The present invention relates to a technology for adjusting a profile used to convert coordinate values of a color space.
When an ink jet printer is used to calibrate printing such as offset printing, color reproduction precision to be requested (the degree of accurately color reproduction) is very high. As a mechanism for realizing the color reproduction precision, there is a color management system that uses an international color consortium (ICC) profile. The ICC profile is data indicating a correspondent relation between device-independent color and a device-dependent color of a color device such as a printer (for example, an offset printer) or an ink jet printer. The device-dependent color of a printer or an ink jet printer is expressed by, for example, CMYK values indicating use amounts of cyan (C), magenta (M), yellow (Y), and black (K). The device-dependent color is expressed by, for example, saturation values of a CIE (international commission on illumination) L*a*b* color space (“*” is omitted and Lab values are used) or saturation values of a CIE XYZ color space which is a device-independent color space.
Here, an ICC profile of a printer is referred to as an input profile and an ICC profile of an ink jet printer is referred to as an output profile. When CMYK values (referred to as CMYKt values) in a printer are converted into saturation values (for example, Lab values) of a profile connection space (PCS) according to an input profile, the saturation values can be converted into CMYK values (referred to as CMYKp values) of the ink jet printer according to an output profile. When printing is executed by an ink jet printer according to the CMYKp values, colors closes to colors of a printer can be reproduced with the ink jet printer. Actually, expected colors may not be reproduced due to an error of a profile, a color measurement error, a variation in a printer, or the like in some cases. In these cases, conversion precision of target colors is improved by correcting the ICC profile.
JP-A-2003-87589 discloses a method of adjusting input values (Lab values) of an output profile for a CMYK printer to adjust color reproduction of the CMYK printer using a calibrator as a target device. Output values (CMYK values) of an output profile are invariable and an input profile is also invariable.
A user who uses the above-described color management system desires to set targets of CMYKt values in a printer or CMYKp values in an inkjet printer in some cases. In the profile adjustment method disclosed in JP-A-2003-87589, only targets of Lab values can be set and targets of CMYKt values or CMYKp values may not be set.
The above-described problem is not limited to an adjustment case of a profile targeting an inkjet printer and may also arise even when a profile targeting various color devices is adjusted.
An advantage of some aspects of the invention is that it is provides a technology capable of improving convenience of work for adjusting a profile to be used to convert coordinate values of a color space.
According to an aspect of the invention, there is provided a profile adjustment method of causing a computer to adjust a profile to be used to convert first coordinate values of a first color space into second coordinate values of a second color space. The profile adjustment method includes: accepting one of two or more kinds of profiles as an adjustment target profile among an input profile defining a correspondent relation between the first coordinate values and third coordinate values of a profile connection space, an output profile defining a correspondent relation between the third coordinate values and the second coordinate values, and a link profile defining a correspondent relation between the first coordinate values and the second coordinate values; accepting an adjustment target at coordinates at which an adjustment target color is expressed; and adjusting the adjustment target profile based on the accepted adjustment target.
According to another aspect of the invention, there is provided a profile adjustment method of causing a computer to adjusting a profile defining a correspondent relation between input coordinate values of an input color space and output coordinate values of an output color space. The profile adjustment method includes: accepting one of two or more kinds of color spaces as an adjustment target color space among the input color space, the output color space, and a profile connection space when the input color space and the output color space are not the profile connection space; accepting an adjustment target at coordinates at which an adjustment target color is expressed in the adjustment target color space; and adjusting the profile based on the accepted adjustment target.
According to still another aspect of the invention, there is provided a profile adjustment program causing a computer to realize functions corresponding to the steps of the above-described profile adjustment method.
According to still another aspect of the invention, there is provided a profile adjustment device including units corresponding to the steps of the above-described profile adjustment method.
According to still another aspect of the invention, there is provided a profile adjustment system including units corresponding to the steps of the above-described profile adjustment method.
In this case, it is possible to provide a technology for improving convenience of work for adjusting a profile to be used to convert coordinate values of a color space.
The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.
Hereinafter, embodiments will be described. Of course, the following embodiments are merely examples of the invention and all the characteristics described in the embodiments are not necessarily resolutions of the invention.
First, an overview of a technology included in the invention will be described with reference to examples illustrated in
According to an aspect of the technology, a profile adjustment method is a profile adjustment method of causing a computer that includes a central processing device (for example, a CPU 111) and a memory (for example, a ROM 112 and a RAM 113) to adjust a profile 500 to be used to convert first coordinate values (for example, CMYK values) of a first color space CS1 (for example, CMYK color spaces) into second coordinate values (for example, cmyk values) of a second color space CS2 (for example, a cmyk color space). The profile adjustment method includes an adjustment target profile designation step ST2, a target acceptance step ST4, and a profile adjustment step ST7. In the adjustment target profile designation step ST2, one of two or more kinds of profiles is accepted as an adjustment target profile 550 among an input profile 610 defining a correspondent relation between the first coordinate values and third coordinate values (for example, Lab values) of a profile connection space CS3 (for example, an Lab color space), an output profile 620 defining a correspondent relation between the third coordinate values and the second coordinate values, and a link profile (for example, a device link profile 630) defining a correspondent relation between the first coordinate values and the second coordinate values. In the target acceptance step ST4, an adjustment target T0 at coordinates at which an adjustment target color (for example, an adjustment point P0) is expressed is accepted. In the profile adjustment step ST7, the adjustment target profile 550 is adjusted based on the accepted adjustment target T0.
