1. A computer-implemented method of reconstructing a time series of target images acquired by an imaging system, comprising the steps of: obtaining a set of Fourier transform measurements of a full-sampled reference image of a region of interest; extracting edge information from the set of Fourier transform measurements of the full-sampled reference image; obtaining a reduced set of Fourier transform measurements of a time series of target images of the region of interest; constructing sparse representations of the time series of target images from the reduced set of Fourier transform measurements; obtaining approximate edge information for the sparse representations of the time series of target images using the edge information extracted from the set of Fourier transform measurements of the full-sampled reference image; and reconstructing the time series of target images based on the reduced set of Fourier transform measurements of the time series of target images, and the approximate edge information for the sparse representations of the time series of target images.