Question

What is the general form of representation of power transformation?

(a) s=cr^γ

(b) c=sr^γ

(c) s=rc

(d) s=rc^γ

The question was asked during a job interview.

This interesting question is from Basic Intensity Transformation Functions topic in division Intensity Transformations and Spatial Filtering of Digital Image Processing

Answer 1

The correct option is (a) s=cr^γ

The best I can explain: Power-law transformations have the basic form: s=cr^γ where c and g are positive constants. Sometimes s=cr^γ is written as s=c.(r+ε)^γ to account for an offset (that is, a measurable output when the input is zero).