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A

Seminar Report on

VIDEO CELL PHONES

Prepared by

ROSY J. SINGH

Guide: Ms. AVANI PATEL

Department of Electronics Engineering

Sarvajanik College of Engineering & Technology

Dr. R K Desai Marg, Athwa Lines, Surat.


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A Seminar Report on

VIDEO CELL PHONES

Prepared by : Rosy J. Singh

Roll No. : 51

Class : B.E.IV (Electronics Engineering) 8th Semester

Year : 2001-2002

Guided by : Ms. Avani Patel

Department of Electronics Engineering.

Sarvajanik College of Engineering & TechnologyDr R.K. Desai Road,

Athwalines, Surat - 395001,India.


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ACKNOWLEDGEMENT

Many have contributed to the successful completion of this report. I

would like to place on record my grateful thanks to each of them.

Ms. Avani Patel, my guide, has helped me immensely throughout

the research. She has also helped in reading, modifying and correcting

the report.

I am also indebted to the staff and members of Electronicsdepartment of SCET for their assistance.


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ABSTRACT

Cell phones have been the wave of our future for some time now.

More than 100 million cell phones are in use in the World today, and it will rise to

more than 200 million by 2003 according to International Data Corp.'s (IDC) mostrecent estimates. Every year they get better and smaller, but what else can the

cellular phone companies do in order to improve or upgrade it?

Video cell phones have been introduced to be the next generation (third

generation) of cell phone history. Samsung Electronics and Geo Interactive Media

Group announced that they have developed the first video cell phone successfully in

November of 2000.

The seminar aims to analyze how the video cell phone works, and what

are the requirements for example MPEG4, bandwidth, etc. Basically,it deals with

the following three requirementsthe wireless network needed,the hardware and

finally the video code required. It also studies the first working cellphone

produced by Samsung and GEO using the A2 chip.


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INDEX

1.Introduction

2.The evolution of mobile communication

3.3G technology

3G Features

3G Talking Points

3GReady or not?

3GVideo on Mobile

Video on mobilesome innovative applications

First video cell phone4. Wireless networks

Overview of some wireless systems

CDMA,TDMA & GSM

Improvements needed for the wireless network

CDMA 2000-Delivering on 3G

CDMA Deployments

CDMA-Migration5.Hardware

A2 ASIC Chip

Working of A2

Features of A26.Video Code

Video code

MPEG-4

MPEG Architecture

MPEG-2 V/s MPEG-4Conclusion

Bibliography

0102

0507080910

10

121314151516

182021

2425293132

33


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1. INTRODUCTION

More than a decade ago, Martin Cooper invented a product that has

become ubiquitous in modern lifethe CELLPHONE. However, initially it

was huge and heavy. The connection and reception of the network was also

bad. At that moment, cell phones were not a necessity and they were mostly

owned by wealthy people, business people, and important authoritative

figures. As time went by, technology improved, and the cell phone began

getting smaller, cheaper and better. Nowadays, almost everyone has a cellphone. The functionalities of the cell phones increased also. It not only works

as a phone, it has clock, alarm, games, calendar, notes, reminder features,

online capabilities etc. This stage of cell phones was the second generation

cell phone.

Video has emerged as the latest obsession in the high-tech world The

third generation cell phone have the video function added to the it. Therefore,

people can not only send text messages, they will also be able to send a video

message to their friends, families, co-worker, classmate etc.

This report briefly describes what the requirements of the video cell

phone are. There are three main points that people should be working on for

the video cell phone: the wireless network requirement, the hardware needed,

and the kind of video code that should be used. It is divided into various

chapters starting from the evolution of mobile communication,then covering

the various aspects of 3G phones, and finally dealing with the details of the

requirements of video cellphones.


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2. THE EVOLUTION

OF

MOBILE COMMUNICATION

The mobile communications industry has evolved in three stages:

Three generations of mobile phones have emerged so far, each successive

generation more reliable and flexible than the last:

Analog: You could only easily use analogue cellular to make voice calls, and

typically only in any one country.

Digital mobile phone systems added fax, data and messaging capabilities as

well as voice telephone service in many countries.

Multimedia services add high speed data transfer to mobile devices, allowing

new video, audio and other applications through mobile phones- allowing

music and television and the Internet to be accessed through a mobile

terminal.

