1. A magnetic resonance imaging system, comprising: at least one radio frequency coil with a plurality of coil elements; a smart select unit the smart select unit constructing a signal map and a plurality of noise maps from a prior scan of a subject, the prior scan using the at least one radio frequency oil, wherein the noise maps are based on different sets of reduction factors along one or more reduction directions; a parallel imaging parameter unit which selects a set of reduction factors corresponding to a noise map which optimizes a signal-to-noise ratio and a scanning speed; a sequence control which performs a magnetic resonance imaging scan of the subject based on the selected reduction factors; a user interface which receives one of a maximum imaging time, an overall reduction factor, or a minimum signal-to-noise ratio; and wherein the smart select unit generates a plurality of sets of reduction factors, wherein the reduction factors are based on the received maximum imaging time or the received overall reduction factor.