchart for explaining color conversion processing by the printer driver 101 according to this embodiment. A program for executing this processing is installed in the HD 206 in advance, and is loaded into the RAM 202 and executed under the control of the CPU 201 at the time of execution.

  First, in step S1, an application for displaying the UI screen shown in FIG. 4 associated with the printer driver 101 is activated.

  FIG. 4 is a diagram illustrating an example of a UI screen for performing various settings by the user in the printer driver 101 according to the present embodiment. Such a UI screen and a configuration for performing various settings based on the UI screen correspond to setting means.

  This UI screen is displayed on the display unit 204. In the figure, 301 is a selection button for selecting a printer to be used for printing, 302 is a selection button for selecting the type (output condition) of a medium (recording sheet) used in the printer, and 303 is its button. This is a selection button for selecting an observation environment for observing a printed recording sheet. Reference numeral 304 denotes a button for reading setting information set in advance, and reference numeral 305 denotes a button for registering the contents set by the buttons 301 to 303. Note that the setting information is not limited to the example of FIG. 4 and may include at least one of them, or other items may be added.

  Accordingly, in step S1, a printer for printing an image, a type of recording sheet used for printing by the printer, and an observation environment for the printed image are selected in 301 to 303, respectively. The user setting information selected in this way is stored in the format shown in FIG. It should be noted that selection of items for each button is performed using the keyboard of the input unit 205 or a pointing device (mouse).

  FIG. 5 is a diagram illustrating an example of setting information by the user set in step S <b> 1 and stored in the user setting information storage unit 104.

  The set information is temporarily stored in the RAM 202, and when the “registration” button 305 is instructed, the information is registered in the HD 206 together with the printer driver 101 in a nonvolatile manner.

  In the example of FIG. 5, “printer A” is selected as the printer, the recording sheet to be used is set to “mat paper”, and the observation environment is set to “home living”.

  In step S 2, the color conversion parameter associated with the user setting information selected in step S 1 is automatically selected from the parameter storage unit 103. This detailed selection method will be described later in detail.

  FIG. 6 is a diagram conceptually illustrating a state in which the parameter storage unit 103 according to the present embodiment stores color conversion parameters corresponding to printing sheets and observation environments for each printer model.

  For example, when “printer A” is selected and “plain paper” is selected as the output paper, “parameter 111” is selected. Furthermore, when an observation environment is set for this, another parameter is set according to the observation environment.

  In step S 3, the color conversion parameter information selected in step S 2 is sent to the color conversion processing unit 102. In step S4, color conversion processing is performed on the input image data using the color conversion parameters received from the parameter storage unit 103 in step S3. This color conversion processing method will be described later. In step S5, the output image data color-converted in step S4 is transmitted to the selected printer for printing.

  Next, a method of selecting the color conversion parameter associated with the user setting information from the parameter storage unit 103 in step S2 will be described.

  Information such as the printer type, media type, and observation environment set in step S1 in FIG. 3 is stored in the user setting information storage unit 104 in the format shown in FIG. 5 as described above.

  FIG. 7 is a flowchart for describing processing for selecting a color conversion parameter corresponding to each setting information. Here, it is assumed that the color conversion parameter is uniquely determined based on the three variables i, j, and k. A program for executing this process is loaded into the RAM 202 at the time of execution and executed under the control of the CPU 201.

  In steps S11 to S13, it is determined which of the printers A to C is the selected printer. In each of steps S14 to S16, each printer is selected according to the selected printer model. Corresponding to, the value of the variable i is set to any one of 1-3. Here, for example, i = 1 is set for the printer A, i = 2 is set for the printer B, and i = 3 is set for the printer C. Step S17 shows a case other than printers A to C. In this case, i = 4 is set.

  Next, in steps S18 to S21, the type of recording sheet to be used by the selected printer is determined. In each of steps S22 to S25, the value of the variable j is set to 1 according to the selected type of recording sheet. Set to any of ~ 4. Here, for example, j = 1 for “plain paper”, j = 2 for “glossy paper”, j = 3 for “matte paper”, and “art paper”. Are set to j = 4, respectively. Step S26 shows a case where the type of the recording sheet is other than “plain paper”, “glossy paper”, “matte paper”, and “art paper”, and in this case, j = 5 is set.

  Further, in steps S27 to S29, it is determined whether the environment for observing the image printed by the printer is “office”, “presentation room”, or “meeting room A”. In each of steps S30 to S32, The value of the variable k is set to any one of 1 to 3 according to the selected observation environment. Here, for example, k = 1 is set for the “office”, k = 2 is set for the “presentation room”, and k = 3 is set for the “conference room”. Step S33 indicates a case other than “Office”, “Presentation Room”, and “Conference Room A”. In this case, k = 4 is set. These variables i, j, and k are stored in the work area of the RAM 202, respectively.

