JPS585744A - Method and device for classification of original as well as tone setup method of electronic color separator and device used for it - Google Patents

Abstract

PURPOSE:To improve tone setup efficiency by comparing the standard patterns stored in a memory and the pattern based on the density distributions of an arbitrary original and discriminating the most approximate standard patterns. CONSTITUTION:The scanned outputs of printed matter are processed in the signal processing part 81, arithmetic part 82, etc. of a microcomputer 8, and the standard patterns corresponding to the color densities of the printed matter are stored in a memory 83. In the same manner, the similar pattern of an original 1 scanned via a light source 3 is stored in the memory 83, and the memory 83 is controlled by a control panel 11, so that the standard patterns and the original pattern are displayed in superposition on the cathode ray tube 10. The most approximate standard patterns are discriminated successively, whereby the originals are grouped easily and quickly in accordance with the differences and resemblances in their density distributions, and the tone setup is accomplished at high speed, with accuracy and high efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for classifying color or monochrome originals (hereinafter referred to as originals) based on differences in density distribution, and an automatic color separation machine (hereinafter referred to as originals) for obtaining printed matter of a desired tone from the original. The present invention relates to a method for setting up a tone reproduction curve of a scanner (referred to as a scanner) based on the density distribution of an original, and an apparatus therefor.

The first object of the present invention is to measure the density distribution of a document, classify it into groups based on differences and similarities in the density distribution, and operate a scanner or color separation camera for each grouped document group. The present invention provides a document classification method and device for improving work efficiency and ensuring high quality products.

A second object is to provide a method and apparatus for setting up a tone reproduction curve that can simplify the work process for setting the tone reproduction curve of a scanner and allow quantitative processing.

When printing in multiple colors based on a ambiguous original, the original is color-separated into negatives or positives for each color plate in order to create plates for each color. Currently, many scanners are in use that continuously scan a transmissive or reflective original and effectively perform masking, various color corrections, etc. using electronic circuits using electronic techniques.

The scanner is a useful device for significantly shortening the plate-making process and producing extremely high-quality printed matter, but it does have some problems.

One of them is that there are a wide variety of originals, and they all have different color characteristics and density characteristics. It is not possible to simply set such an original in a scanner and press a button to immediately obtain the desired color separation negative or positive. The reason for this is that the color characteristics of the original color materials and the color materials used for printing are different.
This is particularly due to the fact that their concentration ranges are different. = Generally, the density range of dyes in color film originals is wide, and the density range of printing inks colored with pigments is narrow. Therefore, when producing separation negatives from color film originals, the density range must be reduced. Furthermore, in planographic printing, the shade of color is expressed by the size of the halftone dots, but the density in the original is not directly proportional to the size of the halftone dots on the plate. Therefore, in order to express the tone of the manuscript or the desired tone on print,
It is necessary to obtain an appropriate tone for intermediate colors, and to make strict adjustments to highlights and shadows.

Currently, the density of the highlights, shadows, and middle areas is measured using a density measuring device, and based on the values obtained, it is possible to determine the range of the density in the disassembled film, and to what extent. The adjustment section of the scanner is operated by checking with past experience values to see if the density curve value can be used to produce the best prints as desired.

However, this tone reproduction curve adjustment is performed using many adjustment dials, and the combinations of adjustment amounts on these adjustment dials are countless, and it takes a highly skilled person and a considerable amount of time to properly perform this adjustment. It takes.

Conventionally, it has been common practice to perform color separation by setting the tone adjustment section of a scanner for each document, and currently less than 40% of products are suitable for use. In the scanner department, in order to improve the operating efficiency of expensive scanners, skilled color retouchers internally observe a large number of manuscripts, and depending on experience and knowledge, they are divided into several groups based on differences in density distribution throughout the manuscript. classified into
The adjustment section of the scanner is adjusted to a certain adjustment value for each group of classified documents. However, the operating rate is still as above.

In addition, if the finish is poor, we change the adjustments and make a custom version.

As described above, requiring a long adjustment time and skilled personnel, and using a large number of plate-making films causes a decrease in work efficiency and an increase in costs.

