160 likes | 312 Views
Kernel Similarity Modeling of Texture Pattern Flow for Motion Detection in Complex Background. Baochang Zhang, Yongsheng Gao , Sanqiang Zhao, Bineng Zhong. 2011 IEEE transection on CSVT. Outline. TPF Operator Kernel Similarity Modeling Experiment Result Conclusion.
E N D
Kernel Similarity Modeling of Texture Pattern Flow for Motion Detection in Complex Background Baochang Zhang, YongshengGao, Sanqiang Zhao, BinengZhong 2011 IEEE transection on CSVT
Outline • TPF Operator • Kernel Similarity Modeling • Experiment Result • Conclusion
TPF Operator-Spatial • Given a gray-scale image sequence • To capture the spatial variations in x and y directions, two threshold functions, and , are employed to encode the gradient information into binary representations
TPF Operator-Temporal • The temporal derivative is defined as • A pixel value lying within 2.5 standard deviations of a distribution is defined as a match match
TPF Operator • By integrating both spatial and temporal information, the TPF is defined as • TPF reveals the relationship between derivative directions in both spatial and temporal domains
Integral Histogram of TPF • Using a neighborhood region provides certain robustness against noise • When the local region is too large, the more details will be lost
Building Background Model • Use GMM to model the background • If a match has been found for the pixel, update mean and variance of the matched Gaussian distribution • If none of the K Gaussian distributions match the current pixel value, the least probable distribution is replaced with a new distribution whose mean is the current pixel value
Kernel Similarity Measurement • We use k to represent the result of kernel similarity • With the information of kernel similarity, we can get an adaptive threshold to classify the input pixel : mean of the th Gaussian distribution at time t : variance of the th Gaussian distribution at time t : model integral histogram : learning rate
Update the Background Model • If the pixel is labeled as background, the background model histogram with the highest similarity value will be updated with the new data : input integral histogram : 1 for the best-matched distribution, 0 for the other distributions
Experiment Results • All the experiments in this paper are conducted on gray-level values • For simplicity, 3 Gaussian distributions and 3 model integral histograms are used to describe all the Gaussian mixture models • = 0.7, = 0.01
Experiment 2 Wallflower video GMM CMU LBP TPF KSM-TPF
Experiment 2 GMM CMU LBP TPF KSM-TPF
Conclusion • KSM-TPF is much more robust to significant background variations • However, it is less computationally efficient than the GMM method or LBP method