JPH04192968A - Color image processor - Google Patents

Abstract

PURPOSE:To automatically execute good color correction by controlling color correction processing according to the color images inputted from electronic equipment. CONSTITUTION:A CPU 2 makes inference as to the kinds of the images stored into an image memory 1 in accordance with the program stored in a ROM 4 and fuzzy argument rule and sets the parameter of a color correction processing circuit 5 according to the discriminated kinds when various kinds of color images are taken into the memory 1 from a computer. The color correction processing meeting the kinds of the color images is executed in this way even with the once stored color images by such constitution. The good color correction is thus automatically executed without the aid of manpower.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color image processing apparatus that automatically changes processing depending on the type of color image.

[Prior art] A conventional color image processing device is, for example, disclosed in Japanese Patent Application Laid-Open No. 61-296.
As disclosed in Japanese Patent No. 858, one set of color correction functions is specified for a color image.

[Problems to be Solved by the Invention] However, in the conventional example described above, it is possible to know in advance which input device the input color image was inputted from, but it is necessary to store the input color image in the computer and then send it to the color image processing device. In such cases, it is unclear what type of image it is. For example, the type of image is
There are a wide variety of images, including CG (computer graphics), input images from image readers, input images from video cameras and Sv (still video) cameras, input images from film scanners, and composite images by remote sensing. Therefore, if the type of image is unknown, the user cannot decide which color correction process to select.

SUMMARY OF THE INVENTION An object of the present invention is to provide a color image processing apparatus that can perform color correction processing suitable for the type of color image even if the color image is once stored.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a color image processing device for processing color image data input from an electronic device for use in a color recording device. The present invention is characterized by comprising a determining means for determining the type of color image to be processed, and a means for controlling color correction processing according to the determined type.

[Embodiment] FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. In FIG. 1, 1 is an image memory that stores image data input from an electronic device, such as a computer, and 2 is a color correction processing circuit that controls each part of the circuit and is based on a program stored in ROM 4 and fuzzy inference rules. A CPU determines the parameters, 3 is a RAM for the work of the CPU 2, and 5 is a color correction processing circuit that performs color correction processing based on parameters for the color correction processing circuit from the CPU 2. The output of the processing circuit 5 is a color image. Output to the processing device.

Next, the operation of this embodiment will be explained using the flowchart shown in FIG.

First, various types of color images are imported from the computer into the image memory l as, for example, RGB signals (
510). Next, the CPU 2 samples N RGB signals from the image memory using the RAM 3 and ROM 4 (513, 515) (FIG. 5). If the maximum value of each of the N sampled RGB signals is set to 1 and the minimum value is set to 0, it can be spread to the coordinates of the cube color space shown in Figure 2, so the cube in Figure 2 can be Several areas, for example, divided areas as shown in FIG. 3, are stored in the ROM 3 in advance.

Although FIG. 3 shows the cubic RG flaw signal plane of FIG. 2, the cube is actually divided three-dimensionally. And C.P.
U2 counts how many RGB signals of N are included in the divided color area or the number of colors (517).

The counted result is stored in RAM4.

Next, perform fuzzy inference based on these data (5
19).

In this embodiment, the type of image stored in the memory l is inferred by creating a histogram for each of the divided color spaces as described above. The following are prepared as examples of fuzzy inference rules in this embodiment (.

■Images with a small number of colors are CG (computer galaxies).

(2) The image with a large area f in FIG. 3 is also CG.

(2) The image in FIG. 3 in which the area C is large and the area d is small is an image from an image reader.

■The area b in FIG. 3 is large (the image with a small area f is an image taken by a video camera or the SV left camera).

FIG. 4 i) to iv) are diagrams showing the membership functions of the number of objects or the number of colors in each area, and
Put it in. The above rule (■) will be explained as an example.

When all of the N sampled signals have different values and do not have the same coordinates, the number of colors is N. However, in images such as computer images, the number of colors is relatively small (the number of colors is 10). Therefore, if you apply Rule 1, the membership function for "images with a small number of colors" If you use the function "few" in (iv) in Figure 4, the output value will be 1.Other rules Based on (membership function (i) in Figure 4) ii) In 1ii), since the membership function is set in advance so that the output does not become 1 in such a case, rule (2) that this image is a type of CG holds true.

As a result, the parameters of the color correction processing circuit 5 are set for CG. For example, a parameter that improves the saturation of a color is set as such a parameter.

When the settings are completed, the corrected image signal is sent from the image memory to the color image recording device.

Note that rules other than I are executed, and if the rule with the largest value is established as a result of the conditional part of the rule, CP
U2 is preprogrammed to make the decision. Also, if there are rules that have the same value, determine the priority order in advance.

An example of the color correction circuit 5 shown in FIG. 2 is shown in FIG.

In FIG. 6, 20 is a RAM for luminance density conversion, and 22 is a hardware circuit for performing masking and UCR. Methods for changing the parameters include changing the brightness density conversion table and changing the masking and UCR coefficients.

[Other Embodiments] Instead of configuring the color correction processing circuit from two circuits as shown in FIG. It is also possible.

Furthermore, even if the image is input to this image processing device from a video camera or film scanner other than through a computer input, it can be automatically discriminated and a good output image can be obtained.

In addition, the area shown in Figure 3 can be further divided into smaller areas, and the area shown in Figure 4 can be further divided.
It is also possible to increase the types of images that can be distinguished by increasing the membership function of the diagram.

As explained above, in this embodiment, the type of image can be determined by performing fuzzy inference on an image imported from a computer using arithmetic means, and the parameters of the color correction processing circuit can be set based on the results. This has the effect of making it possible to output a good image without giving it an unrecognizable appearance.

[Effects of the Invention] As explained above, according to the present invention, color correction processing is controlled according to a color image input from an electronic device, so that good colors can be automatically produced without any manual intervention. Corrections can be made.

[Brief explanation of the drawing]

Fig. 1 is a circuit block diagram of an embodiment of the present invention, Fig. 2 is an explanatory diagram showing the color space, Fig. 3 is a diagram showing the RG plane of the color space of Fig. 2, and Fig. 4 is a diagram showing the color space of the present invention. FIG. 5 is a diagram illustrating the sampling state of RGB signals; FIG. 6 is a diagram showing the membership function of an embodiment of the present invention; FIG.
・Color correction processing circuit length AI-120

Claims (3)

[Claims] (1) A color image processing device that processes color image data input from an electronic device for use in a color recording device,
A color image processing apparatus comprising: a determining means for determining the type of color image input from the electronic device; and a means for controlling color correction processing according to the determined type. (2) The color image processing apparatus according to claim 1, wherein the determining means is a means for sampling image data once stored in a storage device and determining color distribution. (3) The color image processing apparatus according to claim 1, wherein the determining means is a means for determining whether the type of input color image is computer graphics.