With each new generation of technology, the services which can de deployed

on them becomes more and more wide ranging and truly limited only by

imagination.

ANALOG DIGITAL MULTIMEDIA


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During the first and second generations different regions of the world pursued

different mobile phone standards, but are converging to a common standard for

mobile multimedia called Third Generation (3G) that is based on CDMA technology.Europe pursued NMT and TACS for analog and GSM for digital, North America

pursued AMPS for analog and a mix of TDMA, CDMA and GSM for digital. 3G

will bring these incompatible standards together

The International Telecommunications Union(ITU) took the initiative to

unify the disparate standards employed by various countries.The initiative was in the

form of International Mobile Telecommunications 2000,also called as 3G.

IMT 2000 provides a framework for worldwide wireless access by linking

diverse terrestial and satellite based networks,mobile communication technologies

and systems for fixed wireless access.The goal-to fulfil the dream of anywhere

,anytime communication.

Following on the heals of analog and digital technology, the Third

Generation will be digital mobile multimedia offering broadband mobile

communications with voice, video, graphics, audio and other information. This

transition is shown in Table below:


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Genera

tionType Time Description

1st Analog 1980s Voice centric, multiple standards (NMT,TACS etc.)

2nd Digital 1990sVoice centric, multiple standards (GSM,

CDMA, TDMA)

2.5

Higher

Rate

Data

Late1990s

Introduction of new higher speed data

services to bridge

the gap between the second and Third

Generation,

including services such as General Packet

Radio Service

(GPRS) and Enhanced Data Rates for Global

Evolution (EDGE)

3rd

Digital

Multime

dia

2000s

Voice and data centric, single standard with

multiple

Modes

3. 3G TECHNOLOGY


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3G Features

3G has the following features:

Packet everywhere:

With Third Generation (3G), the information is split into separate but related

packets before being transmitted and reassembled at the receiving end.

Packet switched data formats are much more common than their circuit switched

counterparts. Other examples of packet-based data standards include TCP/IP, X.25,

Frame Relay and Asynchronous Transfer Mode (ATM). As such, whilst packet

switching is new to the GSM world, it is well established elsewhere. In the mobile

world, CDPD (Cellular Digital Packet Data), PDCP (Personal Digital Cellular

Packet), General Packet Radio Service (GPRS) and wireless X.25 technologies have

been in operation for several years. X.25 is the international public access packet

radio data network standard.

Internet Everywhere

The World Wide Web is becoming the primary communications interface-

people access the Internet for entertainment and information collection There is a

trend away from storing information locally in specific software packages on PCs to

remotely on the Internet.Hence, web browsing is a very important application for

packet data.

High Speed:

Speeds of up to 2 Megabits per second (Mbps) are achievable with Third

Generation (3G). The data transmission rates will depend upon the environment the

call is being made in- it is only indoors and in stationary environments that these

types of data rates will be available. For high mobility, data rates of 144 kbps are


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expected to be available- this is only about three times the speed of todays fixed

telecoms modems.

New ApplicationsBetter Applications:

Third Generation (3G) facilitates several new applications that have not

previously been readily available over mobile networks due to the limitations in data

transmission speeds. These applications range from Web Browsing to file transfer to

Home Automation- the ability to remotely access and control in-house appliances

and machines. Because of the bandwidth increase, these applications will be even

more easily available with 3G than they were previously with interim technologies

such as GPRS.

Service Access:

To use Third Generation (3G), users specifically need:

A mobile phone or terminal that supports Third Generation (3G)

A subscription to a mobile telephone network that supports Third Generation

(3G)

Use of Third Generation (3G) must be enabled for that user.Automatic access

to the 3G may be allowed by some mobile network operators, others will

charge a monthly subscription and require a specific opt-in to use the service

as they do with other nonvoice mobile services

Knowledge of how to send and/ or receive Third Generation (3G)

information using their specific model of mobile phone, including software

and hardware configuration (this creates a customer service requirement)

A destination to send or receive information through Third Generation (3G).

From day one, Third Generation (3G) users can access any web page or other

Internet applications- providing an immediate critical mass of users.

