JP4051557B2 - Photo printing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image exposure apparatus that exposes and forms a color image by irradiating a photographic photosensitive material with light of a plurality of exposure colors, and converts input image data into image data for exposure by the image exposure apparatus. An image processing apparatus, a simulation arithmetic apparatus that simulates an image formed on a photographic photosensitive material based on the input image data, and a monitor that displays a simulated image obtained by the simulation arithmetic apparatus And the image processing apparatus includes a color management system for matching the color of the simulated image displayed on the monitor with the color of the image formed on the photographic light-sensitive material. Relates to the device.
[0002]
[Prior art]
Such a photographic printing apparatus is an apparatus that forms an image on a photographic photosensitive material such as photographic paper based on image data such as image data read from a photographic film and image data captured by a digital camera.
In such a photographic printing apparatus, what kind of image is formed on the photographic photosensitive material by the input image data before actual exposure by the image exposure apparatus based on the input image data. It is common practice to display a monitor by simulating the above.
The operator of the photographic printing apparatus can observe the simulated image displayed on the monitor in this way to confirm whether or not the desired image can be obtained. As a result, the exposure condition by the image exposure apparatus can be corrected.
[0003]
As a premise for effectively operating such an operator's work, the color of the simulated image displayed on the monitor and the color of the image actually formed on the photographic photosensitive material must match as much as possible. .
Thus, in order to match the color of the simulated image on the monitor with the color of the image formed on the photographic light-sensitive material, a so-called color management system is a part of the image processing apparatus. As provided. This color management system may be referred to as a color matching system.
The range of colors that can be expressed on a monitor is different from the range of colors that can be expressed on a photographic photosensitive material, and usually the range of colors that can be expressed on a monitor tends to be narrower.
Therefore, the color management system normally performs processing for transferring colors that cannot be expressed by the monitor in the input image data to a color range that can be expressed by the monitor.
In general, such a color management system often includes a data table prepared by comparing the color on the monitor display with the color on the photographic photosensitive material for the image data of a large number of colors and producing the comparison result. .
[0004]
This color management system, for example, is not used as an absolutely invariant one produced as described above, but is related to individual differences in the equipment of the photographic printing apparatus and the characteristics of the photographic photosensitive material used. One of the correction operations is to input to the color management system what kind of image data corresponds to the color with the highest density among the gray system colors, that is, black. There is an operation to do.
Conventionally, such an operation is performed in a high exposure area including the maximum exposure quantity by exposing the photographic photosensitive material by changing the gradation for each exposure color, and from the resulting image, the gradation that appears to be the blackest. A technique is adopted in which an operator visually determines a value and performs an input operation to the color management system.
[0005]
There is Japanese Patent Application No. 2001-384591 as a technology related to the present application. The black color adjustment of the application mainly relates to final image data and actual image data after completion of the color management system and other image processing. This application is intended to set the black color to be input to the upstream color management system, while it is intended to be applied to a technique for adjusting the direct correspondence relationship with the exposure amount. is there.
Due to the difference in the application location, in the prior application, the maximum exposure amount of each exposure color is absolutely limited to the adjusted black exposure amount. The black tone value is input as black for the entire color space of the color management system, although the exposure amount is controlled so that an appropriate color expression can be obtained for the gray system or a color close to it. Color expression with an exposure amount that exceeds the exposure value of the gradation value is possible, and dynamic color expression can be maintained by effectively utilizing the amount of light that can be emitted for each exposure color.
[0006]
[Problems to be solved by the invention]
As described above, when an operator who is skilled in subtle color determination performs work by inputting a black gradation value based on a result of visual determination by an operator to the color management system, Although the color management system can be adjusted satisfactorily, otherwise, the adjustment results vary among operators, and the print quality becomes unstable.
The present invention has been made in view of such a situation, and an object of the present invention is to accurately set a black tone value to be input to a color management system without depending on the skill level of an operator. In the point.
