A Video Tracking System for Limb Motion Measurement in Small Animals

Motion analysis can provide useful information for biomedical researches. In this paper, we have presented a video tracking system for limb motion measurement in small animals. A consumer-grade video camera is used to capture the image sequences on the rat motion in the low-cost planar motion capture system. The tracking software consists of matching, prediction and mismatch detection. The matching is used to find the correspondence between the reference template and the search area in the analyzed frame. The prediction is important to limit the region of processing, thus reducing the execution time. The mismatch detection is applied to enable a motion tracking with high accuracy and reliability. For different contrast levels between markers and background, two matching algorithms, i.e. intensity-based and color-based algorithms, are used to find the positions of tracked markers. Moreover, based on the polynomial fitting and improved Kalman filtering algorithms, a new algorithm is presented to predict the joint positions in order to limit the matching region. Finally, some results of the 2-D motion tracking in sagittal plane for rats are presented.