JP2006168007A - Image processing device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for outputting an image depending on a purpose in such a manner that whether importance is placed on the weather resistance or importance is placed on the coloring property is selected, and when the importance is placed on the weather resistance, the using amount of an ink having less weather resistance is suppressed, and on the contrary, when the importance is placed on the coloring property, the using amount of an ink of which the coloring property is good even though having less weather resistance is increased. <P>SOLUTION: This image processing device is equipped with an image inputting means which inputs an image, a printing quality setting means for determining on which one of the weather resistance and the coloring property the importance is placed in an output image, and an LUT selecting means which selects LUT from a set value by the printing quality setting means. The image processing device is also equipped with a color converting means which converts the color of the input image using the LUT selected by the LUT selecting means, and an image outputting means which outputs an image color-converted by the color converting means. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image processing apparatus and method capable of controlling weather resistance.

  In recent inkjet printers, in order to widen the color reproduction range (hereinafter referred to as the color gamut), the color materials used for the ink are improved, and C (cyan), M (magenta), Y (yellow), K (black) A method of printing by adding inks of other hues (hereinafter referred to as special color inks) has been developed. However, when developing a new ink, the color development property and the characteristic that the color tone does not change even when exposed to light or ozone for a long time (hereinafter referred to as weather resistance) are also important problems. Yes. That is, if the reproducible color formed by mixing inks in a multicolor printer and the weather resistance of only specific ink is bad, the color tone of the reproducible color will change.

In order to solve the above problem, Patent Document 1 discloses an ink jet recording ink, an ink jet recording ink set, and the ink jet recording ink or ink jet which are excellent in light resistance, can suppress bleeding and can form a high quality ink jet image. An ink jet recording method using a recording ink set is described.
JP2003-231833

  However, the method of Patent Document 1 has a problem in that every time a new ink is developed, the examination must be repeated at an enormous cost for improving the weather resistance.

  The present invention has been made in view of the above problems, and selects whether to place importance on weather resistance or color development. If the weather resistance is important, the amount of ink having poor weather resistance is used. In contrast, when the emphasis is on color development, an object of the present invention is to provide a method of outputting an image according to the purpose by increasing the amount of ink with good color development even if the weather resistance is poor.

  In order to achieve the above object, the present invention provides an image input unit for inputting an image, a print quality setting unit for determining whether weather resistance or color development is important in an output image, and a set value by the print quality setting unit. An LUT selection unit that selects an LUT based on the LUT, a color conversion unit that converts the color of the input image using the LUT selected by the LUT selection unit, and an image that outputs an image color-converted by the color conversion unit Output means.

  According to the present invention, it is selected whether importance is attached to weather resistance or color development. When weather resistance is important, the amount of ink having poor weather resistance is suppressed. It is possible to provide a method for outputting an image according to the purpose by increasing the amount of ink that has good color development even if the property is poor.

(First embodiment)
Hereinafter, an embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing a configuration of an image processing apparatus according to an embodiment of the present invention. 1 is an image processing apparatus according to an embodiment of the present invention. Reference numeral 2 denotes a print quality setting unit for setting a print quality, such as a PC connected to the outside or a UI installed in the printer main body, which determines whether weather resistance or color development is important. An image data storage unit 3 stores image information to be output, such as a hard disk or a CD-ROM. 4 is an image input unit for reading image data from the image data storage unit 3 into the image processing apparatus 1. Reference numeral 5 denotes an LUT selection unit for selecting an LUT to be used for color conversion based on the set value based on the print quality set by the print quality setting unit 2. An LUT storage unit 6 stores an LUT used for color conversion. A color conversion unit 7 performs color conversion processing on the image input by the image input unit 4 using the LUT stored in the LUT storage unit 6. 8 is an image output unit for outputting the image data converted by the color conversion unit 7. Reference numeral 9 denotes an image output device such as an ink jet printer that actually performs printing based on the image data output from the image output unit 8.