These user requirements are not expected to change much for the meaningful use

of 3G.


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3G Talking Points

The telecommunications world is changing as the trends of media

convergence, industry consolidation, Internet and IP technologies and mobile

communications collide into one. Significant change will be bought about by this

rapid evolution in technology, with Third Generation mobile Internet technology a

radical departure from that that came before in the first and even the second

generations of mobile technology. Some of the changes include:

People will look at their mobile phone as much as they hold it to their ear. As

such, 3G will be less safe than previous generations- because television and

other multimedia services tend to attract attention to themselves- instead of

hands-free kits, we will need eyes-free kits!

Data (non-voice) uses of 3G will be as important as and very different from

the traditional voice business

Mobile communications will be similar in its capability to fixed

communications, such that many people will only have a mobile phone

The mobile phone will be used as an integral part of the majority of peoples

lives- it will not be an added accessory but a core part of how they conduct

their daily lives. The mobile phone will become akin to a remote control or

magic wand that lets people do what they want when they want

3G technologyready or not?

Third-generation wireless technology finally seems to be arriving. South

Korea and Japan have it and even in the United States, there are signs of progress. So

where, as this rush to robustness picks up steam, is the granddaddy of all high-end

mobile applications -- streaming multimedia?


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Asia and Europe remain ahead in wireless adoption across the board, and the

slickest new services will be old hat in Tokyo by the time American consumers get a

hold of them.

In Korea, there is tremendous experimentation with all types of multimedia.Japan has seen a huge hit with messaging of still images and video is right around

the corner. Japanese service provider J-Phone unveiled a service earlier this year that

allows digital images, taken with digital cameras or cameras built into some models

of phone, to be shared among friends.

Streaming media is supposed to be the killer application for 3G.The

deployments of CDMA2000 1X by Sprint, Verizon and Canada's Bell Mobility can

start to do the trick. It has an advertised data rate of up to 144 kbps,More likely that

rate will actually be 40 to 60 kbps, and video is clearly viable in those ranges.

3G--Video on mobile-Who wants it?

Who's going to want to watch video on a mobile device? it prompted a survey

of streaming video advocates and observers.

Is video on mobile more likely to capture the hearts of suited executives --

ever alert for the next new thing -- or the imaginations of the unwashed masses who

just want to have fun. The answers are different depending on which quadrant of the

globe you're standing on, of course.

Mobile video is already off and running in Japan, with NTT DoCoMo's

announcing a new platform that provides "one-to-many" live video distribution to 3G

(third generation) handsets.

It delivers streaming media using MPEG-4 technology -- is the first of its

kind. It was developed with U.S.-basedPacketVideo.
http://www.nttdocomo.com/http://www.nttdocomo.com/http://www.packetvideo.com/http://www.packetvideo.com/http://www.nttdocomo.com/http://www.packetvideo.com/


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It is not expected that people will watch 10 or 15 or a half hour of a

television program on their mobile device, because you can get that on television and

it's not really that interesting [on a mobile], but what is expected is to break out the

15- and 20-second jokes, the pratfalls or the explosions, and put them in an

environment where people can send them to friends.

There are certain sports where audio just won't deliver the full experience.

Also, music video has substantial value to consumers -- there are business models

where people will pay for videos.

News is another really good example. A video capable cell phone would

allow users to see Internet free stock tickers, sports scores and eventually each other

though two-way video conferencing--- no typing, logging in or passwords required.

These are just a few of the uses that a video cellphone can be put to.

Video on mobileInnovative Applications

The text-messaging craze has swept Europe and Asia.Handset makers and

carriers are beginning to talk about MMS, the multimedia messaging service that isthe natural outgrowth from text-only SMS, or short message service. Popular early

applications are more likely to be users' own creations. when people are walking

around town, they can subscribe to certain topics,So when you're walking around

New York, videos associated with the exact area where you happen to be standing or

walking at the time will pop up. For instance, you're doing a tour of Washington,

D.C., and you go by the Reflecting Pond, and up comes the Martin Luther King ['I

have a dream'] speech, which you can see right where you are. Sort of like a video

time capsule.

