Patent ID: 8675963

Claim:
A method of automatically adjusting a brightness of an image, the method comprising: generating a histogram of brightness values of pixels of an input image; generating a conversion function based on a cumulative distribution function and an inverse cumulative distribution function of the histogram; and generating an output image by applying, based on the conversion function, histogram equalization (HE) to the input image; wherein the HE is based at least partly on the cumulative distribution function or the inverse cumulative distribution function, a total numbers of pixels used for generating the histogram, and a maximum brightness value of the brightness values of the pixels of the input image; and wherein the inverse cumulative distribution function is generated according to Equation 2: CDF inv ( n )=Pixel total −CDF( n )+Hist( n ), Equation 2 where CDF inv denotes the inverse cumulative distribution function, Pixel total denotes a number of pixels used for generating the histogram, CDF denotes the cumulative distribution function, Hist denotes the histogram, and n denotes an integer greater than or equal to 0 and less than or equal to a maximum value of the brightness values.