map

framing

Function map 

Source 
pub fn map<T, F, U>(map: F, frame: T) -> Map<T, F, U>
where
    T: Image,
    F: Fn(T::Pixel) -> U,
Expand description

Constructs a pointwise mapping over a frame.

You can use this to, for example, convert between pixel formats, or invert all the colors.