In the foregoing Aspect 1, a profile adjustment target can be designated from two or more kinds of profiles among the input profile 610, the output profile 620, and the link profile (630). Accordingly, this aspect can provide the profile adjustment method capable of improving convenience of work for adjusting the profile used to convert the coordinate values of the color space.
Here, the profile connection space includes color spaces such as a CIE Lab color space and a CIE XYZ color space.
The first color space includes the CMYK color space, the CMY color space, and the RGB color space. R stands for red, G stands for green, and B stands for blue.
The second color space includes the CMYK color space, the CMY color space, and the RGB color space. In the following embodiment, the second color space is notated as the cmyk color space to distinguish the second color space from the CMYK color space which is the first color space when the second color space is the CMYK color space.
The coordinates at which the adjustment target color may be expressed with the first coordinate values of the first color space, may be expressed with the second coordinate values of the second color space, or may be expressed with the third coordinate values of the profile connection space.
The adjustment target at the coordinates at which the adjustment target color is expressed may be expressed with the coordinate values of the color spaces or may be expressed with differences from the current coordinate values of the color space.
As exemplified in
For example, when color conversion is executed, it is preferable to combine the input profile and the output profile for use in color conversion. On the other hand, when color reproduction precision of a single profile is desired to be improved as in spot color matching or the like, it is preferable to use the single profile for color conversion. This aspect can provide a technology for further improving convenience of work for adjusting the profile used to convert the coordinate values of the color space since one of the combination of the profiles and the one profile is accepted for conversion of the coordinate values of the color space.
Although not included in the foregoing Aspect 2, the technology also include a case in which one profile to be used to convert the first coordinate values to the second coordinate values is not accepted.
As exemplified in
As exemplified in
As exemplified in
Here, the adjustment range is not limited to a part of the first color space and may be the whole first color space.
Although not included in the foregoing Aspect 5, the technology also includes a case in which the adjustment range is fixed.
As exemplified in
Here, in the profile adjustment step ST7, the adjustment target profile 550 may be adjusted by repeating a calculation process of approaching the obtained second coordinate values to the target output values TargetOut.
Although not included in the foregoing Aspect 6, the technology also include adjusting the adjustment target profile so that the third coordinate values of the profile connection space or the first coordinate values of the first color space are closed to the target values.
As exemplified in
As exemplified in
As exemplified in
Here, the rendering intent includes, for example, “Perceptual”, “Media-Relative Colorimetric”, “Absolute Colorimetric”, and “Saturation”. For example, two or more kinds of rendering intents of the four kinds of rendering intents may be set as designation targets.
Although not included in the foregoing Aspect 9, the technology also includes a case in which no designation intent is accepted.
Incidentally, according to an aspect of the technology, a profile adjustment method is a profile adjustment method of causing a computer that includes a central processing device (for example, the CPU 111) and a memory (for example, the ROM 112 and the RAM 113) to adjust the profile 500 defining a correspondent relation between input coordinate values of the input color space CS4 and output coordinate values of the output color space CS5. The profile adjustment method includes a color space selection step ST3, the target acceptance step ST4, and the profile adjustment step ST7. In the color space selection step ST3, one of two or more kinds of color spaces is accepted as an adjustment target color space CS6 among the input color space CS4, the output color space CS5, and the profile connection space CS3 when the input color space CS4 and the output color space CS5 are not the profile connection space CS3. In the target acceptance step ST4, an adjustment target T0 at coordinates at which an adjustment target color (for example, an adjustment point P0) is expressed in the adjustment target color space CS6 is accepted. In the profile adjustment step ST7, the profile 500 is adjusted based on the accepted adjustment target T0.
In the foregoing Aspect 10, the adjustment target of the coordinate values of the profile can be selected from two or more kinds of color spaces among the coordinate values of the input color space CS4 in the profile, the coordinate values of the output color space CS5 in the profile, and the profile connection space CS3 when the input color space CS1 and the output color space CS2 are not the profile connection space CS3. Accordingly, this aspect can provide the technology for improving convenience of work for adjusting the profile used to convert the coordinate values of the color space.
Here, the input color space includes a CMYK color space, a CMY color space, an RGB color space, a CIE Lab color space, and a CIE XYZ color space.
The output color space includes a CMYK color space, a CMY color space, an RGB color space, a CIE Lab color space, and a CIE XYZ color space.
As exemplified in
Here, in the profile adjustment step ST7, the profile 500 may be adjusted by repeating a calculation process of approaching the obtained output coordinate values to the target output values TargetOut.
Although not included in the foregoing Aspect 11, the technology also includes adjusting the profile so that the input coordinate values are close to the target values.
As exemplified in
Although not included in the foregoing Aspect 12, the technology also includes a case in which there is no option described above.
Incidentally, according to an aspect of the technology, a profile adjustment program PRO causes a computer to realize functions corresponding to the steps of Aspect 1, that is, an adjustment target profile designation function FU2 corresponding to the adjustment target profile designation step ST2, a target acceptance function FU4 corresponding to the target acceptance step ST4, and a profile adjustment function FU7 corresponding to the profile adjustment step ST7. Accordingly, this aspect can provide the profile adjustment method capable of improving convenience of work for adjusting the profile used to convert the coordinate values of the color space. The profile adjustment program may also cause a computer to realize a profile selection function FU1 corresponding to the profile selection step ST1, a color space selection function FU3 corresponding to the color space selection step ST3, an adjustment range designation function FU5 corresponding to the adjustment range designation step ST5, and an intent designation function FU6 corresponding to the intent designation step ST6.
