Granted Patent B2

US 9,530,056 · App. 13/524,557 · Granted Dec 27, 2016

Abstract

Claims (46)

1. A method for classifying an image as being one of a daytime image or a nighttime image, said method comprising:

obtaining an image captured by a camera;

analyzing said obtained image with an image processor, said analyzing including:

determining a first parameter representative of a combination of a first amount of pixels in substantially the entire image that are sufficiently red and a second amount of pixels in substantially the entire image that are sufficiently yellow; and

determining a second parameter representative of a third amount of pixels in substantially the entire image that are sufficiently light; and

classifying the image as one of a daytime image or a nighttime image based upon the first and second parameters.

2. The method of claim 1 , said analyzing further comprising:

converting the obtained image from a first color space to a Hue-Saturation-Value (HSV) color space, wherein individual pixels of the image are defined by an H-component, an S-component, and a V-component.

3. The method of claim 2 , wherein determining the first parameter comprises:

counting a first number of pixels having an H-component that is equal to or less than a lower H-component threshold or equal to or more than an upper H-component threshold.

4. The method of claim 3 , wherein determining the first parameter further comprises:

computing a first histogram of the pixels' H-components, said first number being counted based on said first histogram.

5. The method of claim 3 , wherein determining the second parameter comprises:

counting a second number of pixels having a V-component that is equal to or more than a V-component threshold.

6. The method of claim 5 , wherein determining the second parameter further comprises:

computing a second histogram of the pixels' V-component, said second number being counted based on said second histogram.

7. The method of claim 1 , wherein if the first parameter is equal to or less than a first threshold or the second parameter is equal to or greater than a second threshold, then the image is classified as a daytime image.

8. The method of claim 1 , wherein if the first parameter is equal to or greater than a first threshold and the second parameter is equal to or less than a second threshold, then the image is classified as a nighttime image.

9. The method of claim 2 , wherein the obtained image is defined in the first color space, said first color space being a Red-Green-Blue (RGB) color space.

10. An apparatus that executes the method of claim 1 .

11. A non-transitory machine-readable medium including a computer program which when executed performs the method of claim 1 .

12. A camera system comprising:

a camera that obtains an image defined in a first color space; and

an image processor that:

determines a first parameter representative of a combination of a first amount of pixels in substantially the entire image that are sufficiently red and a second amount of pixels in substantially the entire image that are sufficiently yellow;

determines a second parameter representative of a third amount of pixels in substantially the entire image that are sufficiently light; and

classifies the image as one of a daytime image or a nighttime image based upon the first and second parameters.

13. The camera system of claim 12 , wherein said image processor is further operative to:

convert the obtained image from the first color space to a Hue-Saturation-Value (HSV) color space, wherein individual pixels of the image are defined by an H-component, an S-component, and a V-component.

14. The camera system of claim 13 , wherein determining the first parameter comprises:

counting a first number of pixels having an H-component that is equal to or less than a lower H-component threshold or equal to or more than an upper H-component threshold.

15. The camera system of claim 14 , wherein determining the first parameter further comprises:

computing a first histogram of the pixels' H-components, said first number being counted based on said first histogram.

16. The camera system of claim 14 , wherein determining the second parameter comprises:

counting a second number of pixels having a V-component that is equal to or more than a V-component threshold.

17. The camera system of claim 16 , wherein determining the second parameter further comprises:

computing a second histogram of the pixels' V-component, said second number being counted based on said second histogram.

18. The camera system of claim 12 , wherein if the first parameter is equal to or less than a first threshold or the second parameter is equal to or greater than a second threshold, then the image is classified as a daytime image.

19. The camera system of claim 12 , wherein if the first parameter is equal to or greater than a first threshold and the second parameter is equal to or less than a second threshold, then the image is classified as a nighttime image.

20. The camera system of claim 13 , wherein the first color space is a Red-Green-Blue (RGB) color space.

21. A method for classifying an image as being one of a daytime image or a nighttime image, said method comprising:

obtaining an image captured by a camera;

analyzing said obtained image with an image processor, said analyzing including:

determining a first parameter representative of at least one of: (i) a combination of an amount of pixels in substantially the entire image that are sufficiently red and an amount of pixels in substantially the entire image that are sufficiently yellow; or (ii) a combination of an amount of pixels in substantially the entire image that are sufficiently blue and an amount of pixels in substantially the entire image that are sufficiently green; and

determining a second parameter representative of at least one of: (i) an amount of pixels in substantially the entire image that are sufficiently light; or (ii) an amount of pixels in substantially the entire image that are sufficiently dark; and

classifying the image as one of a daytime image or a nighttime image based upon the first and second parameters.

Assignments (11)