JPH07322009A - Picture processor - Google Patents

Abstract

PURPOSE:To eliminate the errorneous judgment of a color and the reading error of a colored part on an original CONSTITUTION:A picture processor separates the colors from picture information obtained by optically scanning the original by a picture read means, outputs the picture of an n-color based on separated information, detects a marker color, recognizes an area from the marker color and outputs the picture obtained by editing and working picture data in the pertinent area. A judgement means 14 judging a chromatic color/achromatic color based on a threshold from picture information, a color separation means 16 judging a hue on the chromatic color and separating the colors and setting means 1, 2, 13 and 15 setting the threshold by a scanning multiplying factor at the time of scanning the original are provided. The threshold by which the colors are separated with the scanning multiplying factor is controlled to an optimum value and the threshold is adjusted to the multiplying factor whose vibration is the largest. Thus, the errorneous judgement of the colors in the specified multiplying factor and the reading error of the color on the original owing to vibration can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention performs color separation from image information obtained by optically scanning a document with image reading means using a full color sensor, etc., and based on the separated information, n colors are used. The present invention relates to an image processing apparatus that outputs an image, or an image processing apparatus that recognizes a region from a marker color, edits and processes image data in the region, and outputs the image data.

[0002]

2. Description of the Related Art In recent years, with the digitalization of color copying machines, two colors are available at a relatively reasonable price, according to the user's request.
Several different types of color copiers have come to be offered, such as full color. Conventional 2-color copiers
Although the developing process is performed twice, the present applicant reads the color on the original with a full-color sensor or the like, separates any color, and performs two-color copying in one developing process. A 1-pass 2-color copying machine has been separately proposed (for example, Japanese Patent Application Laid-Open No. 3-201667, "image recording device").

As a means for recognizing and separating colors on an original used in the color copying machine as described above, a method using two kinds of color filters having complementary colors, a method using a full color sensor, etc. have been proposed. ing. In the former case, for example, the document information as described in the image processing method and apparatus of Japanese Patent Laid-Open No. 62-97467 is color-separated by two kinds of color filters having a complementary color relationship with each other, and the document is based on this signal. This is a method of separating the above specific color. In contrast,
The latter is disclosed in JP-A-5-20726 proposed by the present applicant.
When the hue / saturation is calculated from the data read by the document reading means using a full-color sensor or the like as described in the image recording apparatus of Japanese Patent No. 0, and when the hue / saturation range is determined in advance, This is a method of determining color and performing color separation.

[0004]

FIG. 4 is a diagram showing a configuration example of a full color sensor used for image reading. However, among the above, R (red) and G are provided at predetermined line intervals in the sub-scanning direction as shown in FIG.
There is the following problem in the means for reading an original by using a full-color sensor or the like in which (green) and B (blue) sensors are arranged and separating the colors.

In the sensors arranged at line intervals in the sub-scanning direction, since the positions of the R, G, and B looking at the original are different, a line memory or the like is used to be the slowest in the sub-scanning direction. The line positions are pseudo-matched by delaying the lines in line with the lines.

For example, R precedes R, G, B in the sub-scanning direction.
When scanning is performed using the full-color sensor arranged in the order of n lines at intervals, in order to align the reading position with the slowest B line, use a line memory or the like to set G for n lines and R for 2n. The line is delayed.

In the case of using the reading system having such a structure, when vibrations or the like caused by scanning are applied to the scanning system for scanning an original, the vibrations are generated even if the reading lines are artificially adjusted by delaying them with a line memory or the like. As a result, an output difference of R, G, and B occurs, which causes a problem that an edge is erroneously determined as a color in color separation. In addition, in the marker editing function that edits / edits the image by specifying the area with a marker pen, etc., the marker color is erroneously detected and editing / processing is performed at a position that is not specified, or editing / processing is performed at the specified position. There is a problem that it is not processed. Further, the vibration of the scanning system also varies depending on the scanning magnification, that is, the scanning speed in the scanning direction, and there has been a problem that many erroneous determinations occur only at a certain specific magnification.

The color separation method is described in JP-A-62-9.
Judgment is made by calculating (RB) and (RB) from the outputs of R, G, and B as described in the image recording apparatus of Japanese Patent No. 7467 and comparing them with a preset threshold value. ing. Conventionally, in order to solve the above problems,
The threshold for recognizing this color is set to a value that does not cause an erroneous determination even when the vibration is the largest and the reading is most misaligned. However, according to this method, since the threshold value is increased, it is difficult to read the color portion of the document as a color.

The present invention is intended to solve the above-mentioned problems, and does not cause color misjudgment at a specific magnification, and because the threshold for color separation is adjusted to the magnification at which the vibration is the largest, An object of the present invention is to provide a color separation device in which the upper color portion does not become difficult to read.

