JPH0341578A - Color image reader - Google Patents

Abstract

PURPOSE:To automatically and accurately set a reference value by providing a color mark, reading the color specification of the color mark before reading a color image, and selecting data in which a remarkable characteristic appears by first and second selection means. CONSTITUTION:The reader is equipped with a scanner 1 which scans the image of a drawing E stretched on a drum D optically, a photoelectric conversion part 2 which converts reflected light to an electrical signal corresponding to a light quantity, an arithmetic circuit 4, and a processor 5 consisting of a microcomputer, etc. And the maximum and minimum values are extracted at every filter and color mark, and a color whose minimum value is larger than the maximum value of another color and the color whose maximum value is less than the maximum value of another color are selected at every filter as the first selection means, and the color with the largest maximum value and the color with the smallest minimum value out of the colors other than the one selected with the first selection means are selected. Thereby, it is possible to automatically perform the judgment and setting of the color specification of the color image.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color image reading device for reading drawings drawn in color.

[Conventional technology]

A color image reading device that reads a color image drawn on a drawing irradiates the color image with a light beam and converts the reflected light into -
By introducing the light into a row of multiple dichroic mirrors arranged in a row, converting the amount of reflected light reflected from each dichroic mirror according to the color of the image into a digital value, and comparing this converted data with a reference value. It is configured to identify images and their colors.

In such a color image reading device, the above-mentioned reference value is an important value for specifying a color, and this reference value is determined by selecting an appropriate reference color from the image and using each of the dichroic mirrors of that reference color. is determined based on the digital value of the amount of reflected light.

[Problem to be solved by the invention]

Incidentally, color judgment is greatly influenced by the type of writing instrument, the state of ambient brightness, the quality of paper, etc., and the selection of reference colors also shows large individual differences.

Therefore, even if the above reference value is set in advance, this reference value cannot be commonly used for all drawing readings, and therefore the operator must adjust the reference value for each drawing reading. There was a problem.

The purpose of the present invention is to solve the problems in the above-mentioned prior art,
An object of the present invention is to provide a color image reading device that can automatically determine and set the color type of a color image.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a color image that reads the color image by inputting the reflected light from the color image to a plurality of filters and converting the reflected light of each filter into an electric signal corresponding to the reflected light. The reading device includes color marks of a plurality of different colors, color mark reading means for reading optical signals at a plurality of points for each of these color marks for each filter, and color mark reading means for each of the filters and for each color. extraction means for extracting the maximum and minimum values of a signal read by the filter; and for each of the filters, a color in which the minimum value is greater than the maximum value of the other colors, and a color in which the maximum value is smaller than the minimum value of the other colors. a first selection means for selecting a color having the largest maximum value and a color having the smallest minimum value among colors other than the colors selected by the first selection means for each of the filters; A selection means is provided.

[Effect]

Before a color image reading operation, the colors of a plurality of color marks set in advance Lj are read. This color mark reading is performed by collecting the amount of light reflected from each of a plurality of filters at a plurality of points for one color mark. The number of collected data is 3 times the number of color marks, the number of filters, and the number of data collection points for one color mark.
It is the product of Regarding these data, first, the maximum value and minimum value are extracted for each filter and each color mark. Next, for each filter, select colors for which the minimum value of one color mark is greater than the maximum value of another color mark, and colors for which the maximum value of one color mark is smaller than the minimum value of another color mark. Select. Next, excluding these selected colors, the color with the largest maximum value and the color with the smallest minimum value are selected for data in other color marks. After these selected color data are stored, the actual color image is read and the selected color data is used as a reference value.

〔Example〕

Hereinafter, the present invention will be explained based on illustrated embodiments.

FIG. 1 is a schematic diagram of a color image reading apparatus according to an embodiment of the present invention, and FIG. 2 is a perspective view of a drum on which a drawing is mounted. 1 is a scanner that optically scans the image of the drawing E stretched over the drum D. The drum D can rotate in both directions, and the scanner 1 can move in the direction of the arrow. The scanner 1 is equipped with a plurality (P) of dichroic mirrors F1 to Fp and a photoelectric conversion section 2 that converts the reflected light from the dichroic mirrors into an electrical signal according to the amount of light.

Note that the dichroic mirrors F and ~Fl are filters that have the function of reflecting light of a specific color and passing the others, and other filters may be used as long as they have the same function. 3 is an A/D converter that converts the signals of the dichroic mirrors F, ~Fl, of the scanner l into digital values; 4 is an arithmetic circuit that performs necessary calculations such as adding weight to input values; and 5 is an arithmetic circuit that performs necessary calculations such as adding weights to input values. A processing device 6 is more powerful than a microcomputer, and numeral 6 is a display unit that displays processing results of the processing device 5. As shown in FIG. 2, M color marks 01 to CM are added to the blank area on the side of drawing E. These color marks C1 to CH are each made of a different color and are arranged at predetermined positions.

