Post on 04-Jun-2015
description
Internet-Wide Multi-Party Tele-Immersion Framework
for
Remote 3D Collaboration
RINU MARKS.PREG NO.73023rinumarks@gmail.com
Tele-Immersion is a new technology that enables a user to share a virtual space with remote participants.
WHAT IS TELE-IMMERSION ???
Existing System
• Video conferencing.• Fails to keep eye to eye contact.• User interaction is limitted.• When no. of persons conferencing
increases it will be hard to concentrate on person who is actually talking.
site 3site 1
site 2
BASIC CONCEPT
• Not merely the 3D reproduction of the human body.
• It also allows us to interact with virtual objects in the shared virtual environment
Interaction with virtual objects
• Tele-immersion reconstructs the objects in the real world in real-time, and mixes the real objects with the virtual environment
Remote Controller Function(wii)
• Various operations on 3d virtual objects such as “move”, “rotate”, “select”, “change texture”, “expand”, “shrink”, “highlight”
• Helps in eye to eye communication in multi party enironment.
ARRANGEMENTS
ARRANGEMENTS
•B&W cameras are for stereo construction.•The color camera is for extracting the appearance
ARRANGEMENT
3D IMAGE CONSTRUCTION
3D image construction
Stages in 3D conversion
• Acquisition stage• Reconstruction stage
Acquisition stage
• capture a variable amount of camera feeds .
• image-based calculations and color silhouette extraction.
• Image compression.
Sterio based reconstruction stage
Sterio based reconstruction1. Calculate initial matching cost
• and are the color intensities in the left and right images
• d is the disparity hypothesis.• denotes pixel in the left image
and denotes pixel in the right image
2. Construct a square window of predefined size with p as centre.
3. For each pixel q in window calculate adaptive support weight.
• and denotes the color and euclidean distance between p and q.
• are constants.
4. Calculate aggregated cost of each support window.
5. By using optimization technique we calculate depth of discontinuous areas and reconstruct the body.
The user whole body is extracted by taking the difference between the current video frame and the registered background image.
BACK GROUND SUBTRACTION
Real time compression
• Reconstructed 3d model is very large in size.
• Real-time compression is essential for real-time delivery.
• Modified jpeg compression.
JPEG COMPRESSION
Each block is defined as M[x,y] (i -1) * d <=x < i * d , 0 <= i < w ( j -1) * d <= y < j * d , 0 <=j < h d is the size w width and h height.
For each M[i , j]
• If all M[x, y] == 0 , then M '[i, j] = N .
• If all M[x, y] == 1, then M '[i, j] = A .
• If exists any M[x, y] == 0 and any M[x, y] == 1 , then M '[i, j] = B
Multi-Party Tele-Immersion using internet
Server side
• The TI server provides a virtual environment and room model to divide the users into groups.
• The system information such as user login/logout and their manipulations are written in database.
• The portal provides user login and real-time status display through web browsers with the help of database
Communication model
Hardware Requirements
• 4-core Intel Xeon W3530 processor
• 6GB DDR3 RAM• 2*500GB 7200rpm SATA Hard disk• NVIDIA Geforce GTX 470 display
card
Time delays
Time cost of 3D reconstruction & encoding
Time cost of decoding & rendering
Remote interaction delay on 3D objects
Bandwidth requirement
Applications
• Remote medical diagnosis and therapy.
• Remote and distributed education.• Distributed artistic performance and
interaction.• Virtual travel and tourism.• Automobile Engineering
Challenges
• Quality of transmission affected by high packet loss
• Very Expensive• High bandwidth requirement.• High speed internet is required
(min of 60 MBPS)
CONCLUSION
• Still in its early stages of development.
• Challenges are need to be met.• 3d reconstruction technology
needs to be improved since the reproduced images are jittering.
• Tele immersion technology can surely lead to great developments in the field of communication.
References
• Proposal of Multimodal Communications System Using Tele-Immersion Technology ; IEEE Conference
• Tele-Immersion Environment for Video Avatar Based CVE ; IEEE Conference
• Distance Learning in Tele-Immersion Environment; IEEE Conference
• http://tele-immersion.citris-uc.org• http://graphics.cs.brown.edu/research/telei
THANK YOU