JPH0316376A - Picture processor - Google Patents

Abstract

PURPOSE:To attain color conversion to a prescribed designated color for a desired conversion area of a color picture of an original while keeping the gradation of the original picture by applying color conversion to a conversion area with a designated color corresponding to the original density of an input picture data when the input picture data exists in the conversion area. CONSTITUTION:A picture processing section 2 connecting to a picture input section 1 is provided with a conversion condition setting means setting a conversion area and a conversion condition of a color picture subject to color conversion, a conversion discrimination means comprising a conversion discrimination circuit discriminating an input picture data to be in the conversion area at picture reading and outputting a permission signal, and a color conversion means comprising a color conversion circuit converting the conversion area into a density corresponding to each of designated colors. Moreover, a picture output section 3 connecting to the picture processing section 2 is provided with picture memory and the picture data subject to color conversion processing by the color conversion means is outputted. Thus, the color conversion to a prescribed color is attained while the gradation of the designation area on an original is kept as it is.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image processing apparatus, and particularly to an image processing apparatus that performs color conversion on a desired area of a color image.

[Conventional technology]

Color image forming devices, such as color copying machines, are required to reproduce colors faithful to the original to form images.
In recent years, there has also been a demand for an apparatus that can convert a predetermined area of a document into a specified color to create an image.

Regarding the technology of color converting a predetermined area of a document, Japanese Patent Laid-Open No. 192863/1983 and Japanese Patent Laid-open No. 62-1928
One disclosed in Japanese Patent No. 192864 is known.

The system disclosed in Japanese Patent Application Laid-Open No. 192863/1983 converts an area of a certain density and tone of a document specified by a position specifying means into a predetermined color to form a color image. Furthermore, Japanese Patent Application Laid-open No. 192864/1986 discloses that an area of a certain density and color tone of a document specified by a position specifying means is
A color image processing device has been disclosed that converts the colors of a document to other hues to form a color image.

By using the techniques disclosed in these publications, it is possible to obtain an image processing apparatus that converts a predetermined area of a document into a specified color to form an image.

[Problem to be solved by the invention]

The color image processing device disclosed in the above-mentioned publication is
In either case, a color image is formed by converting a specified area of a certain density and tone specified by a position specifying means on a document into another color of a certain density.

Depending on the techniques disclosed in these publications, it is not possible to maintain the gradation of a designated area on a document as it is and convert the color to another predetermined color. In this case, it is conceivable to use the RAM as a look-up table to perform color conversion with gradation, but this increases the memory capacity and complicates the device.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image processing apparatus having an IS structure that performs color conversion to a predetermined color while maintaining the gradation of a designated area on a document. [Means for Solving the Problem] The above object is to provide an image reading means for reading a color image, a conversion condition setting means for setting a conversion area for color conversion of the color image and a color conversion condition for the conversion area, and the above-mentioned object. conversion determination means for determining that the input image data is in the conversion area set by the conversion condition setting means and outputting a permission signal when reading the image by the image reading means; This can be achieved by including a color conversion means for converting the color to a specified color.

[For production]

The conversion condition setting means sets a conversion area in which color conversion of a color image is to be performed and desired color conversion conditions for the conversion area. When reading an image, the conversion determining means determines whether the input image data is in the conversion area, and if it is in the conversion area, performs color conversion for the conversion area using a specified color corresponding to the original density of the input image data. I do.

In this way, the conversion area is color-converted while maintaining the gradation of the original image, and a color image in which the original image is reproduced is produced in areas other than the conversion area.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the overall structure of an embodiment of the present invention, in which 2 is an image input section, 2 is an image processing section, and 3 is an image output section.

The image input section 1 is provided with image reading means for reading a color image of a document with an image sensor and outputting color-separated three-color color data (digital data). Color image information is reproduced by mixing three primary colors, but in image systems that use additive color mixing, such as on televisions, the primary colors are red (R), green (G), and blue (B), and in subtractive color mixing, such as in photography and printing. , the primary colors are cyan (C) and magenta (
M), becomes yellow (Y).

The image processing section 2 connected to the image processing section 1 includes a conversion condition setting means for setting the conversion area and conversion conditions of the color image to be subjected to color conversion, and a conversion condition setting means for setting the conversion area and conversion conditions of the color image to be subjected to color conversion. A conversion determining means is provided, which includes a conversion determining circuit that determines the color and outputs a permission signal, and a color converting circuit includes a color converting circuit that converts the conversion area to a density corresponding to each designated color. In addition, the image processing unit 2
The image output section 3 connected to is provided with an image memory,
Image data that has been subjected to color conversion processing by the color conversion means is output.

FIG. 2 is a circuit diagram showing the configuration of a conversion determination circuit in an embodiment of the present invention, and includes circuits 4a, 4b, 4c, 4d, and 4e.
, 4f is a latch, 5a, 5b, 5c, 5d, 5e, 5f
are comparators connected to latches 4a to 4f, respectively, and 6
is an AND circuit connected to comparators 5a to 5f.

