An electronic device [100] estimates a depth map of an environment based on stereo depth images [410, 415] captured by depth cameras [114, 115] having exposure times that are offset from each other in conjunction with illuminators [118, 1119] pulsing illumination patterns [305, 310] into the environment. A processor [220] of the electronic device matches small sections [430, 432] of the depth images from the cameras to each other and to corresponding patches of immediately preceding depth images (e.g., a spatio-temporal image patch 'cube'). The processor computes a matching cost for each spatio-temporal image patch cube by converting each spatio-temporal image patch into binary codes and defining a cost function between two stereo image patches as the difference between the binary codes. The processor minimizes the matching cost to generate a disparity map, and optimizes the disparity map by rejecting outliers using a decision tree with learned pixel offsets and refining subpixels to generate a depth map of the environment.
SYSTEM AND METHOD FOR ACTIVE STEREO DEPTH SENSING