  The parameters [i] [j] [k] are uniquely determined in step S34 based on the variables i, j, and k thus determined.

  In this way, parameters can be acquired from the parameter storage unit 103 (FIG. 6) based on the parameters [i] [j] [k] corresponding to the printer type, media type (recording sheet type), and observation environment.

  In this example, the parameters determined by the third order of the variables i, j, and k are shown as examples. However, the parameters determined by the multi-order variables are set according to the combination of the printer type, the media type, the observation environment, and other parameters. It may be stored.

  Next, the color conversion process in step S4 of FIG. 3 will be described.

  The parameter storage unit 103 schematically shown in FIG. 6 stores color conversion parameters for output to the printer with ideal color reproduction associated with the type of printer, media type, and observation environment selected by the user. Has been. It is assumed that the color conversion parameters are stored for a number corresponding to combinations of user setting information. Therefore, the parameter storage unit 103 according to the present embodiment stores 4 × 5 × 4 = 80 types of color conversion parameters of four types of printers, five types of media, and four types of observation environments. In this example, the settings are 4 types, 5 types, 4 types, etc., but even if additional setting items are added, the same processing is possible if color conversion parameters are stored for the combination. become. These color conversion parameters are very high-precision color conversion parameters. This is because an image printed by a printer is known to have different colors depending on the type of printer, the type of media, and the environment (light source) to be observed. For this reason, in order to print with an ideal color reproduction, a very strict color matching technique is required.

  FIGS. 8A and 8B are diagrams for explaining the difference in the observation environment between the office and the living room.

  FIG. 8A shows a case where the observation environment is an office, and is generally proved by light close to white light such as a fluorescent lamp. On the other hand, FIG. 8B shows a case where the observation environment is a living room at home, and in this environment, an incandescent light bulb or the like is used, and illumination is performed with relatively warm color light.

  FIG. 9 is a diagram for explaining the color conversion parameters according to the present embodiment, and is described by the correspondence between the color coordinate data of the grid points in the RGB color space and the coordinate values of the CMYK color space reproduced by these grid points. ing.

  At the top of this data structure, each step value of the RGB value is described, and thereafter, the color coordinate C, M, Y, K value corresponding to each grid point is nested in the order of R, G, B. is described. According to this, for example, the CMYK values of Grid RGB = 0, 0, 0 are (250, 200, 230, 100), and so on. CMYK values for each grid up to (0, 0, 0, 0) are set.

  This example shows a case where the RGB values are each 8 bits, and since the step of each value of RGB is “32”, the maximum RGB value of the grid is “8”.

  FIG. 10 is a diagram schematically showing the data structure of the color conversion parameter according to the present embodiment in the RGB color space.

  This color conversion parameter is selected from the parameter storage unit 103 based on information stored in the user setting information storage unit 104 (FIG. 5). The color conversion parameter thus selected is transferred to the color conversion processing unit 102.

  FIG. 11 is a diagram for explaining color conversion processing by the color conversion processing unit 102 according to the present embodiment.

  The color conversion parameters transferred from the parameter storage unit 103 are stored in the parameter storage unit 1103.

  The input image data 108 is passed to the color conversion processing unit 102. If the input image data is RGB data, the color conversion processing unit 102 converts the passed RGB image data into output image data 109 using color conversion parameters. Here, the output image data is CMYK data.

  A specific conversion method will be described.

  Four neighboring RGB values surrounding each pixel value (Ri, Gi, Bi) of the input RGB image data are searched from the RGB grid points described in the color conversion parameters. The four points of RGB data searched in this way are set as (R1, G1, B1), (R2, G2, B2), (R3, G3, B3), (R4, G4, B4). Each RGB data has CMYK values (C1, M1, Y1, K1), (C2, M2, Y2, K2), (C3, M3, Y3, K3), (C4, M4, Y4, K4). Tetrahedral interpolation is performed from the CMYK value information for these RGB values, and CMYK values corresponding to the respective RGB pixel values are calculated. In this way, CMYK values corresponding to the RGB values of all pixels of the input image data are calculated and stored as output image data 904. Then, the stored output image data 904 is transmitted to the printer, thereby printing the image.

  As described above, according to the first embodiment, it is possible to perform printing with ideal color reproduction according to the type of printer, the type of media, and the image observation environment. Therefore, the user can obtain an ideal print image that always looks constant even when the output conditions and viewing conditions of the printer are different.

<Embodiment 2>
Next, an image processing apparatus according to Embodiment 2 of the present invention will be described.

