1. A method comprising: receiving a plurality of image datasets, each image dataset acquired at one of a plurality of time points, from an image acquisition device; storing the plurality of image datasets in a data storage device; selecting a first dataset corresponding to a first time point; selecting a first group of datasets corresponding to a range of time points that includes the first time point; and generating, using a data processor, an output image corresponding to the first time point according to a non-convex prior image constrained compressed sensing algorithm performed on the first data using information from the first group of datasets; where the algorithm minimizes a non-convex objective function using non-convex priors l p -functional in which 0<p<1.