If you use a conversion condition setting means (not shown), for example a digitizer, to specify the highest density position of the conversion area on the color image that is the original, when the highest density position is scanned by pre-scanning, the A peripheral image (image data) is stored in a data storage means (not shown), and after scanning, a CPU reads peripheral pixels from the data storage means,
Calculate high concentration data. High concentration data is on CPUBUS
is output to latch 4 by the CPU's write signal LTO.
a, and the output of the laser chip 4a is input to the P terminal of the comparator 5a.

Furthermore, when the lowest density position of the conversion area is specified by the conversion condition setting means and the lowest density position is scanned by Blisscan, the low density data corresponding to yellow (Y) (or blue B) is sent to the CPU's write signal. The signal is input to the laser chip 4b by the LTI, and then input to the Q terminal of the comparator 5b. Similarly, magenta (M) (
High-density data corresponding to magenta (M) (or blue (
The low density data corresponding to B)) is the CPU write signal L.
The signal is inputted to the latch 4d by T3, and then to the Q terminal of the comparator 5d.

In exactly the same way, cyan (C) (or red (R))
The high density data corresponding to cyan (C) (or red (R)) is input to the laser chip 4e by the CPU's write signal LT4, and the low density data corresponding to cyan (C) (or red (R)) is input to the P terminal of the comparator 5e by the CPU's write signal LT4. Lunch 4f by LT5
, and is input to the Q terminal of the comparator 5f. During actual scanning, when input image data corresponding to yellow (Y) (or blue (B)) is input to the Q terminal of the comparator 5a and the P terminal of the comparator 5b, the input image data is output from the comparator 5a. An output occurs when the concentration of is less than the high concentration data. Similarly, the comparator 5b is configured to produce an output when the density of the input image data is greater than the low density data. Therefore, when the density of the input image data is greater than the low density data and smaller than the high density data, the logic values of the signals at the output terminals of the comparators 5a and 5b are both "1".

The input image data circuit corresponding to magenta (M) (or green (G)) is also cyan (C) (or red (R)).
Since the circuit for the input image data corresponding to A is constructed in exactly the same way, when the density of the three primary colors is between the maximum density ε and the minimum density specified by the conversion condition setting means, A
The ND circuit 6 is configured to output an enable signal EN. FIG. 3 is a horizontal circuit diagram of a color conversion circuit according to an embodiment of the present invention, in which (a), (b), and (c) are yellow (or blue (B)) and magenta (M ) (
or green (G)), cyan (C) (or red (R)
)) is a color conversion circuit corresponding to

In Fig. 3(a), Fig. 3(b) and Fig. 3(C), 7a, 7b, 7c are latches, 3a, 8b, 8c are arithmetic units, 9a, 9b, 9c are selectors, 10a, 10b ，
10c is a selector, lla. 1lb, llc are OR circuits, 12a, 12b . 12c is an AND circuit.

As shown in FIG. 3(a), the designated color data LT6 is input to the latch 7a, and the output terminal of the latch 7a and the yellow (
The input terminal of the input image data corresponding to Y) (or blue (B)) is connected to the input terminal of the arithmetic unit 8a, and the output terminal of the arithmetic unit 8a and the input terminal of the input image data are connected to the input terminal of the selector 9a. connected to the terminal. The connection terminal of the selector 9a and the output terminal of the latch 7a are connected to the input terminal of the selector 10a, and the output terminal of the conversion judgment circuit 4 shown in FIG. ND circuit 1
The output terminal of an EXOR circuit 11a, which is connected to the selector 10a via the EXOR circuit 2a and has input terminals connected to the laser chip 7a and the arithmetic unit 8a, is connected to the manual terminal of the AND circuit 12a.

A color conversion circuit having the same structure as the color conversion circuit shown in FIG. 3(a) described above is shown in FIG. 3(b). As shown in (c), it is also provided for input image data of the other three primary colors.

Next, the operation of the above structure will be explained.

A conversion condition setting means, for example, a digitizer, is used to capture the highest density image data and the lowest density image data of the hue from the conversion area on which color conversion is to be performed on a color image serving as a document, and then perform color separation. High-density data, which is yellow (Y) (or blue (B)) image data with the highest density, is loaded into the cassette 4a by the write signal LTO, and low-density data, which is the lowest density image data, is latched by the write signal LTI. It is inserted into 4b.

Similarly, magenta (M) (or green (G)) high-density data and low-density data are input to latch 4c and latch 4d, respectively, and cyan (C) (or red (R)) high-density data and low-density data are loaded into the launch 4d and latch 4f, respectively.Next, in the same way, the digitizer of the conversion condition setting means captures designated color data from the color image of the original or from another color image. , the color-separated designated color data of the three primary colors are respectively input to the laser chips 7a, 7b, and 7C.