[0010]

Therefore, according to the present invention, color separation is performed from image information obtained by optically scanning a document by image reading means, and an n-color image is generated based on the separated information. In an image processing apparatus that outputs, or detects a marker color, recognizes a region from the marker color, and outputs an image obtained by editing and processing the image data of the region, a chromatic / achromatic color based on a threshold from image information. It is characterized in that it comprises a determining means for making a determination, a color separating means for determining a hue of a chromatic color and performing color separation, and a setting means for setting the threshold value according to a scanning magnification when scanning a document. is there.

[0011]

In the image processing apparatus of the present invention, the determination means for determining the chromatic color / achromatic color from the image information based on the threshold value, the color separation means for determining the hue of the chromatic color and performing the color separation,
Since the setting means for setting the threshold according to the scanning magnification when scanning the original is provided, by controlling the threshold for color separation according to the scanning magnification to an optimum value, erroneous determination of color at a specific magnification may be prevented. Can be prevented. Further, by adjusting the threshold value to the magnification with the largest vibration, it is possible to prevent the color on the original from becoming difficult to read, and it is possible to carry out n-color copying or marker editing according to the instruction without erroneous determination. .

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an embodiment of an image processing apparatus according to the present invention.

In FIG. 1, the full color sensor 10 is
The CCD line sensor optically scans the original, and the sensor interface circuit 4 generates the timing to be given to the full-color sensor 10, corrects the reading positions of R, G, and B in the sub-scanning direction, and determines the reading position by the magnification. It is for fine adjustment.

The color image information generation circuit 5 obtains a hue from each color data from the sensor interface circuit 4 and performs color separation,
The background density of the marker is converted to 256 pixels
The gradation density information D, the color information, and the closed loop-designated marker color information are generated. As the color information, the main color flag M corresponding to the main color (for example, black)
The CF and the sub-galler flag SCF corresponding to the sub color (for example, red) are generated, and the marker color information is the first A
First AR color flag A corresponding to R color (for example, red)
Second A corresponding to RCF1 and second AR color (eg blue)
The R color flag ARCF2 is generated.

The area recognition circuit 7 outputs marker color information (ARCF1, ARCF) output from the color image information generation circuit 5.
Based on 2), it is determined whether the read pixel is inside or outside the area surrounded by the marker, and the result is output for each pixel. The information of the judgment result here is
First A showing the inside of the area surrounded by the first AR color marker
ARDT1 in the R area, ARDT2 in the second AR area showing the inside of the area surrounded by the markers of the second AR color, and ARDTO outside the area showing the outside of both the first AR area and the second AR area
There are three types.

The correction / filter circuit 6 includes the density information D and the color information color flag SCF from the color image information generation circuit 5.
Various corrections and filter processing such as edge enhancement and smoothing are performed on the MCF.

The editing / processing circuit 8 receives the density information D and the color information color flags SCR and M that have passed through the correction / filter circuit 6.
The CF is subjected to editing / processing such as negative / positive inversion, color inversion, enlargement / reduction, etc. In particular, the determination information ARD from the area recognition circuit 7 is designated by the area designated by the CPU 1.
It has a function of performing a predetermined editing / processing process only on the designated area based on T1, ARDT2, and ARDTO.

The density information D and the color information color flags SCF and MCF which have undergone various processes in the correction / filter circuit 6 and the editing / processing circuit 8 as described above are two colors via the I / O interface circuit 9. It is sent to a specific image forming apparatus such as a laser printer or an image transmitter / receiver for reproduction. It is also sent to a computer and stored in an auxiliary storage device such as a magnetic disk device for use.

The CPU 1 controls each circuit described above and sets parameters such as a table of each circuit. The user interface 2 allows the user to specify the number of output sheets, the copy magnification, and the editing through a control panel, a display, or the like. , Processing designation, operation instruction, and the like.

FIG. 2 is a diagram showing a configuration example of the color image information generating circuit of the present invention, and FIG. 3 is a diagram for explaining the state of saturation / hue by the color separation circuit of the color image information generating circuit of the present invention. is there.
In FIG. 2, the subtraction circuit 11 performs the operation of (RB), and the subtraction circuit 12 performs the operation of (RG). The hue / saturation determination table 14 includes subtraction circuits 11 and 1.
It is a look-up table which inputs the calculation result of 2 and outputs hue H.

Of the calculation outputs from the subtraction circuits 11 and 12, as shown in FIG. 3, (RG) is the vertical axis and (R-G).
When a color space with the horizontal axis of (B) is set, r ² = (R−
G) ² + (R−B) ² and tan θ = (R−
An arbitrary color can be specified by the distance r from the origin 0 and the rotation angle θ which are respectively obtained by G) / (RB). Here, the distance r is a factor that mainly determines the saturation C, and becomes closer to an achromatic color as it approaches the origin. The rotation angle θ is a factor that mainly determines the hue H, such as red, magenta,
Blue, cyan, green, and yellow are distributed at the positions shown in the figure.

