Multi-area white-balance control device, multi-area white-balance control method, multi-area white-balance control program, computer in which multi-area white-balance control program is recorded, multi-area white-balance image-processing device, multi-area white-balance image-processing method, multi-area white-balance image-processing program, computer in which multi-area white-balance image-processing program is recorded, and image-capture apparatus

Patent metadata

Field	Value
Publication number	US-2016269707-A1
Application number	US-201615164438-A
Country	US
Kind code	A1
Filing date	May 25, 2016
Priority date	Nov 28, 2013
Publication date	Sep 15, 2016
Grant date	—

Abstract

A multi-area white-balance control device includes a component that divides an inputted image into a plurality of division areas, a component that estimates a lighting-source color temperature for each division area, a component that calculates out color information of an areal image for each division area, and a component that acquires information for white-balance processing on the basis of the lighting-source color temperature and the color information of the areal image for each division in such a manner as to weight, in the information for white-balance processing, a multi-area white-balance factor as more significant in reference to a single-area white-balance factor in a case where the color information has a value higher than a predetermined value, than in a case where the color information fails to have the predetermined value. Thereby, an image with natural color reproduction can be generated.

First claim

What is claimed is:

1 . A multi-area white-balance control device comprising:
an area divider that divides an inputted image into a plurality of division areas; a lighting-source color-temperature estimator that estimates a lighting-source color temperature in each of the division areas; an areal-image color-information calculator that calculates out color information of an areal image for each of the division areas; and a white-balance controller that acquires information for white-balance processing for each of the division areas on a basis of the lighting-source color temperature in each of the division areas estimated by the lighting-source color-temperature estimator and the color information of the areal image for each of the division areas calculated out by the areal-image color-information calculator; wherein, in acquiring the information for white-balance processing for each of the division areas, the white-balance controller considers at least one of a multi-area white-balance factor and a single-area white-balance factor in such a manner that the multi-area white-balance factor is weighted as more significant in a case where the color information of the areal image for each of the division areas has a value higher than a predetermined value, than in a case where the color information of the areal image for each of the division areas fails to have a value higher than the predetermined value.

2 . The multi-area white-balance control device according to claim 1 ,
wherein the information for white-balance processing for each of the division areas includes a white-balance coefficient for each of the division areas, wherein the white-balance controller comprises:
a multi-area white-balance coefficient generator that generates a multi-area white-balance coefficient for each of the division areas on a basis of the lighting-source color temperature in each of the division areas estimated by the lighting-source color-temperature estimator;
a single-area white-balance coefficient generator that generates a single-area white-balance coefficient; and
a white-balance coefficient synthesizer that calculates out the white-balance coefficient for each of the division areas by synthesizing the multi-area white-balance coefficient for each of the division areas and the single-area white-balance coefficient, and
wherein, in calculating out the white-balance coefficient for each of the division areas, the white-balance coefficient synthesizer synthesizes the multi-area white-balance coefficient for each of the division areas and the single-area white-balance coefficient in such a manner that a component ratio of the multi-area white-balance coefficient increases according as a value of the color information of the areal image for each of the division areas increases.

3 . The multi-area white-balance control device according to claim 1 ,
wherein the information for white-balance processing for each of the division areas includes a white-balance coefficient for each of the division areas, wherein the lighting-source color-temperature estimator further estimates a lighting-source color temperature in a single area as an entirety of the inputted image, on a basis of the lighting-source color temperatures in the individual division areas as estimated, wherein the white-balance controller comprises:
a color-temperature synthesizer that synthesizes the lighting-source color temperature in each of the division areas and the lighting-source color temperature in the single area estimated by the lighting-source color-temperature estimator, to calculate out an adjusted lighting-source color temperature in each of the division areas; and
a white-balance coefficient generator that generates the white-balance coefficient for each of the division areas on a basis of the adjusted lighting-source color temperature in each of the division areas calculated out by the color-temperature synthesizer; and
wherein, in calculating out the adjusted lighting-source color temperature in each of the division areas, the color-temperature synthesizer synthesizes the lighting-source color temperature in each of the division areas and the lighting-source color temperature in the single area estimated by the lighting-source color-temperature estimator in such a manner that a component ratio of the lighting-source color-temperature in each of the division areas estimated by the lighting-source color-temperature estimator increases according as a value of the color information of the areal image for each of the division areas calculated out by the areal-image color-information calculator increases.

4 . The multi-area white-balance control device according to claim 1 ,
wherein the information for white-balance processing for each of the division areas includes a white-balance gain map for each of the division areas, wherein the white-balance controller comprises:
a multi-area white-balance gain map generator that generates a multi-area white-balance gain map for each of the division areas on a basis of the lighting-source color temperature in each of the division areas estimated by the lighting-source color-temperature estimator;
a single-area white-balance gain map generator that generates a single-area white-balance gain map; and
a white-balance gain map synthesizer that calculates out the white-balance gain map for each of the division areas by synthesizing the multi-area white-balance gain map for each of the division areas and the single-area white-balance gain map, and
wherein, in calculating out the white-balance gain map for each of the division areas, the white-balance gain map synthesizer synthesizes the multi-area white-balance gain map for each of the division areas and the single-area white-balance gain map in such a manner that a component ratio of the multi-area white-balance gain map increases according as a value of the color information of the areal image for each of the division areas increases.

5 . The multi-area white-balance control device according to claim 1 ,
wherein the information for white-balance processing for each of the division areas includes a white-balance gain map for each of the division areas, wherein the lighting-source color-temperature estimator further estimates a lighting-source color temperature in a single area as an entirety of the inputted image, on a basis of the lighting-source color temperatures in the individual division areas as estimated, wherein the white-balance controller comprises:
a color-temperature synthesizer that synthesizes the lighting-source color temperature in each of the division areas and the lighting-source color temperature in the single area estimated by the lighting-source color-temperature estimator, to calculate out an adjusted lighting-source color temperature in each of the division areas; and
a white-balance gain map generator that generates the white-balance gain map for each of the division areas on a basis of the adjusted lighting-source color temperature in each of the division areas calculated out by the color-temperature synthesizer; and
wherein, in calculating out the adjusted lighting-source color temperature in each of the division areas, the color-temperature synthesizer synthesizes the lighting-source color temperature in each of the division areas and the lighting-source color temperature in the single area estimated by the lighting-source color-temperature estimator in such a manner that a component ratio of the lighting-source color-temperature in each of the division areas estimated by the lighting-source color-temperature estimator increases according as a value of the color information of the areal image for each of the division areas calculated out by the areal-image color-information calculator increases.

6

Assignees

• Olympus Corp

Inventors

• Yoshizaki Kazunori

Classifications

• H04N23/88 Primary

  for colour balance, e.g. white-balance circuits or colour temperature control · CPC title

• H04N23/84 Primary

  for processing colour signals · CPC title

• H04N23/10

  for generating image signals from different wavelengths · CPC title

• H04N9/735 Primary

  Electricity · mapped topic