Perceptually Guided Synthesis and Compression of Motion Capture Data

  • Author / Creator
    Firouzmanesh, Amirhossein
  • Using motion capture data is an efficient way to generate and transmit 3D character animation. We explore the possibility of incorporating human perceptual factors in compression and synthesis of motion capture data in order to achieve a higher performance in different aspects including reducing the bandwidth requirement, decreasing processing time and transmission delay in different scenarios. First we show that by incorporating perceptual factors in wavelet-based compression, the processing time could be significantly reduced without noticeable degradation in the reconstruction quality. Experimental analysis shows that the proposed algorithm is much faster than comparable approaches using wavelets, thereby making our approach feasible for motion capture transmission, and real-time synthesis on mobile devices, where processing power and memory capacity are limited. We also propose a compression method based on using motion primitives. Using incremental encoding plus a database of motion primitives for each key point, our method achieves a higher or competitive compression rate with less online overhead. Trade-off between visual quality and bandwidth usage can be tuned by varying a single threshold value. A user study was performed to measure the sensitivity of human subjects to reconstruction errors in key rotation angles. While achieving real-time performance, our technique outperforms other methods in our experiments by achieving a compression ratio exceeding 50:1 on regular sequences without noticeable degradation in rendered qualities. Finally we propose a high efficiency, fast, scalable method for compressing motion capture clips taking advantage of a 1-D variation of the SPIHT algorithm. SPIHT provides near-optimal reconstruction error using the allocated bits. A 1-D variation of the original SPIHT is proposed that works with individual channels of motion capture data. Instead of time-consuming optimization process we combine 1-D SPIHT with a bit rate allocation mechanism based on perceptual factors to distribute the available bandwidth between the channels of data based on their importance in perceptual reconstruction quality of the motion. Our studies show that the proposed method is capable of compressing data at a rate of 40:1 to 60:1 with close to perfect reconstruction quality, which is generally better than the current methods in the literature.

  • Subjects / Keywords
  • Graduation date
    Fall 2014
  • Type of Item
  • Degree
    Doctor of Philosophy
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.