1. A method for crystal identification in nuclear imaging systems, comprising: generating a flood image which includes a plurality of peaks, each peak responsive to received radiation, each peak corresponding to a corresponding scintillator crystal; partitioning the flood image into a plurality of regions, each region being masked to correspond to one of an array of nuclear detectors; fitting at least one Gaussian model to each peak; generating a model image in which the fitted Gaussian models represent the identified peaks; determining misidentified peaks in the model image in which locations of the peaks in the flood image differ from the corresponding scintillator crystal; and correcting the location of the misidentified peaks in the flood image based on at least one of (i) global knowledge of all peaks and (ii) local knowledge of neighboring peaks in the model image.