The Imagick::reduceNoiseImage() function is an inbuilt function in PHP which is used to smooth the contours of an image while preserving edge information. This function replace each pixel by its neighbor closest in value. A neighbor is defined by radius.
bool Imagick::reduceNoiseImage( $radius )
Parameters: This function accepts single parameter $radius which is used to store the value of the radius.
Return Value: This function returns True on success.
This article is attributed to GeeksforGeeks.org