Next, the operation of this embodiment will be described with reference to the flowchart shown in FIGS. 3(a) and (b), the data extraction diagram shown in FIG. 4, and the data arrangement diagram shown in FIGS. 5(a) and (b). I will explain. First, by driving the scanner 1 and drum D, color marks 01 to C8 on drawing E are read (step S shown in FIG. 3(a)).

This reading is performed at a plurality of points, for example, N points, for each color mark. Therefore, the number of data obtained as a result of reading is the product of the number M of color marks, their reading points N, and the number P of dichroic mirrors (MXNXP
). The signal obtained in this way is converted into a digital value by the A/D converter 3, and the required calculation is performed on the converted data by the arithmetic circuit 4 (step S2).
. Note that the calculation by the calculation circuit 4 can also be performed by the processing device 5.

Regarding the data obtained in this way, the processing device 5 extracts the maximum value and minimum value for each color and each dichroic mirror (step S: +). This extracted data (2XM
XP) are shown in FIG. In FIG. 4, the maximum value is represented by A and the minimum value by B, and the upper part of these two-digit subscripts represents the color number of the color mark, and the lower value represents the number of the dichroic mirror. For example, for color mark C7, among the data of N reflected lights from dichroic mirror Fl, the maximum value is AHP, and the minimum value is BMP.
It is expressed as Furthermore, in Figures 5(a) and (b),
Among the collected data, data from the dichroic mirror F and the dichroic mirror FP are shown by an array of lines to facilitate understanding of subsequent processing. In FIGS. 5(a) and 5(b), data regarding five color marks C+, Cz, C3, C4C, and 4 are shown, with data values set to be large on the left and small on the right.

When the maximum value and minimum value data are extracted in step S3, first, one color is extracted from the data of the dichroic mirror F1, and the operation of subtracting the minimum value of each other color from the maximum value of that color is performed for each color. (Step S4), and it is determined whether there is any color for which the calculation result is negative for any other color (Step S,). In the case shown in FIG. 5(a),
Since there is no such color, the process moves to step S.

Note that if there is a color for which the calculation result is negative with respect to any other color, this color is stored as a color of recognition level 1 (step S).

Next, regarding the data of the dichroic mirror F1, an operation of subtracting the maximum value of each other color from the minimum value of one color is performed for each color (step S), and the calculation result for any other color is It is determined whether there is a color for which is positive (step 5Il).

In the case shown in FIG. 5(a), color C2 satisfies this condition. In other words, the minimum value B□ of color C2 is the same as that of other colors C1°C3,Ca
, CH minimum value AII+A31. Since it is larger than any value of A□+AMP, the subtraction result is positive. This color C2 is stored as recognition level 1.

In the end, the processes from Steps 84 to S9 are processes for selecting a color that is clearly distinguished from other colors by the dichroic mirror F1. Similar processing is performed for the other dichroic mirrors F2 to FP (step 5ho).

Through this process, for example, for the dichroic mirror Fp, as shown in FIG. 5(b), step 34. It is clear that color CI4 is selected as recognition level 1 by the same processing as SS.

Among the colors selected as the recognition level (2) in this way, there are colors that are selected redundantly in a plurality of dichroic mirrors. In step sII, this is determined, and if there is an overlap, the difference between the maximum value and the minimum value is calculated for each dichroic mirror for the same color selected twice, and only the one with the largest difference is retained. The others are deleted (step s1□).

Then, each remaining color is registered as recognition level 1 (step S1.).

Next, colors that can be further distinguished are selected from colors other than the colors registered as recognition level 1. First, compare the maximum value of each color for dichroic color F1 (Step 514), and select the color with the largest maximum value at recognition level 2.
(Step S5.). In the case shown in FIG. 5(a), color c2 is excluded as recognition level I, so
Color c1 corresponds to this. Next, for the dichroic mirror F1, compare the minimum value of each color in step s, 6)
, the color with the smallest minimum value is stored as recognition level 2 (step S1.). In the case shown in FIG. 5(a), color CM is excluded as recognition level 1, so color C3 corresponds to this. Step 314 ~ Sl? The same process as above is performed for the dichroic controllers F2 to FF (step S
, 8). For example, regarding the dichroic mirror F, in the case shown in FIG. 5(b), the color C3 with the largest maximum value and the color CI with the smallest minimum value are selected. The color selected as recognition level 2 is a color that can be distinguished from other colors.

