JP2001186369A - Picture output device and picture output method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily change a color tone without returning to a previous process in a process for making a machine plate in a digitized printing process using a CTP device. SOLUTION: Plural gradation conversion curves which are preserved in a gradation conversion curve preservation part 22 and whose gradation characteristics stepwise differ are displayed on a display 36. A keyboard mouse 34 selects the desired gradation conversion curve in the plural gradation conversion curves on at least one color element in CMYK. The selected gradation conversion curve is set in an LUT conversion aprt 26. Thus, input picture data G can easily converted into output picture data Ga which is gradation-converted by the gradation conversion curve that is set in the LUT conversion part 26. Thus, picture data Ga is set to be binary picture data H by a thresholding part 30 and is supplied to a CTP device 14 which is integrally constituted. The machine plate having a binary picture corresponding to binary picture data H is outputted from the CTP device 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CTP (comput
er to plate) equipment and CTC (computer to cylinder)
Used in the device, for example, 0, 1, 2, ...,
The present invention relates to an image output apparatus and method suitable for use in a raster image processor for converting digital image data having a value of 255 into digital image data such as binary or quaternary data for scanning and recording.

[0002]

2. Description of the Related Art Conventionally, in the field of printing plate making, a printing plate to be mounted on a printing press has been prepared using a contact printer. However, in recent years, digitization including plate making is progressing.

In the field of printing plate making, it is necessary that the color of a printed sample matches the color (color) of a printed matter printed by a printing machine.

[0004] In a conventional process in the order of a plate making process, a film making process, a plate making process, and a printed matter created by a printing machine, the colors of the printed matter created by the printing machine do not match the colors of the printed sample. If there is a defect of the printing operator, the printing operator first,
C (cyan) version, M (magenta) version, Y (yellow) version, K
(Sumi) Attempt to adjust by adjusting the amount of ink for each plate.

[0005] If this cannot be done, the process returns to the printing plate preparation process, which is the upstream process of the printing press, and the printing plate is prepared again to adjust the color. That is, in a contact printer, a film is brought into close contact with a plate material and exposed with ultraviolet rays. In the so-called contact exposure, the exposure time is adjusted to adjust the exposure time for each separation (C plate, M plate, Y plate, and K plate). The degree of printing (also called the printing amount) is changed to change the gradation, and the color of the entire printed matter is adjusted. In this case, the adjustment of the exposure time is conventionally performed by the printing amount (light intensity × time).
(3 steps, 5 steps, 6 steps, etc.).

On the other hand, in a new process using a CTP device to which a raster image processor (hereinafter, also referred to as RIP) is attached recently, for example, values of 0, 1, 2,. Is supplied to a CTP device, and a printed plate can be obtained directly from the CTP device.

[0007]

However, in the RIP attached to the current CTP device, the gradation characteristics of the entire plate are easily changed by changing the printing amount as in the conventional case. There is a complication that there is no means and it is necessary to return to the step of creating the digital image data in order to change the entire gradation.

In addition, usually, an operator in the process of using a CTP device is often unfamiliar with the creation of digital image data on a workstation or the like where the process of creating image data is performed. There is a problem that it takes time.

[0009] Also, with the development of network technology, CT
In many cases, the location where the P device or CTC device is installed is physically separated from the location where the digital image data is created. When changing the overall gradation, the digital image data is corrected by going back to the digital image data creation process There is also a problem that it is difficult to do.

A technique has been proposed for performing this gradation correction for the purpose of mainly correcting the dot gain during printing in the RIP. In this technology, all gradations are set to 10
A printed matter having patches divided into stages is output as a test chart, and dot gain correction is performed by inputting a dot% read value of each patch on the test chart to the RIP, which is quite complicated. It takes time. Therefore, with this technique, it is possible to take time to adjust the time of installation of the CTP device or the like, but there is a problem that it is not possible to easily correct the color of the picture in daily work.

The present invention has been made in consideration of the above problems, and has been developed in a digitizing printing process using a CTP device, a CTC device, or the like, in a process of preparing a printing plate or the like, in a preceding process. It is an object of the present invention to provide an image output apparatus and a method thereof that enable simple color correction of a picture without returning, in other words, tone correction of each color separation.

[0012]

SUMMARY OF THE INVENTION The present invention provides an image output for producing at least one of a printed matter, a printed matter proofreading sample, a printing plate, and a printing plate making film directly from image data containing one or more color elements. An apparatus for preparing a plurality of gradation conversion curves having gradation characteristics that are different in a stepwise manner; and for at least one of the color elements, a desired gradation conversion from the plurality of gradation conversion curves. Selecting means for selecting a curve, the image data is supplied,
And a gradation conversion unit that outputs image data whose gradation is converted by the selected desired gradation conversion curve (the invention according to claim 1).