According to another aspect of the technology, the profile adjustment program PRO causes a computer to functions corresponding to the steps of Aspect 10, that is, the color space selection function FU3 corresponding to the color space selection step ST3, the target acceptance function FU4 corresponding to the target acceptance step ST4, and the profile adjustment function FU7 corresponding to the profile adjustment step ST7. This aspect can provide the profile adjustment program improving convenience of the work for adjusting the profile used to convert the coordinate values of the color space.
Further, according to an aspect of the technology, a profile adjustment device (included in, for example, a host device 100) includes units corresponding to the steps of Aspect 1, that is, an adjustment target profile designation unit U2 corresponding to the adjustment target profile designation step ST2, a target acceptance unit U4 corresponding to the target acceptance step ST4, and a profile adjustment unit U7 corresponding to the profile adjustment step ST7. This aspect can provide a profile adjustment device improving convenience of the work for adjusting the profile used to convert the coordinate values of the color space. The profile adjustment device may include a profile selection unit U1 corresponding to the profile selection step ST1, a color space selection unit U3 corresponding to the color space selection step ST3, an adjustment range designation unit U5 corresponding to the adjustment range designation step ST5, and an intent designation unit U6 corresponding to the intent designation step ST6.
Further, according to another aspect of the technology, a profile adjustment device (included in, for example, the host device 100) includes units corresponding to the steps of Aspect 10, that is, the color space selection unit U3 corresponding to the color space selection step ST3, the target acceptance unit U4 corresponding to the target acceptance step ST4, and the profile adjustment unit U7 corresponding to the profile adjustment step ST7. This aspect can provide a profile adjustment device improving convenience of the work for adjusting the profile used to convert the coordinate values of the color space.
Further, according to an aspect of the technology, a profile adjustment system includes a printing device (for example, a printer 200) that prints a color chart including a patch, a color measurement device 117 that measures color of the patch, and the units U2, U4, and U7 of Aspect 15. The system can set the adjustment target T0 based on the measurement color values of the patch of the color chart printed using the profile 500 including the adjustment target profile 550 and can use the measurement color values for adjusting the adjustment target profile 550. This aspect can provide the profile adjustment system improving convenience of the work for adjusting the profile used to convert the coordinate values of the color space. The profile adjustment system may include the profile selection unit U1, the color space selection unit U3, the adjustment range designation unit U5, and the intent designation unit U6.
Further, according to another aspect of the technology, a profile adjustment system includes a printing device (for example, the printer 200) that prints a color chart including a patch, the color measurement device 117 that measures color of the patch, and the units U3, U4, and U7 of Aspect 16. The system can set the adjustment target T0 based on the measurement color values of the patch of the color chart printed using the profile 500 and can use the measurement color values for adjusting the profile 500. This aspect can provide the profile adjustment system improving convenience of the work for adjusting the profile used to convert the coordinate values of the color space.
Further, the technology can be applied to a method of controlling the profile adjustment device, a complex system including the profile adjustment device, a method of controlling the complex system, a program controlling the profile adjustment device, a program controlling the complex system, a profile adjustment program, and a computer-readable medium recording the control program. The above-described device may be configured with a plurality of distributed portions.
The storage device 114 stores an operating system (OS) (not illustrated), a profile adjustment program PRO, and the like. The operating system, the profile adjustment program PRO, and the like are appropriately read to the RAM 113 to be used for adjustment process for a profile 500. Here, the profile 500 is a generic term of an input profile 610, an output profile 620, and a device link profile 630. At least one of the RAM 113 and the storage device 114 stores various kinds of information, for example, the input profile 610, the output profile 620, the device link profile 630, and adjustment history 700. A nonvolatile semiconductor memory such as a flash memory or a magnetic storage device such as a hard disk can be used as the storage device 114.
A liquid crystal panel or the like can be used as the display device 115. A pointing device, a hard key including a keyboard, a touch panel attached on the surface of a display panel, or the like can be used as the input device 116. The color measurement device 117 can measure each color patch formed on a print substrate which is an example of a medium on which a color chart is formed and can output the color measurement values. The patch is also called a color chart. Color measurement values are considered as, for example, values indicating lightness L and chromaticity coordinates a and b in a CIE Lab color space. The color measurement device 117 may be installed out of the host device 100. The host device 100 acquires color measurement data including a plurality of color measurement values from the color measurement device 117 and executes various processes. The communication I/F 118 is connected to a communication I/F 210 of a printer 200 and inputs and outputs information such as printing data to the printer 200. As the standard of the communication I/F 118 and the communication I/F 210, a universal serial bus (USB), a short-range radio communication standard, or the like can be used. The communication of the communication I/F 118 and the communication I/F 210 may be wired or wireless or may be network communication such as a local area network (LAN) or the Internet.
The profile adjustment program PRO illustrated in
The host device 100 includes a computer such as a personal computer (including a tablet terminal). The host device 100 may include all the constituent elements 111 to 118 within a single casing and may also be configured as a plurality of devices separated to be able to communicate with each other. Even when the printer is the host device 100, the technology can be embodied.
The printer 200 illustrated in
Next, an example of a color management system to which the technology can be applied will be described with reference to
In the color management system illustrated in
The target printer 300 is assumed to be an offset printer, but a gravure printer, a flexographic printer, or the like may be used. The target color Ct is expressed with, for example, coordinate values (Lab values) of the CIE Lab color space.
