JPS62164378A - Color splitting simulation device - Google Patents

Abstract

PURPOSE:To simulate how a dot area ratio goes over at any points in a color transparent original if color splitting conditions are changed by providing a color density-dot area ratio conversion table at every color splitting conditions. CONSTITUTION:A color density measurement means 20 measures a color density at any points in the color transparent original, and the 2nd memory means 30 stores color density data R, G and B. The 1st memory means 10 stores the color density-dot area ratio conversion table, and a color splitting condition selection means 50 selects tables showing necessary color splitting conditions among plural color splitting condition tables stored in the memory means 10. A dot area ratio extraction means 40 searches the color density of the color density-dot area ratio conversion table regarding the coinciding or the most approximating selected color splitting conditions in the 1st memory means 10 with respect to the color densities R, G and B from the 2nd memory means 30, and extracts the dot area ratio corresponding to the color density.

Description

[Detailed Description of the Invention] [Technical Field] Is this invention a transparent manuscript? Printing based on color information obtained by optical measurement? The present invention relates to a simulation device for creating color separation plates of C (cyan), M (magenta), Y (yellow), and Bk (black).

[Technical background]

Many color transparent originals are brought to printing companies as originals for printing. This transparent original is transformed into a halftone image as a color separation plate of four colors, C, M, Y, and Bk, using a transmissive scanner. When separating colors with a scanner, what are the color separation conditions such as highlight and shadow density of color transparent originals, color balance status, etc.? I have to set it.

Is the color separation condition set a scanner? It takes time to set the b''-1 color separation conditions, which is left to the operator, and it is difficult to operate the scanner efficiently, even for the same document.

There are also differences in the set b'' of color separation conditions (because of variations in the finish b'') depending on the operator, which poses a problem.

A problem like this? To solve this problem, various devices for setting color separation conditions are commercially available. But are these devices manuscripts? Since the process is completely defeated, the equipment is large, the processing time is long, and the process is expensive.

[Purpose of the invention]

Does this invention solve the problems of the prior art as mentioned above? In order to obtain reference information for setting one-color separation conditions to solve the problem, a transparent manuscript? A small and inexpensive staining device that can determine the dot area ratio of each color separation plate for printing 2 based on color information such as color A degree obtained by optical measurement? The purpose is to provide

[Summary of the invention]

The present invention, which has been made to achieve the above object, is a color transparent original. When separating colors with a scanner, is the finish condition required to set the color separation conditions? Is there any color information such as R, G, and B colors at the i location to be simulated? Transparent color chart of multicolored numbers that have been changed into several stages? A storage means for storing a table that associates color information and dot area ratio for each color separation condition by performing color separation by changing color separation conditions, and calculating the dot area ratio, and color information for color transparent originals. ? Color information measurement method and color separation conditions? The selected color separation has a halftone area ratio corresponding to the color information in the table that matches or approximates the color/report obtained by the color separation condition selection means and the color separation condition measurement means. What is the halftone area ratio extraction method to extract from the conditions and the obtained halftone area ratio? A color separation simulation apparatus is characterized in that it comprises an output means for outputting.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the second embodiment shown in the drawings.

5g1 is a conceptual diagram of the apparatus of this application, and the first storage means 101 stores a color information-dot area ratio conversion table. For color information, color and chromaticity values obtained by color separation filters for R, G, and B are used. Is the degree of color loss below? Let me explain using an example.

Is this color density-dot area ratio conversion table? To create this, create a transparent color chart that includes the number of colors. This can be easily created using digital color blocks. Typically, this color plotter uses R, G, and B laser light, or filters and radiation.
tube? Use R,G.

B The light tb'-changes in response to each 8-bit data,
Force 5 - Transparent color chart by applying 49 on film? It is something that can be obtained. Here, for example, if R, G, BY are changed every 64 levels, 5'=12
With 5 colors and 32 level changes, 96=729 colors can be created. FIG. 2 shows an example of changes every 64 levels. Next, the transparent color of each color in the color chart you created once 1:! : R, G, B filter? At the same time, the scanner was used to perform color separation d'r and color separation was performed (゛, M, Y.

Bk valley each color halftone area ratio? 4+1 fixed. In this way, R, G, B filter? The selected color and halftone dot rFr
14) +M ITs B4 1> Death story, I-4h 7- - F'+ #1. t
The ll IF x l desired + cod area ratio conversion table may be input from the keyboard or directly from the measuring device, and is stored in advance at a predetermined address in the first storage means. In standard separation, is there only one correspondence between color density and halftone area ratio? What you need to remember is 1. Normally, the separation curve, set point, etc. change, so what is the halftone area ratio that corresponds to these various color separation conditions? It is stored in a table for each color separation condition, and can be used depending on the color separation condition. Is Figure 3 an example of a table? show.