According to the present invention, the preparation means prepares a plurality of gradation conversion curves whose gradation characteristics differ stepwise. Then, for the image data including at least one color element, a desired gradation conversion curve is selected from the plurality of gradation conversion curves by the selection means and set in the gradation conversion means. As a result, it is possible to easily obtain output image data in which image data including at least one color element is subjected to gradation conversion by gradation conversion means in which a desired gradation conversion curve is set.

In this case, a desired gradation conversion curve can be immediately selected by using a storage means for storing a plurality of gradation conversion curves whose gradation characteristics differ stepwise as a preparation means. It can be obtained quickly (the invention of claim 2).

Further, by using a preparation means for preparing a plurality of gradation conversion curves having gradation characteristics that are different stepwise as preparation means, output image data is obtained using an arbitrary and desired gradation conversion curve. (The invention according to claim 3).

In this case, by making each of the plurality of gradation conversion curves have a gradation change amount corresponding to the printing amount in the printing plate printing process of the contact exposure, the conventional conversion process can be used. An operator or the like can perform gradation conversion without any discomfort in operability in terms of operability, and thus can perform visibility conversion with good visibility (the invention according to claim 4).

Specifically, each of the plurality of gradation conversion curves having a gradation change amount corresponding to the printing amount is given a name corresponding to the printing amount. This makes it possible to uniquely select a gradation conversion curve corresponding to a desired printing amount (the invention according to claim 5).

A plurality of gradation conversion curves having gradation characteristics that differ stepwise are provided only by the highlight of the gradation conversion curve, only by the middle tone of the gradation conversion curve, or only by the shadow of the gradation conversion curve. By using a plurality of gradation conversion curves having gradation characteristics that differ stepwise, not only adjustment of the entire gradation, but also gradation adjustment in a desired region of highlight, middle tone, or shadow can be performed ( The invention according to claim 6).

Furthermore, a desired tone conversion curve can be easily obtained by providing a tone conversion curve creating / correcting means for newly creating or correcting the tone conversion curve (the invention according to claim 7). ).

By simultaneously displaying a plurality of gradation conversion curves on the display means, it is possible to easily select a desired gradation conversion curve visually.
Described invention).

According to the present invention, there is provided an image output method for producing at least one of a printed matter, a printed matter proofreading sample, a printing plate, and a printing plate making film directly from image data including one or more color elements. A preparation process of preparing a plurality of gradation conversion curves having stepwise different tonal characteristics; and selecting a desired gradation conversion curve from the plurality of gradation conversion curves for at least one of the color elements. 10. The method according to claim 9, further comprising a selecting step and a gradation converting step of outputting the image data to which the image data is supplied and subjected to gradation conversion by the selected desired gradation conversion curve. .

According to the present invention, in the preparation process, a plurality of gradation conversion curves having gradation characteristics that differ stepwise are prepared. Then, in the selecting step, the image data including at least one color element is selected from among the plurality of gradation conversion curves.
Select a desired gradation conversion curve. Next, in a gradation conversion process, image data including at least one color element is
Output image data obtained by performing gradation conversion with a desired gradation conversion curve is obtained. Thus, desired output image data can be easily obtained.

In this case, the preparatory process is a storing process of storing a plurality of gradation conversion curves having gradation characteristics that differ stepwise, so that a desired gradation conversion curve can be immediately selected. It can be obtained quickly (the invention according to claim 10).

Further, the preparation process is a process of preparing a plurality of gradation conversion curves having gradation characteristics that differ stepwise, so that output image data is obtained using an arbitrary and desired gradation conversion curve. (Invention of claim 11).

[0025]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a basic configuration of an image output apparatus 10 according to an embodiment of the present invention.

This image output device 10 is supplied with a commercial
A gradation conversion / binarization processing device including a raster image processor (RIP) for performing gradation conversion processing on YK digital image data G as necessary and converting the image data into binary image data H for each CMYK plate 12, and a printing plate PP for each of CMYK plates based on the binary image data H connected thereto.
And a CTP device 14 that outputs the same.

Even when digital image data G of one color element among the CMYK color elements is supplied, the image output device 10 outputs the binary image data H corresponding to the digital image data G of the one color element. Is output.

Here, the CMYK digital image data G
Are created by an editing workstation or the like (not shown), for example, 0, 1, 2,... 25, respectively.
5 is digital image data G of each of CMYK planes having a value of 5.

The image output device 10 is basically constituted by a computer and is a device capable of directly producing a printing plate PP from digital image data G. As an image output device, such a CMYK digital 1 is not limited to the image output device 10 of FIG. 1 that directly creates the printing plate PP from the image data G, or a CTC device that directly creates a printed matter from digital image data including one or more color elements, or a printed matter directly. DDCP for creating a calibration sample
(Direct digital color proof) device or directly,
A film setter or the like for producing a printing plate making film can be used.

The CTP device 14 shown in FIG. 1 is a device which scans and records a plate material by a laser beam which is turned on and off by binary image data H, which is scanned image data, and outputs a plate PP.

