controlling a computer by hand gestures · introduction •overview 3 pic from multi-touch -...
TRANSCRIPT
Controlling a Computer by hand
gestures
Supervisor: Yuchao Dai, Laurent Kneip, Hongdong Li
Student: Bohuai Jiang u4652552
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Content
• Introduction
• Technique review
• Design and Implementation
• Experiment and Evaluation
• Conclusion and Future works
Introduction
• Overview
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Pic from Multi-touch - Wikipedia, the free encyclopedia. 2014. Multi-
touch - Wikipedia, the free encyclopedia. [ONLINE] Available
at:http://en.wikipedia.org/wiki/Multi-
touch#mediaviewer/File:Multitouch_screen.svg. [Accessed 02
November 2014].
Introduction
• Overview
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Pic from Multi-touch - Wikipedia, the free encyclopedia.
2014. Multi-touch - Wikipedia, the free encyclopedia. [ONLINE]
Available at:http://en.wikipedia.org/wiki/Multi-
touch#mediaviewer/File:Multitouch_screen.svg. [Accessed 02
November 2014].
Introduction
• Overview
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Pics form Geekerific home, controlled by voice and hand
gestures - AGBeat. 2014.Geekerific home, controlled by
voice and hand gestures - AGBeat. [ONLINE] Available
at: http://agbeat.com/tech-news/geekerific-home-controlled-
voice-hand-gestures/. [Accessed 02 November 2014].
Introduction
• Objective– Build a robust and real time human hand pose estimation and
tracking system.
– Data collected form RGB-Depth Camera
– Mainly focused on :
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hand Model construction Cost function computation optimization
3.How to use the RGB-D camera "Asus xtion pro" with ROS. - DASL MediaWiki.
2014. 3.How to use the RGB-D camera "Asus xtion pro" with ROS. - DASL
MediaWiki. [ONLINE] Available
at:http://dasl.mem.drexel.edu/wiki/index.php/3.How_to_use_the_RGB-
D_camera_%22Asus_xtion_pro%22_with_ROS.. [Accessed 02 November 2014].
Technique review
• Iteration Closet Point (ICP)
• Gradient descent
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Technique review
• Iteration closest point (ICP)– Algorithm employed to minimize the difference
between two point clouds by iterations
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Pic from Documentation - Point Cloud Library (PCL). 2014. Documentation - Point Cloud Library (PCL). [ONLINE] Available at:http://pointclouds.org/documentation/tutorials/interactive_icp.php. [Accessed 03 November 2014].
Technique review
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Technique review
• Basic Iteration Closet Point
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Technique review
• Iteration Closet Point in hand tracking and
optimization
– Point-model alignment task
– Require more complex ICP
– Gradient descent base ICP
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Technique review
• Gradient descent
– Widely using for multivariable function
optimization.[1][2][3]
– Easy and simple to be understood
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Gradient descent - Wikipedia, the free encyclopedia. 2014. Gradient descent - Wikipedia, the free encyclopedia. [ONLINE] Available at:http://en.wikipedia.org/wiki/Gradient_descent. [Accessed 03 November 2014].
Technique review
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Image form Tuning the learning rate in Gradient Descent | Datumbox. 2014. Tuning the learning rate in Gradient Descent | Datumbox. [ONLINE] Available at:http://blog.datumbox.com/tuning-the-learning-rate-in-gradient-descent/. [Accessed 03 November 2014].
Technique review
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Design and Implementation
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Design and Implementation
• Model construction
• Cost function
• Gradient-base ICP
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Design and Implementation
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Design and Implementation
• Model – Adopt commonly used 26 degree of freedom model.
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Image form Qian, C., Sun, X., Wei, Y., Tang, X., & Sun, J. Realtime and
Robust Hand Tracking from Depth.2014
Design and Implementation
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Design and Implementation
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Design and Implementation
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Design and Implementation
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Design and implementation
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Design and implementation
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Design and implementation
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Design and implementation
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Design and implementation
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Design and implementation
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Design and implementation
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Design and implementation
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Design and implementation
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Design and implementation
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Design and implementation
• Gradient descent implementation
- Created self-adjust lambda
Time complexity:
O(10*|M|*|sub(P)|)
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Design and implementation• Gradient descent base ICP
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Experiment and Evaluation
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Experiment and Evaluation
• ExperimentGround truth:
• Used from CVPR14 at
http://research.microsoft.com/en-/um/people/yichenw/handtracking/index.html
Goal:
1.Test gradient-descent base ICP performance for last frame
initialization.
2.Test gradient-descent base ICP performance for random
initialization.
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Experiment and Evaluation
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Experiment and Evaluation
• Random initialization.
– Steps:1. Add random noise between −1° 𝑡𝑜 1° to all rotation
variable from DOF26, and Add random value between -1 to
1 to all translation variable from DOF26
2. Run ICP and compute error
3. Increasing random value range. And Repeat step 1 and
step 2.
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Experiment and Evaluation• Result for last frame initialization
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Experiment and Evaluation
• Result for Random initialization
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Conclusion and Future Work
• Conclusion– Gradient descent base ICP is not feasible for hand tracking and
pose estimation.
• It is acceptable to optimize last frame initialization hand model
• Performed poorly on random initialization
– Its performance should be improve using stochastic optimization
such as PSO.
– Gradient descent base ICP has a great potential of
improvements
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Future work
• Replace random selection by other sample techniques,
such as systematic sampling.
• More scalable hand model need to be implemented so
that it can used for general data
• Set constraints to DOF26 to avoid counter-intuitive hand
pose generated by hand model
• implement stochastic optimization to out ICP
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Thanks for listening
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Reference
[1]Li, Z., Chen, J., Chong, A., Yu, Z., & Schraudolph, N. N.. Using stochastic gradient-descent scheme
in appearance model based face tracking. In Multimedia Signal Processing, 2008 IEEE 28 10th
Workshop on (pp. 640-645).in IEEE.2008
[2] Bray, M., Koller-Meier, E., Müller, P., Van Gool, L., & Schraudolph, N. N.. 3D hand tracking by rapid
stochastic gradient descent using a skinning model. In In 1st European Conference on Visual Media
Production in CVMP. 2004
[3] Hou, S., Galata, A., Caillette, F., Thacker, N., & Bromiley, P.. Real-time body tracking using a
gaussian process latent variable model. InComputer Vision, 2007. ICCV 2007. IEEE 11th International
Conference on (pp. 1-8). IEEE. In 2007
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