Histogram of Oriented Principal Components for Cross-View Action Recognition

By Hossein Rahmani, Arif Mahmood, Du Q. Huynh, Ajmal Saeed Mian. 2014

194 citations recorded by the source corpus.

Existing techniques for 3D action recognition are sensitive to viewpoint variations because they extract features from depth images which are viewpoint dependent. In contrast, we directly process point clouds for cross-view action recognition from unknown and unseen views. We propose the histogram of oriented principal components (HOPC) descriptor that is robust to noise, viewpoint, scale and action speed variations. At a 3D point, HOPC is computed by projecting the three scaled eigenvectors of the pointcloud within its local spatio-temporal support volume onto the vertices of a regular dodecahedron. HOPC is also used for the detection of spatiotemporal keypoints (STK) in 3D pointcloud sequences so that view-invariant STK descriptors (or Local HOPC descriptors) at these key locations only are used for action recognition. We also propose a global descriptor computed from the normalized spatio-temporal distribution of STKs in 4-D, which we refer to as STK-D. We have evaluated the performance of our proposed descriptors against nine existing techniques on two cross-view and three single-view human action recognition datasets. The experimental results show that our techniques provide significant improvement over state-of-the-art methods.

Subfields: Biomedical Engineering, Computer Vision and Pattern Recognition, Human-Computer Interaction

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Biomedical Engineering

  1. Jun Liu
  2. G. Wang
  3. Hossein Rahmani
  4. Alex ChiChung Kot
  5. Amir Shahroudy
  6. Ling-yu Duan
  7. Qiuhong Ke
  8. Ajmal Saeed Mian

In Computer Vision and Pattern Recognition

  1. Jun Liu
  2. G. Wang
  3. Hossein Rahmani
  4. Amir Shahroudy
  5. Alex ChiChung Kot
  6. Ling-yu Duan
  7. Qiuhong Ke
  8. Luc Van Gool

In Human-Computer Interaction

  1. Hossein Rahmani
  2. Jun Liu
  3. Ajmal Saeed Mian
  4. G. Wang
  5. Mubarak Shah
  6. Amir Shahroudy
  7. Seungryul Baek
  8. Alex ChiChung Kot

Citations in the corpus