1. A method of merging a plurality of disparity maps, comprising: calculating a plurality of disparity maps each from images captured by another of a plurality of pairs of image sensors having stereoscopic fields of view (SFOVs) with at least one overlapping portion, said SFOVs covering a scene with a plurality of objects, wherein a first pair of said image sensors is arranged to cover a first of said SFOVs far from said image sensors and a second pair of said image sensors is arranged to cover a second of said SFOVs near said image sensors between said first SFOVs and said image sensors, said at least one overlapping portion of said first SFOVs and said second SFOVs is located between said image sensors and said first SFOVs; identifying at least one of said plurality of objects in said at least one overlapping portion, said at least one object being mapped in each said disparity map; calculating accuracy of disparity values depicting said object in each said disparity map; merging depth data from said plurality of disparity maps according to said accuracy so as to provide a combined depth map wherein disparity values of said object are calculated according to one of said plurality of disparity maps; and outputting said depth data.