The RIP 400 includes the input profile 610, the output profile 620, and a color library 640. The input profile 610 is a file that describes color characteristics of ink used by the target printer 300. The output profile 620 is a file that describes color characteristics of ink used by the ink jet printer 200. For both the profiles 610 and 620, for example, a data format of an ICC profile can be used. The process colors CMYKin of the printing document data D0 are converted into colors Labs of the Lab color space according to the input profile 610 and are converted into printing colors cmykp according to the output profile 620. When the printer 200 uses ink of a total of four colors of CMYK, the printing colors cmykp are output to the printer 200 to be reproduced on a printing matter.
When the names of colors are set in the printing document data D0, the RIP 400 converts the names of the colors into the colors Labs of the Lab color space with reference to the color library 640 in some cases.
The RIP 400 has not only the process colors CMYKin but also, for example, process colors expressing use amounts of color materials of only the three primary colors CMY (referred to as CMYin) which are subtractive mixture of colors or process colors expressing intensities of the three primary colors red (R), green (G), and blue (B) (referred to as RGBin) which are additive mixture of colors, and an input profile for converting coordinate values of the Lab color space. Accordingly, the RIP 400 can convert the process colors CMYin or the process colors RGBin into the printing colors cmykp via the Lab color space. In addition, the RIP 400 can also input the colors Labs of the Lab color space and convert the colors Labs into the printing colors cmykp.
As described above, colors close to colors of the target printer 300 can be reproduced by the ink jet printer 200. However, actually, expected colors may not be reproduced due to an error of a profile, a color measurement error, a variation in a printer, or the like in some cases. In these cases, conversion precision of target colors is improved by correcting the profiles 610 and 620. When the output profile 620 is corrected, it is considered that Labs values in a profile connection space (PCS) are set as target values, color differences between both the colors are calculated using results (Labp) obtained by measuring colors printed by the printer 200 as current values, and the output profile 620 is corrected to reduce the color differences. When the input profile 610 is corrected, it is considered that data of the color chart is converted into the input profile 610 and the output profile 620, the color chart is printed, color differences between color measurement results (Labp) of each patch and target saturation values (Labt) are calculated, and the input profile 610 is corrected to reduce the color differences.
Here, expected colors may not be obtained or it takes some time due to the following reasons.
Reason 1: Since it is necessary to measure colors of printed results, a measurement instrument is necessary and color matching countermeasure may not be taken visually.
Reason 2: When the input profile 610 is corrected, a calculation result of the color differences is fed back to the input profile 610. However, when it is considered that there is a reason of an error in the output profile 620, it is necessary to also correct another input profile. (In this case, by feeding the calculation result back to the output profile 620 and correcting the output profile 620, it is not necessary to correct another output profile.)
In the specific example, the functions FU1 to FU7 realized by the profile adjustment program PRO improve convenience of work for adjusting a profile used to convert coordinate values of the color space and realize further higher color reproduction precision or a gradation property.
As illustrated in
The output profile 620 is data that defines a correspondent relation between Lab values (Lj, aj, bj) of the Lab color space (CS3) and cmyk values (cj, mj, yj, kj) of the cmyk color space (which is example of a second color space CS2) suitable for ink used by the ink jet printer 200. In this case, lattice points GD2 of a B2A table are normally arranged at a substantially equal interval in an L-axis direction, an a-axis direction, and a b-axis direction in the Lab color space. Here, the variable j is a variable for identifying the lattice points GD2 set in the Lab color space (CS3). The reason for expression as the “cmyk color space” is to distinguish a color space suitable for ink used by the printer 200 from a color space suitable for ink used by the target printer 300. The cmyk values are examples of second coordinate values. In the output profile 620, the Lab color space (CS3) is an example of an input color space CS4 and the cmyk color space (CS2) is an example of an output color space CS5.
The device link profile 630 is data that defines a correspondent relation between CMYK values (Ci, Mi, Yi, Ki) of the CMYK color space (CS1) and cmyk values (ci, mi, yi, ki) of an cmyk color space (CS2). Here, the variable i is a variable for identifying the lattice points GD1 set in the CMYK color space (CS1). The device link profile 630 can be obtained by linking the input profile 610 and the output profile 620. In the input profile 610, the CMYK color space (CS1) is an example of an input color space CS4 and the cmyk color space (CS2) is an example of an output color space CS5.
An A2Bx tag (x is 0, 1, or 2 illustrated in
The A2B0 tag and the B2A0 tag illustrated in
When the profile adjustment process illustrated in
The host device 100 ends the profile and parameter setting process when the input device 116 accepts an operation on the above-described fields and the buttons (S210) and an operation on the adjustment execution button 870 is accepted. The process of S210 includes the following processes S211 to S216:
(S211) a process of accepting selection of one of a combination of the profiles to be used for the change from the CMYK values to the cmyk values and one profile which is an adjustment target profile 550 to be used for the conversion from the CMYK values to the cmyk values;
(S212) a process of receiving one of the profiles 610, 620, and 630 as the adjustment target profile 550;
(S213) a process of accepting one of two or more kinds of color spaces among the CMYK color space (CS1), the cmyk color space (CS2), and the Lab color space (CS3) as an adjustment target color space CS6;
(S214) a process of accepting an input of the adjustment target T0 at coordinates expressing the adjustment point P0 (which is an example of the adjustment target color);
(S215) a process of accepting designation of an adjustment range in which a profile is adjusted based on the target T0 is the adjustment target profile 550 in the CMYK color space (CS1); and
(S216) a process of accepting one of a plurality of rendering intents for defining a correspondent relation of the adjustment target profile 550 as a designated intent.
