A Realistic Chat Environment for Virtual Avatars in Cyber Space

imminentpoppedIA et Robotique

23 févr. 2014 (il y a 3 années et 1 mois)

51 vue(s)

Graphics Application Lab

A Realistic Chat Environment for Virtual
Avatars in Cyber Space

Cyberworlds ‘08.


Soohyun Park

Pusan National University

Republic of Korea

Graphics Application Lab

2

Motivation


Chat is a crucial function in virtual worlds
.


We need a
realistic and efficient communication
framework
for multi
-
agents participating in a virtual world.

Figure 1. Current Chat System


However, current virtual world
systems have several problems
and limitations.


only 2
-
D dialog boxes
and
word
balloons


All word balloons are
orthogonally visible
to a viewer.


All dialogue texts can be read
by any avatar agent
without
regard to spatial
constraints(distance)
.

Graphics Application Lab

Main Goal


A realistic and efficient communication framework

o
Our virtual chatting system is quite different from current virtual
communicating systems.

o
If an agent wants to talk other people, then that agent should
approach within an ”audible distance”









o
We perceive that some distant agents are chatting, but cannot
identify the text contents clearly due to the distance.

3

Graphics Application Lab

4

Human
-
Cognition in Chat (1)


A virtual chat room consisting of three small subspaces
.


9 virtual chat agents are strolling in the room.


Chat agent
C

in the passageway gate is watching Groups
G
1
, G
2

and Group
G
3
.


(a) at
time
i

(b) at
time
i+1

(c) at
time
i+2

Graphics Application Lab

5

Human
-
Cognition in Chat (2)


Agent
C

is connected to Group
G
1

at
time
i
.

(a)

(b)

(c)

(d)

Graphics Application Lab

6

Human
-
Cognition in Chat (3)


Agent
C

is connected to Group
G
2

at
time
i+1
.

(a)

(b)

(c)

(d)

Graphics Application Lab

7

Human
-
Cognition in Chat (4)


Agent
C

is looking at Group
G
3

at
time
i+2
.

(a)

(b)

(c)

(d)

Graphics Application Lab


Virtual Chat Bandwidth(VCB) for two chat agents
A
a
,
A
b

.

Evaluating Chat Visibility(1)

8


Communication capacity bandwidth



Virtual Chat Bandwidth is computed
dependent on the
distance

and
viewing vector
between two agents.



The higher VCB, the greater the
extent to which two agents A and B
are able to chat with each.


Graphics Application Lab


Difference of viewing result according to the distance.


9

Evaluating Chat Visibility(2)

(a) VCB
A,BC

= 92.764

(b) VCB
A,BC

= 54.720

Chat Pair

l
ab

θ
a

θ
b

VCB

A

B

0.078

90

90

92.7644

A

C

0.078

110

45

75.6165

Chat Pair

l
ab

θ
a

θ
b

VCB

A

B

0.530

90

90

65.3595

A

C

0.525

110

45

54.7203

Graphics Application Lab

Constructing Chat Flow Graph(CFG)


A novel data structure, Chat Flow Graph (CFG)

o
Keeping track of chat dialogue is crucial.

o
Most chat programs provide
only textual history

transcripts

based
on
temporal sequence
without any explicit relationship tag.








o
A smart procedure to
manage the chatting dialogues
among
multiple agents in virtual space.


More flexible and superior to the previous chatting history

10

(a) Textual
history
transcript

(b) Comic Chat

Graphics Application Lab

Constructing CFG (1)


CFG(Chat Flow Graph) Construction Algorithm

11

o
Nodes denote the
messages with
timestamp and agent.

Node

Talk( A
i
, t
i

)
.

o
Edges are determined
through
timestamp

t

and
VCB
due to the
spatial information.




Graphics Application Lab

Experiment


Experiment
: One Group Chat

o
Movie


‘Dead Poets Society’

o
One group including five men is talking in a room


Experiment process

o
calculating VCB, constructing CFG, optimizing parameters and
improving CFG

12

Graphics Application Lab


The Movie ‘Dead Poets Society’


13

Chat Pair

l
ab

θ
a

θ
b

VCB

A

B

0.010

145

145

57.352

A

C

0.010

45

120

78.246

A

D

0.010

75

100

97.522

A

E

0.020

105

90

98.242

B

C

0.020

110

110

93.932

B

D

0.020

90

90

99.960

B

E

0.010

45

80

83.440

C

D

0.010

150

100

70.164

C

E

0.020

90

110

96.899

D

E

0.020

65

135

80.021

Experiment for One Group (1)

(b) VCB among agents appeared
in Figure (a)

(a) Scene of movie and
Visibility graph

Graphics Application Lab


Chat Flow Graph of Talk shown in the movie ‘Dead
Poets Society’
.

14

Experiment for One Group (3)

o
Threshold parameter
δ = 15

o
Easier for people to understand
the chat flow than before.

o
More flexible and superior to
previous chat text, which is only
kept in terms of temporal
sequence without any information
about question/answer pairing
tags.

Graphics Application Lab

Conclusion


Conclusion

o
We proposed a
realistic communication
framework
and a nice algorithm to
cluster a set of dialogue text

by
considering the spatial information
of chat agents.

o
We hope this method would be applied to the internet
chat system over virtual reality space.

15