APPLICATION OF MULTIMEDIA

MULTIMEDIA APPLICATIONThe categories are:-I. Interpersonal communications

II. Interactive applications over the internet

III. Entertainment applications

I. Interpersonal Communications

It involves speech, image, text or video.

Some case having single medium & some are having two or more medium

(A) Speech only

ANALOG OR DIGITAL CIRCUIT

PSTN OR ISDN

Private site-wide telephone N/W

Interpersonal communications involving speech-telephone have been provided by using telephone which are connected either through PSTN or ISTN or PBX.

The user can also take part in telephone call through pc.

It requires a telephone interface card & associated s/w is known as computer telephony integration(CTI)

Addition to telephony, many public and private networks supports additional service for ex- voice-mail & teleconferencing.

Voice mail is used in the event of the called party being unavailable.

A spoken message can then be left in the voice mailbox of the called party. This is located in voice-mail server. The message can be read by the owner of mailbox the next time when he contacts the server. Teleconferencing calls involve multiple interconnected telephones/PCs. Each person can hear and talk to all of the others involved in the call.

This type of call is known as conference call

It requires a central unit known as an audio bridge which provides the necessary support to set up a conference call automatically.

Internet is used to support telephony (support PC to PC telephony)

In case of pc to pc telephone call the address that are used to identify individual computers connected to the internet are used in the same way as for data transfer application.

Internet operates in a packet mode, both PC must have necessary H/W & S/W to convert speech signal from microphone into packets (input) & vice versa(output)

Telephony over internet is known as packet voice & network protocol associated with internet is internet protocol. Hence it is voice over IP(VOIP)

SITE/CAMPUS LAN GLOBAL INTERNET

ISP N/W

PACKET MODE

PACKET MODE

CIRCUIT MODE

CIRCUIT MODE

PSTN/ISDN

(TELEPHNY OVER THE INTERNET)

When a pc connected to the internet needs to make a call to a telephone that is connected to PSTN/ISDN, or both are operate on circuit mode an interworking unit i.e.-telephone gateway is used.

PC user first sends the request to make a (telephone) call to a reallocated telephony gateway using the internet address.

Then assuming the user is registered to use this service the gateway requests from the source pc the telephone number of the called party. The4 source gateway initiates the session (call) with telephone gateway nearest to the called party using the internet address of the gateway.

The called gateway then initiates a call to the recipient telephone using its telephone number & call setup procedure of PSTN/TSDN.

This procedure will continue till the completion of the course.

(B). IMAGE ONLY

PSTN/ISDN

ANALOG TO DIGITAL ACCESS

PC-FAX

(IMAGE-ONLY) We can exchange electronic image of documents over PSTN or ISDN. This service is known as facsimile (fax).

This communication involves a pair of fax machine one at each network termination point.

To send a document the telephone number of recipient & a circuit is setup through the network.

Two fax machines communicates with each other to establish operational parameters after which the sending M/C starts scan & digitize each page of document.

Both fax machines have an integral modem within them & as page is scanned its digitized image is simultaneously transmitted over the network & as this is received at the called side a printed version of document is produced.

After the last page of the document has been sent & received the connection through the network is cleared by the calling machine.

We can also use pc instead of fax machine to send an electronic version of document ie. Stored directly within pcs memory. ( this is known as PC FAX)

The digital image of each page of the document is sent in the same way as the scanned image produced by fax machine.

It requires a telephone interface card & software

The terminal at the called side is either fax machine or a similar PC.

( C ) TEXT ONLY

`

ENTERPRISE-WIDE PRIVATE NETWORK

Access Via either PSTN OR ISDN

GLOBAL INTERNET

ISP NETWORK

DESKTOP PC

SITE/CAMPUS LAN

(EMAIL TRANSFER)

Both email server & internetwork gateway operate using standard internet communication protocol. The head contain name of both sender & receiver of mail.

It also contain a copy of mail can be sent to multiple recipients each of whom is listed in CC part of mail header.

It contains subject & date.

Contents of text-only mail comprise unformatted text, typically shins of ASCII characters.

control:HEADER FIELDS

BODY OF MESSAGE CONTACT

(Mail message format)

D. Text and images

Stored White bound Program

Enterprise-wide Private N/W,LAN,INTERNET

(STORED/ WHITEBOARD/WORKSPACE)(TEXT & IMAGE COMPUTER SUPPORTED COOPERTIVE WORKING)

(CSCW)

Text & images integrated together is computer supported cooperative working (CSCW).

HERE THE USER TERMINAL IS PC & a window on each persons display is used as a stored workspace.

This is known as shared whiteboard & normally the display comprises text & images integrated together.