[0007]
[Means for Solving the Problems]
By providing the structure according to claim 1, an image exposure apparatus that irradiates and forms a color image by irradiating light of a plurality of exposure colors onto a photographic photosensitive material, and the input image data is exposed by the image exposure apparatus. An image processing device for converting the image data to image data, a simulation operation device for simulating an image formed on the photosensitive material based on the input image data, and the simulation operation device A monitor for displaying a simulated image, and color management for matching the color of the simulated image displayed on the monitor with the color of the image formed on the photographic material in the image processing apparatus. In a photographic printing apparatus including the system, the density measuring device for measuring the density of the image formed on the photographic photosensitive material, and black A black balance management means for obtaining a corresponding gradation value and inputting it to the color management system, the black balance management means exposing the image exposure apparatus with image data having a set gradation change pattern, Based on the measurement result of the density measuring device for the image formed on the photographic light-sensitive material by the exposure operation, in each density measurement value of the portion where each exposure color is exposed with the gradation value corresponding to the maximum exposure amount, A gradation that specifies the lowest density value and the exposure color that has the lowest density value among the colors corresponding to the exposure color, and obtains a density value that is the same as or close to the lowest density value in other exposure colors A value is specified, and the gradation value of each specified exposure color is input to the color management system as a gradation value corresponding to black. That.
[0008]
That is, the density of an image formed on a photographic photosensitive material with image data having a set gradation change pattern is measured by a density measuring device, and the measurement result is automatically captured and input to a color management system. The gradation value is automatically set.
The set gradation change pattern includes a gradation value corresponding to the maximum exposure amount for each exposure color, and ideally, it is desirable to develop black color in such an exposure state. There is a variation between the colors corresponding to each exposure color.
Therefore, the exposure color having the lowest density value at the maximum exposure amount is specified, and for that exposure color, the gradation value corresponding to the maximum exposure amount is set to the black gradation value, and the other exposure colors are set. Obtains a gradation value from which the density value equal to or sufficiently close to the lowest density value is obtained from the measured density value of the set gradation change pattern so as to balance the exposure color having the lowest density value.
[0009]
The gradation value obtained in this way is a gray color that balances between the exposure colors, and is the maximum density of the gray color that can be expressed by the photographic printing apparatus. The tone value is input to the color management system.
Therefore, the black tone value to be input to the color management system can be accurately set without depending on the skill level of the operator.
[0010]
The image exposure apparatus includes an exposure head capable of irradiating light in units of pixel dots, and the black balance management means includes at least the set gradation change pattern. In the high exposure amount side portion, the high exposure amount pixel dots of the set gradation and the non-exposure or low exposure amount pixel dots are set adjacent to each other.
[0011]
When an image is exposed and formed on a photographic photosensitive material in units of pixel dots, there is a phenomenon that a color oozes out from a high exposure pixel dot to surrounding pixel dots.
It is difficult for the human eye to identify subtle color changes in high-density areas of pixel dots themselves exposed at high exposure, but there are no or low exposure pixel dots around the high-exposure pixel dots. In this case, the low density portion due to the color bleeding can be clearly identified. When the black gradation value input to the color management system is not appropriate, the color balance in the color bleeding portion is The shift will be noticeable. This is particularly remarkable in the case where character data is included in the input image data.
The fact that the color balance shift is conspicuous in this way means that it is easy to detect the color balance shift from the opposite viewpoint.
Therefore, in the set gradation change pattern, it is not easy to measure the density with high accuracy by setting the pixel dots of the high exposure amount of the set gradation and the pixel dots of the non-exposure or low exposure amount to be adjacent to each other. Even in a high-density gradation portion, it is possible to accurately detect a color balance shift between exposure colors, and it is possible to accurately specify a black gradation value.
[0012]
Further, by providing the configuration according to claim 3, the black balance management means includes a pixel dot having a high exposure amount with a set gradation and a pixel dot having no exposure or a low exposure amount in the set gradation change pattern. Are set so that one or a plurality of pixel dots are alternately arranged vertically and horizontally.
