JPH02155389A - Color difference correction device - Google Patents

Abstract

PURPOSE:To correct a color difference without needing the analysis of the structure and characteristic of a picture input device by obtaining a correction value of an output of a picture input means, correcting an original picture to be displayed with the correction value by the picture input means and giving the result to a picture display means. CONSTITUTION:A light dimmer of a 3 primary colors light is adjusted so that a white color diffusion reflecting plane X and a color index Y within a prescribed visual field are equal in color and a 3 primary colors value is obtained from the reading of the light dimmer, and the 3 primary colors value is stored in a photometry memory 4. Then the color index Y is inputted by a picture input means 1, an RGB value is obtained via a changeover means 2 and stored in the photometry memory 4. A correction value generating means 5, based on the content of the memory 4, calculates mathematically a correction matrix so that the value obtained by a photometric means 3 and the value obtained by the picture input means 1 are made equal to the utmost in the LUV space. A correction means 7 inputs the RGB value via the changeover means 2, multiples the correction matrix with the value and the result is given to a picture display means 8, in which the result is displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is applied to a color difference correction device for digital image processing. In particular, it relates to a method of inputting a color image from an image input device such as a camera and displaying it on a display in the same way as the original image.

〔overview〕

The present invention provides a color difference correction device that compares the colorimetric amounts of a means for measuring color using a plurality of mutually different color targets and an image input means, obtains a correction value for the output of the image input means, and inputs an original image to be displayed by the image input means. By correcting the image using this correction value and applying it to the image display means, it is possible to correct the color difference without having to analyze the structure and characteristics of the image input device and without being aware of it.

[Conventional technology]

Conventionally, color difference correction devices have used different color difference correction methods for each device depending on characteristics such as the structure of the image input device and its sensor sensitivity.

[Problem that the invention seeks to solve]

However, such conventional color difference correction devices have the disadvantage that correction cannot be performed unless the structure and characteristics of the image input device are clarified because the correction is performed by analyzing the structure and characteristics of the image input device.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks, and aims to provide a color difference correction device that can correct color differences without having to analyze the structure and characteristics of an image input device.

[Means for solving problems]

The present invention provides a color difference correction device comprising an image input means for inputting an original image and outputting a colorimetric amount of the original image, and an image display means for inputting the colorimetric amount of the original image and displaying a color image.
a means for colorimetrically measuring a color target, a colorimetric amount memory in which the outputs of the colorimetric means and the image input means for a plurality of mutually different color targets are stored; means for creating a correction amount for the output of the input device; a correction value memory in which the output of the creating means is stored; a correction means for providing a color quantity, and when the image input means inputs a color target, the output thereof is given to the colorimetric amount memory, and when the image input means inputs an original image to be displayed, the output is sent to the correction means. The invention is characterized by comprising a switching means for giving.

[Effect]

Colorimetry is performed using a colorimetric means and an image input means for a plurality of mutually different color targets, and the results are stored in a colorimetric amount memory. The creating means creates a correction value from the output of the image input means based on the colorimetric amount memory and stores it in the correction value memory. The correction means corrects the output of the image input means based on the contents of the correction value memory, and provides the corrected image to the image display means as a colorimetric amount of the original image. The switching means applies the output to the colorimetric amount memory when the image input means is a color target, and gives the output to the correction means when the image input means is an original image to be displayed. By the above-described operation, there is no need to analyze the structure and characteristics of the image input colorimetric quantity, and color difference correction can be performed without being conscious of it.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings. 1st
The figure is a block diagram of a color difference correction device according to an embodiment of the present invention. In FIG. 1, the color difference correction device includes an image input means 1 for inputting an original image and outputting the colorimetric amount of the original image, and an image display means 8 for inputting the colorimetric amount of the original image and displaying a color image. .

Here, the features of the present invention include a colorimetric means 3 as a means for colorimetrically measuring a color target, and a colorimetric quantity in which the outputs of the colorimeter 3 and image input means 1 for a plurality of mutually different color targets are stored. a memory 4, a correction value creation means 5 as means for creating a correction amount for the output of the image input means 1 based on the contents of the colorimetric amount memory 4, and a correction value memory 6 in which the output of the correction value creation means 5 is stored. and a correction means 7 which corrects the output of the image input means 1 based on the contents of the correction value memory 6 and provides it as a colorimetric amount of the original image, and when the image input means 1 inputs a color target, the output is used as a colorimetric amount. When the image input means 1 inputs an original image to be displayed to the memory 4, the image input means 1 is provided with a switching means 2 for applying the output to the correction means 7.

The operation of the color difference correction device having such a configuration will be explained. FIG. 2 is an explanatory diagram of the color measuring means of the color difference correction device of the present invention. In FIG. 2, X is a white diffuse reflection surface, Y is a color standard, R, G, and B are three primary color lights, and F is a standard light. Adjust the intensity of the three primary color lights RXG and B using dimmers and observe them with an observation telescope. Adjust the dimmer of the three primary colors so that the white diffuse reflection surface X and the color mark Y within the defined field of view are the same color, and calculate the three primary color values (RGB values, RED-) from the dimmer readings.
GREEN-BLUE value). The three primary color values are stored in the colorimetric amount memory 4. Next, the color target Y is input to the image input means 1.
The RGB values are input via the switching means 2 and stored in the colorimetric amount memory 4.

The above operations are performed for a plurality of color targets to obtain each RGB value.

The correction value creation means 5 calculates the values obtained by the colorimetry means 3 and the values obtained by the image input means 1 based on the contents of the colorimetry amount memory 4 into a LUV space (CIE (Commission Internationale de l'Eclairage) 1).
976 Recommendation LUV color space] is calculated mathematically by IJ Fuchs.

The correcting means 7 inputs the RGB values of the natural color image obtained by the image inputting means 1 via the switching means 2, multiplies the RGB values by a correction method and IJ hook, and provides them to the image display means 8 for display.

〔Effect of the invention〕

As described above, the present invention has an excellent effect in that it is not necessary to analyze the structure of the image input device and its characteristics, and color difference can be corrected without being consciously aware of it.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a color difference correction device according to an embodiment of the present invention. FIG. 2 is an explanatory diagram of the color measuring means of the color difference correction device of the present invention. DESCRIPTION OF SYMBOLS 1... Image input means, 2... Switching means, 3... Colorimetric means, 4... Colorimetric amount memory, 5... Correction value creation means, 6... Correction value memory, 7 ...Correction means, 8...
- Image display means, F...standard light, X...white diffuse reflection surface, Y...color mark.

Claims (1)

[Claims] 1. A color difference correction device comprising an image input means for inputting an original image and outputting the colorimetric amount of the original image, and an image display means for inputting the colorimetric amount of the original image and displaying a color image. means for colorimetrically measuring a color target; a colorimetric quantity memory in which the outputs of the colorimetric unit and the image input means for a plurality of mutually different color targets are stored; and a colorimetric quantity memory based on the contents of the colorimetric quantity memory. means for creating a correction amount for the output of the image input device; a correction value memory in which the output of the creation means is stored; When the image input means inputs a color target, the output is applied to the colorimetric amount memory, and when the image input means inputs an original image to be displayed, the output is corrected as the colorimetric amount. 1. A color difference correction device comprising: switching means for changing the color difference to the color difference correction device.