Specific lifestyle applications: Some unusual examples-


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Imagine putting the yoga teacher in your pocket, putting the professional chef -- you

know, 'How do I make this meal?' -- Well, a housewife doesn't have a computer in

her kitchen, but if she has her cell phone, being able to see 10 step-by-step 15-second

[segments] of how to cook a gourmet meal -- that's something she can use and will

use.

The First Video Cellphone

StarTrek style science fiction is to become a mainstream reality for the many

millions of people who are leading increasingly cellular-centric professional and

personal lives, with the introduction of world's first ever MPEG4 streaming video

cell-phone based on GEO's EmblazeTM A2 video ASIC chip by Samsung Korea. The

phone represents a breakthrough in cellular technology enabling the playback of

streaming video content over GSM and CDMA based IS-95B and IS-95C networks.

The new phone allows users to view rich media content directly on their

mobile phones by simply pressing the video function key and browsing through the

list of available content, in a similar fashion to TV channels

The phone enables varying viewing experiences (video size, speed and image

quality) according to the bandwidth provided by the network over 2G, 2.5G and 3G

technologies.

As bandwidth increases, the user can enjoy larger video size with a smoother

image and better image quality.

The phone is currently compatible with existing CDMA systems at speeds of

9.6kbps (IS-95A), 64kbps (IS-95B) and CDMA2000 1X that is capable of reaching a

data transfer rate of up to 144Kbps.
http://www.cellular.co.za/cdma.htmhttp://www.cellular.co.za/cdma.htm


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The EmblazeTM A2 video ASIC chip has created a revolution by enabling

video playback over standard devices using standard battery technology, memory

and processors what was formally deemed as impossible by world engineers.

The device will allow people to receive and play video from the Internet and fromemail.

What has been holding back other companies from creating similar products

is the fact that "third generation," or 3G, networks are still years away. With its much

higher bandwidth, 3G systems are expected to enable many new wireless

applications, including full-motion video. But Samsung and Geo assert that current

wireless networks can support their video phone.

4. WIRELESS NETWORK

Among the three requirements, it is widely believed that the technology of

wireless network has to improve first. This is because people believe that video cell

phones are not possible in the second generation network. Second generation

network, 2G, basically includes Code Division Multiple Access (CDMA), Time

Division Multiple Access (TDMA), and Global System for Mobile communication

(GSM).

Overview of some wireless systems:

1981:NMT-450

1986:NMT-900 1983:AMPS

1991:D-AMPS


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NMT: Nordic Mobile Communication

Developed by Denmark,Norway,Finland & Sweden.Uses 450 & 900 Mhz

carrier.

AMTS: Advanced Mobile Phone System

It is an anlog system.Works at 800 Mhz.

PDC: Personal Digital Cellular

Used mainly in Japan.

UMTS: Uniform Mobile Telecommunications system

Is the European proposal for IMT-2000 prepared by ETSI.It represents an

evolution from 2nd generation GSM system to the 3rd generation system.

1992:CSM

1994:DCS 1800

1991:CDMA

1993:PDC

2005?UMTS/IMT-2000


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CDMA,TDMA & GSM:

TDMA: is a method of utilizing radio spectrum. It provides each user access

to the entire frequency channel for a brief period, during which the user

transmits data. The users' frequency channel is shared with other users who

have time slots allocated at different times.

GSM :is an international, non-proprietary system that is constantly evolving.

GSM uses digital technology and TDMA methods to transmit the data. Voice

is digitally encoded via a unique encoder, which emulates the characteristics

of human speech.

CDMA: is a "spread spectrum" technology, which means that it spreads the

information contained in a particular signal of interest over a much greater

bandwidth than the original signal.

Spread spectrum involves spreading the bandwidth needed to transmit the

data,which causes an increase in resistance to narrowband interferance.All

narrowband signals are spread into broadband using same frequency range.all

senders use the same frequency band.

To separate different channels,CDM is used.The spredaing is achieved by

using a special code.The techniques used areDirect Sequence Signal

Spreading(DSSS) and Frequency Hopping Spectrum Spreading.Each channel is

allocated a code which the receiver has to apply to recover the code.Without

knowing the code, the signal cannot be recovered and behaves as background noise.