Accordingly, a high exposure amount pixel dot and a non-exposure (or low exposure amount) pixel dot are staggered in units of a block constituted by one pixel dot or a plurality of square pixel dots. .
In this way, by setting the formation pattern of the high-exposure pixel dots and the non-exposure or low-exposure pixel dots, color bleeding from the high-exposure pixel dots to the surroundings can be It is possible to detect with good balance in the direction and the horizontal direction, and it is possible to detect a shift in color balance with higher accuracy.
[0013]
Further, by providing the structure according to the fourth aspect, the exposure head is composed of a laser beam exposure type exposure head.
That is, when the pixel dots having a high exposure amount are formed by a laser beam exposure type exposure head, the color bleeding is remarkable, and when an exposure head of this type is provided, the set gradation is high. It is particularly effective to set an exposure amount of pixel dots and a non-exposure or low exposure amount of pixel dots adjacent to each other.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a photo print apparatus according to the present invention will be described below with reference to the drawings.
The photographic printing apparatus DP exemplified in the present embodiment is known as a so-called digital minilab apparatus, and as shown in the block configuration diagram of FIG. 1, developed photographic film, memory card, MO or CD. An image input device IR for inputting image data for producing a photographic print from -R, etc., and an exposure / development device for exposing the image data input by the image input device IR to photographic paper 2 as a photographic photosensitive material PS It is composed of EP.
[0015]
[Schematic configuration of image input device IR]
As schematically shown in FIG. 1, the image input device IR includes a film scanner 3 for reading frame images of a photographic film, an external input / output device 4 including a memory reader, an MO drive, a CD-R drive, and the like, The main control device 5 is configured by a general-purpose small computer system and controls the film scanner 3 and the external input / output device 4 and performs management of the entire photographic printing device DP. Formed on the photographic paper 2, a monitor 5 a that displays a simulated image simulating a finished print image and various control information, an operator console 5 b for manually setting exposure conditions and inputting control information A light reflection type density measuring device 5c for measuring the density of the image to be displayed is connected.
The concentration measuring device 5c is well known as a so-called densitometer.
[0016]
[Configuration of main controller 5]
As schematically shown in FIG. 1, the main control unit 5 includes a simulation arithmetic unit 51 that simulates an image formed on the photographic paper 2 based on image data input from the film scanner 3, and a film scanner. The image processing apparatus 52 that converts the image data input from 3 into image data (exposure image data) to be exposed by an image exposure apparatus EX described later, and the entire photographic printing apparatus DP including control of these operations And a controller 53 for management.
The controller 53 is connected to the network together with the film scanner 3 and an exposure control device 14 described later, and exchanges various management information with each other.
[0017]
The image processing device 52 includes various image processing functions such as sharpness, and a color management system for matching the color of the simulated image displayed on the monitor 5a with the color of the image actually formed on the photographic paper 2. Is provided.
This color management system has a three-dimensional data table expressed in Lab, and the main function is to monitor colors that cannot be expressed on the monitor 5a among the input red, green and blue image data. It converts into the color which can be expressed by 5a, and outputs as red, green, and blue image data.
[0018]
[Overall configuration of exposure / development apparatus EP]
The exposure / development apparatus EP is an image exposure apparatus EX that exposes and forms a color image by irradiating the photographic paper 2 with light of a plurality of exposure colors (specifically, red, green, and blue light) inside the housing. A development processing apparatus PP that develops the photographic paper 2 exposed by the image exposure apparatus EX, and a photographic paper 2 drawn out from the photographic paper magazine 6 disposed in the housing by a number of conveying rollers 9 and the like. A photographic paper transport system PT that transports the toner to the development processing apparatus PP is provided.
The image exposure apparatus EX includes an exposure head 13 that forms an exposure image on the photographic paper 2 by scanning the photographic paper 2 with a light beam, and an exposure control device 14 that controls the exposure head 13. ing.
