Method for adjusting saturation and contrast of an area of an image and apparatus thereof

1. A method for adjusting saturation of an area of an image for the image to be displayed in an electronic system, the electronic system comprising a storage unit for storing information of the image and a processor, the method comprising:

calculating a deviation level of a pixel in the area of the image by the processor, the deviation level indicating brightness differences of the brightness values among the pixel and a pixel set in a vicinity of the pixel in the area of the image, the pixel set comprising pixels in the vicinity of the pixel of the area of the image; and

calculating a modified saturation value of the pixel in the area of the image according to the deviation level of the pixel in the area of the image and an original saturation value of the pixel in the area of the image to achieve saturation adjustment of the pixel in the area of the image by the processor.

2. The method of claim 1 wherein calculating the deviation level of the pixel in the area of the image comprises:

weighted-averaging brightness values of the pixels in the pixel set for generating an average brightness value; and

comparing an original brightness value with the average brightness value for generating the deviation level.

3. The method of claim 2 wherein weighted-averaging the brightness values of the pixels in the pixel set for generating the average brightness value comprises:

multiplying a brightness value of each pixel in the pixel set respectively by a preset weighted factor;

summing up multiplied brightness values of all pixels in the pixel set for generating a sum result; and

dividing the sum result by a number of the pixels in the pixel set for generating the average brightness value.

4. The method of claim 2 wherein comparing the original brightness value with the average brightness value for generating the deviation level comprises:

dividing the original brightness value of the pixel by the average brightness value for generating a brightness variation;

adjusting the brightness variation to generate an adjusted brightness variation; and

generating the deviation level according to a following equation: D=1+C×F, wherein D represents the deviation level, C represents a local gain, and F represents the adjusted brightness variation.

5. The method of claim 2 wherein comparing the original brightness value with the average brightness value for generating the deviation level comprises:

dividing the original brightness value of the pixel by the average brightness value and an anti-noise factor for generating an brightness variation;

adjusting the brightness variation to generate an adjusted brightness variation; and

generating the deviation level according to a following equation: D=1+L×F, wherein D represents the deviation level, L represents a local gain, and F represents the adjusted brightness variation.

6. The method of claim 1 wherein calculating a modified saturation value of the pixel in the area of the image according to the deviation level and the original saturation value of the pixel comprises calculating a modified saturation value of the pixel of the area of the image according to a following equation: M=S×D, wherein M represents the modified saturation value of the pixel, S represents the original saturation value of the pixel, and D represent the deviation level.

7. The method of claim 1 further comprising calculating a global gain for the area of the image by the processor.

8. The method of claim 7 wherein calculating the modified saturation value of the pixel in the area of the image according to the deviation level of the pixel in the area of the image and the original saturation value of the pixel in the area of the image to achieve saturation adjustment of the pixel in the area of the image is calculating the modified saturation value of the pixel in the area of the image according to the deviation level of the pixel in the area of the image, the global gain, and the original saturation value of the pixel in the area of the image to achieve saturation adjustment of the pixel in the area of the image.

9. The method of claim 8 wherein calculating the modified saturation value of the pixel in the area of the image according to the deviation level of the pixel in the area of the image, the global gain, and the original saturation value of the pixel in the area of the image to achieve saturation adjustment of the pixel in the area of the image comprises calculating the modified saturation value of the pixel in the area of the image according to a following equation: M=S×G×D, wherein M represents the modified saturation value of the pixel, S represents the original saturation value of the pixel, G represents the global gain, and D represents the deviation level.

10. The method of claim 8 wherein calculating the modified saturation value of the pixel in the area of the image according to the deviation level of the pixel in the area of the image, the global gain, and the original saturation value of the pixel in the area of the image to achieve saturation adjustment of the pixel in the area of the image comprises calculating the modified saturation value of the pixel in the area of the image according to a following equation: M=S×[1+(G−1)×D], wherein M represents the modified saturation value of the pixel, I represents the original saturation value of the pixel, G represents the global gain, and D represents the deviation level.

11. A method for adjusting contrast of an area of an image, comprising:

calculating a local contrast of a pixel set in a vicinity of a pixel by a processor, wherein the pixel is selected from the area and the pixel set is distributed in a portion of the area;

calculating a global gain for the area according to brightness characteristic of the area by the processor; and

calculating a modified brightness value of the pixel according to the local contrast, the global gain and an original brightness value of the pixel by the processor, so that contrast of the pixel is adjusted with the modified brightness value of the pixel.

12. The method of claim 11 wherein the local contrast is defined by a deviation level of the pixel, and the deviation level indicates brightness differences among the pixel and the pixel set in the vicinity of the pixel.

13. The method of claim 12 wherein the deviation level is determined according to a local gain.

14. The method of claim 12 wherein calculating the deviation level of the pixel in the area comprises:

weighted-averaging brightness values of the pixels in the pixel set for generating an average brightness value; and

comparing the original brightness value with the average brightness value for generating the deviation level.

15. The method of claim 14 wherein weighted-averaging brightness values of the pixels in the pixel set for generating the average brightness value comprises:

multiplying a brightness value of each pixel in the pixel set respectively by a preset weighted factor;

summing up multiplied brightness values of all pixels in the pixel set for generating a sum result; and

dividing the sum result by a number of the pixels in the pixel set for generating the average brightness value.

16. The method of claim 14 wherein comparing the original brightness value with the average brightness value for generating the deviation level comprises:

dividing the original brightness value of the pixel by the average brightness value for generating an brightness variation;

adjusting the brightness variation to generate an adjusted brightness variation; and

generating the deviation level according to a following equation: D=1+C×F, wherein D represents the deviation level, C represents a local gain, and F represents the adjusted brightness variation.

17. The method of claim 14 wherein comparing the original brightness value with the average brightness value for generating the deviation level comprises:

dividing the original brightness value of the pixel by the average brightness value and an anti-noise factor for generating an brightness variation;

adjusting the brightness variation to generate an adjusted brightness variation; and

generating the deviation level according to a following equation: D=1+L×F, wherein D represents the deviation level, L represents a local gain, and F represents the adjusted brightness variation.

18. The method of claim 12 wherein calculating a modified brightness value of the pixel according to the deviation level, the global gain and the original brightness value of the pixel comprises calculating a modified brightness value of the pixel according to a following equation: M=I×G×D, wherein M represents the modified brightness value of the pixel, I represents the original brightness value of the pixel, G represents the global gain, and D represents the deviation level.

19. The method of claim 12 wherein calculating a modified brightness value of the pixel according to the deviation level, the global gain and the original brightness value of the pixel comprises calculating a modified brightness value of the pixel according to a following equation: M=I×[1+(G−1)×D], wherein M represents the modified brightness value of the pixel, I represents the original brightness value of the pixel, G represents the global gain, and D represents the deviation level.

20. The method of claim 11 wherein the pixel set is determined by a predetermined rule.