FIG. 2 shows a detailed configuration example of the gradation conversion / binarization processing device 12 in the image output device 10 of FIG.

The gradation conversion / binarization processing device 12 includes a gradation conversion curve storage unit 22 as storage means for storing a plurality of gradation conversion curves having gradation characteristics that differ stepwise as data, and a CMYK storage unit. Selecting means for selecting one desired tone conversion curve from a plurality of tone conversion curves stored in the tone conversion curve storage unit 22 for at least one of the color elements (gradation conversion curve selection) And a gradation conversion curve selection unit 24 that functions as an image display auxiliary unit for displaying an image represented by the image data G, Ga, and H.

The gradation conversion / binarization processing device 12
An LUT (look-up table) conversion unit 26 as a gradation conversion unit for setting the selected one desired gradation conversion curve is provided. The LUT conversion unit 26 converts the supplied digital image data G And outputs the digital image data Ga whose gradation has been converted by the selected one desired gradation conversion curve.

Further, the gradation conversion / binarization processing device 12
Are digital image data Ga subjected to gradation conversion by the LUT conversion unit 26 and threshold data (threshold matrix) T (T = 1, 2,..., 255) read from the threshold storage unit 28
When Ga <T, the value 0 (non-blackening), Ga ≧ T
A binarizing unit 30 that outputs binary image data H having a value of 1 (blackening) at the time.

As the threshold data T, the user:
The gradation conversion curve selecting means 24 can select the threshold data T whose number of lines, halftone angle and the like are desired.

An image corresponding to the binary image data H output from the binarizing section 30, for example, a printing plate PP on which a halftone image is formed is output from the CTP device 14.

The gradation conversion curve selection means 24 is a GU
A processing / judgment unit 32 having a built-in I (graphical user interface);
A display device having a function of simultaneously displaying a plurality of gradation conversion curves stored in the gradation conversion curve storage section 22 while being connected to a keyboard / mouse @ keyboard and / or mouse # 34 as input means. Display 36 is connected.

An image corresponding to the digital image data G and Ga and an image corresponding to the binary image data H can be displayed on the display 36 through the processing / judgment unit 32.

The image output device 10 according to this embodiment
Is basically constructed as described above.
Next, the operation will be described.

When the power of the image output apparatus 10 is turned on and the gradation conversion processing is set by the keyboard / mouse 34, the processing / judgment unit 32 determines the plurality of floors stored in the gradation conversion curve storage unit 22. Display 3 tonal conversion curve
6 are displayed simultaneously.

FIG. 3 shows an initial state of the display screen 50 displayed on the display 36. This screen 50
A display unit (gradation conversion curve display unit) 52 for displaying a plurality of gradation conversion curves and a setting display unit (gradation conversion curve setting display unit) 54 for the selected gradation conversion curve are provided.

In the gradation conversion curve display section 52, the gradation characteristics are changed from "-3" to "-2", "-1", "0", "+".
Seven stepwise different gradation conversion curves labeled “1”, “+2”, and “+3” are displayed. Each of the gradation conversion curves is a curve for converting the value (input value) of the input image data G into the value (output value) of the output image data Ga by the LUT conversion unit 26.

For each gradation conversion curve, the input value is x and the output value is
Is represented as y, for example, by a function of y = x + f (x).
Then, the function f (x) of each gradation conversion curve is f (x) =
ax ^Four+ Bx^Three+ Cx quadratic function.
Wear.

The full scale of the input image data G and the output image data Ga of the gradation conversion curve display section 52 shown in FIG. 3 ranges from a value of 0 (corresponding to G = Ga = 0) to 1 (G = Ga = 25).
5) or a halftone value from 0% (equivalent to G = Ga = 0) to 100% (equivalent to G = Ga = 255). It is also possible to display with gradation values of 0 to 255.

On the other hand, in the gradation conversion curve setting display section 54 shown in FIG. 3, the color elements "Y", "M", "C", "K" are displayed.
Are displayed, and the color elements “Y”,
The number (-3, -2,-) of the name of the gradation characteristic of the gradation conversion curve selected for each of "M", "C", and "K"
A gradation conversion curve setting box 61 for displaying any one of the numbers 1, 0, +1, +2, +3).
64 is displayed. In the example of FIG. 3, “0” is displayed in each of the gradation conversion curve setting boxes 61, 62, 63, and 64.

The gradation conversion curve setting boxes 61 to 6
In order to change the value of 4, the gradation conversion curve setting display 5
By moving the mouse pointer MP to desired gradation conversion curve setting boxes 61 to 64 related to the color elements “Y”, “M”, “C”, and “K” in 4 and clicking the mouse 34, It becomes a screen where you can enter numbers, "-3",
"-2", "-1", "0", "+1", "+2",
By placing the mouse pointer MP on a desired gradation conversion curve and clicking on the gradation characteristics up to “+3”, the selected numeral corresponding to the gradation conversion curve is changed to a desired gradation conversion curve setting box 61 to 61. 64 is set.

