XCEL NOTES AND PROGRAMS

LECTURE NOTES FOR COMPUTER SCIENCE STUDENTS

THEORY

C++

Computer Graphics

JAVA

XML

PROGRAMS

C Programs

C++ PROGRAMS

JAVA PROGRAMS

Computer Graphics PROGRAMS

Data Structures PROGRAMS

Operating System Programs

General Knowledge

Questions and Answers

Aptituted

C

C++

JavaScript

VIDEO CONFERENCING

VIDEO CONFERENCING
Video conferencing is the use of visual and audio technology to enable people in different locations to communicate, as if they were in the same room, through the use of cameras, monitors or screens. Participants in such a meeting can also share documents, spreadsheets and images, depending upon the quality of the network links and the equipment used.

TYPES OF VIDEO CONFERENCING
THERE ARE THREE MAIN TYPES OF VIDEO CONFERENCING SYSTEM
1. DESKTOP

2. SET-TOP

3. INTEGRATE DESKTOP VIDEO CONFERENCING

This form of video conferencing has rapid growth and is designed for use by individuals, as a small screen on the desk is used. it is now possible to display images for up to participants, using high quality video, excellent voice communication and integrated document and application sharing. This form of video conferencing is also available on laptops, which provide a mobile communication platform.
SET-TOP VIDEO CONFERENCING
These are compact video conferencing units. They consist of a camera, which can pan, tilt and zoom, a microphone and are designed to sit on top of a monitor. For added flexible use in different locations within a building, they can also be used on a purpose built roll about unit. These systems are usually used for small groups of people. They provide a high quality visual and audio meeting facility, which can be enhanced with the use of additional presentation equipment.

INTEGRATED VIDEO CONFERENCING

These are video conferencing systems that are generally built into larger rooms, such as board rooms and conference rooms. they are a highly professional communication facility and can provide a variety of presentation displays, depending upon the equipment used. Typically, they are used for groups of ten or more people. All of these different types of video conferencing units and systems can link to each other, to provide a variety of mediums for people to communicate, either within an organisation or externally.

VIDEO CONFERENCING
• Reduce Travel Costs

• Accelerate Decision Making

• Provide Enhanced Control Of Projects

• Improve use Of Executive Time

• Provide Cost-Effective Training to Remote Locations

• Be Used as a Medium to Conduct Interviews

• Reinforce Close Relationships with Suppliers, Clients and Remote Staff

• Can be Stored in DVD

INDEX PAGE

LECTURE NOTES FOR COMPUTER SCIENCE STUDENTS

THEORY

C++
Computer Graphics
JAVA

PROGRAMS

C Programs

C++ PROGRAMS

JAVA PROGRAMS

Computer Graphics PROGRAMS

Data Structures PROGRAMS

CG INDEX PAGE

COMPUTER GRAPHICS

Overview Of Graphics System

Refresh Cathode Ray Tube

RANDOM SCAN DISPLAY

Raster Scan Display

Color CRT Monitors

Direct View Storage Tube

LIQUID CRYSTAL DEVICES

RASTER SCAN SYSTEMS

Input Devices

DDA LINE DRAWING ALGORITHM

BRENHAM’S LINE DRAWING ALGORITHM

BRENHAM’S CIRCLE DRAWING ALGORITHM

CLIPPING

VIEDO CONFERENCING

MULTIMEDIA COMMUNICATION SYSTEMS

MULTIMEDIA COMMUNICATION SYSTEMS (MCS)
Multimedia Communication Systems into Two Architectural
Subsystems APPLICATION SUBSYSTEMS TRANSPORT SUBSYSTEMS
1. APPLICATION SUBSYSTEMS

1.1. COLLABORATIVE COMPUTING

Know as Computer Supported Cooperative Work(CSCW) Provides Network Connectivity and End-Point Integration Collaborative Dimensions Partitioned into Three Dimensional space with 3 Parameters

1. TIME

2. USER SCALE

3. CONTROL

TIME Synchronous - Happen at same TimesAsynchronous - do not happen at same time

USER SCALE SINGLE USER MULTIPLE USER Static- Pre – determined members in group members does not changeDynamic- group members can join or leave the activity at any timeHomogeneous- same characteristicsHeterogeneous- different characteristics

CONTROL Centralized- main manager who controls the team and team reports to himDistributed- every group members has control over his/her own task

DIMENSION OF COLLABORATIVE COMPUTING

GROUP COMMUNICATION ARCHITECTURE Group communication architecture consists of Support Model System Model Interface Model

• GROUP RENDEZVOUS Group rendezvous denotes a method which allow one to organize meetings, get information about the group, ongoing meetings etc., groups are static, dynamic, synchronous, asynchronous
• SHARED APPLICATION Shared application denotes techniques which allow one to replicate information to multiple users simultaneously.

TWO TYPE ARCHITECTURE
1. CENTRALIZED ARCHITECTURE

2. REPLICATED ARCHITECTURE
Centralized Architecture

A single copy of shared application runs at one site Replicated Architecture A copy of the shared application runs locally at each site
picture 10-3
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• CONFERENCING
This service provides the management of multiple users for communicating with each other using multiple media.
Conferencing two types
1. CENTRALIZED CONFERENCE CONTROL

2. DISTRIBUTED CONFERENCE CONTROL
Centralized Conference Control
Establishment of conference by an initiator and initiator selects the group of conference members.ADVANTAGE- Guarantees consistency of conference state DISADVANTAGE- New participant want to enter causes large delay
Distributed Conference Control
The initiator of the conference establishes a multicast space, with multicast entries for distribution of information to the conference participants and conference is established