In view of the above points, the present inventors have proposed a method and apparatus that have a synergistic effect of using a scanner more effectively, shortening work time, and obtaining better printed matter. A method and device for accurately and quickly classifying a wide variety of manuscripts into groups characterized by differences in distribution by processing the densities of a large number of manuscripts in a rechargeable manner and using a microcomputer or other sensor. Once completed, a few other elements may be added to the document sorting method and apparatus, including a method for setting up a tone reproduction curve of a scanner to obtain prints with desired tones from any document; We have completed the equipment used for this purpose.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a block diagram illustrating one embodiment of an apparatus that can be used both for document classification and for setting up a scanner's tone reproduction curve.

FIG. 2 is a diagram showing an example of a device for loading a document.

Figures 5-1 to 3-10 in Figure 6 are diagrams of printed matter a+J based on differences in cumulative density distribution, Figures 4 to 7 are diagrams illustrating normalization of transparent original patterns, and Figure 8 is printed matter. FIG. 9 is an explanatory diagram for calculating the tone reproduction curve of the scanner from the standard pattern and the original pattern obtained from the standard pattern and the original pattern. FIG. . The document classification method shown in FIG. 1 consists of the following components.

Document +11 is attached to the document loading section (2). As an example of the document mounting section, as shown in FIG. 2, a cylindrical document mounting section that rotates in the circumferential direction and moves in the axial direction can be used. When the original (1) is pasted on the surface, a light source is irradiated from inside. The light source (3) is placed outside the document loading section (2), and the lens (4) focuses the light into a parallel beam, and a slit (not shown) turns it into a spot beam (5) inside the document loading section (2). The light may be reflected by a provided mirror (6) and irradiated onto the original (1). Also,
When the original mounting portion (2) is made of an opaque material, a cutout hole corresponding to the size of the original may be provided and the original may be mounted by blocking the hole. The transmitted light (?) is guided to the concentration measuring means (V,). And transmitted light (7)
When measuring as visual light, 7 volts (V)K of the photoelectric converter is guided through 0 total reflection mirrors and a visual filter (V'). In the case of visual side illumination, density is expressed by a single signal even for a color original as perceived by the human eye. Also, 8・d.

If you want to separate the original into three colors, Gr...n and Bin, and measure the density of each color, use a mirror (for the sake of caution, use a semi-transparent mirror (R') to convert the transmitted light (7) into , (G'), (
Through B and filter (R, (G, (B')),
Photomaru (R), (G), CB) K guidance standard 1, G respectively
, B. Measure the density of the color components.

The light incident on the photomultiplier (V) is converted into an analog electrical signal and input to a microcomputer (8) having various calculation, storage, and output functions.

Electrical signals according to the concentration are generated by a computer (8)
The input signal is input to the input data processing section 〇, where the input signal is divided by a separator (not shown) for dividing the entire concentration range into an appropriate number of divided concentration ranges. The divided signals are counted by counters provided corresponding to the respective divided concentration ranges. Each counter is self-held until it receives another command signal, that is, a signal indicating that the density measurement of the document is completed. At this point, the density distribution of the original has been shifted to the needle side. Note that when scanning a document, the light source and light receiving section must be identified, and the document loading section (
2) by sliding it in the axial direction at a constant pitch each time it rotates, or by simply rotating the document loading section (2) and sliding the mirror (6) of the light source system and the light receiving section of the 7 otomaru in synchronization. A method of scanning in a spiral manner may also be used.

In addition, in order to measure one spot of the original, the analog electrical signal obtained by the photomultiplier and the sampling pulse of a certain frequency must be connected to an AND circuit. The signal is input to the next calculation section, which calculates what percentage of the entire document is occupied by the density portion belonging to each divisional density range, or calculates the density distribution value of the divisional density range in order of density value. A cumulative concentration distribution is obtained by integrating the above, and a 100th ratio is obtained for each of the above-mentioned aircraft sectional concentration ranges, or a relative ratio of the sectional concentration ranges is obtained. Determining the percentage or relative ratio in this manner is hereinafter referred to as patterning the concentration distribution. The signal patterned in this way is stored in the storage section.

The stored patterns are displayed graphically or numerically by a CRT display device, as required.