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Frequency are scarce resource around the world.Spread spectrum allows an

overlay of new techniques at exactly same frequency at which the current

narrowband signals operate.This is done for the US Mobile phones systems.While

the frequency around 850 Mhz is already in use for TDM & FDM(AMPS & IS-

54),the CDM(IS-95) is still possible.

Improvements Needed For The Wireless Network

In the second generation network, the transmit rate is slow. In 1993, the first

standard CDMA IS95-A had been completed. Six years later, in July of 1999,

CDMA2000 had been standardized. A few months later, the speed of CDMA had

been increase to 64 kilobits per second (kbps). And by April of 2000, CDMA2000

1X had been introduced. The speed of CDMA had been increased to 144kbps.

However, in November of 2000, the wireless networks could only support 10 to 20

kbps, but streaming video would require much higher bandwidth than this.

Therefore, if one wanted to transfer a video data, the speed of the network would not

be enough.

In 2001, one could say that the network was between the 2G and 3G network.

The 3G network is a broadband, packet-based transmission of text, digitized voice,

and video. It is also a multimedia at data rates up to and possibly higher than 2

megabits per second (Mbps). This offers a consistent set of services to mobile

computer and phone users no matter where they are located in the world.

Why does the network speed need to improve in order to have a video cell

phone? As discussed before, streaming video needs higher bandwidth to transfer the

video data. If the network is not improved, the wireless network cannot provide

quality videos or images even if a video cell phone exists in the current network

status. As a result, 3G network is being developed now.

CDMA2000: Delivering on 3G


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CDMA2000 is an ITU-approved, IMT-2000 (3G) standard. IMT,previously called

Future Land Mobile Telecommunication system) that allows for terminal and user

mobility supporting the idea of universal personal telecommunication(UPT).

CDMA2000--Deployments

The first 3G networks to be commercially deployed were launched in Korea in

October 2000 using CDMA2000 technology.


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The CDMA2000 evolution path is flexible and future-proof...

CDMA IS95-A CDMA IS95-B CDMA2000 1X CDMA2000IXEV

Voice

Data up

to 14.4

Kbps

Voice

Data up

to 115

Kbps

2x

increases

in voice

capacity

Up to

307

kbps*

packet

data on a

single

(1.25

MHz)carrier

First 3G

system

for any

technolo

gy

worldwi

de

Optomiz

ed, very

high-

speed

data

(Phase 1)

Up to

2.4Mbps

* packet

data on a

single

(1.25MHz)

carrier.

Integrate

d voice

and data

(Phase

2); up to

4.8 Mbps

CDMA2000 is a family of technologies allowing seamless evolution from

CDMA2000 1X through CDMA2000 1xEV-DO (Evolution - Data Only, offering

data speeds of up to 2.4 Mbps on a separate 1.25 MHz carrier) and CDMA2000


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1xEV-DV (Evolution Data/Voice, which integrates voice and data on the same

1.25 MHz carrier and offers data speeds of up to 4.8 Mbps).

5. HARDWARE

A2 ASIC Chip

The SPH-X2000 cell phone(BY SAMSUNG & GEO) uses the GEO Emblaze A2

video ASIC chip to deliver video over the wireless system. The A2 ASIC chip is

integrated into the cell phones to allow it to play multimedia (Figure ). The A2 ASIC

chip is based on the ARM platform as a high-performance, fully programmable core

processor, and includes on-chip memory. The interfaces also include the LCD

controller, Voice codec, Audio DAC and flash memory. This chip can deliver and

receive the MPEG4 video code over the second generation network, which are the

CDMA, the TDMA and the GSM. The SPH-X2000 cell phone is an amazing product

because many people think that video cell phones cannot function with the second

generation network. Fortunately, it is compatible with the existing CDMA systems at

a speed of 9.6 kbps, 64 kbps and CDMA2000 1X. The A2 video ASIC chip candeliver 15 frames per second with the second generation network. The cell phone is

also able to deliver 30 frames per second depending on the speed of the network. In

other words, the phone enables different viewing features. Some examples are

through video size, speed and image quality according to the different bandwidths

provided by different networks. These bandwidths vary between 2G, 2.5G and 3G.

The phone can deliver and receive larger video sizes; when the bandwidth of the

network is increased, there will be smoother images and better image quality.