The s/w associated with CSCW is a central program known as whiteboard program & linked set of support programs one in each pc.

The program is made up of two parts i.e a change-notification part & and update-control part.

Whenever the member of the groups updates the contents of white board the change-notification part sends details of changes to white board program

This relay the changes to the update-control in each of the other pcs & those in turn proceeded to update the contents of their copy of white board.

(This is used when Distributed group of people are working on same project but resides in different locations)E. speech and video The application that uses speech and video integration together is video telephony. In office a single multimedia PC is used to provide the videophone service together with a range of other services. PC is attached with a video camera in addition to the microphone and speaker used for telephony. The moving image of the called party is displayed in a window of pc screen. The network must provide a two- way communication channel between the two parties. The integration of video with speech requires more bandwidth. As with telephony a call may involve not just two persons but several people located at their own with separate PC.

This type of call is known as desktop video conferencing call.

Large corporations of this type have an enterprise-wide network to link the sites together & in order to support video conferencing there is a centered unit called multipoint control unit(MCU). Sometimes video conferencing server associated with this network.

(a). PSTN/ISDN/INTERNET/LAN Enterprise network

Multimedia PC with video Camera

Microphone & Speaker.

Two Simultaneous integrated speech and video information stream

(Two Party Video Telephony Call)(b). PSTN/ISDN/Enterprise network

MULTIMEDIA PC WITH VIDEO

CAMERA MICROPHONE AND SPEAKER

Two Simultaneous integrated speech and video information streamPRINCIPLE

Here each separate window on the screen of each participants pc should be used to display the video image of all the other participants.

It requires multiple integrated speech-and-video communication channels, one for each participant being sent to each of other participants.

It requires more bandwidth. The integrated speech-and-video information stream from each participant is sent to the MCU which then selects just a single information stream to send to each participant. Whenever MCU detects a participant speaking it relays the information stream from the participant to all other participants.

LAN & Internet support multicasting. i.e. all transmission from any of the pc belonging to a predefined multicast group are received by all other member of the group.

Hence the network support multicasting can hold conferencing session without on MCU. This is possible when only a limited number of participants are involved owing to high load it places on the network. In some application involves only a single person at each location & in some other application not involve groups of people at one or more of the locations.

Two way simultaneous integrated speech and video information streams from all parties

(Video conferencing using a broadcast network) A person at one location is communicating with a group of people at another location.

Ex- transmission of a live lecture or seminar.

The information stream transferred from the lecturer to the remote class would be integrated speech-and-video together with electronic copies of transparencies & other documents used in lecturer.

In reverse direction the lecture can see & hear the members of the class at remote location.

This is similar to two party video telephony call. If the lecturer being relayed to multiple locations either a separate communication channel is required to each remote site or an MCU is used at the lecturers site.

For high bandwidth network is involved; the network is either ISDN which support multiple 64kbps channel or broadband multiservice network.

REMOTE LECTURER

VIDEO CONFERENCE STUDIO

b. ISDN/Broadband network/ dedicated circuit network


VIDEO CONFERENCING SYSTEM


VS=Video Confercing System

MCU= Multipoint Control Unit.

(MULTIPARTY VIDEO CONFERENCING)

In picture(b) a group of people at each location.

A group of people present at each location in specially equipped room called video conferencing studios. Which contain all the necessary audio & video equipment. This comprises one or more video cameras, large screen display & associated audio equipments All of this is connected to a unit called video conferencing system.

In conference of multiple location on MCU is normally used to minimize bandwidth demands on the access circuits to the network.

The MCU is shown as a central facility within the network and hence only a single two-way communications channel is required for each access circuit of the network.MULTIMEDIA

E-mail message consist of text only but mail containing other media types such as images, audio & video are also used.

Examples of email other than text are voice mail.

VOICE-MAIL

In internet-based voice mail, there is a voice-mail server associated with each network.

The user first enters a voice message addressed to the intended recipient and the local voice-mail server then relays this to the server associated with the intended recipients network.

The stored voice message is then played out the next time the recipient accesses are used for video-mail.

MULTIMEDIA MAIL

Here the textual information is annotated with a digitized image, a speech message or video message.

In case of speech-and-video, the annotation can be sent either directly to the mailbox of the intended recipient together with the original textual message and hence stored & played out in normal way or they may have to be requested specially by the recipient when the textual message is being read.

The recipient can always receive the basic text-only message but the multimedia annotations can be received only if the terminal being used by the recipient supports voice and/or video.

Sent initially

Sent on request

II) INTERACTIVE APPLICATIONS OVER THEINTERNET

World Wide Web (www) or Web Server comprises a linked set of multimedia information servers that are geographically distributed around the internet.

