Video signal processing apparatus and method with infrared component remover

1. A video signal processing apparatus, comprising:

an image sensor and an infrared component remover,

the image sensor receiving light through a color filter, the color filter including long-pass filters only or a combination of a long-pass filter and an all-transmissive filter, the long-pass filters including a visible-light transmissive long-pass filter for permitting a visible-light component and an infrared-light component to pass therethrough and an infrared-light transmissive long-pass filter for permitting an infrared-light component to pass selectively therethrough, and

the infrared-light component remover removing an infrared-light component contained in a signal having passed through the visible-light transmissive long-pass filter, with transmittance data of an infrared-light region of the visible-light transmissive long-pass filter and the infrared-light transmissive long-pass filter applied.

2. The video signal processing apparatus according to claim 1 , wherein the infrared-light component remover calculates a parameter that reduces to approximately zero the infrared-light component contained in the signal having passed through the visible-light transmissive long-pass filter, with the transmittance data of the infrared-light region of the visible-light transmissive long-pass filter and the infrared-light transmissive long-pass filter applied, and

generates, with the calculated parameter applied, a color signal being a visible-light component that is obtained by removing the infrared-light component from the signal having passed through the visible-light transmissive long-pass filter.

3. The video signal processing apparatus according to claim 1 , wherein each of the visible-light transmissive long-pass filter and the infrared-light transmissive long-pass filter, forming the color filter, has a substantially constant transmittance in the infrared-light region.

4. The video signal processing apparatus according to claim 1 , wherein the color filter comprises:

a long-pass filter for permitting light in a visible-light region and an infrared-light region to pass therethrough with only an ultraviolet-light component cut off;

a long-pass filter for permitting light in the visible-light region equal to or longer than a yellow light wavelength and the infrared-light region to pass therethrough;

a long-pass filter for permitting light in the visible-light region equal to or longer than a red light wavelength and the infrared-light region to pass therethrough; and

an infrared-light transmissive long-pass filter for permitting light mainly in the infrared-light region to pass therethrough.

5. The video signal processing apparatus according to claim 1 , wherein the color filter comprises:

an all-transmissive filter for permitting light in a visible-light region and an infrared-light region to pass therethrough;

a long-pass filter for permitting light in the visible-light region equal to or longer than a yellow light wavelength and the infrared-light region to pass therethrough;

a long-pass filter for permitting light in the visible-light region equal to or longer than a red light wavelength and the infrared-light region to pass therethrough; and

an infrared-light transmissive long-pass filter for permitting light mainly in the infrared-light region to pass therethrough.

6. The video signal processing apparatus according to claim 1 , further comprising a demosaic processor for demosaicing a mosaic image output from the image sensor,

wherein the infrared-light component remover receives demosaic data generated by the demosaic processor and generates for each pixel a color signal containing a visible-light component with the infrared-light component removed therefrom.

7. The video signal processing apparatus according to claim 1 , further comprising an interpolator for generating an image containing a visible-light component and an infrared-light component by interpolating a mosaic image generated from transmission data of the visible-light transmissive long-pass filter contained in the color filter.

8. The video signal processing apparatus according to claim 1 , further comprising a decoder for generating infrared-light communication data by decoding a mosaic image generated from transmission data of the infrared-light transmissive long-pass filter contained in the color filter.

9. An image sensor for receiving light through a color filter, the color filter comprising long-pass filters only or a combination of a long-pass filter and an all-transmissive filter, the long-pass filters including a visible-light transmissive long-pass filter for permitting a visible-light component and an infrared-light component to pass therethrough and an infrared-light transmissive long-pass filter for permitting an infrared-light component to pass selectively therethrough; and

wherein, when a signal has passed through the visible-light transmissive long-pass filter, an infrared-light component is configured to be removed therefrom, with transmittance data of an infrared-light region of the visible-light transmissive long-pass filter and the infrared-light transmissive long-pass filter applied.

10. The image sensor according to claim 9 , wherein each of the visible-light transmissive long-pass filter and the infrared-light transmissive long-pass filter, forming the color filter, has a substantially constant transmittance in the infrared-light region.

11. The image sensor according to claim 9 , wherein the color filter comprises:

a long-pass filter for permitting light in a visible-light region and an infrared-light region to pass therethrough with only an ultraviolet-light component cut off;

a long-pass filter for permitting light in the visible-light region equal to or longer than a yellow light wavelength and the infrared-light region to pass therethrough;

a long-pass filter for permitting light in the visible-light region equal to or longer than a red light wavelength and in the infrared-light region to pass therethrough; and

an infrared-light transmissive long-pass filter for permitting light mainly in the infrared-light region to pass therethrough.

12. The image sensor according to claim 9 , wherein the color filter comprises:

an all-transmissive filter for permitting light in a visible-light region and an infrared-light region to pass therethrough;

a long-pass filter for permitting light in the visible-light region equal to or longer than a yellow light wavelength and the infrared-light region to pass therethrough;

a long-pass filter for permitting light in the visible-light region equal to or longer than a red light wavelength and the infrared-light region to pass therethrough; and

an infrared-light transmissive long-pass filter for permitting light mainly in the infrared-light region to pass therethrough.

13. A video signal processing method of a video signal processing apparatus, comprising steps of:

receiving, on an image sensor, light through a color filter, the color filter including long-pass filters only or a combination of a long-pass filter and an all-transmissive filter, the long-pass filters in the color filter including a visible-light transmissive long-pass filter for permitting a visible-light component and an infrared-light component to pass therethrough and an infrared-light transmissive long-pass filter for permitting an infrared-light component to pass selectively therethrough; and

removing an infrared-light component contained in a signal having passed through the visible-light transmissive long-pass filter, with transmittance data of an infrared-light region of the visible-light transmissive long-pass filter and the infrared-light transmissive long-pass filter applied.

14. The video signal processing method according to claim 13 , wherein the step of removing the infrared-light component comprises:

calculating a parameter that reduces to approximately zero the infrared-light component contained in the signal having passed through the visible-light transmissive long-pass filter, with the transmittance data of the infrared-light region of the visible-light transmissive long-pass filter and the infrared-light transmissive long-pass filter applied, and

generating, with the calculated parameter applied, a color signal being a visible-light component that is obtained by removing the infrared-light component from the signal having passed through the visible-light transmissive long-pass filter.

15. A non-transitory computer-readable storage medium storing a computer program which, when executed by a video signal processing apparatus, causes the video signal processing apparatus to perform a video signal processing method, the method including:

receiving, on an image sensor, light through a color filter, the color filter including long-pass filters only or a combination of a long-pass filter and an all-transmissive filter, the long-pass filters in the color filter including a visible-light transmissive long-pass filter for permitting a visible-light component and an infrared-light component to pass therethrough and an infrared-light transmissive long-pass filter for permitting an infrared-light component to pass selectively therethrough; and

removing an infrared-light component contained in a signal having passed through the visible-light transmissive long-pass filter, with transmittance data of an infrared-light region of the visible-light transmissive long-pass filter and the infrared-light transmissive long-pass filter applied.