[0019]
Although not shown, a sorter is provided outside the casing of the exposure / development apparatus EP to classify the photographic paper 2 that has been developed and dried by the development processing apparatus PP for each order. A conveyor 10 for conveying the photographic paper 2 is provided on the upper surface of the casing.
Further, in the middle of the transport path of the photographic paper transport system PT, a cutter 11 that cuts the long photographic paper 2 drawn out from the photographic paper magazine 6 into a set print size and a plurality of photographic papers 2 transported in a row. A sorting device 12 is provided for sorting to the transport rows.
[0020]
[Configuration of Exposure Head 13]
The exposure head 13 employs a so-called laser beam exposure method in which an image is exposed on the photographic paper 2 using a laser as a light source, and a schematic configuration thereof is shown in a block configuration diagram of FIG.
The exposure head 13 includes a red beam laser light source device 20r, a green beam laser light source device 20g, a blue beam laser light source device 20b, and laser light source devices 20r and 20g. , 20b for modulating the intensity of the emitted light beam (hereinafter abbreviated as “AOM element 21”) and the beam diameter of the light beam LB emitted from each of the laser light source devices 20r, 20g, 20b. A beam expander 22, a cylindrical lens 23, a prism 24 that combines the optical axes of the three red, green, and blue light beams LB into one optical axis, and the light beam LB into the photographic paper 2 In addition to the upper polygon mirror 25 that scans in the main scanning direction and the imaging lens group 26 having an f-θ characteristic and a surface tilt correction function, Aperture 28 for restricting the light incident on the mirror 27 and a prism 24 for bending the optical path of over beam LB is located.
[0021]
[Configuration of Exposure Control Device 14]
As schematically shown in FIG. 6, the exposure control device 14 uses image data input from the main control device 5 in consideration of the exposure characteristics of the exposure head 13 in order to control the exposure head 13 having the above configuration. An image processing circuit 30 that performs a correction operation on the data, an image data memory 31 that stores the image data obtained by the image processing circuit 30 for each color of red, green, and blue, and each color of red, green, and blue The D / A converter 32 that converts the digital image data output from the image data memory 31 into an analog signal and the driver circuit 33 that modulates the high-frequency signal output to the AOM element 21 according to the input analog signal. It has been.
[0022]
[Overview of exposure operation]
Next, operations of the exposure head 13 and the exposure control device 14 having the above-described configuration will be described.
The exposure image data input from the main controller 5 is corrected and calculated by the image processing circuit 30 and converted into image data that provides a good print image when exposed by the exposure head 13, and the image data memory 31. Are written sequentially.
The data once stored in the image data memory 31 is sent to the D / A converter 32 in units of pixels in synchronization with a predetermined clock signal for each pixel data, converted into an analog signal, and then sent to the driver circuit 33. Sent.
[0023]
The driver circuit 33 outputs a control signal having an amplitude corresponding to the input analog signal to the AOM element 21. The AOM element 21 has a diffraction rate corresponding to the amplitude of the input signal from each of the light source devices 20b, 20g, and 20r. The intensity of the incident light beam LB is modulated.
Each light beam LB modulated as described above enters the prism 24 after passing through the beam expander 22 and the like, and the three light beams LB of red, green and blue are combined into one light beam LB. Then, the reflection surface of the polygon mirror 25 is irradiated.
[0024]
The light beam LB reflected by the reflecting surface of the polygon mirror 25 that is rotationally driven by the drive motor 25a is scanned in a plane orthogonal to the rotational axis of the polygon mirror 25, and is transported and moved onto the photographic paper 2. The light is condensed by the imaging lens group 26. The scanning direction of the light beam LB intersects (more specifically, orthogonal) with the conveyance direction of the photographic paper 2, the scanning direction of the light beam LB is the main scanning direction, and the conveyance direction of the photographic paper 2 is the sub-scanning direction. Become. An image to be printed on the photographic paper 2 is formed as a latent image by scanning the light beam LB and transporting the photographic paper 2.