Various methods can be used for classifying documents based on differences in density distribution. One method is to draw some standard patterns obtained from printed matter with representative tones on the surface of the CRT device in advance, and then transfer the measured original patterns to the CRT device.
The document can be classified by displaying it on the device and determining which of the pre-drawn patterns this document pattern is close to. The other method is to store representative standard patterns in the memory of the computer, display the actually measured original pattern on the CRT device, and call up the stored representative standard patterns one after another in the same way. By superimposing the document on the CB'r device, it is possible to classify any document by determining which standard pattern it is the same as or similar to.

Furthermore, if necessary, the printer can be driven by the output section of the computer to print out the pattern in the form of a graph or as numbers or characters.

Next, a method for setting up a tone reproduction curve for a scanner and the equipment used for this purpose will be described.

In view of the drawbacks of the conventional tone reproduction curve setup for the scanner, the present inventors simplified the setup operation and divided it into standardized tasks.
Even if there is a slight addition of equipment or an increase in the number of pre-processes, if even an inexperienced scanner operator follows the established procedures, the overall process can be completed in an extremely short time and accurately. A method and device for setting up the tone reproduction curve of a scanner was developed.

The present invention was made based on the following recognition: By observing and analyzing a wide variety of manuscripts with a focus on density distribution, it is possible to classify them into several types, and printed matter can also be analyzed based on density distribution. It has been demonstrated that it can be classified, and as a result of measurements on many printed materials, it has been found that it can be classified into about 10 types as shown in FIG.

Note that FIG. 5 shows one pattern of concentration distribution in which the relative concentration is expressed as kI 00 percent on the horizontal axis, and the cumulative concentration distribution is expressed as 100 percent on the vertical axis.

The present invention is based on the above recognition and includes the following steps for obtaining a print of a desired tone from an arbitrary transparency document, which may be a tone different from that of the document. This is how to set up a scanner's tone reproduction curve.

The first method includes the following steps a to C.

a. Select multiple standard prints with different tones from a large number of prints, find the cumulative density distribution of each print with scissors,
Next, this cumulative density distribution is patterned to create standard patterns corresponding to standard printed matter, and the setting values of the tone reproduction curve of the scanner corresponding to these standard patterns are determined in advance.

A step of determining the cumulative density distribution of an arbitrary transparent original to be subjected to b99 color separation in the same manner as in a above, and creating a pattern of the arbitrary transparent original normalized to 5 so that it can be compared with the standard pattern.

C0 Compare the pattern of the arbitrary transparent original obtained above with the plurality of standard patterns obtained in step a above, or compare the pattern of the arbitrary transparent original with the tone modulation comments of the original added to the standard pattern, A step of selecting one standard pattern that is most similar to the arbitrary transparent original pattern and setting the tone reproduction curve of the scanner based on the setting value of the tone reproduction curve corresponding to the standard pattern determined in step a.

The second method includes steps a to f below.

a. Select a plurality of standard prints with different tones from a large number of prints, and find the cumulative density distribution of the prints of each skeleton,
Next, a step of patterning this cumulative density distribution to create a standard pattern corresponding to a standard printed matter.

b1 Step of determining the cumulative density distribution of the arbitrary transparent original to be separated into colors in the same manner as in step (a) above, and creating a normalized pattern of the arbitrary transparent original so that it can be compared with the standard pattern.

C. Setting the tone reproduction curve of the scanner to a reference tone reproduction curve using gray scale.

d. Comparing the pattern of the arbitrary transparent original obtained above with the plurality of standard patterns obtained in 1 above, and selecting one standard pattern that is most similar to the arbitrary transparent original.

・Determining a tone reproduction curve for printing an arbitrary transparent original in the tone of a selected standard printed material from an arbitrary transparent original pattern and a selected standard pattern, and calculating a difference between the tone reproduction curve and the reference tone reproduction curve. .

f. A step of correcting the reference tone reproduction curve based on the values obtained in the above.

The third method is a method consisting of steps a to d of the second method and steps . and f below.

・Comparing the arbitrary transparent original pattern with the selected standard pattern, calculating the difference between the two, that is, the difference in cumulative density distribution, and replacing the difference value with a numerical value for setting the tone reproduction curve of the scanner.

° This is the process of correcting the previously set reference tone reproduction curve with the value obtained in .