FIG. 4 shows a keyboard / mouse 34
As the gradation conversion curve of magenta M, the number “+” of the gradation characteristic
2 shows a display screen 50a as an example in which “2” is selected and set. By making such settings on the display screen 50a of the display 36 and pressing an execution key (not shown), the gradation conversion curve (C = “0”, M =
Lookup tables corresponding to “+2”, Y = “0”, K “0”) are sequentially read from the gradation conversion curve storage unit 22 and set in the LUT conversion unit 26.

The LUT conversion section 26 converts the supplied CMYK image data (input value) G into gradations by sequentially setting gradation conversion curves, and converts the CMYK image data after gradation conversion.
The image data (output value) Ga is output. That is, the C image data Ga is converted by a gradation conversion curve (C = “0”), and the M image data Ga is converted by a gradation conversion curve (M = “+”).
2)), the Y image data Ga is converted by a gradation conversion curve (Y = “0”), and the K image data Ga is converted by a gradation conversion curve (K = “0”).

The CMYK image data Ga after the gradation conversion is sequentially supplied to the binarizing section 30, and the halftone image data as the binary image data H is output to the CTP device 14.

Using the binary image data H, the CTP device 1
According to the printing plate PP of each of the CMYK plates output from No. 4, the magenta M corresponding to the gradation characteristic "+2"
The volume of the plate can be increased, in other words, the magenta M plate can be a plate with more ink.

As described above, according to the above-described embodiment,
In the digitized printing process using the CTP device 14 (or the CTC device or the like), the image output device 10 in the process of creating the printing plate PP or the like simply displays on the display 36 without returning to the previous process. Only by performing the operation of selecting the converted gradation conversion curve, it is possible to obtain the advantage that the color tone of the picture can be simply corrected, in other words, the gradation correction of each separation can be performed.

The gradation correction by the image output device 10 is as follows.
Since the printing plate PP is re-created, color adjustment that cannot be completely adjusted by adjusting the amount of ink in the printing process can be easily performed using the GUI.

The correction by the image output device 10 is performed when the printing machine is different, when the plate material is different, and when the ink and the paper (paper used for final printing) are different, or the lot of the plate material, the ink, and the real paper is used. It is possible to easily and flexibly perform a process for adjusting a color to a print sample even in a printing process in which various conditions are different, such as a variation in the printing process.

The gradation conversion / binarization processing device 12 shown in FIG. 2 is the same as the gradation conversion / binarization processing device 12A shown in FIG.
Can be changed to In the gradation conversion / binarization processing device 12A of FIG. 5, the components corresponding to those shown in the gradation conversion / binarization processing device 12 of FIG. Description is omitted.

The gradation conversion / binarization processing device 1 shown in FIG.
2A, the gradation conversion / binarization processing device 1 shown in FIG.
2, the LUT conversion unit 26 is omitted and the binarization unit 30
Between threshold value storage unit 22 and threshold value storage unit 28A
Is provided.

That is, in the gradation conversion / binarization processing apparatus 12A of FIG. 5, the gradation conversion curve selected by the gradation conversion curve selection means 24 is incorporated in the threshold data T in the threshold storage unit 28A. I have to. In this way, the binarizing unit 30 includes a gradation conversion process when generating the binary image data H from the digital image data G.
Value processing can be performed.

Here, the processing for incorporating the gradation conversion curve into the threshold data T is performed, for example, as described in Japanese Patent Application Laid-Open No. 8-98025, for example, with the gradation characteristic "+2" (see FIG. 3). When the conversion curve is selected, the gradation characteristic of the gradation conversion curve is a characteristic that converts the input image data G = 127, for example, the gradation characteristic = “+ 2” to a value larger by 20%. Assume that

That is, the image data G = 127 is converted into image data G = 152 (≒ 127 × 1.2).
Out of all the threshold data T from 1 to 255 stored in A, the threshold data T = T (1, 2, 2,
, 152) to threshold data T = T (1, 2,..., 127) up to the threshold data T = 127. When the conversion is performed in this manner, for example, the input image data G having the halftone% of 50% is converted to the halftone% of 60%
Will be converted into binary image data H.

The gradation conversion / binarization processing apparatus 1 shown in FIG.
The image output device 10 having 2A is the image conversion device of FIG.
An effect similar to that of the image output device 10 having the binarization processing device 12 is achieved.

FIG. 6 shows a display screen 50b of another display example on the display 36. This display screen 50b
Each of the plurality of gradation conversion curves of the upper gradation conversion curve display section 52b indicates an output value halftone value with respect to an input value halftone value, and a gradation change corresponding to a printing amount in a printing plate printing process of contact exposure. Is to have an amount.