As is clear from the above, the exposure head 13 is configured to irradiate light on the photographic paper 2 in units of pixel dots.
[0025]
[Photo print production operation]
Next, a photographic print production operation by the photographic printing apparatus DP having the above configuration will be schematically described.
When the operator inputs an instruction to make a photographic print for the frame image of the photographic film, the controller 53 of the main controller 5 instructs the film scanner 3 to read the photographic film, and the photographic film is read from the film scanner 3. Are sequentially received, and the image data processed by the image processing device 52 is recorded in a built-in memory.
On the other hand, when the operator inputs an instruction to create a photographic print for image data recorded on a recording medium such as a memory card, MO, or CD-R, the controller 53 inputs the image to the corresponding drive of the external input / output device 4. Data reading is instructed, and image data is sequentially received from the drive and recorded in the memory.
[0026]
Based on the image data input as described above, the controller 53 causes the simulation calculation device 51 to calculate a simulated image that would be obtained when a print was produced using the image data, and the calculation is performed. The result is displayed on the monitor 5a.
The operator observes the simulated image on the monitor 5a, and performs an exposure condition correction input operation from the console 5b if an appropriate image is not obtained.
The image processing device 52 generates exposure image data for each of red, green, and blue under predetermined calculation conditions according to the input image data and the correction input.
[0027]
This exposure image data is sent to the exposure control device 14 of the exposure / development apparatus EP, and a latent image of the print image is formed on the photographic paper 2 as described above.
The photographic paper 2 subjected to the exposure processing by the exposure head 13 is transported to the development processing apparatus PP by the photographic paper transport system PT, and is developed by sequentially passing through the respective development processing tanks. Is further dried and then discharged onto the conveyor 10 and collected for each order by a sorter.
[0028]
[Calibration work of photo printing device DP]
Next, the calibration operation of the photographic printing apparatus DP having the above configuration will be described.
This calibration work is to calibrate the photographic printing device DP so that a photographic print with an appropriate color can be obtained based on the image data input from the film scanner 3 or the like. In addition, it is implemented at an appropriate timing.
The outline of the calibration operation will be described. First, a test print having a set gradation change pattern is prepared, the density of the test print is read by the density measuring device 5c, and the exposure in the image processing circuit 30 is determined from the measurement result. The image management data generation conditions, more specifically, the color balance condition between the exposure colors in the high density region (that is, the condition for favorably developing “black”) is applied to the color management system. input.
In this calibration work stage, it is assumed that the image processing circuit 30 of the image exposure apparatus EX that directly associates the image data with the exposure amount is adjusted appropriately.
[0029]
As shown in FIG. 4, the test print is formed by arranging a total of 13 strip-shaped patterns in the short side direction of each strip, and in order from the bottom, the maximum exposure amount is set for each of red, green and blue. The exposed maximum density pattern 41, the red pattern 42 in which the red exposure amount is reduced by four steps from the maximum density pattern 41, and the green exposure amount from the maximum density pattern 41 by four set amounts. And the blue pattern 44 in which the blue exposure amount is reduced in four steps from the maximum density pattern 41 by a set amount.
[0030]
Each pattern in the 13 stages is not a so-called solid image in which all the pixel dots are exposed with the same exposure amount, but as shown in an enlarged view in FIG. The black dots (schematically indicated by a square A) and the non-exposed pixel dots (schematically indicated by a dashed square B in FIG. 2) form a so-called staggered arrangement, and the blocks constituting the staggered arrangement are four pixels. Consists of dots.
That is, a high exposure pixel dot and an unexposed pixel dot are alternately arranged vertically and horizontally with two pixel dots as a unit, and the high exposure pixel dot and the unexposed pixel dot are adjacent to each other.
[0031]
The calibration operation is executed under the control of the controller 53, and the process will be described based on the flowchart of FIG.