  In the second embodiment, a plurality of user setting information can be stored in the user setting information storage unit 104.

  FIG. 12 is a diagram showing an example of a plurality of setting information stored in the user setting information storage unit 104 according to Embodiment 2 of the present invention.

  Here, three types of setting information “setting 1” to “setting 3” are stored.

  For this setting, it is possible to register a plurality of user setting information selected in step S1 of FIG. 3 by instructing the “registration button” 305 of the application of FIG.

  When a “registration button” 305 is designated in FIG. 4, a window (not shown) for specifying the setting name is displayed. In this window, by inputting a setting name such as “Setting 1” or “Setting 2” as in the example of FIG. 12, setting information corresponding to the name is registered. This setting name may be a user name, for example.

  Alternatively, the registration number (setting information number) may be updated emotionally each time registration is performed.

  The setting information set and stored in this way can be recalled as necessary during printing.

  FIG. 13 is a diagram showing a display example of setting information when the “select from preset” button 304 is instructed on the UI screen of FIG. 4 in the second embodiment.

  In FIG. 13, “Setting 1” to “Setting 3” are displayed corresponding to the setting information of FIG. Here, when the user selects desired setting information from the displayed plurality of setting information, (printer type, media type, observation environment) can be set according to the setting information. Here, the case has been described in which three types of parameters of the printer type, the media type, and the observation environment are set, but a plurality of setting information can be similarly stored even if there are three or more types.

  FIG. 14 is a flowchart for explaining setting information reading processing according to the second embodiment.

  In this process, after the “select from preset” button 304 is instructed on the UI screen of FIG. 4 and a plurality of setting information as shown in FIG. 13 is displayed, one of the setting information is selected and set. It is executed when reading of information is instructed.

  First, in step S41, it is determined whether or not “Setting 1” has been selected and instructed. If “Setting 1” is selected, the process proceeds to step S42, and the printer model, media type, and observation environment registered as “Setting 1” are set. If it is not “Setting 1” in Step S41, the process proceeds to Step S43 to check whether “Setting 2” is selected and instructed. If “Setting 2” is selected, the process proceeds to step S44, and the printer model, media type, and observation environment registered as “Setting 2” are set. If it is not “setting 2” in step S43, the process proceeds to step S45, and the printer model, media type, and observation environment registered as “setting 3” in FIG. 12 are set.

  Here, the case where there are three types of setting information is shown, but more setting information may be stored.

  Processing from selecting a color conversion parameter from a plurality of user setting information stored in this way, through color conversion processing, and printing with a printer is the same as in the method of the first embodiment.

(Other embodiments)
The embodiment of the present invention has been described in detail above. However, the present invention may be applied to a document search system including a plurality of devices or a document search apparatus including a single device. good.

  In the present invention, a software program that implements the functions of the above-described embodiments is supplied directly or remotely to a system or apparatus, and the computer of the system or apparatus reads and executes the supplied program. Can also be achieved. In that case, as long as it has the function of a program, the form does not need to be a program.

  Accordingly, since the functions of the present invention are implemented by computer, the program code installed in the computer also implements the present invention. That is, the claims of the present invention include the computer program itself for realizing the functional processing of the present invention. In this case, the program may be in any form as long as it has a program function, such as an object code, a program executed by an interpreter, or script data supplied to the OS.

  Various recording media for supplying the program can be used. For example, floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, MO, CD-ROM, CD-R, CD-RW, magnetic tape, nonvolatile memory card, ROM, DVD (DVD-ROM, DVD- R).

  As another program supply method, the program can be supplied by connecting to a home page on the Internet using a browser of a client computer and downloading the program from the home page to a recording medium such as a hard disk. In this case, the computer program itself of the present invention or a compressed file including an automatic installation function may be downloaded. It can also be realized by dividing the program code constituting the program of the present invention into a plurality of files and downloading each file from a different homepage. That is, a WWW server that allows a plurality of users to download a program file for realizing the functional processing of the present invention on a computer is also included in the claims of the present invention.

  Further, the program of the present invention may be encrypted, stored in a storage medium such as a CD-ROM, and distributed to users. In that case, a user who has cleared a predetermined condition is allowed to download key information to be decrypted from a homepage via the Internet, and using the key information, the encrypted program can be executed on a computer in a format that can be executed. To be installed.

  Further, the present invention can be realized in a form other than the form in which the functions of the above-described embodiments are realized by the computer executing the read program. For example, based on the instructions of the program, an OS or the like running on the computer performs part or all of the actual processing, and the functions of the above-described embodiments can also be realized by the processing.

  Furthermore, the program read from the recording medium may be written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer. In this case, thereafter, based on the instructions of the program, the CPU or the like provided in the function expansion board or function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing. .