Therefore, in the hue / saturation determination table 14, the values of (RB) and (RG) are input to the addresses of the look-up table, and the saturation threshold value and (RB) set in advance are set. ), And the saturation obtained from (RG) are compared, and when the value exceeds the threshold value, it is determined to be a chromatic color, and a code corresponding to the hue is output. If the threshold value is not exceeded, it is determined that the color is achromatic and a code indicating the achromatic color is output.

The hue / saturation determination table 14 is stored in the CPU 1
From the data having a plurality of threshold values stored in advance in the data ROM, the data is selected according to the copy magnification and set in the RAM table. Is to be determined. Since different values are set for the data set in the RAM table as the thresholds for determining the chromatic color / achromatic color depending on the copy magnification, optimum data is selected depending on the scanning magnification.

The selector 13 uses the hue / saturation determination table 14 when rewriting the hue / saturation determination table 14.
Address input from the output of the arithmetic circuits 11 and 12 to the CPU
The address bus AD is switched to one. The hue / saturation determination table 14 is rewritten by the CPU 1 by the control signal ISEL from the hue / saturation determination table 1.
4 is set to the write mode, the selector 13 is switched, an address is designated, and data is written from the data input terminal D1.

The color separation table 16 is a RAM look-up table that can be rewritten by the CPU 1. The color separation table 16 performs color separation of specific colors and markers using the hue H output from the hue / saturation determination table 14 as an address. Color flag MCF, sub color flag SCF, first AR color flag ARCF1, second AR color flag ARCF
It outputs two signals. For example, when the rotation angle θ in the color space shown in FIG. 3 is output from the hue / saturation determination table 14 in steps of 1 °, the color separation table 16 divides 360 ° in steps of 1 °. It is configured to output color separation signals corresponding to the respective addresses.

When rewriting the color separation table 16, the selector 15 switches the address input of the color separation table 16 from the output of the hue / saturation determination table 14 to the output of the CPU 1. To rewrite the color separation table 16, the CPU 1 sets the color separation table 16 in the write mode by the control signal ISEL and the selector 15
Is performed, data is written from the data input terminal D1 by designating an address.

The weight calculation circuit 17 performs weighting by multiplying R, G and B by numerical values such as K _r = 0.3, K _g = 0.6 and K _b = 0.1. The addition circuit 18 adds the signals after weighting R, G, and B to generate and output the density information D.

As described above, data having an optimum threshold value according to the scanning magnification of the scanning device is set in the hue / saturation determination table 14 to determine the hue / saturation, and the hue output as the determination result is addressed. Since color separation can be performed by the rewritable color separation table 16, it is possible to prevent an achromatic color from being erroneously determined to be a chromatic color at a location where the color shift at a specific magnification is large, and the normal color shift is small. It is possible to reliably determine the color even at the magnification.

The present invention is not limited to the above embodiment, but various modifications can be made. For example, in the above embodiment, the description has been made on the assumption that a full color sensor is used, but the color separation may be performed using a sensor having sensitivity in two specific wavelength regions.

[0030]

As is apparent from the above description, according to the present invention, it is possible to prevent color misjudgment at a specific magnification by controlling the threshold value for color separation according to the scanning magnification to an optimum value. Can be prevented. Moreover, by adjusting the threshold for color separation to the magnification with the largest vibration, it is possible to provide a color separation means that does not make it difficult to read the color portion on the document, and the optimum color can be obtained at any magnification. It becomes possible to carry out separation.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of an image processing apparatus according to the present invention.

FIG. 2 is a diagram showing a configuration example of a color image information generation circuit of the present invention.

FIG. 3 is a diagram for explaining a state of saturation / hue by a color separation circuit of the color image information generation circuit of the present invention.

FIG. 4 is a diagram showing a configuration example of a full-color sensor used for image reading.

[Explanation of symbols]

1 ... CPU, 2 ... User interface, 4 ... Sensor interface, 5 ... Color image information generation circuit, 6 ... Correction / filter circuit, 7 ... Region recognition circuit, 8 ... Editing / processing circuit,
9 ... I / O interface, 10 ... Full color sensor

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H04N 1/38 1/387 1/48 H04N 1/46 A

Claims (1)

[Claims] 1. An image reading unit performs color separation from image information obtained by optically scanning an original, and outputs an n-color image based on the separated information or detects a marker color. Recognize the area from the marker color and edit it to the image data of the area,
In an image processing apparatus for outputting a processed image, a determination unit that determines a chromatic color / achromatic color based on a threshold value from image information, a color separation unit that determines a hue of a chromatic color and performs color separation, and an original document. An image processing apparatus, comprising: a setting unit that sets the threshold value according to a scanning magnification when scanning.