The process shown in FIG. 5 is started when the operator inputs an instruction to start the calibration work from the console 5b.
When the processing is started, image data for producing the test print shown in FIGS. 2 and 4, that is, image data having the set gradation change pattern is sent to the exposure control device 14 via the image processing device 52, The photographic paper 2 is exposed based on the image data (step # 1).
[0032]
When the development process of the photographic paper 2 on which the pattern for the test print is exposed is completed and discharged as the test print, the operator sets the test print in the density measuring device 5c, and indicates that the setting is completed. An instruction is input from the console 5b.
When the main controller 5 detects this instruction input (step # 2), it instructs the concentration measuring device 5c to start measurement (step # 3).
The density measuring device 5 c measures the density measurement values of the patterns 41, 42, 43, 44 while conveying and moving the test print in the longitudinal direction, and transmits the density measurement values to the controller 53.
This light reflection type density measuring device 5c is a general densitometer whose measurement target area is about several mm square, and this measurement target area includes several thousand pixel dots. Accordingly, the measurement target area naturally includes at least the unexposed pixel dots, and simultaneously includes the high exposure pixel dots and the unexposed pixel dots.
[0033]
When the controller 53 receives the measurement data from the density measuring device 5c (step # 4), the controller 53 obtains a value for favorably coloring black by balancing the colors among red, green and blue based on the density measurement data. Obtain (Step # 5).
Hereinafter, a process for achieving this color balance will be briefly described.
In the following description, the image data will be described assuming that each of red, green, and blue is expressed by 256 gradations of 0 to 255, and the gradation value “0” is the maximum exposure amount.
As a specific example, the gradation value of each color is expressed in the form of (red gradation value, green gradation value, blue gradation value), and the maximum density pattern 41 is (0, 0, 0), red. The use pattern 42 is changed by gradation value “3” in the range of (3,0,0) to (12,0,0), and the green pattern 43 is changed from (0,3,0) to (0,12, In the range of 0), the gradation value “3” is changed, and the blue pattern 44 is changed in the range of (0, 0, 3) to (0, 0, 12) by the gradation value “3”. A case where a test print is produced will be described.
[0034]
Based on the measurement data input from the concentration measuring device 5c, the relationship as shown in FIG. 3 is obtained.
In FIG. 3, the vertical axis represents the output value of the density measuring device 5c, and the horizontal axis represents the gradation value.
Decreasing the red exposure reduces cyan color on the photographic paper, decreasing the green exposure reduces magenta color on the photographic paper, and decreasing the blue exposure reduces the yellow color on the photographic paper. Therefore, the vertical axis of FIG. 3 displays the measured cyan density value (shown as “C density value” in FIG. 3) with respect to the change in the red exposure amount (tone value), and the green color A measured value of magenta density (shown as “M density value” in FIG. 3) is displayed with respect to a change in exposure amount (tone value), and a yellow value is displayed with respect to a change in blue exposure amount (tone value). The measured density value (shown as “Y density value” in FIG. 3) is displayed.
[0035]
The density measuring device 5c usually cannot obtain an accurate measurement value in an area where the density value exceeds “2.2”, and in the solid image in which all pixel dots are exposed with the same exposure amount, in the high density area, In some cases, there is no clear correspondence between the gradation value and the density measurement value.
On the other hand, when a test print having the above-described pattern is produced and density measurement is performed, as is clear from the measurement example of FIG. The value is sufficiently smaller than “2.2”, and the density measurement value greatly changes following the change in gradation for any of the exposure colors.
That is, it is possible to obtain a measured value that accurately corresponds to the density of the high exposure pixel dots.
This is because the color oozes from a high exposure pixel dot (black square A) to a non-exposed pixel dot (dashed square B) to a position schematically illustrated by a one-dot chain line C. It is estimated that the density value of the exuded part corresponds to the exposure amount of the high exposure pixel dot.