More specifically, a plurality of gradation conversion curves having a gradation change amount corresponding to the printing amount are respectively named “3-stage white missing” and “5-stage white missing” corresponding to the respective printing amounts. , "7-step white drop", and "8-step white drop".

Normally, the exposure amount for printing on a printing plate is controlled by applying a density patch on the printing plate and determining the number of levels of whitening and the number of levels from which an image is formed. here,
The density patch is, for example, a patch divided into about 15 steps from highlight HL to shadow SD for each density difference of 0.15. “Three-step white drop” refers to the density patch 3
The exposure amount at which the density portion of the lower stage is white and the image is black in the fourth and subsequent stages. Note that, here, a positive type printing plate is shown, and a portion where the proper exposure amount is reached is lost in white. Similarly, the “fifth-step white drop” means an exposure amount in which the density portion of the fifth step of the density patch is white and the image is black in the sixth and subsequent steps. The exposure amount is twice as large. Hereinafter, “7-step white dropout” and “8-step white drop-out” refer to the exposure amount in a state where the number of steps is white, and in the case of a positive type printing plate, the larger the number of steps, the more the exposure amount is given. As a result, the blank portion becomes large, and the dot% is on a decreasing trend.

In the example of FIG. 6, the mouse pointer MP is set to the gradation conversion curve of "three-step white dropout" in the gradation conversion curve display section 52b. 54b, the color element “Y”,
In each of the gradation conversion curve setting boxes 61 to 64 of “M”, “C”, and “K”, “3 steps white missing” is displayed.

By making it possible to select a gradation conversion curve on the display screen 50b in the example of FIG. 6, an operator who is accustomed to the conventional contact exposure work can very easily obtain a desired gradation based on his own experience. A conversion curve can be selected.

The gradation conversion curve having gradation characteristics displayed on the gradation conversion curve setting display section 54b of FIG. 6 is stored as data in the gradation conversion curve storage section 22, and is stored in the gradation conversion curve storage section 22. The gradation conversion curve selected by the curve selection means 24 is read from the gradation conversion curve storage unit 22 and set in the LUT conversion unit 26 in the gradation conversion / binarization processing device 12 of FIG. In the gradation conversion / binarization processing apparatus 12A of FIG. 5, the threshold data T of the threshold storage unit 28A is stored.
Is converted.

As described above, by registering the gradation conversion curve as a curve corresponding to the conventional printing amount, an operator who is accustomed to the conventional printing plate process can utilize the image correction know-how of the conventional process to perform CTP. The operation of the image output device 10 in a new process having the device 14 can be easily performed. For this reason, the effect that the recent image output device 10 based on digital data can be smoothly introduced is achieved.

Display screens 50, 50 shown in FIGS. 3, 4, and 6
The gradation conversion process using the gradation conversion curves displayed at a and 50b is a gradation conversion process for converting all gradations from 0% to 100% of the input gradation to output gradations. Things.

The gradation characteristics relating to the gradation conversion curve that can be stored in the gradation conversion curve storage unit 22 are not limited to such gradation conversion for all gradations. As shown, the highlight (HL) portion, the middle tone (M
A gradation conversion curve that can perform gradation conversion independently on the D) portion or the shadow (SD) portion can be stored.

As shown in the example of FIG. 7, "0" and "+1", "+2", "+3", "-1",
It is possible to select seven gradation conversion curves of “−2” and “−3”. In the middle tone portion, it is possible to select five gradation conversion curves "0", "+1", "+3", "-1", and "-3". Further, in the shadow part, “0”, “+1”, “+2”, “−1”, “−”
It is possible to select five gradation conversion curves of “2”.

The display screen 50c in the example of FIG. 7 includes a display section (gradation conversion curve display section) 52c of a plurality of gradation conversion curves for converting the entire gradation (entire gradation), a highlight section,
It has a plurality of gradation conversion curve display sections 52d for each of a middle tone section and a shadow section.

The display screen 50c in the example of FIG. 7 includes a gradation conversion curve setting display section 54c selected from the gradation conversion curve display section 52c for converting the entire gradation and a gradation conversion setting display section. 54c "Y", "M", "C",
Each of the gradation conversion curve setting boxes 61 to 64 of “K” is provided.

Further, the display screen 50c in the example of FIG.
Gradation conversion curve display section (gradation conversion curve display section) 52d
And a partial gradation conversion curve setting display section (partial gradation conversion curve setting display section) 54d selected from.

This partial gradation conversion curve setting display section 54d
Means "HL", "MD", "SD" for Y color (Y version)
Partial gradation conversion curve setting boxes 71, 72, 73
"HL", "MD", "SD" for M colors (M version)
Partial gradation conversion curve setting boxes 81, 82, 83
"HL", "MD", "SD" for C color (C version)
Partial gradation conversion curve setting boxes 91, 92, 93
"HL", "MD", "SD" for K color (K version)
Partial gradation conversion curve setting boxes 101, 102, 1
03.

