Patent ID: 9147114
Filing Date: 2015-09-29
Classification: G06K,G06T,H04N

Abstract:
1. A computer implemented method for tracking a target in a constrained environment in which motion of the target is constrained, the method comprising: obtaining and storing video frames from a series of video frames on a computer readable storage device; calculating probability estimates for target locations in each frame for targets in the constrained environment; and determining candidate target locations in each frame, wherein the probability estimate for target locations in a video frame ‘t’ is calculated in accordance with: where o t is a vector of the targets' observations for the video frame ‘t’, x t is a vector of targets' locations in the video frame ‘t’, x t-1 is a vector of the targets' locations in the frame ‘t−1’, P(x t ) is a joint probability of targets' locations, p(x t |o t ) is a probability of the target's locations given known observations, p(x t |x t-1 , x t-2 , . . . x 0 ) is a probability of current targets' locations given known past target locations, p(o t |x t ) is a probability of observations o t given known target locations x t and, p(x t ) models a joint prior probability of the targets' locations, and at least one of: a) wherein the target's locations are determined as a vector of locations that maximizes the probability for each location tar et is calculated in accordance with: and wherein the target observation probability for each target is assumed independent thus yielding where superscript indices 1, 2, . . . K refer to tracked targets, and b) the method further comprises simplification of the target propagation model and omitting interdependencies of propagation models among targets so that where superscript indices 1, 2, . . . K refer to tracked targets.