针对时空上下文跟踪算法对快速运动和遭受严重遮挡目标的跟踪精度下降问题,提出一种融合卡尔曼滤波的改进时空上下文跟踪算法。首先人工标记目标所在的矩形区域,然后利用改进的时空上下文算法对目标进行稳定跟踪,在跟踪过程中,基于连续两帧图像灰度的欧氏距离判定目标跟踪状态,当判定目标遭受严重遮挡时,利用卡尔曼滤波进行预测估计。算法对噪声有一定的容忍度,通过降低噪声对跟踪过程的影响,能够得到更优的目标区域。仿真实验结果表明:本文算法适用于不同光照强度下高速、高机动目标的稳定跟踪,并且对目标的尺度变化和短时严重遮挡具有鲁棒性。算法帧平均耗时为34.07ms;帧几何中心平均误差为5.43pixel,比时空上下文算法减少70.2%;目标轮廓面积平均误差为13.08%,比时空上下文算法减少52.7%。
For the rapid target suffering from severe occlusion,the tracking accuracy of spatio-temporal context algorithm decreases.A novel tracking algorithm of improved spatio-temporal context with Kalman filter is proposed in the paper.The rectangular region of the tracking object is manually marked at the first frame,and the improved spatio-temporal context algorithm is then applied to track the target.The Euclidean distance of the image intensity in two consecutive frames determines the state of the target in the tracking process.We apply Kalman filter to reduce the influence of noise and predict and estimate the possible position of the target under severe occlusion,and obtain better rectangular region of the tracking object.The experimental results show that the algorithm of improved spatio-temporal context with Kalman filter can be used for high speed and highly maneuvering tracking target with different light intensities,and is robust for the target with varied scale and severe occlusion.Time consumption per frame is 34.07 ms.Geometric center error per frame is 5.43 pixel,70.2%less than that via the spatio-temporal context algorithm.The contour area per frame is 13.08%,52.7%less than that via the spatio-temporal context algorithm.