Functions > Image Processing > Image Manipulation > Function and Level Mapping
  
Function and Level Mapping
funmap(M, f)—Returns matrix M with function f applied to each element.
levelmap(M, vec)—Returns a matrix with intensity values specified by the vector vec by mapping pixel intensities in matrix M to vec's indices.
The levelmap function does not use the built-in variable ORIGIN that specifies the starting index of an array for other functions.
Arguments
M is an image matrix.
f is a function in one variable.
vec is a vector of real numbers between 0 and 255, inclusive. The last index of vec must equal the highest intensity in M.