[0036]
When the measurement data as shown in FIG. 3 is obtained, the main control unit 5 exposes all exposure colors with gradation values corresponding to the maximum exposure amount, that is, gradation values (0, 0, 0) (maximum). In the density measurement value in the density pattern 41), the lowest density value and the exposure color among the color development corresponding to each exposure color are specified. In the measurement example of FIG. 3, the density value is “1.32” and the exposure color is red.
Next, a gradation value that can obtain a density value that is the same as or close to the lowest density value (“1.32”) in other exposure colors is specified. In the measurement example of FIG. 3, the gradation value is “12” for the green exposure color and the gradation value “9” for the blue exposure color. Therefore, in this measurement example, when a gradation value (0, 12, 9) is input to the color management system, a proper black color is generated.
[0037]
When the black tone value is normally obtained in this way (step # 6), the black tone value, that is, the tone value on the highest density side of the achromatic color is used as the color management of the image processing device 52. Set in the system (step # 7).
As a result, the color management system corrects the achromatic color reproduction condition used for the calculation of the image data for exposure.
On the other hand, in the density measurement result as illustrated in FIG. 3, when a value close to the minimum density is not found in the measured density data of the exposure color other than the exposure color at which the density value at the maximum exposure amount becomes the minimum density, Alternatively, when the difference between the gradation values is too large between the exposure colors even if the close value is found, it is determined that the black balance value is not normal (step # 6), and that fact is displayed on the monitor 5a. (Step # 8) is completed.
Therefore, the controller 53 functions as black balance management means BB that obtains a gradation value corresponding to black and inputs it to the color management system.
[0038]
[Another embodiment]
Hereinafter, other embodiments of the present invention will be listed.
(1) In the above embodiment, the case where the test print is produced by changing the exposure amount of each color in a total of 13 stages is exemplified. However, the stage may be set more finely, and the arrangement state of each pattern Can be changed as appropriate.
(2) In the above-described embodiment, a staggered arrangement is formed by alternately arranging two pixel dots as one unit vertically and horizontally. However, one pixel dot or three or more pixel dots are regarded as one unit. A staggered arrangement may be formed by alternately arranging vertically and horizontally.
[0039]
(3) In the above-described embodiment, the high exposure amount pixel dot and the non-exposure pixel dot are adjacent to each other. However, in the range in which the color bleeding from the high exposure amount pixel dot can be accurately detected, The non-exposed pixel dots in the embodiment may be replaced with low exposure pixel dots.
(4) In the above embodiment, the high exposure pixel dots and the non-exposure pixel dots are arranged adjacent to each other. However, if the density measuring device 5c capable of measuring a high density image with sufficient accuracy is used. Alternatively, a test print may be produced by the solid image in which all pixel dots are exposed with the same exposure amount for each gradation pattern.
[0040]
(5) In the above embodiment, for producing a test print, a block of high exposure pixel dots and a block of non-exposure pixel dots are arranged in a staggered manner. Alternating rows with only non-exposed (or low exposure) pixel dots and adjoining high exposure pixel dots and non-exposed (or low exposure) pixel dots, etc. Various arrangement patterns of pixel dots for adjoining a pixel dot having a high exposure amount and a pixel dot having no exposure (or a low exposure amount) can be changed.
[0041]
(6) In the above embodiment, a case where a general densitometer is used for measuring the density of the test print having the above-described configuration is exemplified. You may make it measure the density | concentration of only the pixel dot part of exposure amount.
The test print may be measured with a colorimeter having a density measuring function.
(7) Although the laser beam exposure type exposure head 13 is exemplified as the exposure head 13 in the above embodiment, for example, an exposure head equipped with a PLZT optical switch array, etc. The present invention can be applied when an exposure head of the type is used.