When creating a standard pattern in the above method for setting up a tone reproduction curve for a scanner according to the present invention, please pay attention to the following points: Each of the selected prints is selected from a wide range and is of good quality. It is. And they contain representative objects and representative tones.

Although the selection of such printed matter requires great care, - the standard pattern determined can be used repeatedly in the future unless there are special circumstances, which reduces the value of the present invention. It's not something you can do.

In each of the figures 6-1 to 3-10 shown in FIG. 3, the horizontal axis represents the concentration, and the vertical axis represents the cumulative concentration distribution in percentage.

To describe the density on the horizontal axis in more detail, it shows the relative density expressed as a percentage of the density range from the density of the highlight part to the density of the shadow part.

The standard pattern shown in Figure 3-1 has a relative density of 2
The cumulative concentration distribution rate up to 5% is 12.5%, the cumulative concentration distribution rate up to 50% relative concentration is 50%, and the cumulative concentration distribution rate up to 75% relative concentration is 87.5%. It shows.

In addition, all figures 5-1 to 3-10 have a relative concentration of 25.
A pattern is created by accumulating the concentration distribution amounts for each percentage and plotting the values. Of course, it is optional to increase the number of plot points to create a finer pattern.

Next, the standard patterns shown in FIGS. 3-1 to 6-10 are representative of printed matter having the following tone.

Figure 6-1...Printed material with many middle parts Figure 3-2...
...Printed material with many bright areas Figure 6-3...Printed material with uniform brightness and darkness shown in Figure 3-4...
・Printed material 3-5 mainly depicts dark areas...
...Printed material consisting mainly of bright and dark areas...Figure 3-6...
- Figure 3-7 is a printed matter that mainly expresses the middle part rather than the bright part...
. . . P1 Akiharu is expressed in a uniform ratio, but 2-
A print that is brighter than the one in Figure 5. Figure 3-8: The print is mainly from the middle part to the dark part. Figure 3-9: The main part is from the middle part to the dark part K. However, the printed matter is brighter overall than the one in Figure 8. Figures 5-10... The brightest printed matter with the center of the bright area This section describes pattern normalization when creating a manuscript pattern.

The cumulative density distribution is automatically obtained by operating the apparatus from an arbitrary document, and before it is patterned and compared with a standard pattern of printed matter, preprocessing must be performed for the following reasons.

The reason for this is that the maximum density range of printed matter printed with ink is approximately 2.4 in terms of Macbeth density, whereas the maximum density range of color film originals dyed with dye is 3.2. This is due to the fact that it is considerably wider.

In this way, it is not possible to compare arbitrary originals with different density ranges with standard patterns directly obtained from printed matter. Therefore, in the present invention, a special operation is performed to obtain an arbitrary document pattern that can be compared with a standard pattern obtained from a printed matter. This operation is called normalization of the original pattern. For example, if the cumulative density distribution of an arbitrary manuscript is as shown in Fig. 4, the highlight part (HCP)
r point)) is taken as the H point, the density range up to 8 points obtained by adding 2.4 once to the density of the H point is considered to be the density range of any manuscript, and this density range is expressed as a percentage on the horizontal axis. A document pattern of an arbitrary document is created as shown in FIG. 5, in which the relative density and the cumulative density distribution are shown as percentages on the vertical axis. Further, FIG. 6 shows the once distribution before normalization of another arbitrary document, and FIG. 7 shows the normalized arbitrary document pattern. This normalization work can be performed extremely easily using a computer.

Once a standard pattern and an arbitrary document pattern are prepared in such a manner, the tone reproduction curve of the scanner can be obtained from them. For this purpose, the three methods mentioned above can be adopted. Each will be described in further detail.

One of them is how should the tone reproduction curve of the scanner be used to reproduce printed matter having the tones represented by standard patterns, for example, the standard patterns shown in Figures 5-1 to 3-10. is determined empirically in advance through various measurements and actual work, then the pattern of an arbitrary manuscript is determined, it is compared with the standard pattern, the standard pattern that is most similar to the arbitrary manuscript pattern is selected, and the pattern added to this standard pattern is A scanner tone reproduction helmet equivalent to this one.
Set up the scanner's tone reproduction curve based on the adjustment values of the scanner.

