JPS6340491A - Color balance adjusting method - Google Patents

Abstract

PURPOSE:To automatically adjust a color balance according to respective pictures by removing only the quantity of the color component of a picture element applying a maximum brightness in a picture from the color components of all the picture elements and adjusting the color balance of the picture for every picture. CONSTITUTION:The luminance signal Y of all the picture elements is extracted, and the picture element in which the Y is a maximum value. The color difference signals R-Y, B-Y of the obtained picture element are obtained and the values are defined to be RY, BY. The RY, BY are the quantities of correcting the color balance and stored in a correction signal memory 40. When picture data is read sequentially read from a claim memory 10, in correction circuits 50R, 50B, the R-Y signal is subtracted by RY and the B-Y signal is subtracted by BY to obtain a color balance corrected color difference signal.

Description

[Detailed description of the invention] Technical fields> The present invention relates to a method for adjusting color balance of a color image.

<Prior Art> Conventionally, this type of method has had the drawback of being cumbersome to operate because it has been necessary to measure white as a standard in addition to the actual image.

<Objective> The present invention eliminates the above-mentioned drawbacks and makes it possible to automatically adjust the color balance according to each image.

More specifically, by visually treating the brightest part of the screen as white, a specific color component does not appear in the maximum brightness pixel, and by reducing the color component of all pixels, the color balance of the screen can be improved. The purpose is to provide a method for adjusting color balance.

<Example> FIG. 1 is an image processing circuit diagram on the tree seed layer side.

In the figure, human color image data includes color signals R, G,
It is stored in the claim memory IOR, 10C 110B for each B. 20 is an encoder matrix that obtains the luminance signal Y1 color difference signal (RY), (B-Y) from R, G, and B;
30 is an arithmetic unit consisting of a microcomputer, etc.
Calculate the color balance correction amount. 40 is a correction signal memory for storing correction amounts; 50R and 50B are color difference signals R-Y.

This is a correction circuit that corrects B-Y.

The control operation of the arithmetic unit 30 will be explained below with reference to the flowchart of FIG.

First, in step S1, the luminance No. 43 Y of all pixels is extracted, and Y
The pixel at which the maximum value is determined is determined at 82. RY and BY of the pixel obtained in step S3 are obtained, and the values are set as RY and BY. RY and BY are color balance correction amounts and are stored in the correction signal memory 40.

This (aRY, BY are 11.f and correction circuits 50R, 50 which read image data sequentially from the claim memory 10.
At B, the RY signal is reduced to RY, and the B-Y signal is reduced to BY, and a color difference signal is obtained as a color balance corrected signal Jl.

<Other Embodiments> RY and B-Y are used as color difference signals, or whatever the saturation is. In addition, although I used the brightness value Yp, it is possible to change the brightness to whatever the brightness is.

I did it with the software, but it doesn't work even if I go to bar 1.

Effect> As described above, according to the final method, it is possible to adjust the color balance for each screen without using the standard white.

[Brief explanation of drawings]

FIG. 1 is a processing circuit diagram of this embodiment, and FIG. 2 is a flowchart of processing operations of the arithmetic unit 30 of FIG. 1.

Claims (1)

[Claims] A color balance adjustment method characterized by adjusting the color balance of a screen for each screen by removing from the color components of all pixels only the color component amount of a pixel that gives maximum brightness on the screen.