Anisotropic Diffusion for Details Enhancement in Multiexposure Image Fusion

Figure 11

The effect of weight (i.e., 𝑎) on sigmoid function and derivative of sigmoid function. (a) The sharpness of the sigmoid in (28) varies according to the value of weight. With larger value of 𝑎, the sigmoid becomes a threshold function. (b) The first derivative of sigmoid function in (29) for 𝑎=2 and 𝑎=3.

(a)

(b)