First, the process of S211 will be described with reference to
The host device 100 accepts an operation of selecting a profile from the profiles 500 stored in the storage device 114 when the input device 116 accepts an operation on the selection fields 811 to 813.
In the input profile selection field 811, an input profile to be used for color conversion can be selected from the input profile 610 stored in the storage device 114 when the input profile 610 is used for the color conversion. When the input profile 610 is not used for the color conversion, the input profile selection field 811 may be set as a blank.
In the output profile selection field 812, an output profile to be used for the color conversion can be selected in the output profile 620 stored in the storage device 114 when the output profile 620 is used for the color conversion. When the output profile 620 is not used for the color conversion, the output profile selection field 812 may be set as a blank.
In the device link profile selection field 813, a device link profile to be used for the color conversion can be selected in the device link profile 630 stored in the storage device 114 when the device link profile 630 is used for the color conversion. When the device link profile 630 is not used for the color conversion, the device link profile selection field 813 may be set as a blank.
As illustrated in
As illustrated in
As described above, one of the combination of the profiles to be used for the color conversion and one profile which is the adjustment target profile 550 to be used for the color conversion is selected in the selection fields 811 to 813.
Next, the process of S212 will be described with reference to
The host device 100 executes a process of changing a designated item of the adjustment target profile designation profile 820 in response to the selection in the above-described selection fields 811 to 813.
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As described above, when the combination of the input profile 610 and the output profile 620 is selected, one of the profiles 610, 620, and 630 is designated as the adjustment target profile 550 in the adjustment target profile designation field 820.
In the adjustment target profile designation field 820, validation or invalidation of an operation on the above-described selection fields 811 to 813 may be controlled in response to the selection so that the input profile 610, the output profile 620, and the device link profile 630 can all be selected as the adjustment target.
Further, the process of S213 will be described with reference to
The host device 100 executes a process of changing a selection item of the adjustment target color space selection field 830 in response to selection on the above-described selection fields 811 to 813.
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As described above, one color space of two or more kinds of color spaces among the CMYK color space (CS1), the cmyk color space (CS2), and the Lab color space (CS3) is selected as the adjustment target color space CS6.
Further, the process of S214 will be described with reference to
The host device 100 executes a process of changing an input item of the target acceptance region 840 in response to selection in the above-described fields 811 to 813 and 830. The host device 100 executes a process of changing an input item of the target acceptance region 840 in response to selection in the adjustment data selection field 845.
As illustrated in
When the “absolute value” is selected in the adjustment data selection field 845, as illustrated in
When the “relative value” is selected in the adjustment data selection field 845, as illustrated in
As illustrated in
For example, when an operation on the button 841 of “designate from image” on the UI screen 800 illustrated in
When an operation on the history load button 881 is accepted, the host device 100 reads the adjustment history 700 of the adjustment stored in the storage device 114 and adds the adjustment history 700 in the target acceptance region 840. When an operation on the history save button 882 is accepted, the host device 100 stores information regarding the target acceptance region 840 as the adjustment history 700 in the storage device 114.
The adjustment target T0 accepted in the target acceptance region 840 is changed as follows depending on selected content of the adjustment target color space selection field 830 and selected content of the adjustment data selection field 845.
(Selected Content 1) The CMYK color space is selected as the adjustment target color space CS6 and the “absolute value” is selected as an input of the adjustment target T0. In this case, the input of the adjustment target T0 is the CMYK values (which are assumed to be T_C, T_M, T_Y, T_K). The CMYK values are expressed in, for example, 0 to 100%.
(Selected Content 2) The CMYK color space is selected as the adjustment target color space CS6 and the “relative value” is selected as an input of the adjustment target T0. In this case, the input of the adjustment target T0 is differences (which are assumed to be ΔC, ΔM, ΔY, ΔK) of the target values (T_C, T_M, T_Y, T_K) of the current values (C_C, C_M, C_Y, C_K) of the CMYK values.
(Selected Content 3) The Lab color space is selected as the adjustment target color space CS6 and the “absolute value” is selected as an input of the adjustment target T0. In this case, the input of the adjustment target T0 is the Lab values (which are assumed to be T_L, T_a, T_b).
(Selected Content 4) The Lab color space is selected as the adjustment target color space CS6 and the “relative value” is selected as an input of the adjustment target T0. In this case, the input of the adjustment target T0 is differences (which are assumed to be ΔL, Δa, and Δb) of the target values (T_L, T_a, T_b) of the current values (C_L, C_a, C_b) of the Lab values.
(Selected Content 5) The cmyk color space is selected as the adjustment target color space CS6 and the “absolute value” is selected as an input of the adjustment target T0. In this case, the input of the adjustment target T0 is the cmyk values (which are assumed to be T_c, T_m, T_y, T_k). The cmyk values are expressed in, for example, 0 to 100%.
(Selected Content 6) The cmyk color space is selected as the adjustment target color space CS6 and the “relative value” is selected as an input of the adjustment target T0. In this case, the input of the adjustment target T0 is differences (which are assumed to be Δc, Δm, Δy, Δk) of the target values (T_c, T_m, T_y, T_k) of the current values (C_c, C_m, C_y, C_k) of the cmyk values.