Here, it is determined whether or not there is any overlap among the colors selected as recognition level 2 (step S1). In the case shown in FIGS. 5(a) and 5(b), colors C+ and Cff are selected overlappingly by dichroic mirrors Fl and FP. In such a case, only one is left and the others are deleted in step S2°. That is, for the color C8 selected as the color with the largest maximum value in the dichroic mirror F, the difference between the two maximum values α+ (Az A,
) is calculated, and then the absolute value of the difference between the minimum value of color C5 and the minimum value of color C4, which has the second smallest minimum value, in dichroic mirror F, , 1α2 + (lB+
p-84,1) is calculated, and the absolute values of these differences are compared. Since 1αzl>α1, the color C1 in the dichroic mirror F remains, and the color CI in the dichroic mirror F1 is erased.

Similarly, for color C1, dichroic color F,
, F, the difference β1. β2 is calculated, β2〉1β,
1, so the color C in dichroic mirror F9
3 is left, color C3 in dichroic mirror F1
will be deleted.

When the redundantly selected colors are erased, the color with the second largest maximum value and the color with the second smallest minimum value in each dichroic mirror F, ~Fl are selected and stored as mixable colors. .

These colors are used as additional information. For these mixable colors, step SI4+ Sl? may be selectively stored during processing.

Finally, each color selected as recognition level 2 and mixable color is registered (step St□), and colors other than recognition level 1 and 2 are registered as recognition level 3, which indicates that they are unrecognizable colors. (Step S.) Figure 6 (a) to (C)
2 is a diagram showing data registered through the above process displayed on the display section 6. FIG.

Generally, dichroic mirrors are often provided corresponding to three primary colors, so if colors that are far apart in hue are selected as colors for drawing a color image, most colors can be automatically set through the above process. If a more distinctive drawing color is to be used, this can be easily handled by adding a corresponding dichroic mirror.

After performing the above processing using the color marks C1 to C, 4, the color image of the drawing is read. That is,
Dichroic mirror F for pixels with color images
Assuming that the data obtained in steps 1 to F2 are f1 to r, these data r1 to fp are shown in Figure 6 (
It is checked whether the value corresponds to a value between any of the maximum and minimum values of the corresponding dichroic mirror (filter) in the registration table of recognition level 1 as shown in a). If applicable, a corresponding color code is set. If there is no corresponding color, the same process is performed using the recognition level 2 registration table as shown in FIG. 6(b), and a color code is set.

As described above, in this embodiment, a color mark is provided, and before reading a color image, the color of the color mark is read in advance, and the data is registered as recognition levels 1 and 2 in descending order of characteristics. Since it is used as a reference value when reading color images, there is no need for the operator to adjust the reference value each time reading is performed, and this can be done automatically and accurately, significantly reducing the burden on the operator. can do. Further, since the processing results by the processing device can be displayed on the display unit, it is possible to determine which colors cannot be used and to obtain suggestions on measures to be taken to enhance recognition of specific colors.

In addition, in the explanation of the above embodiment, when there are duplicate colors in the selection of recognition level 1゜2, an example was explained in which one is left and the others are deleted. If a method is adopted in which the recognition level data is sequentially compared, even if there are duplicate colors, there will be no problem with the judgment.

[Effect of idea]

As described above, in the present invention, a color mark is provided,
Before reading the color image, the color type of the color mark is read, and the data in which the characteristics appear prominently are automatically selected by the first selection means and the second selection means, and these data are used as reference values. Therefore, there is no need for the operator to adjust the reference value when reading a color image, and the reference value can be automatically and accurately set, thereby significantly reducing the burden on the operator.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a color image reading device according to an embodiment of the present invention, FIG. 2 is a perspective view of a drum on which drawings are stretched,
3(a) and 3(b) are flowcharts explaining the operation of the device shown in FIG. 1, FIG. 4 is a data extraction diagram, and FIG.
Figures (a) and (b) are data layout diagrams, Figure 6 (a),
(b) and (c) are diagrams showing displayed registration items. ■...Scanner, 2...Photoelectric conversion unit,
3...A/D conversion section, 5...Processing device, F, ~Fp...Dichroic mirror, CI
"" CM...Color mark, E...
Drawing, D...Drum diagram (α) Figure 3 (b) Figure

Claims (1)

[Claims] In a color image reading device that reads the color image by inputting reflected light from a color image to a plurality of filters and converting the reflected light of each filter into an electric signal corresponding to the input, color marks of a plurality of different colors and , color mark reading means for reading optical signals at a plurality of points for each of these color marks for each filter, and maximum and minimum values of the signals read by the color mark reading means for each filter and for each color. an extraction means for extracting, a first selection means for selecting, for each of the filters, a color in which the minimum value is larger than the maximum value of the other colors and a color in which the maximum value is smaller than the minimum value of the other colors; A second selection means is provided for selecting the color with the largest maximum value and the color with the smallest minimum value among the colors other than the colors selected by the first selection means for each filter. Color image reading device