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Developing a 2.5-D video avatar

Tamagawa, K.; Yamada, T.; Ogi, T.; Hirose, M.;Signal Processing Magazine, IEEE

Volume 18, Issue 3, May 2001 Page(s):35 - 42

Speaker:許欽和

DATE:2001/03/30

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Outline

• Introduction

• The proposed scheme

• Experiment and experimental result

• Conclusion

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Introduction

• Immersive projection technology– computer augmented booth for image navigation

(CABIN)– CAVE– COSMOS

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CABIN

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CAVE

Graphics by Milana Huang, University of Illinois at Chicago

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• The user’s positional relationship can be shared in virtual space.

• The user’s facial expression cannot be transmitted.

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• Communications in the field of computer supported cooperative work– For example :webcam

• the communication space are 2-D,and the positional relationship between the users cannot be changed

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3-D information

• transmit 3-D information– user’s spatial position– gestures

• 3-D collaborative workspace– high quality of presence

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2.5-D video avatar

• developed a 2.5-D video avatar method– depth information from stereo cameras

• linked between CABIN and COSMOS

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2-D Video Avatar(1/2)

• 2-D Video Avatar– It is a requirement of networked immersive

projection environments

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2-D Video Avatar(2/2)

• IN CABIN

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The proposed scheme

• 2.5-D Video Avatar– Real-time modeling– Using stereo cameras

• A surface model of the user is formed using the depth information obtained in all directions

– The distortion of the image appears to be small

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Switching the surface model

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Depth Map by Stereo Camera

• Triclops stereo camera system– Has three lenses using two baselines horizontally a

nd vertically– Rectified image – Depth map

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Images generated by stereo camera

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Generation of 2.5-D Video Avatar

• 2.5-D video avatar is generated by texture-mapping the color image onto the triangular mesh.

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The process of making a 2.5-D video avatar

(1) determined in the camera’s coordinate system for each pixel in the depth map

(2) triangular mesh is created from the coordinates

(3) just the user’s image is segmented from the background

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Switching Multiple Cameras

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Switching Camera

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Implementation of 2.5-D Video Avatar

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Application of 2.5-D Video Avatar

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Experiment

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Experimental result

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Conclusion

• we experimentally evaluated the accuracy of pointing when using the 2.5-D video avatar

• Improving– reality of the image– time lag– refresh rate of the video avatar

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