[0042]
【The invention's effect】
According to the configuration of the first aspect, the exposure color having the lowest density value at the maximum exposure amount is specified, and the tone value corresponding to the maximum exposure amount is set to the black tone value for the exposure color. For other exposure colors, the gradation value for which the density value that is the same as or sufficiently close to the lowest density value can be obtained so as to balance the exposure color with the lowest density value. By obtaining from the measured density value of the pattern, the black tone value to be input to the color management system can be accurately set without depending on the skill level of the operator.
[0043]
According to the configuration of the second aspect, in the set gradation changing pattern, the high exposure amount pixel dot of the set gradation and the non-exposure or low exposure pixel dot are set adjacent to each other. This makes it possible to accurately detect a deviation in color balance between exposure colors even in a high-density gradation part where accurate density measurement is not easy, and to accurately identify a black gradation value. .
[0044]
Further, according to the configuration of claim 3, by setting a formation pattern of the high exposure pixel dots and the non-exposure or low exposure pixel dots, the high exposure pixel dots are set. The color bleeding from the surroundings to the surroundings can be detected with good balance in the vertical and horizontal directions, and the color balance deviation can be detected with higher accuracy.
Further, according to the configuration of claim 4, the color balance is accurately adjusted in the photographic printing apparatus provided with the laser beam exposure type exposure head in which color bleeding from the pixel dots having a high exposure amount is likely to occur. It can be performed.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a photo print apparatus according to an embodiment of the present invention.
FIG. 2 is a diagram showing a pixel dot array of a test print according to an embodiment of the present invention.
FIG. 3 is a diagram showing an example of density measurement of a test print according to an embodiment of the present invention.
FIG. 4 is a diagram showing a test print according to the embodiment of the present invention.
FIG. 5 is a flowchart according to the embodiment of the invention.
FIG. 6 is a schematic block diagram of an image exposure apparatus according to an embodiment of the present invention.
[Explanation of symbols]
BB Black balance management means
EX Image exposure equipment
PS Photosensitive material
5a monitor
13 Exposure head
51 Simulated arithmetic unit
52 Image processing apparatus

Claims (4)

An image exposure apparatus that exposes and forms a color image by irradiating a photographic photosensitive material with light of a plurality of exposure colors; an image processing apparatus that converts input image data into image data for exposure by the image exposure apparatus; A simulation operation device that simulates an image formed on the photosensitive material based on the input image data, and a monitor that displays a simulated image obtained by the simulation operation device,
A photographic printing apparatus, wherein the image processing apparatus includes a color management system for matching a color of the simulated image displayed on the monitor with a color of an image formed on the photographic light-sensitive material. ,
A density measuring device for measuring the density of an image formed on the photographic material;
Black balance management means for obtaining a gradation value corresponding to black and inputting it to the color management system,
The black balance management means causes the image exposure apparatus to perform an exposure operation with image data having a set gradation change pattern, and based on a measurement result of the density measurement apparatus for an image formed on the photographic photosensitive material by the exposure operation. In the density measurement value of the portion where each exposure color is exposed at the gradation value corresponding to the maximum exposure amount, the lowest density value among the color development corresponding to each exposure color and the exposure color having the lowest density value And specify the tone value that gives the density value that is the same as or close to the lowest density value in other exposure colors, and the tone value of each specified exposure color corresponds to black in the color management system A photographic printing apparatus configured to input a gradation value to be input. The image exposure apparatus includes an exposure head capable of irradiating light in pixel dots,
The black balance management means is set so that a pixel dot having a high exposure amount and a pixel dot having a non-exposure amount or a low exposure amount are adjacent to each other at least in a high exposure amount side portion of the set gradation change pattern. The photographic printing apparatus according to claim 1. In the set gradation change pattern, the black balance management means includes one or a plurality of pixel dots each including a high exposure pixel dot and a non-exposure or low exposure pixel dot of the set gradation. 3. The photographic printing apparatus according to claim 2, wherein the photographic printing apparatus is set so as to be alternately arranged vertically and horizontally. 4. The photographic printing apparatus according to claim 2, wherein the exposure head comprises a laser beam exposure type exposure head.

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