This state means that the image output section 3 is stopped and prescanning is performed only by the image input section 1 and the image processing section 2.

Next, when an actual scan is performed, the input image data input to the conversion judgment circuit 4 shown in FIG.
It is input to the Q terminal of a and the P terminal of the comparator 5b. Therefore, if the density of the yellow (Y) (or blue (B)) image data is between the minimum and maximum image data density of the conversion area, the logic value of the signal at the output terminals of the comparators 5a and 5b becomes “1”. Similarly, magenta (
M) (or green (G)) When the density of the image data is between the minimum image data density and the maximum image data density in the conversion area, the logical values of the signals at the output terminals of the comparators 5c and 5d become "1". So, cyan (C) (or red (R))
When the density of the image data is between the minimum image data density and the maximum image data density in the conversion area, the logical values of the signals at the output terminals of the comparators 5e and 5r become "1". In this way, when it is determined that the input image data is within the density range of the conversion area for the three primary colors, the conversion determination circuit 4 outputs the permission signal EN.

During actual scanning, yellow (Y) (or blue (B)) image data is input to the color conversion circuit 5 in FIG. 3(a), but if the permission signal EN is not output from the conversion determination circuit 4, Selectors 9a and 10a do not perform selector operation,
The yellow (Y) (or blue (B)) image data is directly output from the output terminal of the selector 10a via the selector 9a.

When the conversion area is scanned and the enable signal EN is output, this enable signal EN is sent to the selector 9a and the AND circuit 12a.
is input to the selector 10a via the selector 9a, 1
0a performs a select operation.

For this purpose, the specified color data LT output from the Lasochi 7a
6, the calculator 8a selects yellow (Y) (or blue (B)
)) Specified color image data that has been subjected to density processing according to the image data is selectively inputted from the arithmetic unit 8a by the selector 9a, and this specified color image data is output from the output terminal of the selector 10a. In this manner, the color conversion circuit 5 of FIG. 3(a) performs color conversion processing on yellow (Y) (or blue (B)) image data. Similarly, the color conversion circuits 5 in FIGS. 3(b) and 3(c) convert magenta (M) (or green (G)) image data and cyan (C) (or red (R)) image data, respectively. Color conversion processing is performed.

Therefore, the original input image data is output to the output terminals of the selectors lOa, IO'b, and 10c for the area outside the conversion area, and the specified color image data is output for the area inside the conversion area. Especially in the case of an overflow state, , selector 10a. 10
b. 10c, arithmetic units 8a, 8b . When 8c is adding, everything is in the highest density output state, and when subtracting, everything is in the zero output state. In the density processing by the computing units 8a, 8b, and 8c, at least one of the maximum density and minimum density of the obtained specified color image data can be increased or decreased with respect to the input image data. In this way, the output of the color conversion circuit 5 is supplied to the image output unit 3, and the image output unit 3 uses additive color mixing or subtractive color mixing to transform the converted area of the color image of the original into a color image that maintains the gradation of the original image. The converted image is displayed.

As described above, according to this embodiment, it is possible to form an image obtained by color-converting a desired conversion area of a color image of a document while maintaining the original gradation with a simple circuit configuration.

Setting the conversion area and importing designated color data are performed by specifying the density of a predetermined hue on a color image of a document or another color image, so that operations are simple and quick. Also, since I'm not using a lookup table,
The manufacturing cost of the device is also reduced.

[Effects of the Invention] As is clear from the above description, according to the present invention configured as described above, a desired conversion area of a color image of a document can be converted into an original image with a simple and low cost structure. It is possible to provide an image processing device that can form, with a simple operation, a color image whose color is converted to a predetermined specified color while maintaining the gradation of the image.

[Brief explanation of the drawing]

Figures 1 to 3 show the structure of an embodiment of the present invention. Figure 1 is a block diagram showing the overall structure, Figure 2 is a circuit diagram of a conversion judgment circuit, and Figure 3 is a color diagram. FIG. 3 is a circuit diagram of a conversion circuit. 1... Image input section, 2... Image processing section, 3... Image output section, 4a, 4b, 4c, 4d
, 4e. 4f...Latch, 5a, 5b, 5c,
5d, 5e, 5f... Comparator, 6...
A N D' circuit 7a, 7b 7c...Latch, 8a, 8b, 8c... Arithmetic unit, 9 a,
9 b, 9 c---Selector, 10a,
10bC...Selekuku.

Claims (1)

[Claims] an image reading means for reading a color image; a conversion condition setting means for setting a conversion area for performing color conversion of the color image and a color conversion condition for the conversion area; The conversion determining means determines that the image is in the conversion area set by the condition setting means and outputs a permission signal, and the color converting means converts the conversion area into a designated color with a density corresponding to the original image. An image processing device characterized by: