final multimedia

What Is Multimedia?

CECS 5110

What Is Multimedia?

Multimedia is a computer-based interactive communications process that incorporates text, graphics, sound, animation, and video

InteractiveKey feature of multimediaUser determines what content is delivered,

when it is delivered and how

Non-linear

Computer-based Multimedia

2 or more media Computer multimedia

Multi-sensory experience – real world Multi-sensory memory imprints Different learning styles benefit

Hypertext - links

Hypermedia - hypermedia ware

Multimedia Advantages

Engrossing – deep involvement Multi-sensory Creates knowledge connections Individualized Teacher and student creation

Multimedia Disadvantages

“Lost in cyberspace” Lack of structure Non-interactive – if one-way, no feedback Text intensive content Complex to create Time consuming Cognitive overload Linear content

Multimedia GrowthUser Standpoint (cont.)

Action Active processes: simulations, acting out a play,

testing knowledge and feedback

Examples500 Nations, Grandma and Me , Magic School Bus

Major Categories of Multimedia Titles

Entertainment

Education

Corporate communications

Reference


Entertainment Games: action and graphics Action + storytelling Physical coordination + mental outwitting

Education Accommodates different learning styles:

association vs. experimentation; auditory vs. visual

Provides feedback, levels of difficulty, evaluates skills, nonlinear presentations


Corporate communications (marketing and training)

Attract attention to a messageProduct catalogs, published magazines, touch-

screen kiosks, online shopping, …Stockholder's meeting, sales rep pitch,

conference speaker, employee orientation and training, …


ReferenceCD: encyclopedias, census data, directories,

dictionaries

Delivering Multimedia

Compact disc Inexpensive, easy mass produce and distribute

Kiosk Computer system to access info, perform

transactions or play games Convenience, reduces personnel costs, but

expensive maintenance Online

Web pages, product advertisement, demos, …

Communications SystemsThe topics within this unit are:

Characteristics of communication systems. Examples of communication systems. Transmitting and receiving in communication

systems. Other information processes in communication

systems. Issues related to communication systems.

More Information

must be a Sender and ReceiverA protocol is a set of rules which governs the

transfer of data between computers. Protocols allow communication between computers and networks.

Handshaking is used to establish which protocols to use. Handshaking controls the flow of data between computers

protocols will determine the speed of transmission, error checking method, size of bytes, and whether synchronous or asynchronous

Examples of protocols are: token ring, CSMA/CD, X.25, TCP/IP

Characteristics of Communication Systems

5 Basic Components

•Bandwidth:The amount of data which can be transmitted on a medium over a fixed amount of time (second). It is measured on Bits per Second or Baud

•Bits per Second (bps): A measure of transmission speed. The number of bits (0 0r 1) which can be transmitted in a second (more)

•Baud Rate: Is a measure of how fast a change of state occurs (i.e. a change from 0 to 1) (more)

Transmission Media Speed

This file has now been broken into four packets

PACKET

Packets

Transmissions are broken up into smaller units or data transmissions called packets

PACKET PACKET PACKET

ExampleA data file is divided into packets.It does not matter what the transmission is. It could be Word document, a PowerPoint or an MP3. Imagine this Green box is a file for transfer

Examples of Communication Systems

- E-mail- Voice Mail - Fax- Smart Phone - Instant Messaging- Telecommuting - Video-conferencing - Groupware - Telephony- E-Commerce - The Internet- Bulletin board system - The Web- Global positioning system

- simplex: One direction only

Transmission Direction

Graham Betts

Half Duplex Transmission

half duplex: Both directions but only one direction at a time

Graham Betts

Full Duplex Transmission

full duplex: send and receive both directions at once

Components of Multimedia

• Multimedia involves multiple modalities of text, audio, images, drawings, animation, and video.

Examples of how these modalities are put to use:1. Video teleconferencing.2. Distributed lectures for higher education.3. Tele-medicine.4. Co-operative work environments.5. Searching in (very) large video and image databases for

target visual objects.6. “Augmented” reality: placing real-appearing computer

graphics and video objects into scenes.

7. Including audio cues for where video-conference participants are located.

8. Building searchable features into new video, and enabling very high- to very low-bit-rate use of new, scalable multimedia products.

9. Making multimedia components editable.

10. Building “inverse-Hollywood” applications that can recreate the process by which a video was made.

11. Using voice-recognition to build an interactive environment, say a kitchen-wall web browser.

Multimedia Research Topics and Projects

• To the computer science researcher, multimedia consists of a wide variety of topics:

1. Multimedia processing and coding: multimedia content analysis, content-based multimedia retrieval, multimedia security, audio/image/video processing, compression, etc.

2. Multimedia system support and networking: network protocols, Internet, operating systems, servers and clients, quality of service (QoS), and databases.

3. Multimedia tools, end-systems and applications: hypermedia systems, userinterfaces, authoring systems.

4. Multi-modal interaction and integration: “ubiquity” — web-everywhere devices, multimedia education including Computer Supported Collaborative Learning, and design and applications of virtual environments.

Current Multimedia Projects

• Many exciting research projects are currently underway. Here are a few of them:

1. Camera-based object tracking technology: tracking of the control objects provides user control of the process.

2. 3D motion capture: used for multiple actor capture so that multiple real actors in a virtual studio can be used to automatically produce realistic animated models with natural movement.

3. Multiple views: allowing photo-realistic (video-quality) synthesis of virtual actors from several cameras or from a single camera under differing lighting.

4. 3D capture technology: allow synthesis of highly realistic facial animation from speech.

5. Specific multimedia applications: aimed at handicapped persons with low vision capability and the elderly — a rich field of endeavor.

6. Digital fashion: aims to develop smart clothing that can communicate with other such enhanced clothing using wireless communication, so as to artificially enhance human interaction in a social setting.

7. Electronic Housecall system: an initiative for providing interactive health monitoring services to patients in their homes

8. Augmented Interaction applications: used to develop interfaces between real and virtual humans for tasks such as augmented storytelling.

1.2 Multimedia and Hypermedia

• History of Multimedia:

1. Newspaper: perhaps the first mass communication medium, uses text, graphics, and images.

2. Motion pictures: conceived of in 1830’s in order to observe motion too rapid for perception by the human eye.

3. Wireless radio transmission: Guglielmo Marconi, at Pontecchio, Italy, in 1895.

4. Television: the new medium for the 20th century, established video as a commonly available medium and has since changed the world of mass communications.

5. The connection between computers and ideas about multimedia covers what is actually only a short period:

1945 – Vannevar Bush wrote a landmark article describing what amounts to a hypermedia system called Memex.

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1960 – Ted Nelson coined the term hypertext.

1967 – Nicholas Negroponte formed the Architecture Machine Group.

1968 – Douglas Engelbart demonstrated the On-Line System (NLS), another very early hypertext program.

1969 – Nelson and van Dam at Brown University created an early hypertext editor called FRESS.

1976 – The MIT Architecture Machine Group proposed a project entitled Multiple Media — resulted in the Aspen Movie Map, the first hypermedia videodisk, in 1978.

1985 – Negroponte and Wiesner co-founded the MIT Media Lab.

1989 – Tim Berners-Lee proposed the World Wide Web

1990 – Kristina Hooper Woolsey headed the Apple Multimedia Lab.

1991 – MPEG-1 was approved as an international standard for digital

video — led to the newer standards, MPEG-2, MPEG-4, and further MPEGs in the 1990s.

1991 – The introduction of PDAs in 1991 began a new period in the use of computers in multimedia.

1992 – JPEG was accepted as the international standard for digital image compression — led to the new JPEG2000 standard.

1992 – The first MBone audio multicast on the Net was made.

1993 – The University of Illinois National Center for Supercomputing

Applications produced NCSA Mosaic—the first full-fledged browser.