Some Li! Any manuscript pattern takes into account the tone modulation comments attached to that manuscript (
Compare the turn with the standard pattern, select the most suitable standard turn from among the standard turns, and set up the tone reproduction curve of the scanner in the same manner as described above.

The second method is for transmission grayscale ~ 1. The tone reproduction curve of the scanner is set as the reference) -y reproduction curve at the peak where a printed grayscale having the density distribution according to the transparent grayscale is obtained. I'll keep it. next,
A tone reproduction curve of a scanner for printing an arbitrary original in the tone of a standard print is determined from an arbitrary original pattern and a selected standard pattern.

How to find this, ft, a four quadrant diagram as shown in Figure 98.
) can be used to find the force t. In the 8th III, the fold line Wtt in the second quadrant indicates the cumulative density distribution curve of a printed matter selected from a large number of printed matter, that is, one of the standard patterns, and the fold line Isw in the fourth quadrant indicates the cumulative density distribution curve of an arbitrary document -
The line, ie, the arbitrary document pattern, is shown, and the curve in the first quadrant shows the tone reproduction curve to be set in the scanner. This tone reproduction curve wheel is the cumulative density distribution curve (end) of the second and fourth quadrants, with perpendicular lines drawn from the points of 25%, 50%, and 75% of the cumulative density distribution of OI to the first quadrant. It is obtained by connecting each intersection point. Then, the differences x, y, and z between the reference tone reproduction curve and the tone reproduction curve of the arbitrary original are determined by a microcomputer. These x, y, and z indicate the amounts to be adjusted from the scanner's standard tone reproduction curve, which is set in advance, in order to print an arbitrary document to the tone of a standard print. This x, y.

2 has no unit, but it is calculated in advance how much the unit length of the vertical axis of this first quadrant corresponds to on the dial for adjusting the tone reproduction curve of the scanner, and this conversion scale is used from now on. Of course, this operation can also be performed by a microcomputer. This second method has the advantage that, unlike the first method, it is not necessary to prepare a tone reproduction curve of the scanner corresponding to each standard pattern. ■
The third method is to obtain the tone reproduction curve of the scanner from the difference in cumulative density distribution between an arbitrary original and a standard printed matter, that is, a difference between an arbitrary original pattern and a standard print.

FIG. 9 schematically shows an example of determining the difference between a standard pattern and an arbitrary document pattern. In FIG. 9, the second quadrant 9 fold line - indicates the cumulative density distribution - line of the printed material, i.e., the standard) turn, and the fourth quadrant fold line (2) indicates the cumulative density distribution - line of the arbitrary manuscript, i.e., An arbitrary document pattern is shown, and the line 1IIIO in the first quadrant shows the standard tone reproduction curve of the scanner. Although the standard tone reproduction curve shows a slightly curved curve in most cases, here we adopt a method of treating it as a straight line to simplify calculations.

The fold lines ■ are the relative fold lines of the standard pattern - and the optional original pattern 4, respectively. This fold 1Iil (to) becomes a straight line if the standard pattern ■ and the arbitrary original pattern 9G are exactly the same, and the line 1Iil (to) is a straight line of the reference)-N raw curve.
Matches l. This means that when the pattern σO of the standard pattern member and the arbitrary document are different and a broken line - is obtained, there is a pupil correlation between this broken line - and the reference tone reproduction curve. That is, the distances x', y', and z' between the four points M, , M, on the broken line and the straight line are the standard pattern.
It shows the difference in the cumulative density distribution at each point of the arbitrary original pattern σO, and also shows how to correct the arbitrary original pattern σ which has the same tone as the standard pattern. However, since [Tx', r, and τ represent the magnitude of the cumulative concentration distribution as a percentage, the obtained Y', Y', and 2
It is necessary to convert ' into an adjustment value of the tone reproduction curve. The conversion formula used for this conversion varies depending on the individual scanner, but once it is determined, it can be used repeatedly. The above x', y', and 2' can be easily determined using a microcomputer, and if the conversion formula is also stored in the computer, it is possible to immediately determine how much the reference tone reproduction curve member should be modified. .

