Detection Human Motion with Heel Strikes for Surveillance Analysis

Heel strike detection is an important cue for human gait recognition and detection in visual surveillance since the heel strike position can be used to derive the gait periodicity, stride and step length. We propose a novel method for heel strike detection using a gait trajectory model, which is robust to occlusion, camera view and to low resolution which can generalize to a variety of surveillance imagery. When a person walks, the movement of the head is conspicuous and sinusoidal. The highest point of the trajectory of the head occurs when the feet cross. Our gait trajectory model is constructed from trajectory data using non-linear optimization. Then, the key frames in which the heel strike takes place are extracted. A Region Of Interest (ROI) is extracted using the silhouette image of the key frame as a filter. Finally, gradient descent is applied to detect maxima which are considered to be the time of the heel strikes. The experimental results show a detection rate of 95% on two databases. The contribution of this research is the first use of the gait trajectory in the heel strike position estimation process and we contend that the approach is a new approach for basic analysis in surveillance imagery.