1. An imaging system comprising: an edge-detecting module configured to detect one or more edge coordinates of at least a reference line in a first image; first and second disparity-estimating modules respectively configured to obtain a current line of a first estimated disparity map of the first image with respect to a second image and a second estimated disparity map of the second image with respect to the first image; a cross-checking module configured to cross check the current line of the first estimated disparity map using the current line of the second estimated disparity map to identify a set of occlusion pixels in the current line of the first estimated disparity map; an occlusion-refining module configured to refine the set. of occlusion pixels to create a refined set of occlusion pixels; and a hole-filling module configured to fill the refined set of occlusion pixels in the current line of the first estimated disparity map to obtain a current line of a first refined disparity map, wherein the first disparity-estimating module comprises a first cost-aggregating module comprising a first aggregation window buffer and being configured to obtain correlation lines of the first image and the second image, calculate current matching costs of the correlation line of the first image with respect to the correlation line of the second image for a plurality of disparity distances, aggregate matching costs using the first aggregation window buffer and the current matching costs for the plurality of disparity distances, and update the first aggregation window buffer with the current matching costs; and a first disparity-selecting module configured to select, respectively for each pixel on a current line of a first estimated disparity map, one of the disparity distances as a disparity level at the pixel of the first estimated disparity map.