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Wireless Multimedia Terminal Based on A2


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The A2 ASIC chip--Working:

The A2 ASIC chip works like this: it receives a compressed video and audio

from a baseband chip, and then decodes the video and audio. After, the baseband

chip sends the decoded video and audio to the LCD controller, it is then sent to the

voice codec / audio DAC. The external Flash memory is used for storing the A2

ASIC software. Other than that, the A2 ASIC includes all the memory it needs for

processing and depicting data. This eliminates the need for an external memory and

saves both power and space that are crucial in mobile applications.

The A2 ASIC chip is usually controlled by a baseband chip, which is the

host. A generic host bus and a programmable host protocol enable the A2 ASIC chip

to be used as a multi media co-processor for a wide variety of baseband devices.

Both the baseband chip and the A2 ASIC chip drive the voice codec. In order to save

external glue, the multiplex between these two is implemented in the A2 ASIC chip.

Thus, the A2 ASIC chip gets the voice output from the baseband and passes it to the

voice codec.

An on-chip power management unit generates internal frequencies out from

an external 27.00 MHz clock. There is a specific application running on the power

management unit which can be controlled by the host and programmable. When

running at full performance, 100 MHz, the A2 ASIC chip consumes ~700 mW. A

shutdown pin puts the A2 ASIC chip into a shut down mode which consumes less

than 1 mA. In the shut down mode, the only thing that is active is the passing

through of the voice data.


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The heart of the device is the ARM920 , an industry standard RISC. All the

media and network protocols are implemented by software to insure maximize

flexibility. We can see in figure 2 that a 160 KB SRAM is used to store all the data

that is needed for the video, audio and system protocols. The A2 ASIC chip includes

ARM system peripherals such as interrupt control unit (ICU), two timers, real time

clock (RTC) and a general purpose IO (GPIO). The glueless interface to the LCD

controller, Voice codec, flash memory and host completes the device.

Features of the A2 Chip

ASIC Characteristics

Package: 144 FlexBGA

0.25 CMOS

2.5 volts core

3 volts I/O

Active power: 700 mW

Shutdown mode current - less than 1 mA

Video Decoding

MPEG-4 Simple profile Level 1

Bit rate: Up to 144 kbps

Image size: Up to QCIF (176x144 pixels)

Frame rate: Up to 30 frames/second

Voice Decoding

G.723.1

File Format & Transport Protocol

MPEG-4


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ESF (Emblaze streaming format)

LCD Controller Port

YUV 4:2:2 color space

QCIF resolution

Voice Codec Interface

PCM style. Configurable

Host Inteface

8 bits generic (Intel style) bus


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A2 INTERNAL BLOCK DIAGRAM


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6. VIDEO CODE (MPEG4)

Consumer Electronics has always been driven by various standards.Thesestandards have driven the changes that have occurred in the product ranges in the

audio-visual format.MPEG is a data compression technology that reduces the size of

the original information many times before encoding it. MPEG has been

international standards since 1993.Because movies contain both images and sound,

MPEG can compress both audio and video. But video takes more bandwidth and also

contains more redundancy than audio.

Video Code:

The last concern of developing a video cell phone is the video code. The

video cell phone needs a high compression with a low bitrate code. Fortunately, this

is already available to use. The Moving Picture Experts Group (MPEG) is a working

group of ISO/IEC. They are in charge of the development of international standards

for compression, decompression, processing, and coded representation of moving

pictures, audio and their combination. MPEG-4 Systems is a subgroup under MPEG.The MPEG-4 group develops the tools to support the coded representation of the

combination of streamed elementary audiovisual information. The information has

many different forms: natural or synthetic, audio or visual, 2D and 3D objects within

the context of content-based access for digital storage media, digital audiovisual

communication and other applications.

.

MPEG 4


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This is the next generation MPEG code. It goes beyond compression

methods. Instead of treating data as continuous streams,MPEG-4 actually

deals with audio-video objects(AVO) that are manipulated and encoded

independently, allowing for increased interaction with the code data and

improved flexibility in editing. It supports the entire gamut of audio-video

modes and their respective transmission speeds.

MPEG 4 has been specifically designed to deal with high

compression ratios for distribution of video and audio without too much loss

of quality over low bandwidth networks. It offers a wide range of bit rates.It

provides the fastest encoding with the highest video quality.

