In this work, we propose a system to estimate head poses only using depth information in real-time. An optimization method based on 3D model fitting is developed. We iteratively minimize the distance between source and target point clouds of a user’s head. The method give fully real-time responses (30fps) without the GPU speedup. We adopt a commodity depth sensor named Microsoft Kinect as well as Asus Xtion, and use the depth image as the only input so that our system will not be affected by illumination variations. However, the simplicity of this acquisition device comes at the cost of frequent noises in the acquired data. We demonstrate that 6 degrees of freedom real-time head motion tracking in 3D space can be achieved with such noisy depth data.
4. What’s Head Motion Tracking
4
Y-axis
Yaw
Pitch
Roll
Y translation
Real-time reconstruction of this 6-DoF motion vector
given a stream of video input.
5. 5
Why Head Motion Tracking
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6. Related Work
• Color Image Based Methods
“Head Pose Estimation in Computer Vision : A Survey”,
E. Murphy-Chutorian and M. M. Trivedi., PAMI 09
• Appearance Template Methods
• Feature Tracking Methods
• Detector Arrays
• Nonlinear Regression Methods
• Manifold Embedding Methods
• Flexible Models
• Geometric Methods
• Hybrid Methods
• Too sensitive to illumination variations! 6
8. • Kinect by Microsoft
– $149.99
• Xtion Pro by Asus
– $189 .
– $300 .
8
Depth Camera
9. 9
Related Work
“Real-time performance-based facial animation”
T. Weise et al., SIGGRAPH 2011
“Real Time Head Pose Estimation with Random Regression
Forests”,
G. Fanelli et al., CVPR 2011
13. Flow Chart
Least Square Error Method
Inverse Rotation
Nose Detection
Sampling
Iterative Optimization Method
User Acting Avatar Control
13
Depth Data
Acquisition Real-time Head Pose Estimation
25. 26
User Acting
Flow Chart
Least Square Error Method
Inverse Rotation
Nose Detection
Sampling
Depth Data
Iterative Optimization Method
Acquisition
Real-time Head Pose Estimation
Avatar Control