The gradation conversion curve setting display section 5 of the example shown in FIG.
4c and the display displayed on the partial gradation conversion curve setting display unit 54d, in the whole gradation conversion, the whole gradation conversion is performed so that the volume of the magenta M is “+2”, and the volume of the middle tone part of the Y color is performed. Is set to "-2", the partial gradation conversion is further performed to improve the highlighting of cyan C by "+2", and no gradation conversion is performed for the K color. It is understood that it is.

As described above, the display screen 50c shown in FIG.
According to the gradation conversion / binarization processing devices 12 and 12A having the gradation conversion curve storage unit 22 for storing the gradation conversion curve according to the above, it is possible to independently perform the gradation conversion on the entire gradation. The gradation conversion can be performed independently for the partial gradations of the highlight part, the middle tone part, and the shadow part. Furthermore, gradation conversion can be performed by combining the entire gradation and the partial gradations of the highlight portion, the middle tone portion, and the shadow portion.

Further, as another embodiment, the image data G supplied to the gradation conversion / binarization processing devices 12 and 12A is, for example, image data for one page, and The binary image data H, which has been binarized by the binarization unit 30 corresponding to the image data, is displayed on the display 36 through the processing / judgment unit 32 as shown in FIG.
When 5 is displayed (the registration marks and the rules are omitted because they are complicated), the yellow image 110Y and the magenta image 11 are displayed.
0M, the cyan plate image 110C and the black plate image 110K are defined by the keyboard / mouse 34 and the mouse pointer MP.
It is also possible to set a desired gradation conversion curve according to the user's preference for each region.

Note that the gradation conversion curve selection means 24 outputs the yellow image 110Y and the magenta image 110 shown in FIG.
It also has a function of displaying a color image on the display 36 by superimposing the M, cyan plate image 110C and the black plate image 110K.

Of course, the same gradation conversion curve can be set for the entire image 105 for one page by the keyboard / mouse 34 and the mouse pointer MP. In the example of FIG. 8, the display screen 50c shown in FIG.
By simultaneously displaying the image 105 shown in FIG. 8 (by displaying them simultaneously on the same display screen 50c), it is possible to easily and easily select a gradation conversion curve.

Further, in another embodiment, a plurality of gradation conversion curves stored in the gradation conversion curve storage unit 22 are newly created or corrected by the processing / judgment unit 32 and stored as follows. be able to.

In this sense, the gradation conversion curve selection means 24 shown in FIGS. 2 and 5 can be used as a preparation means for preparing a plurality of gradation conversion curves having gradation characteristics that differ stepwise or as a correction means for correcting. Function.

In this case, it is preferable that the gradation conversion curve storage section 22 be present in relation to the processing speed.
If there is a limitation on memory in hardware, etc., it is not necessarily an essential component.
When necessary, the processing / judgment unit 32 can directly set the gradation conversion curve created / corrected by using an appropriate mathematical formula or the like in the LUT conversion unit 26 or the threshold value storage unit 28A. At this time, the processing / judgment unit 32 (in a broad sense, the gradation conversion curve selection unit 24) is a unit that sets the gradation conversion curve in the LUT conversion unit 26 or the threshold value storage unit 28A. It functions as a preparation unit that prepares a plurality of gradation conversion curves that differ stepwise.

In the gradation conversion / binarization processing unit 12A, the gradation conversion curve created (prepared) by the processing / judgment unit (preparation means) 32 is directly added to the threshold data T in the threshold storage unit 28A. You may include it.

The gradation conversion / binarization processing devices 12, 1
In FIG. 2A, the threshold storage units 28 and 28A may be omitted. In this case, a configuration may be employed in which the processing / judgment unit 32 can create and correct the threshold.

Here, the operation of newly creating or correcting a plurality of gradation conversion curves stored in the gradation conversion curve storage unit 22 by the processing / judgment unit 32 will be described.

A control point / set value display image (control point / set value display table) 121 shown in FIG. 9 is displayed on the display 36 and corresponds to each input value (%) determined in advance by the image output device 10. Control points (%) (in this example, 1,
2, 5, 10, 30, 50, 70, 90, 95, 98,
99), the set value (%) corresponding to each output value (%) (in this example, 1, 3, 8, 15, 40, 70, 80, 9
3, 97, 99, 100) and input with the keyboard / mouse 34.

In the example of FIG. 9, the values of the control point (%) determined in advance are the above-mentioned “1, 2, 2, 4” where the highlight side and the shadow side are finely divided by 10% in the middle tone.
5,10,30,50,70,90,95,98,9
9 ", and the values of the set values (%) inputted and set in correspondence thereto are" 1, 3, 8, 15, 15, 40, 70, 8 ".
0, 93, 97, 99, 100 ".