As described above, the adjustment target T0 is accepted at the coordinates indicating the adjustment point P0 in the adjustment target color space CS6.
Further, the process of S215 will be described with reference to
The host device 100 accepts designation of whether the adjustment range A0 adjusted based on the adjustment target T0 is the whole color space in the adjustment range designation field 850. A plurality of designation items of the adjustment range designation field 850 illustrated in
As described above, the adjustment range A0 is set in the adjustment target profile 550 in the first color space CS1.
Further, the process of S216 will be described with reference to
The host device 100 accepts designation of a rendering intent for defining a correspondent relation of the adjustment target profile 550 in the intent designation field 860. A plurality of designation items of the intent designation field 860 illustrated in
As described above, one of the plurality of rendering intents for defining the correspondent relation of the adjustment target profile 550 is accepted as a designation intent.
When the operation on the adjustment execution button 870 illustrated in
First, the host device 100 obtains current output values CurrentOut according to the color conversion profile (including a combination of the profiles) designated in the profile selection fields 811 to 813 at each adjustment point P0 input in the target acceptance region 840 (S104). This is because the adjustment is executed using the output colors cmykp corresponding to the colors of the output image IMO formed on the print substrate ME1 as a reference. When there is information appropriate for the designation intent in the profile, the color conversion is executed according to the information appropriate for the designation intent.
For example, as illustrated in
Here, as illustrated in
In the foregoing (a-1) case, the adjustment target profile 550 automatically becomes the input profile 610 and the current output values CurrentOut can be calculated by the following expression (see
CurrentOut=ficc(InputProfile,A2B,Input).
As illustrated in
In the foregoing (a-2) case, the adjustment target profile 550 automatically becomes the output profile 620 and the current output values CurrentOut can be calculated by the following expression (see
CurrentOut=ficc(OutputProfile,B2A,Input).
As illustrated in
In the foregoing (a-3) case, the adjustment target profile 550 automatically becomes the device link profile 630 and the current output values CurrentOut can be calculated by the following expression (see
CurrentOut=ficc(DLProfile,A2B0,Input).
As illustrated in
In the foregoing (b-1) and (b-2) cases, when the adjustment target profile 550 is the input profile 610 or the output profile 620, the current output values CurrentOut can be calculated by the following expression (see
CurrentOut=ficc(OutputProfile,B2A,ficc(InputProfile,A2B,Input)).
After the current output values CurrentOut are calculated, the host device 100 obtains the target output values TargetOut according to the color conversion profile (including the combination of the profiles) designated in the profile selection fields 811 to 813 and the adjustment target color space CS6 designated in the adjustment target color space selection field 830 at each adjustment point P0 input in the target acceptance region 840 (S106). This is because the adjustment is executed using the output colors cmykp corresponding to the colors of the output image IMO formed on the print substrate ME1 as a reference. When there is the information appropriate for the designation intent in the profile, the color conversion is executed according to the information in accordance with the designation intent.
For example, as illustrated in
In the foregoing (a-1-1) case, the target output values TargetOut can be calculated by the following expression (see
TargetOut=ficc(InputProfile,A2B,Input+AdjustData).
As illustrated in
In the foregoing (a-1-2) case, the target output values TargetOut can be calculated by the following expression (see
TargetOut=ficc(InputProfile,A2B,Input)+AdjustData.
As illustrated in
In the foregoing (a-2-1) case, the target output values TargetOut can be calculated by the following expression (see
TargetOut=ficc(OutputProfile,B2A,Input+AdjustData).
As illustrated in
In the foregoing (a-2-2) case, the target output values TargetOut can be calculated by the following expression (see
TargetOut=ficc(OutputProfile,B2A,Input)+AdjustData.
When the device link profile 630 is designated for the color conversion and the input color space CS4 is designated in the adjustment target color space CS6 (a-3-1), the adjustment amounts AdjustData is added to the CMYK values (Cp, Mp, Yp, Kp) in the CMYK color space. The adjustment amounts AdjustData are expressed with relative values (ΔCp, ΔMp, ΔYp, ΔKp). In the CMYK color space, the CMYK values after the adjustment are expressed as (Cp+ΔCp, Mp+ΔMp, Yp+ΔYp, Kp+ΔKp).
In the foregoing (a-3-1) case, the target output values TargetOut can be calculated by the following expression (see
TargetOut=ficc(DLProfile,A2B0,Input+AdjustData).
When the device link profile 630 is designated for the color conversion and the output color space CS5 is designated in the adjustment target color space CS6 (a-3-2), the adjustment amounts AdjustData are added to the cmyk values (cp, mp, yp, kp) in the cmyk color space. The adjustment amounts AdjustData are expressed with relative values (Δcp, Δmp, Δyp, Δkp). In the cmyk color space, the cmyk values after the adjustment are expressed as (cp+Δcp, mp+Δmp, yp+Δyp, kp+Δkp).
In the foregoing (a-3-2) case, the target output values TargetOut can be calculated by the following expression (see
TargetOut=ficc(DLProfile,A2B0,Input)+AdjustData.
Although not illustrated, the Lab colors space may also be assumed to be designated in the adjustment target color space CS6. In this case, the Lab color space is the output color space CS5 in the input profile 610 and is the input color space CS4 in the output profile 620. The target output values TargetOut can be calculated, for example, by referring to the output profile used to generate the device link profile 630.
As illustrated in
In the foregoing (b-1-1) case, the target output values TargetOut can be calculated by the following expression (see
TargetOut=ficc(OutputProfile,B2A,ficc(InputProfile,A2B,Input+AdjustData)).
The foregoing expression is the same even when the adjustment target profile 550 is the output profile 620.
As illustrated in
In the foregoing (b-1-2) case, the target output values TargetOut can be calculated by the following expression (see
TargetOut=ficc(OutputProfile,B2A,ficc(InputProfile,A2B,Input))+AdjustData.
The foregoing expression is the same even when the adjustment target profile 550 is the output profile 620.
As illustrated in
In the foregoing (b-1-3) case, the target output values TargetOut can be calculated by the following expression (see
TargetOut=ficc(OutputProfile,B2A,ficc(InputProfile,A2B,Input)+AdjustData).
The foregoing expression is the same even when the adjustment target profile 550 is the output profile 620.
The calculation of the target output values TargetOut can be omitted when the adjustment target T0 is expressed with the output coordinate values. The calculation of the target output values TargetOut can be executed when the adjustment target T0 is not expressed with the output coordinate values.
After the target output values TargetOut are calculated, the host device 100 acquires the input values Input_P and the adjustment target values TargetOut_P at each adjustment point P0 in the adjustment target profile 550 (S108). This is because the correspondent relation between the input values and the output values in the adjustment target profile 550 is adjusted. When there is information regarding the designation intent in the profile, the color conversion is executed according to the information appropriate for the designation intent.
In the (a-1), (a-2), and (a-3) cases illustrated in
Input_P=Input; and
TargetOut_P=TargetOut.
The current output values CurrentOut_P in the adjustment target profile 550 are the current output values CurrentOut of the designated profile:
CurrentOut_P=CurrentOut
When the relative value of the adjustment target T0 is expressed in the output color space CS5 of the adjustment target profile 550, TargetOut_P−CurrentOut_P is set.
As illustrated in
Input_P=Input; and
TargetOut_P=ficc(OutputProfile,A2B,TargetOut).
The reason why the adjustment target values TargetOut_P (the Lab values) of the adjustment target profile 550 are obtained from the target output values TargetOut (the cmyk values) is to execute the adjustment using the output colors cmykp corresponding to the colors of the output image IMO as a reference.
The current output values CurrentOut_P (the Lab values) in the adjustment target profile 550 are expressed in the following expression:
CurrentOut_P=ficc(InputProfile,A2B,Input).
The relative values of the adjustment target T0 are expressed in the output color space CS5 of the adjustment target profile 550, TargetOut_P−CurrentOut_P is set.
As illustrated in
Input_P=ficc(InputProfile,A2B,Input); and TargetOut_P=TargetOut.
The current output values CurrentOut_P (the cmyk values) in the adjustment target profile 550 are the current output values CurrentOut of the combination of the profiles 610 and 620:
CurrentOut_P=CurrentOut.
When the relative values of the adjustment target T0 are expressed in the output color space CS5 of the adjustment target profile 550, TargetOut_P−CurrentOut_P is set.
After the input values Input_P in the adjustment target profile 550 and the adjustment target values TargetOut_P are acquired, the host device 100 adjusts the adjustment range A0 of the adjustment target profile 550 based on the adjustment target T0 in S110 to S112.
First, the concept that the adjustment target profile 550 is adjusted in the adjustment range A0 will be described with reference to
The adjustment range A0 is set in the adjustment amounts AdjustData through an input to the adjustment range designation field 850 and the target acceptance region 840 illustrated in
The above-described correction is executed on all the coordinate axes of the input color space CS4 and all the coordinate values of the output color space CS5.
Next, an example in which the adjustment amounts AD is set at each lattice point GD0 of the adjustment range A0 will be described with reference to
As illustrated in
After the host device 100 determines the adjustment amounts AD1 of the output values at the nearest lattice point GDnearest, as illustrated in
Of course, the technology is not limited to the spline functions used for the interpolation calculation.
After the adjustment amounts AD of the output values at each lattice point of the adjustment range A0 is determined, the host device 100 reflects the determined adjustment amounts AD in the adjustment target profile 550 (S114 of
In this way, the correspondent relation of the adjustment target profile 550 is adjusted so that the current output values CurrentOut in the second color space CS2 are close to the target output values TargetOut. When there is the information appropriate for the designation intent in the adjustment target profile 550, the adjustment target profile 550 is adjusted in the correspondent relation appropriate for the designation intent.
After the adjustment target profile 550 is updated, the host device 100 obtains the current output values CurrentOut using the adjustment target profile 550 after the updating or the combination of the profiles including the adjustment target profile 550 after the updating at each adjustment point P0 input in the target acceptance region 840 (S116). The current output values CurrentOut after the updating can be calculated using the same expression as the process of S104 described with reference to
The host device 100 obtains differences d between the current output values CurrentOut after the updating and the target output values TargetOut at each adjustment point P0 input in the target acceptance region 840 (S118). For example, the differences can be Euclid distances between points corresponding to the output values CurrentOut in the output color space CS5 of the adjustment target profile 550 and points corresponding to the target output values TargetOut.
In addition, the host device 100 determines whether an end condition of the repeated processes of S108 to S120 is established (S120). When the end condition is not established, the processes of S108 to S120 are repeated. When the end condition is established, the profile adjustment process ends. For example, when the differences d at all the adjustment points P0 are equal to or less than predetermined thresholds, the end condition can be established. When the repeated process reaches a specified number of times, the end condition may be established.
As described above, the adjustment target profile 550 is adjusted so that the current output values CurrentOut obtained from the input coordinate values corresponding to the adjustment point P0 according to the current adjustment target profile 550 or the combination of the profiles including the adjustment target profiles 550 are closed to the target output values TargetOut. In this way, since the adjustment target profile 550 is adjusted using the coordinate values indicating the output colors cmykp as the reference, the profile used to convert the coordinate values of the color space can be adjusted with good color reproduction precision in the specific example. At this time, since the adjustment target profile 550 or the adjustment target color space CS6 can be designated, the specific example can flexibly correspond to a use environment of a user.
For example, when color conversion is executed, it is preferable to combine the input profile and the output profile for use in color conversion. On the other hand, when color reproduction precision of a single profile is desired to be improved as in spot color matching or the like, it is preferable to use the single profile for color conversion. In the specific example, since the combination of the profiles and the single profile for the color conversion can be switched, convenience can be achieved.
When the profiles are combined to adjust the profile, the adjustment target profile is desired to be set as the input profile in some cases and is desired to be set as the output profile in some cases. When a reason of color difference arise in the input profile, the input profile can be set as the adjustment target, and thus it is not necessary to separately adjust the output profile such as printer profile of another print substrate. When a reason of an error is considered to arrive in the output profile, the output profile can be adjusted, and thus it is not necessary to separately adjust another input profile.
Further, for example, the following procedure can be considered as a procedure in which the user adjusts the profile. Specific examples can correspond to all the procedures.
(Procedure 1) It is assumed that there is a color sample indicating a target color for a user who desires to visually match colors without using a colorimeter. There is a mixing color chart data indicating a mixing color chart in which surrounding colors of a color desired to be matched are disposed, the mixing color chart data is converted into an input profile and an output profile, and the mixing color chart is printed. The user selects a patch closest to a target color in the mixing color chart to obtain CMYK values that form the patch. The profiles are adjusted setting the CMYK values as a target in the CMYK color space.
(Procedure 2) It is assumed that there is a color sample indicating a target color for a user who desires to visually match colors without using a colorimeter. A mixing color chart in which output data (cmykp) and surrounding colors in a combination of a current profile with input data (CMYKin) of the color desired to be matched are disposed is printed. The user selects a patch closest to a target color in the mixing color chart to obtain cmyk values that form the patch. The profiles are adjusted setting the cmyk values as a target in the cmyk color space.
As exemplified above, the specific examples can provide the technology for improving convenience of work for adjusting a profile to be used to convert the coordinate values of the color space.
Various modification examples of the invention can be considered.
For example, an output device is not limited to an ink jet printer, but may be an electrographic printer such as a laser printer, a 3-dimensional printer, a display device, or the like.
The kinds of color materials for forming an image are not limited to C, M, Y, and K, but may include Lc, Lm, dark yellow (Dy) with higher density than Y, orange (Or), green (Gr), light black (Lk) with lower density than K, unpigmented color materials for image quality improvement, or the like in addition to C, M, Y, and K.
Of course, the second color space is not limited to the cmyk color space, but may be the CMY color space, the RGB color space, or the like.
A target device is not limited to a target printer, but may be a display device or the like.
Of course, the first color space is not limited to the CMYK color space, but may be the CMY color space, the RGB color space, or the like.
The host device 100 may convert the color of the adjustment point P0 into the cmyk values according to the profile 500 including the adjustment target profile 550, cause the color measurement device 117 to measure colors of a patch by causing the ink jet printer 200 to print the color chart including the patch of the colors expressed with the cmyk values, and acquire measurement color values of the patch from the color measurement device 117. The measurement color values can be used to determine the adjustment target T0 input in the target acceptance region 840 illustrated in
Further, the host device 100 may add the color measurement values from the color measurement device 117 when the adjustment target profile 550 is adjusted. When the processes of S108 to S120 in the profile adjustment process illustrated in
The selection from the adjustment target profile designation field 820 illustrated in
The color spaces which can be selected as the adjustment target color space are not limited to the three kinds of color spaces, the first color space, the second color space, and the profile connection space, but may be two kinds of color spaces, the first color space and the second color space, may be two kinds of color spaces, the first color space and the profile connection space, or may be two kinds of color spaces, the second color space and the profile connection space.
Even when the profiles are combined necessarily for the color conversion, it is possible to obtain the basic operational effects and the advantages of Aspect 1 included in the technology.
When one of the input color space and the output color space is accepted as the adjustment target color space to adjust the profiles despite no combination of the profiles for the color conversion, it is possible to obtain the basic operational effects and the advantages of Aspect 10 of the technology.
As described above, according to the various aspects of the invention, it is possible to provide the technology or the like for improving convenience of work for adjusting a profile to be used to convert coordinate values of a color space. Of course, even in a technology realized by only constituent factors according to the independent claims, it is possible to obtain the above-described basic operational effects and advantages.
It is also embody configurations in which configurations disclosed in the above-described examples are substituted or combinations thereof are changed and configurations in which configurations disclosed in the known technologies and the above-described examples are substituted or combinations thereof are changed. The invention also includes such configurations.
This application claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2017-111410, filed Jun. 6, 2017. The entire disclosure of Japanese Patent Application No. 2017-111410 is hereby incorporated herein by reference.
Number | Date | Country | Kind |
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2017-111410 | Jun 2017 | JP | national |