  As described above, according to the present embodiment, color conversion parameters that can be output to a printer with a certain ideal color reproduction are automatically set according to the type of printer, the type of media, and the image observation environment. Can be selected. Therefore, the user does not need complicated color adjustment and visual confirmation that require a lot of time and printing costs, and it is ideal that it always looks constant even if the output conditions and viewing conditions of the printer are different. Digitized images can be printed with accurate color reproduction.

2 is a block diagram illustrating a functional configuration of a printer driver according to Embodiment 1 of the present invention. FIG. It is a block diagram explaining the hardware constitutions of the personal computer (information processing apparatus) which mounts the printer driver which concerns on this Embodiment. 6 is a flowchart illustrating color conversion processing by the printer driver according to the present embodiment. FIG. 5 is a diagram illustrating an example of a UI screen for performing various settings by a user in the printer driver according to the present embodiment. It is a figure which shows an example of the setting information by the user set by step S1 of FIG. 3, and memorize | stored in the user setting information storage part. FIG. 5 is a diagram conceptually illustrating a state in which color conversion parameters corresponding to output sheets and observation environments for each printer model are stored in a parameter storage unit according to the present embodiment. It is a flowchart explaining the process which selects a color conversion parameter corresponding to each setting information. It is a figure explaining the difference in the observation environment in each of an office and a living room. It is a figure explaining the color conversion parameter which concerns on this Embodiment. It is the figure which represented typically the data structure of the color conversion parameter which concerns on this Embodiment in RGB color space. It is a figure explaining the color conversion process by the color conversion process part which concerns on this Embodiment. It is a figure which shows an example of the some setting information memorize | stored in the user setting information storage part which concerns on Embodiment 2 of this invention. FIG. 5 is a diagram illustrating a display example of setting information when a “select from preset” button 304 is instructed on the UI screen of FIG. 4 in the second embodiment. 10 is a flowchart for explaining setting information reading processing according to the second embodiment;

Claims (10)

A setting means for allowing the user to set the setting information including the type of the device that outputs the image and the output condition in the device;
Storage means for storing setting information set by the setting means;
Parameter determining means for determining a color conversion parameter based on setting information stored in the storage means;
Color conversion processing means for performing color conversion of input image data using the color conversion parameters determined by the parameter determination means;
Output means for outputting the image data color-converted by the color conversion means to the device;
An image processing apparatus comprising:   2. The apparatus according to claim 1, wherein the device is a printer, and the setting unit sets a type of the printer, a type of a recording medium used by the printer, and an observation environment of an image printed by the printer. Image processing device. The parameter determination means includes
Parameter storage means for storing color conversion parameters corresponding to each possible value of the setting information;
The image processing apparatus according to claim 1, wherein a color conversion parameter is determined by referring to the parameter storage unit based on setting information stored in the storage unit.   The image processing apparatus according to claim 1, wherein the color conversion parameter is a parameter for converting RGB values into CMYK values.   The color conversion processing unit obtains RGB values of four neighboring points surrounding each pixel value of the input RGB image data based on the color conversion parameter, and the RGB values of the four neighboring points specified by the color conversion parameter 5. The image processing apparatus according to claim 4, wherein the CMYK value corresponding to the image data is obtained, and the CMYK value of the input image data is obtained by tetrahedral interpolation of the CMYK value. A setting step for allowing the user to set the setting information including the type of the device that outputs the image and the output condition in the device;
A storing step for storing the setting information set in the setting step;
A parameter determining step for determining a color conversion parameter based on the setting information stored in the storing step;
Using the color conversion parameter determined in the parameter determination step, a color conversion processing step for performing color conversion of input image data;
An output step of outputting the image data color-converted in the color conversion step to the device;
An image processing method comprising:   7. The apparatus according to claim 6, wherein the device is a printer, and in the setting step, a type of the printer, a type of a recording medium used by the printer, and an observation environment of an image printed by the printer are set. Image processing method. The parameter determination step includes
A color conversion parameter is stored corresponding to each possible value of the setting information, and the color conversion parameter is determined with reference to the stored color conversion parameter based on the stored setting information. The image processing method according to claim 6, wherein:   The image processing method according to claim 6, wherein the color conversion parameter is a parameter for converting RGB values into CMYK values.   The color conversion processing step acquires RGB values of four neighboring points surrounding each pixel value of the input RGB image data based on the color conversion parameters, and the RGB values of the four neighboring points specified by the color conversion parameters 10. The image processing method according to claim 9, wherein a CMYK value corresponding to the image data is obtained, and a CMYK value of the input image data is obtained by tetrahedral interpolation of the CMYK value.

Images