MPEG-4 Systems Version 1 contains several different sets of tools to

reconstruct a synchronous interactive and streamed audiovisual scene. There

are five tools:

1. Systems Decoder Model (SDM),

2. Identification and association of scenes and streams (Object and

Elementary Streams Descriptors),

3. Scene description (Binary Format for Scenes),

4. Synchronization of streams (Sync. Layer),

5. Efficient multiplexing of streams (FlexMux),

6. Object Content Information (OCI) and,

7. Syntactic Description Language.

Systems Decoder Model (SDM)


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The systems decoder model includes two models: the timing model and

the buffer model. The model observes the behavior of an MPEG-4 terminal.

When reconstructing the audiovisual information that comprises the session, the

SDM will also allow a sender to predict how the receiver will behave in terms of

buffer management and synchronization.

Identification and Association of Scene and Streams (Object Descriptor)

The intention of the object descriptor framework is to recognize, illustrate

and combine elementary streams with the various components of an

audiovisual scene. An object descriptor is a collection of one or more

elementary stream descriptors. These descriptors provide configuration and

other information for the streams that relate to a single object (media object

or scene description). Elementary stream descriptors include information

about the source of the stream data. The information comes in the form of a

unique numeric identifier (the Elementary Stream ID) or a URL pointing to a

remote source for the stream.

Object Descriptors group several elementary streams into objects, and

describe their properties, such as encoding formats, configuration information

for the decoder, quality of service requirements, content information (author,

title, rating, etc.) and intellectual property identification. It can also describe

dependencies between streams for scalability, alternative representations, etc.

Scene Description (Binary Format for Scenes)


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The scene description addresses the organization of audiovisual objects in a

scene. It is done through the spatial and temporal positioning terms. This

information allows the composition and rendering of individual audiovisual

objects. This specification, however, does not mandate particular composition,

rendering algorithms or architectures since they are implementation-dependent.

Synchronization of Streams (Sync. Layer)

The elementary streams are the basic concept for any data source. Elementary

streams are conveyed as SL-packetized (Sync Layer-packetized) streams at the

stream multiplex interface. Furthermore, this packet representation provides

timing and synchronization information, and also, fragmentation and random

access information. The SL extracts this timing information to enable

synchronized decoding and, afterward, composition of the Elementary Stream

data.

It adds a header to each access unit of an elementary stream, which

includes time stamps, reference to a clock elementary stream, and identification

of key frames (RandomAccessPoint). This is similar to the task of RTP in IP

networks. However, SL does not contain a payload type (like RTP), and does not

contain the Elementary Stream ID (ES_ID). In addition, an SL packet does not

contain an indication of its length, so it must be framed by a lower-level protocol

such as FlexMux or RTP.

Multiplexing of Elementary Streams (FlexMux)

The TransMux layer is a generic abstraction of the transport protocol stacks of

existing delivery layers. These stacks may be used to transmit and store content

complying with the MPEG-4 Standard. The functionality of FlexMux is where


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the desired data transport protocol stacks (TransMux Layer)transport facility

does not fully address, a simple multiplexing tool (FlexMux) is defined that

provides low delay and low overhead.

This groups elementary streams according to common attributes, such as QOSrequirements. This is a very simple multiplexing protocol, but also very low

overhead.

OCI Data Stream

An object content information (OCI) stream carries descriptive information about

audiovisual objects. The stream is prearranged in a sequence of small,

synchronized entities called, events, which contain information descriptors. The

main content descriptors are: content classification descriptors, keyword

descriptors, rating descriptors, language descriptors, textual descriptors, and

descriptors about the creation of the content. These streams can be linked to other

media objects with the mechanisms provided by the object descriptor.

Syntactic Description Language

A syntactic description language is used to define the syntax of the various

bitstream components identified by the normative parts of the MPEG-4 Standard.

This language allows the specification of the mapping of the various parameters

in a binary format. It also shows how the binary format should be placed in a

serialized bitstream.


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MPEG Architecture


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Compression Layer: Includes elementary (raw) media streams (audio, video

etc.).