By scanning and color-separating an arbitrary document using a scanner with a tone reproduction curve set up using the above method, it is possible to create separated negatives or positives that produce prints with the desired tone.

k. The apparatus used in the method for setting up the tone reproduction curve of the scanner described above will be described with reference to FIG.

The document density measuring means consists of a document loading section (2) for attaching the document (1), a light source (31), and a photoelectric converter. (81K is input, various calculations are performed, the concentration distribution is determined, and it is stored or output as a patterned signal. The arbitrary value measured and determined is determined by the command signal from the operation box aO connected to the microcomputer. The original pattern and the stored standard pattern of printed matter are displayed on the CRT monitor at any time. Various data are printed and displayed by the printer (9). Also, the difference between the plural patterns is calculated and output.

The method for measuring concentration will be described in detail. FIG. 2 shows an example of this, in which a document 111 is attached to a non-transparent cylinder-shaped document loading section (2). However, the document loading section (2
1 has a cutout hole, and align the hole with the original +1
1 is installed. The document loading section (2) is rotated by a motor, and is slid at a constant pitch in the axial direction each time it rotates. The light from the light source (3) passes through the lens (4
1 into parallel light beams, a slit (not shown) turns the light into a spot light (5)K, and the light beam travels straight to a mirror (6) provided inside the document loading section (2). The spot light (5) is reflected by the mirror (6) and projects the original (11) from the back side.The transmitted light (7), which is weakened according to the density of the original +11, is polarized by the total reflection mirror VIK and sent to the visual filter. ffA of the charging converter through V'
(V) and is converted into an electrical signal according to the intensity of the transmitted light (7), that is, according to the density of the measurement point on the document. In this case, the light source (3), lens (4), Mi9-(61, <v'>,
For the photo frame A (V') and the photo frame A (V), only the original mounting (2) rotates and slides during identification. In addition, R
@d, Gr@Hata, If you want to measure the density of each color Blue, fold down the mirror α and make the transmitted light (7) semi-transparent. -(R, (0' input Of>IK guide?!,:
y Ilter ff), (G'), (B') to obtain the density signal of each color by Photomul (R), (G), (B).

The method for scanning the original is not limited to the above-mentioned method, but the original 11) can be scanned in a spiral by rotating the original loading unit (11) and moving the spot light that projects the N original in synchronization with the light receiving unit such as a 7 otomaru. Alternatively, the document may be stopped on a flat surface and the light source and the light receiving section may be linearly moved back and forth.

Next, the functions of the microcomputer (8) will be explained.

The continuous analog concentration signal measured by the concentration measuring means is converted into a discontinuous analog concentration signal by a pulse transmitter AS and an AND gate A, and then input to the input data processing section 9 of the microcomputer. . The input data processing section υ uses a separator to sort and classify each density signal into an appropriate number of predetermined density ranges according to the magnitude of the signal. The signal after division may be a pulse (l-j) of a constant level regardless of the concentration. These constant-level pulse signals are counted and digitally processed by a pulse counter provided corresponding to each divided concentration range. Note that the separator used is one whose setting point can be moved vertically in parallel. At this point, the concentration distribution has been measured, or since it is difficult to process it as it is, various calculation processes are performed in the calculation section (2) in the next stage. The calculation unit receives a signal corresponding to the count number for each divisional density range from the input data processing unit 6υ, and calculates the density distribution ratio indicating what percentage of the entire document is occupied by the density portion belonging to each divisional density range. , or calculate the cumulative concentration distribution by integrating the concentration distribution values of the divided concentration ranges in the order of concentration values, and calculate the cumulative concentration distribution rate expressed as a percentage for each divided concentration range in the same manner as described above.

Alternatively, the relative ratio for each sectional concentration range may be determined. That is.

Regarding the distribution of each manuscript, [patterning and calculation section]
A correction value of the reference tone reproduction curve, etc. can be calculated from the difference between the standard pattern and the arbitrary document pattern, or from these and the reference tone reproduction curve of the scanner.