1994 – Jim Clark and Marc Andreessen created the Netscape program.

1995 – The JAVA language was created for platform-independent application development.

1996 – DVD video was introduced; high quality full-length movies were distributed on a single disk.

1998 – XML 1.0 was announced as a W3C Recommendation. 1998 – Hand-held MP3 devices first made inroads into

consumerist tastes in the fall of 1998, with the introduction of devices holding 32MB of flash memory.

2000 – WWW size was estimated at over 1 billion pages.

Hypermedia and Multimedia

• A hypertext system: meant to be read nonlinearly, by following links that point to other parts of the document, or to other documents (Fig. 1.1)

• HyperMedia: not constrained to be text-based, can include other media, e.g., graphics, images, and especially the continuous media – sound and video.

- The World Wide Web (WWW) — the best example of ahypermedia application.

• Multimedia means that computer information can be represented through audio, graphics, images, video, and animation in addition to traditional media.

Fig 1.1: Hypertext is nonlinear

• Examples of typical present multimedia applications include:

– Digital video editing and production systems. – Electronic newspapers/magazines. – World Wide Web. – On-line reference works: e.g. encyclopedia, games, etc. – Home shopping. – Interactive TV. – Multimedia courseware. – Video conferencing. – Video-on-demand. – Interactive movies.

1.4 Overview of Multimedia Software Tools

• The categories of software tools briefly examined here are:

1. Music Sequencing and Notation

2. Digital Audio

3. Graphics and Image Editing

4. Video Editing

5. Animation

6. Multimedia Authoring

Music Sequencing and Notation

• Cakewalk: now called Pro Audio.

– The term sequencer comes from older devices that stored sequences of notes (“events”, in MIDI).– It is also possible to insert WAV files and Windows MCI commands (for animation and video) into music tracks (MCI is a ubiquitous component of the Windows API.)

• Cubase: another sequencing/editing program, with capabilities similar to those of Cakewalk. It includes some digital audio editing tools.

• Macromedia Soundedit: mature program for creating audio for multimedia projects and the web that integrates well with other Macromedia products such as Flash and Director.

Digital Audio

• Digital Audio tools deal with accessing and editing the actual sampled sounds that make up audio:

– Cool Edit: a very powerful and popular digital audio toolkit; emulates a professional audio studio — multitrack productions and sound file editing including digital signal processing effects.

– Sound Forge: a sophisticated PC-based program for editing audio WAV files.

– Pro Tools: a high-end integrated audio production and editing environment — MIDI creation and manipulation; powerful audio mixing, recording, and editing software.

Graphics and Image Editing

• Adobe Illustrator: a powerful publishing tool from Adobe. Uses vector graphics; graphics can be exported to Web.

• Adobe Photoshop: the standard in a graphics, image processing and manipulation tool.

– Allows layers of images, graphics, and text that can be separately manipulated for maximum flexibility.– Filter factory permits creation of sophisticated lighting-effects filters.

• Macromedia Fireworks: software for making graphics specifically for the web.

• Macromedia Freehand: a text and web graphics editing tool that supports many bitmap formats such as GIF, PNG, and JPEG.

Video Editing

• Adobe Premiere: an intuitive, simple video editing tool for nonlinear editing, i.e., putting video clips into any order:

– Video and audio are arranged in “tracks”.– Provides a large number of video and audio tracks, superimpositions and virtual clips.– A large library of built-in transitions, filters and motions for

clips effective multimedia productions with little effort.

• Adobe After Effects: a powerful video editing tool that enables users to add and change existing movies. Can add many effects: lighting, shadows, motion blurring; layers.

• Final Cut Pro: a video editing tool by Apple; Macintosh only.

Animation

• Multimedia APIs:

– Java3D: API used by Java to construct and render 3D graphics, similar to the way in which the Java Media Framework is used for handling media files.

