Patent ID: 8600190

Claim:
A look-up-table (LUT) for forming an output image from a combination of two input images, the LUT comprising: first and second sets of gray levels, respectively, formed from first and second input images, and a third set of gray levels, calculated by a processor, for forming an output image, wherein the third set of gray levels is formed from the first and second sets of gray levels, and a pixel of the output image includes a gray level value of z that is dependent on a probability distribution function of gray levels in the LUT, expressed as p(z), where z is a gray level; and the LUT includes: a virtual two dimensional table having horizontal and vertical axes, x and y, wherein n is a maximum gray level value of the first set of gray levels, virtually placed along the vertical axis, n is a maximum gray level value of the second set of gray levels, virtually placed along the horizontal axis, A is an area in the LUT included within the horizontal and vertical axes and a diagonal line extending between the horizontal and vertical axes, through a point (x, y), then the gray level value, z, of the pixel is located on the diagonal line and is P −1 (k=A/(n 2 )), where k varies between 0 and 1.