An image taken through an optical lens is bright in the center and darker toward the edges. Such phenomenon results from decreases in the amount of light in the peripheral area of an image specifically, since light enters diagonally in the peripheral area. The shading correction core uses a 2-dimensional shading function F(x,y) to correct shading image. F(x,y) presents the brightness of image in x and y direction. F(x,y) is a quadratic polynomial with coefficients independently for each direction and color. We provide the program to calculates the coefficients of F(x,y) with the shading correction core. This program calculates the coefficients of F(x,y) using the shading image captured from the white color image in a proper lighting condition.
|2-dimensional shading function, F(x,y) = Ax^2 + Bx + C + Dy^2 + Ey + Gxy|
|Provide the program that calculates the shading function coefficients|