Week 9 Presented by Christina Peterson
Recognition Accuracies on UCF Sports data set Method Accuracy (%)DivingGolfingKickingLiftingRidingRunningSkating Swing- bench High- swingWalking Rodriguez et al. [1] Yeffet and Wolf [2] Le et al. [4] Wu et al. [6] Action Bank [7] Standard Multiclass-SVMs Combined Exemplar-SVMs
Confusion Matrix: Standard Multi-Class SVM DiGoSsSbSkRuHoLiKiWa Diving Golf Kick Lift Horse-Ride Run Skateboard Swing-bench Swing-side Walk
Confusion Matrix: Combined Exemplar-SVM DiGoSsSbSkRuHoLiKiWa Diving Golf Kick Lift Horse-Ride Run Skateboard Swing-bench Swing-side Walk
Standard Linear vs. Exemplar
Conclusions Need to improve the method used to combine the exemplar scores Currently, a multiclass-svm is trained on the decision values of the exemplars on the validation set Possible Solution: Create a strong action classifier using the boosting algorithm of Viola and Jones[8] Treat the exemplar-svms as weak classifiers
References [1] M. D. Rodriguez, J. Ahmed, and M. Shah. Action mach: A spatio-temporal maximum average correlation height filter for action recognition. In CVPR, [2] Yeffet and L. Wolf. Local trinary patterns for human action recognition. In ICCV, [3] H. Wang, M. Ullah, A. Klaser, I. Laptev, and C. Schmid. Evaluation of local spatio- temporal features for action recognition. In BMVC, [4] Q. Le, W. Zou, S. Yeung, and A. Ng. Learning hierarchical invariant spatiotemporal features for action recognition with independent subspace analysis. In CVPR, [5] A. Kovashka and K. Grauman. Learning a hierarchy of discriminative spacetime neighborhood features for human action recognition. InCVPR, [6] X. Wu, D. Xu, L. Duan, and J. Luo. Action recognition using context and appearance distribution features. InCVPR, [7] S. Sadanand and J. J. Corso. Action bank: A high-level representation of activity in video. CVPR, [8] P. Viola and M. Jones. Robust real-time face detection. International Journal of Computer Vision, 57(2):137–154, May 2004.