The total information stored on all the servers is equivalent to vast library of documents. Each document comprises a linked set of pages and the linkages between the pages are known as hyperlinks.

These are pointers/ references to the documents.

The reader of the document has option at well-defined points throughout the pages, to jump a different page of same document or to different document.

The optional linkage points within documents are defined by the creator of the document which is known as anchors.

Documents Comprising only text are created using hypertext & those comprising multimedia information are created using hypermedia.

Anyone can create a new documents of a particular server site-providing the server has been allocated an internet address and make hyperlink references from it to any other document on the web.

Each document has a unique address known as Uniform Resource Locator(URL) Which identifies both the location of the server on the internet where the first page of the document(homepage) is stored.HYPERMEDIA AND HYPERTEXT

Hypermedia is a style of building systems for organizing structuring and accessing information around a network of multimedia nodes connected together by links.

The hypermedia document may include a large amount of index text which are linke to some other documents.The hypermedia systems can distinguish into generations as follows:-

I. first generation hypertext system were mainframe based, text only ststems for augmenting the performance of information processing environment, storing the whole worlds literature of for supporting traditional writing and reading.

II. Transition from hypertext to hypermedia took place with the second generation systems. These systems were quite similar in concept with first generation hypertext systems, but they were workstations and PC based, with more sophisticated graphics intervace and support to other forms of information such as graphics, sound, animation, video.

A. Data Model

Nodes are the primitive unit for organizing information in hypermedia network.

Nodes function as collections of primitive instructors of data which are bind together in order to provide a coherent information abstraction to existing information space.

Links implement the direct interconnections between. They are anchored to a departure node and provide the hypermedia user the ability to activate them and move to the destination node.

Links are associated with parts of departure nodes rather than with the node as a whole. (HYPERMEDIA GRAPH)

B. PROCESS CUBMODEL

Navigation is the primary means of access information in hypermedia network. The basic characteristics of navigational access are that users navigate by self motivation without having any external navigation aid.

We can also backtrack to the previously visited node.

HYPERMEDIA STRUCTURE The property of hypermedia is non-linear information system.

Here nodes may contain sound, graphics, text and other related information. While links are connection between the conceptual elements.

The hypermedia structure may be divided into three layers, i.e. the runtime, storage and within component layer.

The runtime layer is concerned with final presentation of documents.

The within component layer contains the nodes or the atomic container of the media objects inside document.

This layer represents the individual items contained in the document.

The storage layer provides the hypertext structure of a document.

Presentation specification

anchoring

(Hypermedia layer)

The storage layer is related to the within component layer through anchoring which enables media type independent linking of media content.

The presentation specification layer defines how the contents of the storage.

At the upper layer, the presentation layer, all the functions connected to the user interface are embedded. Here nodes links are mapped to the parts of the document are visualized. The storage layer define the overall structure of the document itself, independent of the documents presentation or the storage of its content

----------------------------------------------------------------------------------------------------------------------------------DIGITAL LIBRARIES

Though digital library we can access information online.

All information stored in such libraries is in digital form.

Multimedia documents are an integral part of the digital library concept.

Text-based information may be available as formatted or unformatted text files.

Older documents are made available by scanning the pages as still images and transmitting them as image file.

Publishing & library management functions can be combined. Almost all aspects of publishing can be done via networks.

Authors can submit the electronic version of script to the publisher.

PC

PC

Telephone

Telephone

phone

Cellular phone network

Audio bridge

Voice mail server

PBX

Telephone

Telephone

Telephone

PC

Telephone

PC

PC

PC

POCKET N/W

POCKET N/W

PC

Telephone N/W

Telephone N/W

PC

PC

PC

Telephony Network

PC

Telephone

Telephone

Telephone

FAX MACHINE

FAX MACHINE

PC

FAX MACHINE

PC

PC

PC

PC

E-MAIL

SERVER

PC

PC

GATE WAY

PC

G/W

Email server

Email server

G/W

SMALL BUSINESS

PC

PC

PC

PC

Update Control

Change Notification

PC

PC

PC

PC

Multipoint control Unit (MCU)

PC

PC

Network

Pc

PC

PROJECTOR

SPEECH,VIDEO & IMAGE

SPEECH ONLY OR SPEECH & VIDEO

CAMERA

VS

VS

MIC

VS

VS

mcu

Mail Header

Hi ABC

Click on the following

Speech part

Image part

Video part

Speech Part

Image Part

Video Part

NODE

C

NODE

B

NODE

A

NODE F

NODE E

Link

Link

Link

Link

Link Link

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Runtime

Storage

Within component