As mentioned above, the other function of the calculation section is to normalize K so that the standard pattern obtained from the density distribution of the printed matter and the pattern obtained from the arbitrary force 2-transparent original can be compared. In this normalization, first, if the density range of the original exceeds the density range that can be expressed by printing, as shown in Figure 4, the part that is to be expressed brightest in printing is set as the H point, and the 8 points are set for the parts that are intended to be expressed darkly. This measurement is obtained by manually operating the concentration measuring means and digitally displaying it on the point photometry display section (2). This H
Exclude measured density values whose density is smaller than the point and measured density values whose density is larger than the 8 points.

To do this, the separator of the input data processing section is moved in parallel based on the density values of the H point and the 8th point to shift and adjust the boundary value of the segmented density range. Next, the concentration distribution between the H point and the S point is calculated from a cumulative concentration distribution rate of 0 to 1 at a relative concentration of 0 to 100%.
Expressed as 00%. Furthermore, if the density range of the original is small, the above method is reversed.

The pattern determined by the calculation section is stored in the storage section.

The memorized standard pattern or arbitrary document pattern is displayed on the CRT display device (1) (IK) at any time according to the command signal from the operation unit αυ. On this display device, multiple standard patterns and one arbitrary document pattern are displayed in a superimposed manner. This allows you to easily determine which standard pattern an arbitrary original pattern is most similar to.In addition, the storage section stores the value of Xlr%2' shown in Figure 9, which is converted into an adjustment value for the scanner's tone reproduction curve. You can also memorize formulas.

Historically, the measured data or the data subjected to various arithmetic processing can be displayed as graphs or prints by the printer (9) via the output section.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of the device of the present invention, FIG. 2 is a diagram showing an example of the density measuring device, FIGS. 6-1 to 3-10 are diagrams showing the density distribution of printed matter, and FIG. and Fig. 5 is a diagram illustrating normalization of the density distribution of the original.
The figure is a diagram explaining how to obtain the Seratosbeki tone reproduction curve in a scanner from the density distribution of the original and the printed matter. Figure 9 is an explanation of how to obtain the difference in density distribution between the original and printed density distribution curves from the density distribution curve of the original and the density distribution curve of the print. In the figure, (1) is the original, (2) is the original mounting cylinder, (
3) is a light source, (-) is a concentration measuring means, (6) is a mirror,
()) is transmitted light, r is total reflection mirror, ('Ee) (Target (B') kt semi-transmission Mi5-1 (V') (R')
(c') (B') is a filter, (V) (R) (G) (
B) is a photoelectric converter, (8) is a microcomputer-1
(9) is an output device, and the trout is a CRT.龜滲 is the control panel, I is the pulse oscillator, a 謬まAND gate, (2) - is the once distribution curve of the printed matter, @翰 is the original distribution curve, -1 is the standard tone reproduction curve,
-1 is an arbitrary original tone reproduction curve, (x) (Y) (Z
) and (X') (Y') (Z') respectively indicate the difference values between the reference tone reproduction curve and the original tone reproduction curve. Patent applicant Dainippon Ink & Chemicals Co., Ltd. v.1
Plate 1 Figure 2 Figure 1 Figure 1r-E) 0, 6, Z8 Illustration procedure amendment (method) December 2, 1980 Secretary-General of the Bureau of Internal Affairs and Communications Haruki Shimada Tono t Incident display % Peng Sho 56-102295 No. 2, Name of the invention Method and device for classifying manuscripts, method for tone setting of electronic color separation machine, and device used therefor Relationship with the case of the person making the amendment Patent applicant address 55-58 Sakashita 3-chome, Itabashi-ku, Tokyo 174, Japan Mao Date of amendment order (shipment date) November 24, 1980 & Brief description of drawings in the specification subject to amendment & Contents of amendment

Claims (1)