FIG. 10 shows a control point / set value display image 121.
5 shows an image 122 of the gradation conversion curve creation screen displayed on the display 36 in correspondence with the image. In this embodiment, the set value (%) “1, 3, 8, 15, 40, 70,
80, 93, 97, 99, 100 ”, the tone conversion curve 126 is created (drawn) by the least squares approximation method, but the tone conversion curve 126 is created by the n-th order curve approximation or the spline curve approximation. be able to. In addition,
The gradation conversion curve 124 indicated by a dotted line in FIG.
It is a straight line curve of y = x.

Next, when this gradation conversion curve 126 is used as, for example, a gradation conversion curve with the maximum change amount of halftone%,
Tone conversion curve 1 with minimum change amount of dot% by the same method
28 (see FIG. 11).

Next, the number of gradation conversion curves to be created is set. For example, when the number of generations is set to 4, two gradation conversion curves 130 and 132 which internally divide the generated gradation conversion curve 126 and the gradation conversion curve 128 are generated.

When correcting the gradation conversion curve 126 or the like, the control point / set value display image 121 shown in FIG.
In, the set value given to the required control point may be changed and input.

In this way, in the gradation conversion / binarization processing device 12 (12A), a new gradation conversion curve can be created and corrected. In this way, the created and corrected tone conversion curve can be stored in the tone conversion curve storage unit 22 with an appropriate file name.

When the gradation conversion curve 126 is created and modified using the GUI, an existing gradation conversion curve displayed on the display 36, for example, a linear gradation conversion curve as shown in FIG. With respect to 140, a desired point is held by the mouse / mouse MP with the keyboard / mouse 34, and the held point is held at a desired gradation conversion position (sign “x”).
(Position shown by).

At this time, as shown in FIG. 13, the gradation conversion curve 142 is automatically generated by the processing / judgment section 32 as a curve passing through the point moved by the keyboard / mouse 34.

Hereinafter, similarly to the above-described method of creating the gradation conversion curve described with reference to FIG. 11, the gradation conversion curve 142 thus created is converted into, for example, the gradation conversion with the maximum change amount of the dot%. When forming a curve, a tone conversion curve with a minimum change amount of halftone% is created by the same method.

Next, the number of gradation conversion curves to be created is set, and two new gradation conversion curves for internally dividing the created gradation conversion curves and the gradation conversion curves are created. In this way, a desired gradation conversion curve can be created or corrected.

As described above, according to the above-described embodiment,
When the printing plate PP is created from the CMYK image data G by the image output device 10, as shown in the processing procedure of FIG. 14, in the preparation process of step S1, a plurality of gradation conversion curves having gradation characteristics that differ stepwise are prepared. Prepare and display 36
Display above. As described above, the gradation conversion curve may be prepared in advance and stored in the gradation conversion curve storage unit 22, or may be newly generated by the processing / judgment unit 32. .

Next, in the selection process of step S2, a desired gradation conversion curve is selected from a plurality of gradation conversion curves on the display 36 by the keyboard / mouse 34, and the LUT conversion unit 26 or the threshold storage is performed. Set in section 28A.

Next, in the gradation conversion / binarization process of step 3, the LUT conversion unit 26 performs the gradation conversion process on the CMYK image data G, and then the binarization unit 30 performs the binarization. Whether the processing is performed (FIG. 2 example) or the CMYK image data G is
A binarization process is performed (FIG. 5 example).

Finally, in the output process of step S4, the two-dimensional image created by the gradation conversion / binarization process of step S3 is used.
A printing plate PP is created from the value image data H by the CTP device 14.

In this way, in the image output device 10, in the process of preparing the printing plate PP, the color tone of the pattern is simply corrected without returning to the previous process, in other words, the gradation of each separation. Corrections can be made.

The present invention is not limited to the above-described embodiment, but can adopt various configurations without departing from the gist of the present invention.

[0103]

As described above, according to the present invention, color adjustment that cannot be absorbed by adjusting the amount of ink or the like in the printing process can be directly performed from digital image data including one or more color elements. This can be easily performed in an image output device capable of producing at least one of a printed matter, a printed matter calibration sample, a printing plate, and a printing plate making film.

In addition, the color is adjusted to the printing sample even in a printing process in which various conditions are different, such as different printing presses, different plate materials, different inks, different papers, and different lots. Can be easily and flexibly dealt with.

Furthermore, it is difficult to adjust the printing amount in the conventional contact exposure, and the gradation is limited to only a partial density region (any region of highlight, middle tone, shadow, or a combination thereof). Modifications can be easily implemented.

Since each of the plurality of gradation conversion curves has a gradation change amount corresponding to the printing amount in the conventional printing plate printing process of close contact exposure, the operator in the conventional printing plate process requires the conventional printing plate printing process. By utilizing the know-how of image correction in, a process operation using a new CTP device or the like can be performed. That is, in a recent printing process based on digital image data, a derivative effect that a machine such as a plate setter can be smoothly introduced is also achieved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing an example of a gradation conversion / binarization processing device in the example of FIG. 1;

FIG. 3 is a diagram showing an example of a display screen on which a gradation conversion curve display section and a gradation conversion curve setting display section are displayed.

FIG. 4 is a diagram showing a display screen for explaining a state in which a desired gradation conversion curve is set.

FIG. 5 is a block diagram showing another example of the gradation conversion / binarization processing device in the example of FIG. 1;

FIG. 6 is a diagram showing another example of a display screen on which a gradation conversion curve display section and a gradation conversion curve setting display section are displayed.

FIG. 7 is a diagram showing still another example of a display screen on which a gradation conversion curve display section and a gradation conversion curve setting display section are displayed.

FIG. 8 is a diagram showing a display example of a binary image.

FIG. 9 is a diagram showing a display example of control point / set value images used for creating and correcting a gradation conversion curve.

FIG. 10 is a diagram which is used for describing generation of a gradation conversion curve passing a set value.

FIG. 11 is a diagram which is used for describing creation of a plurality of gradation conversion curves.

FIG. 12 is a diagram provided for describing another example of creating a gradation conversion curve.

FIG. 13 is a diagram provided for describing another example of creating a gradation conversion curve.

FIG. 14 is a process chart according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Image output device 12, 12A ... Gradation conversion and binarization processing device 14 ... CTP device 22 ... Gradation conversion curve storage part 24 ... Gradation conversion curve selection means 26 ... LUT conversion part 28, 28A ... Threshold value storage part 30 binarization unit 32 processing / judgment unit 34 keyboard
Mouse 36 ... Display 50, 50a-50
c: display screen 52, 52b to 52d: gradation conversion curve display unit 54, 54b to 54d: gradation conversion curve setting display unit 61 to 64: gradation conversion curve setting box 103: partial gradation conversion curve setting box 105 Image of one page 110Y: Yellow image 110M: Magenta image 110C: Cyan image 110K: Black image 121: Control point / set value display image 122: Image of gradation conversion curve creation screen 124, 126, 128, 130, 132, 140, 1
42: gradation conversion curve G, Ga, H: image data MP: mouse pointer PP: printing plate T: threshold data

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03F 1/00 H04N 1/40 D 3/10 B41J 3/00 A G06T 5/00 100 B H04N 1/407 H04N 1/40 101E 1/46 1/46 Z

Claims (11)

[Claims] 1. An image output apparatus for producing at least one of a printed matter, a printed matter proofreading sample, a printing plate, and a printing plate making film directly from image data containing one or a plurality of color elements, wherein a gradation characteristic is stepwise. Preparation means for preparing a plurality of different gradation conversion curves, and at least one of the color elements,
Selecting means for selecting a desired gradation conversion curve from the plurality of gradation conversion curves; and gradation conversion for supplying the image data and outputting image data converted by the selected desired gradation conversion curve. And an image output device. 2. An image output apparatus according to claim 1, wherein said preparation means is storage means for storing a plurality of conversion curves whose gradation characteristics differ stepwise. 3. An image output apparatus according to claim 1, wherein said preparation means is a creation means for creating a plurality of tone conversion curves having different tone characteristics stepwise. . 4. The image output device according to claim 1, wherein each of the plurality of gradation conversion curves has a gradation change corresponding to a printing amount in a printing plate printing step of contact exposure. An image output device characterized in that it has a volume. 5. The image output device according to claim 4, wherein each of the plurality of gradation conversion curves having a gradation change amount corresponding to the printing amount is given a name corresponding to the printing amount. An image output device, comprising: 6. The image output device according to claim 1, wherein the plurality of gradation conversion curves having gradation characteristics that are different in a stepwise manner are obtained only by highlighting the gradation conversion curve. An image output device comprising a plurality of gradation conversion curves having gradation characteristics that are different from each other only in the middle tone of the gradation conversion curve or only in the shadow of the gradation conversion curve. 7. The image output apparatus according to claim 2, further comprising a gradation conversion curve creating / correcting means for newly creating or modifying said gradation conversion curve. 8. The image output device according to claim 1, further comprising a display means for simultaneously displaying said plurality of gradation conversion curves. 9. An image output method for producing at least one of a printed matter, a printed matter proofreading sample, a printing plate, and a printing plate making film directly from image data containing one or more color elements, wherein the gradation characteristic is stepwise. Preparing a plurality of different gradation conversion curves, and at least one of the color elements,
A selection step of selecting a desired gradation conversion curve from the plurality of gradation conversion curves; and a gradation conversion in which the image data is supplied and image data converted by the selected desired gradation conversion curve is output. And an image output method. 10. An image output method according to claim 9, wherein said preparation step is a storage step of storing a plurality of gradation conversion curves in which said gradation characteristics differ stepwise. . 11. An image output method according to claim 9, wherein said preparation step is a step of generating a plurality of gradation conversion curves having gradation characteristics that are different in a stepwise manner.