Transmux Layer: This is the actual transport protocol, such as RTP/UDP,

MPEG-2, etc. MPEG-4 does not define its own transport protocol, butassumes the application relies on an existing transport protocol.

The FlexMux Layer is optional, but the Synchronization Layer is always present.

BIFS - The Binary Interchange Format for Scenes (BIFS) describes how

MPEG-4 Objects are placed in "Scenes". This part of MPEG-4 Systems is

obviously not required for small-screen, single-media-object applications.

The AVO data are basically conveyed in one or more elementary

streams.These streams contain elements such as maximum bit rate,bit error

rate ,quality as well as other parameters,includeing stream type information

to determinr the required decoder sources and the precision for encoding

timing information.The total data encoded in each of these streams finally

makes up the entire scene.

Depending on the nature of the scene,the details in each frame of the

scene alter to an extent. But as the particular object moves through its

surrounding, many times the background and environment reamin same

.Sometimes the angle might change ,but this is not noticeable as the scene

changes too fast for the eye to catch it.

MPEG 2 v/s MPEG 4


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It is seen that the total bandwidth required by MPEG-2 at an average is a

massive 6500Kbits/sec at a resolution of 720*576 whereas at the same

resolution MPEG-4 uses only 880 Kbits/sec.This goes out to show that MPEG-4

provides relatively high quality audio-video data transmission over various

broadcast mediums.

MPEG 4 definitely offers better compression algorithms tha MPEG 1 and

MPEG 2, but all this comes with a huge performance demand as encoding of an

MPEG 4 sequence requires some pretty high-end computing power.

CONCLUSION


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The telecommunications world is changing as the trends of media convergence,

industry consolidation, Internet and IP technologies and mobile communications

collide into one. Significant change will be bought about by this rapid evolution in

technology. People will look at their mobile phone as much as they hold it to their

ear. The mobile phone will be used as an integral part of the majority of peoples

lives- it will not be an added accessory but a core part of how they conduct their

daily lives. The mobile phone will become akin to a remote control or magic wand

that lets people do what they want and when they want so much so that from saying

You have got mail ,we might actually say You have got Video!.

The existing phone allows users to view rich media content directly on their

mobile phones by simply pressing the video function key and browsing through the

list of available content, in a similar fashion to TV channels.

However, it's pretty unlikely in the next couple years that people will watch

full-length movies or even music videos as the cost to end-users is prohibitive.A

video cellphone handset costs anywhere between $600 to $700.But , as bandwidth

increases, the user can enjoy larger video size with a smoother image and better

image quality.

BIBLIOGRAPHY

Websites

www.mobilevideoworld.com

www.wired.com
http://www.mobilevideoworld.com/http://www.wired.com/http://www.mobilevideoworld.com/http://www.wired.com/


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www.newscientist.com

www.cnet.com

www.wirelessnewsfactor.com

www.3g.co.uk

www.infoworld.com

www.samsung.com

www.wireless.iop.org

www.zapex.co.il

www.telecomitalialab.com

www.eetimes.com

www.nttdocomo.com

www.emblaze.com

www.cdg.org

http://woody.imag.fr/MPEG4

www.efunda.com

Other

Tanenbaum,Andrew S.,Computer Networks,Prentice-Hall India.

Digit Magazine
http://www.newscientist.com/http://www.cnet.com/http://www.wirelessnewsfactor.com/http://www.3g.co.uk/http://www.infoworld.com/http://www.samsung.com/http://www.wireless.iop.org/http://www.zapex.co.il/http://www.telecomitalialab.com/http://www.eetimes.com/http://www.nttdocomo.com/http://www.emblaze.com/http://www.cdg.org/http://woody.imag.fr/MPEG4http://www.efunda.com/http://www.newscientist.com/http://www.cnet.com/http://www.wirelessnewsfactor.com/http://www.3g.co.uk/http://www.infoworld.com/http://www.samsung.com/http://www.wireless.iop.org/http://www.zapex.co.il/http://www.telecomitalialab.com/http://www.eetimes.com/http://www.nttdocomo.com/http://www.emblaze.com/http://www.cdg.org/http://woody.imag.fr/MPEG4http://www.efunda.com/


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Schiller ,Jochen H. ,Mobile Communications,Pearson EducationLimited,India.

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