In addition, in FIG. 1, the color density measuring means 120) measures the color flaws at any point on the color transparent original. Is there light on the color transparent original to be measured? The irradiating light source, the transmitted light from the color transparent original, the color filter that separates the light into the three colors of R, G, and B, and the RlG and B light from the color filter? When the light is received, the amount of light is Ll, the electric signal? It is equipped with an optical IF converter that outputs the output, and an OP amplifier that converts this electrical signal into data.

The second recording means 130) stores the color density data of RlG and B (i2:, 4), and the one color separation spiral selection means (50) is stored in the first storage means 110). Is there a table for the required color separation conditions from a table for each color separation condition for the number of films used? Which dot area ratio corresponds to the color density for that condition? It becomes possible to extract f.

The halftone area ratio extraction means +4Ql is a color related to the six conditions of the selected color division of the first storage means 10) that matches or most approximates the degree of R, G, and B coverage from the second storage means side. Concentration-nitrogen point area cycle change ugliness table color 4 degrees? Search and find the dot surface crushing rate corresponding to that color 1 degree? Extract.

Such halftone area extraction means t4 (Jl) can be processed by software using a microcomputer;
The storage means (trout) is RAG, the first storage means 1 (
11 is ROM (EPROM, EEPROM)? You can use it.

Processing in halftone area extraction means L4G? 70 in Figure 4
- Explain in more detail based on the chart.

Regarding the color density input from the second storage means 201, is the color flaw data of the selected color density-dot area ratio odor-changing table? Sequentially read the data and calculate the distance between them seven times. As a result of the distance calculation, the color corresponding to the minimum (direct color density or distance h''-0) is extracted from the halftone area ratio table and output.

Note that if there is no matching color density, the interpolation means reads out the most approximate color density and halftone area ratio and the color density and halftone area ratio in the vicinity thereof, and performs interpolation processing 7.
A dot area expert with a more accurate dot area ratio? It may also be possible to request this information and output it to the output means.

Such interpolation processing is explained in detail in Japanese Patent Application No. 1981-081560 entitled "Dot Area Ratio Determining Apparatus" filed by the present applicant. However, in the above application, the dot area of the table is constant, but in the case of the present device, it is undefined, so the difference in the dot area ratio of the adjacent color must be used.

By using such a device, color transparent originals can be produced.
When separating colors with a scanner, color vacancy for each color separation condition -
Halftone area ratio conversion table? Do you have color separation conditions for any point in a color transparent manuscript? What will the dot area look like when you change it? The 5Ts are being able to simulate and efficiently set color separation conditions.
Becomes Noh.

〔Effect of the invention〕

According to the color separation simulation device D according to the present invention,
What is the percentage of halftone dot area of each color separation plate for any point on a color transparent original? It can be calculated accurately and easily, and it supports various separation conditions in the color separation condition settings in the scanner, so it can be used to simulate separation. Be able to do it well.

Furthermore, according to the device of the present invention, even if the scanner b is different,
By matching the focal area ratio displayed by the device of the present invention, it is standardized and quality can be stabilized.

[Brief explanation of drawings]

Fig. 1 is a schematic explanatory diagram of the present invention (d), Fig. 2 is an explanatory diagram showing example 2 of creating a color chart, Fig. 45 is an explanatory diagram of a color saturation-dot area ratio conversion table, and Fig. 4 is an explanatory diagram of a color chart creation example 2. It is a flowchart of the process in a point area ratio extraction means.

Claims (1)

[Claims] 1) In a device that simulates the finished state to set color separation conditions when color-separating a color transparent original with a scanner, multiple A storage means for color-separating a transparent color chart by changing color separation conditions, determining the dot area ratio, and storing a table in which color information and dot area ratio are associated for each color separation condition, and a color transparent original; a color information measuring means for measuring color information of the table, a color separation condition selection means for selecting a color separation condition, and a color information in the table that matches or most approximates the color information obtained by the color density measuring means. A color separation simulation comprising: a halftone dot area ratio extraction means for extracting a corresponding halftone dot area ratio from among selected color separation conditions; and an output means for outputting the obtained halftone dot area ratio. Device.