<Overall processing>
Here, FIG. 2 is a flowchart of image processing performed in the image processing apparatus 1. Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings. First, in S201, the image input unit 4 reads image data from the image data storage unit 3 into the image processing apparatus 1. Next, in S202, the print quality setting unit 2 uses the user interface (hereinafter referred to as UI) as shown in FIG. Set. In S203, the LUT selection unit 5 uses a lot of spot color ink from the LUTs stored in the LUT storage unit 6 on the basis of the print quality set in S202, or an LUT that emphasizes color development or a spot color ink. The most suitable color conversion LUT is selected from the LUTs that suppress use and emphasize weather resistance. In S204, the color conversion unit 7 performs color conversion of the image input in S201 using the LUT selected in S203. In S205, the image data color-converted in S204 is output from the image output unit 8 and printed by the image output device 9.

<User interface>
In the above embodiment, an example of a UI is shown in FIG. For example, as shown in FIG. 3B, a plurality of stages may be provided between the emphasis on color development and the weather resistance, a plurality of LUTs corresponding to the stages may be prepared, and the LUTs may be switched.

  In other words, any UI configuration that allows the user's desired settings may be used.

  As described above, according to the first embodiment, in a printer capable of printing a high-saturation image using spot color ink, when the weather resistance of the high color spot color ink is poor, the trade-off between weather resistance and color developability is achieved. When the user selects OFF, the effect of the special color ink can be maximized in the color development priority mode, and in the weather resistance priority mode, printing can be performed using only ink having good weather resistance, and high weather resistance can be obtained.

(Second embodiment)
Hereinafter, a second embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 4 is a block diagram showing a configuration of an image processing apparatus according to an embodiment of the present invention. 401 is an image processing apparatus according to an embodiment of the present invention. An image data storage unit 402 stores image information to be output, such as a hard disk or a CD-ROM. Reference numeral 403 denotes an image input unit for reading image data from the image data storage unit 402 into the image processing apparatus 401. A color distribution calculation unit 404 calculates the color distribution of the image input from the image input unit 403. A color gamut comparison unit 405 compares the color distribution calculated by the color distribution calculation unit 404 with the color gamut of the printer. Reference numeral 406 denotes an LUT selection unit for selecting an LUT used for color conversion based on the result of comparison by the color gamut comparison unit 405. An LUT storage unit 407 stores an LUT used for color conversion. A color conversion unit 408 performs color conversion processing on the image input by the image input unit 403 using the LUT stored in the LUT storage unit 407. An image output unit 409 outputs the image data converted by the color conversion unit 408. Reference numeral 410 denotes an image output device such as an ink jet printer that actually performs printing based on the image data output from the image output unit 409.

<Overall processing>
Here, FIG. 5 is a flowchart of image processing performed by the image processing apparatus 401. Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings. First, in S501, the image input unit 403 reads image data from the image data storage unit 402 into the image processing apparatus 401. In step S502, the color distribution calculation unit 404 calculates the color distribution of the image input from the image input unit 403. In S503, the color gamut comparison unit 405 compares the color distribution calculated by the color distribution calculation unit 404 with the color gamut when the special color ink stored in the LUT storage unit 407 is used and when not used. . In S504, based on the result of comparing the color gamut in S503 in the LUT selection unit 406, a lot of special color inks are used from among the LUTs stored in the LUT storage unit 407, and the LUT that emphasizes color development or the special color inks The color conversion LUT is selected from the LUTs that emphasize the weather resistance. In S505, the color conversion unit 408 performs color conversion of the image input in S501 using the LUT selected in S504. In S506, the image data color-converted in S505 is output from the image output unit 409 and printed by the image output device 410.

<Color gamut comparison>
Here, the color gamut comparison method performed in S503 will be described in detail.

  As shown in FIG. 6, each color of the input image is within the color gamut when the special color ink is used (color gamut A) and when not used (color gamut B). Judge whether it is in.

  In the above determination, for colors that are in the color gamut A and outside the color gamut B (colors indicated by black circles in FIG. 6), the use of the special color ink produces a more effective output result. can get. Therefore, the ratio of pixels having a color that is in the color gamut A and outside the color gamut B to all pixels in the input image is calculated, and the ratio is larger than a preset threshold value. For example, in order to realize color gamut A, an LUT using a special color ink is used. On the contrary, if the above ratio is smaller than the threshold value, an image is output using an LUT that does not use the special color ink in order to improve the weather resistance. I do.

<Color space>
In Example S503, the color gamut comparison is performed in the Lab space, but it is needless to say that the present invention is not limited to this. For example, a color space such as a Luv space, an XYZ space, or the like that shows how the color threshold changes depending on whether or not the special color ink is used and how the color reproduction in the input image changes. If is used, the type is not limited.

  As described above, according to the second embodiment, in a printer capable of printing a high-saturation image using spot color ink, when the weather resistance of the high color spot color ink is poor, the trade-off between weather resistance and color developability is achieved. By selecting OFF according to the content of the input image, an image that contains many colors that cannot be reproduced without using special color ink can be used to maximize the effect of special color ink, and on the contrary, can be expressed without using special color ink. An image containing many colors that can be printed with only ink having good weather resistance can provide high weather resistance.

(Other examples)
Note that the present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, and a printer), and a device (for example, a copying machine and a facsimile device) including a single device. You may apply to.

  Another object of the present invention is to supply a storage medium storing software program codes for realizing the functions of the above-described embodiments to a system or apparatus, and the computer (or CPU or MPU) of the system or apparatus stores the storage medium. Needless to say, this can also be achieved by reading and executing the program code stored in.

  In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention.

  As a storage medium for supplying the program code, for example, a floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, magnetic tape, nonvolatile memory card, ROM or the like is used. I can do it.

  In addition, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) running on the computer based on the instruction of the program code. It goes without saying that a part of the actual processing is performed and the functions of the above-described embodiments are realized by the processing.

  Further, after the program code read from the storage medium is written to a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. It goes without saying that the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

1 is a block diagram illustrating an image processing apparatus according to a first embodiment. 5 is a flowchart for explaining a processing flow in the image processing apparatus according to the first embodiment. An example of the user interface for print quality setting of a 1st Example. The block diagram which shows the image processing apparatus of a 2nd Example. 9 is a flowchart for explaining a processing flow in the image processing apparatus according to the second embodiment. An example of a color gamut with and without special color ink and a color distribution of an input image.

Claims (7)

  An image input means for inputting an image, a print quality setting means for determining whether weather resistance or color development should be emphasized in the output image, and an LUT selection means for selecting an LUT based on a set value by the print quality setting means A color conversion unit that converts the color of the input image using the LUT selected by the LUT selection unit; and an image output unit that outputs the image color-converted by the color conversion unit. Image processing device.   2. The image according to claim 1, wherein the print quality setting unit selects an LUT to be used when the user selects emphasis on color development or emphasis on weather resistance on the user interface for the input image. Processing equipment.   The print quality setting means compares the color gamut of the case where the special color ink is used with the case where the special color ink is not used for the input image, determines whether the special color ink needs to be used, and selects the LUT to be used. The image processing apparatus according to claim 1.   The said LUT selection means selects any one from two types of LUT of LUT which uses special color ink to the maximum, and LUT which does not use special color ink at all. Image processing device.   The LUT selection means includes a plurality of LUTs in which the amount of spot color ink used is changed stepwise in addition to two types of LUTs: a LUT that uses spot color ink to the maximum and a LUT that does not use spot color ink at all. The image processing apparatus according to claim 1, wherein any one of the types is selected.   An image input step for inputting an image, a print quality setting step for determining whether weather resistance or color development is to be emphasized in the output image, and a selection step for selecting a color conversion condition based on a set value in the print quality setting step And a color conversion step of converting the color of the input image using the selected color conversion condition.   The image processing method according to claim 6, wherein the print quality setting step sets emphasis on color development or emphasis on weather resistance on a user interface in accordance with a user instruction.

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