Information processing device, information processing method, and program to perform calibration with respect to environment light

1. An information processing device, comprising:

a memory configured to store detected values of illuminances of environment light; and

color temperature estimation circuitry configured to estimate a color temperature of the environment light, on a basis of detected values of illuminances of the environment light within a plurality of wavelength bands, wherein

the plurality of wavelength bands of the environment light includes a wavelength band in a visible light region and a wavelength band in a near-infrared light region, and

the color temperature estimation circuitry calculates irradiances of the environment light at a plurality of wavelengths, on a basis of the detected values of the illuminances of the environment light at the plurality of wavelength bands, and estimates the color temperature of the environment light, on a basis of calculated values of the irradiances of the environment light at the plurality of wavelengths.

2. The information processing device according to claim 1 ,

wherein the color temperature estimation circuitry estimates the color temperature of the environment light, by comparing the calculated values of the irradiances of the environment light at the plurality of wavelengths, with defined values of the irradiances of the environment light of each color temperature at the plurality of wavelengths.

3. The information processing device according to claim 1 ,

wherein the plurality of wavelengths of the environment light include a wavelength in the visible light region and a wavelength in the near-infrared light region.

4. The information processing device according to claim 1 ,

wherein the detected values of the illuminances of the environment light within the plurality of wavelength bands are detected by an illuminance sensor.

5. The information processing device according to claim 4 ,

wherein the color temperature estimation circuitry calculates the irradiances of the environment light at the plurality of wavelengths, on a basis of the detected values of the illuminances of the environment light at the plurality of wavelength bands, and spectral characteristics of the illuminance sensor.

6. The information processing device according to claim 5 ,

wherein the illuminance sensor detects the illuminance of the environment light through a diffusion plate, and

the color temperature estimation circuitry calculates the irradiances of the environment light at the plurality of wavelengths, on a further basis of spectral characteristics of the diffusion plate.

7. The information processing device according to claim 1 , further comprising:

spectroscopic analysis circuitry configured to detect spectral characteristics of a reflection rate of a subject that is photographed under the environment light, on a basis of spectral characteristics of the environment light of the estimated color temperature.

8. The information processing device according to claim 7 ,

wherein the spectroscopic analysis circuitry detects the spectral characteristics of the reflection rate of the subject, on a further basis of spectral characteristics of a photographing device that photographs the subject.

9. The information processing device according to claim 7 , further comprising:

evaluation index calculation circuitry configured to calculate an evaluation index that is used for evaluating the subject, on a basis of the reflection rate of the subject.

10. The information processing device according to claim 9 ,

wherein the evaluation index is a normalized difference spectral index (NDSI).

11. The information processing device according to claim 1 , further comprising:

coefficient calculation circuitry configured to calculate a coefficient indicating a ratio between a product of spectral characteristics of a photographing device with respect to a first wavelength and spectral characteristics of the environment light, and a product of spectral characteristics of the photographing device with respect to a second wavelength and the spectral characteristics of the environment light; and

evaluation index calculation circuitry configured to calculate an evaluation index that is used for evaluating a subject in an image photographed by the photographing device, on a basis of a component of the first wavelength and a component of the second wavelength of the image, and the coefficient.

12. The information processing device according to claim 11 ,

wherein the first wavelength is a wavelength of red light,

the second wavelength is a wavelength of near-infrared light, and

the evaluation index is a normalized difference vegetation index (NDVI).

13. The information processing device according to claim 1 ,

wherein the wavelength band in the visible light region is one of a red light region, a blue light region or a green light region.

14. The information processing device according to claim 1 ,

wherein the plurality of wavelength bands of the environment light include a plurality of wavelength bands in visible light regions, the visible light regions respectively being two or more of a red light region, a blue light region or a green light region.

15. An information processing method, comprising:

storing detected values of illuminances of environment light; and

estimating a color temperature of the environment light, on a basis of the detected values of illuminances of the environment light within a plurality of wavelength bands, wherein

the plurality of wavelength bands of the environment light includes a wavelength band in a visible light region and a wavelength band in a near-infrared light region, and

calculating irradiances of the environment light at a plurality of wavelengths, on a basis of the detected values of the illuminances of the environment light at the plurality of wavelength bands, and

estimating the color temperature of the environment light, on a basis of calculated values of the irradiances of the environment light at the plurality of wavelengths.

16. A non-transitory computer readable medium storing program code executable by a processor to perform operations comprising:

storing detected values of illuminances of environment light; and

estimating a color temperature of the environment light, on a basis of the detected values of illuminances of the environment light within a plurality of wavelength bands, wherein

the plurality of wavelength bands of the environment light includes a wavelength band in a visible light region and a wavelength band in a near-infrared light region, and calculating irradiances of the environment light at a plurality of wavelengths, on a basis of the detected values of the illuminances of the environment light at the plurality of wavelength bands, and

estimating the color temperature of the environment light, on a basis of calculated values of the irradiances of the environment light at the plurality of wavelengths.

17. An apparatus comprising:

a processor; and a

memory, the memory storing program code executable by the processor to perform operations comprising:

storing detected values of illuminances of environment light; and

estimating a color temperature of the environment light, on a basis of the detected values of illuminances of the environment light within a plurality of wavelength bands, wherein

the plurality of wavelength bands of the environment light includes a wavelength band in a visible light region and a wavelength band in a near-infrared light region, and

calculating irradiances of the environment light at a plurality of wavelengths, on a basis of the detected values of the illuminances of the environment light at the plurality of wavelength bands, and

estimating the color temperature of the environment light, on a basis of calculated values of the irradiances of the environment light at the plurality of wavelengths.