[Claims] E-11 Obtain the density distribution for each of a plurality of printed matter selected from a large number of printed matter, then pattern this density distribution, record the obtained plurality of patterns as standard patterns, and then Pattern the density distribution obtained by the same method as the standard pattern for other arbitrary manuscripts,
The method for classifying documents is characterized in that the arbitrary document pattern is compared with the plurality of recorded standard patterns to determine which standard pattern the arbitrary document pattern is most similar to. B) means for keeping the original concentration constant; means for sorting each measured concentration signal into a plurality of divided concentration ranges that suitably divide the entire concentration range; A device for classifying originals according to differences in density distribution, comprising means for determining density distribution, means for patterning the density distribution, means for storing the pattern, and means for outputting one or more of the patterns by a display system or a printing device. (3) The document classification device according to claim 2, wherein the means for determining the density distribution is a device for determining a cumulative density distribution. (4) A method for setting up a tone reproduction curve of an automatic color separation machine to obtain a printed matter of a desired tone from an arbitrary transparent original, including the following steps a to c. 1 Select multiple standard prints with different tone from a large number of prints, find the cumulative density distribution of each print,
Next, this cumulative density distribution is patterned to create a standard pattern corresponding to the standard printed matter, and the step of determining in advance the setting values of the tone reproduction curve of the automatic color separation machine corresponding to these camphor patterns. b66 Step of determining the cumulative density distribution of the arbitrary transparent original to be separated in the same manner as in step 1 above, and creating a pattern of the arbitrary transparent original by comparing it with the standard pattern and normalizing it by 5. Compare the pattern of the arbitrary transparent original obtained above with the plurality of standard patterns obtained in step a above, or compare the pattern of the arbitrary transparent original with the tone modulation comment of the original added to the standard pattern, A step of selecting one standard pattern that is most similar to the arbitrary transparent original pattern, and setting the tone reproduction curve of the automatic color separation machine based on the setting value of the tone reproduction curve corresponding to the standard pattern determined in step a. (5) A method for setting up a tone reproduction curve of an automatic color separation machine to obtain printed matter of a desired tone from an arbitrary transparent original, including the following steps 1 to f. a. Selecting a plurality of standard prints with different tones from a large number of prints, and determining the cumulative density distribution of each of the prints,
Next, a step of patterning this cumulative density distribution to create a standard pattern corresponding to a standard printed matter. b1 Step of determining the cumulative density distribution of the arbitrary transparent original to be separated into colors in the same manner as in step (a) above, and creating a normalized pattern of the arbitrary transparent original so that it can be compared with the standard pattern. A process of setting the tone reproduction curve of the C0 automatic color separation machine to a reference tone reproduction curve using gray scale. d. Comparing the pattern of the arbitrary transparent original obtained above with the plurality of standard patterns obtained in step a above, and selecting one standard pattern that is most similar to the arbitrary transparent original. Second, a step of determining a tone reproduction curve for printing an arbitrary transparent original in the tone of a selected standard printed material from an arbitrary original pattern and a selected standard pattern, and calculating a difference between the skeleton tone reproduction curve and the reference tone reproduction curve. f. A step of correcting the reference tone reproduction curve based on the values obtained in the above. (6) means for measuring the density of a printed matter or any transparent original, means for sorting each measured density signal into a plurality of segmented density ranges that suitably divide the entire density range, and density signals within the segmented density ranges. means for counting and accumulating for each segmented density range to obtain a cumulative density distribution; a means for normalizing the cumulative density distribution; a means for patterning the cumulative density distribution; An automatic apparatus characterized by comprising a means for comparing patterns and calculating a difference between them, a means for storing data such as a pattern of a printed matter and a pattern of an arbitrary transparent original, and an output means for displaying various data on a display or in print. A device for setting up the tone reproduction curve of a color separation machine. (7) The means for comparing the pattern of the printed matter and the pattern of the optional transparent original and calculating the difference therebetween includes a conversion means for converting the difference value between the two patterns into an adjustment value for the tone reproduction curve of the automatic color separation machine. 7. A device according to claim 6, characterized in that: (8) A means for measuring the density of a printed matter or an arbitrary transparent original, a means for sorting each determined density signal into a plurality of divided density ranges in which the entire density range is appropriately divided, and a means for measuring the density within the cough classification density range. Means for calculating the cumulative density distribution by counting the number of signals and accumulating them for each divided density range, means for normalizing the cumulative density distribution, means for patterning the cumulative density distribution, and a pattern for printed matter and an arbitrary transparent original. means for calculating the correction amount of the reference tone reproduction curve from the pattern of the color separation machine and the reference tone reproduction curve of the automatic color separation machine, means for storing various data, and means for displaying the data on a display (bamboo print display) A device for setting up a tone reproduction curve for an automatic color separation machine, which is characterized by: