Image processing device and method

1. An image processing device comprising:

an image obtaining unit configured to obtain a first image under a condition where an illuminance is substantially equal to or greater than a critical value, and to obtain a second image under a condition where the illuminance is less than the critical value;

a mode converter configured to convert an image processing mode into a first mode, in which color signal processing is performed on the first image, and a second mode, in which black-and-white signal processing is performed on the second image;

a color converter configured to convert a color of the first image by applying first color conversion data, including first conversion data and second conversion data, to the first image, and to convert a color of the second image by applying second color conversion data, including first conversion data and second conversion data, that is different from the first color conversion data to the second image; and

an image converter configured to convert the color converted second image into a third image, in which color information of the second image is converted into brightness information,

wherein the first conversion data is gain and the second conversion data is a color conversion matrix, and the gain of the second color conversion data is substantially equal to the gain of the first color conversion data.

2. The image processing device of claim 1 , wherein at least one of the first conversion data and the second conversion data of the second color conversion data is different from the other of the first conversion data and the second conversion data of the first color conversion data.

3. The image processing device of claim 1 , wherein the color conversion matrix of the second color conversion data is an identity matrix.

4. The image processing device of claim 1 , wherein the color conversion matrix of the second color conversion data is a combination of a color conversion matrix of the first color conversion data and an identity matrix.

5. The image processing device of claim 4 , wherein, in the color conversion matrix of the second color conversion data, a ratio of the identity matrix increases as the illuminance becomes lower than a critical value.

6. The image processing device of claim 1 , wherein the first image comprises visible ray band information, and the second image comprises the visible ray band and infrared ray (IR) band information.

7. A method of processing images comprising the steps of:

selecting an image processing mode from a first mode, in which color signal processing is performed on a first image obtained under a condition where illuminance is substantially equal to or greater than a critical value, and a second mode, in which black-and-white signal processing is performed on a second image obtained under a condition where the illuminance is less than the critical value;

if the first mode is selected, converting a color of the first image by applying first color conversion data including first conversion data and second conversion data to the first image;

if the second mode is selected, converting a color of the second image by applying second color conversion data, including first conversion data and second conversion data, that is different from the first color conversion data to the second image, the first conversion data comprising a gain and the second conversion data comprising a color conversion matrix, and the gain of the second color conversion data being substantially equal to the gain of the first color conversion data; and

converting the color converted second image into a third image, including converting the color information of the second image into brightness information.

8. The method of claim 7 , wherein at least one of the first conversion data and the second conversion data of the second color conversion data is different from the other of the first conversion data and the second conversion data of the first color conversion data.

9. The method of claim 7 , wherein the color conversion matrix of the second color conversion data is an identity matrix.

10. The method of claim 7 , wherein the color conversion matrix of the second color conversion data is a combination of a color conversion matrix of the first color conversion data and an identity matrix.

11. The method of claim 10 , wherein in the color conversion matrix of the second color conversion data, a ratio of the identity matrix increases as the illuminance becomes lower than the critical value.

12. The method of claim 7 , wherein the first image comprises visible ray band information, and the second image comprises the visible ray band information and infrared ray (IR) band information.

13. An image processing device comprising:

an image obtaining unit configured to obtain a first image under a condition where an illuminance is substantially equal to or greater than a critical value, and to obtain a second image under a condition where the illuminance is less than the critical value;

a mode converter configured to convert an image processing mode into a first mode, in which color signal processing is performed on the first image, and a second mode, in which black-and-white signal processing is performed on the second image;

a color converter configured to convert a color of the first image by applying first color conversion data including first conversion data and second conversion data to the first image, and to convert a color of the second image by applying second color conversion data, including first conversion data and second conversion data, that is different from the first color conversion data to the second image; and

an image converter configured to convert the color converted second image into a third image, in which color information of the second image is converted into brightness information,

wherein the first conversion data is a gain and the second conversion data is a color conversion matrix, and

wherein the gain of the second color conversion data is adjusted based on a light source information and the adjusted gain is a combination of the gain of the first color conversion data and the gain of the second color conversion data, and the color conversion matrix of the second color conversion data is an identity matrix or a combination of the color conversion matrix of the first color conversion data and an identity matrix.

14. A method of processing images comprising the steps of:

selecting an image processing mode from a first mode, in which color signal processing is performed on a first image obtained under a condition where illuminance is substantially equal to or greater than a critical value, and a second mode, in which black-and-white signal processing is performed on a second image obtained under a condition where the illuminance is less than the critical value;

if the first mode is selected, converting a color of the first image by applying first color conversion data including first conversion data and second conversion data to the first image;

if the second mode is selected, converting a color of the second image by applying second color conversion data, including first conversion data and second conversion data, that is different from the first color conversion data to the second image, the first conversion data comprising a gain and the second conversion data comprising a color conversion matrix, the gain of the second color conversion data being adjusted based on a light source information and the adjusted gain being a combination of the gain of the first color conversion data and the gain of the second color conversion data, and the color conversion matrix of the second color conversion data being an identity matrix or a combination of the color conversion matrix of the first color conversion data and an identity matrix; and

converting the color converted second image into a third image, including converting the color information of the second image into brightness information.