1. An apparatus for performing digital image processing, the processing including computing optima of a function of the digital image, the apparatus comprising: circuitry configured to initialize a plurality of candidate points that lie in a solution space of the function, each candidate point being represented by a vector having a length equal to the dimension of the function, compute, based on the candidate points, one or more stationary points of the function, deflate a gradient of the function at each of the one or more computed stationary points, repeat the computing and the deflating until a first criteria is satisfied, select, from the one or more computed stationary points, a predetermined number of fit points, recombine the selected fit points to generate a set of new candidate points, repeat, for the set of new candidate points, the computing, the deflating, the first repeating, the selecting, and the recombining, until a second criteria is satisfied, obtain, the optima of the function upon the second criteria being satisfied, and process the digital image based on the obtained optima.