1. Provides a basic set of object primitives (cube, splines, etc.) for building scenes.

2. It is an abstraction layer built on top of OpenGL or DirectX (the user can select which).

– DirectX: Windows API that supports video, images, audio and 3-D animation

– OpenGL: the highly portable, most popular 3-D API.

• Rendering Tools:

– 3D Studio Max: rendering tool that includes a number of very high-end professional tools for character animation,

game development, and visual effects production.– Softimage XSI: a powerful modeling, animation, and rendering

package used for animation and special effects in films and games.

– Maya: competing product to Softimage; as well, it is a complete modeling package.

– RenderMan: rendering package created by Pixar.

• GIF Animation Packages: a simpler approach to animation, allows very quick development of effective small animations for the web.

Multimedia Authoring

• Macromedia Flash: allows users to create interactive movies by using the score metaphor, i.e., a timeline arranged in parallel event sequences.

• Macromedia Director: uses a movie metaphor to create interactive presentations — very powerful and includes a built-in scripting language, Lingo, that allows creation of complex interactive movies.

• Authorware: a mature, well-supported authoring product based on the Iconic/Flow-control metaphor.

• Quest: similar to Authorware in many ways, uses a type of flowcharting metaphor. However, the flowchart nodes can encapsulate information in a more abstract way (called frames) than simply subroutine levels.

Application Areas

Residential Services video-on-demand video phone/conferencing systems multimedia home shopping (MM catalogs, product demos and

presentation) self-paced education

Business Services Corporate training Desktop MM conferencing, MM e-mail

Application Areas

Education Distance education - MM repository of class videos Access to digital MM libraries over high speed networks

Science and Technology computational visualization and prototyping astronomy, environmental science

Medicine Diagnosis and treatment - e.g. MM databases that provide support for

queries on scanned images, X-rays, assessments, response etc.

Classification of Media

Perception Medium How do humans perceive information in a computer?

Through seeing - text, images, video Through hearing - music, noise, speech

Representation Medium How is the computer information encoded?

Using formats for representing and information ASCII(text), JPEG(image), MPEG(video)

Presentation Medium Through which medium is information delivered by the computer or

introduced into the computer? Via I/O tools and devices paper, screen, speakers (output media) keyboard, mouse, camera, microphone (input media)

Classification of Media (cont.)

Storage Medium Where will the information be stored? Storage media - floppy disk, hard disk, tape, CD-ROM etc.

Transmission Medium Over what medium will the information be transmitted? Using information carriers that enable continuous data transmission -

networks wire, coaxial cable, fiber optics

Information Exchange Medium Which information carrier will be used for information exchange

between different places? Direct transmission using computer networks Combined use of storage and transmission media (e.g. electronic mail).

What Peripheral Devices Suit Your Needs?

Input DevicesInput Devices Output DevicesOutput Devices Storage DevicesStorage Devices

5.1 Input Devices• Input device captures information and translates it into a form that can be processed and used by other parts of your computer. KeyboardsPointing devicesGame controllersScannersStylusesMicrophonesDigital camerasWeb cams

Input Devices The keyboard is the most common input

device. Types of keyboards include:• Wireless

• Multimedia and one-touch access

• Portable keyboards for PDAs

Types of Input Devices

Pointing Devices Pointing devices are mainly used to choose and

enter commands

Pointing devices tend to have PS/2 connectors or USB connectors

• PS/2 connector fits into a PS/2 port, which a small round socket with small holes that fit the pins on the connector

• USB connectors fit into USB ports, and these are small rectangular openings on the back or front of your computer, or even on your keyboard or monitor

Pointing Devices Various pointing devices are available

Types of pointing devices:

• MouseMechanical mouse

Optical mouse

Wireless mouse

• Trackball

• Touchpad

• Pointing stick

Game Controller Game controllers are used mainly to play games

Types of gaming devices• Gamepads

• Joysticks

• Gaming wheels

• Force feed

Specialized Input Devices

Other types of input devices include:• Scanners

• Styluses

• Microphones

• Digital cameras

• Web cams

Scanner•Scanner is a light sensitive device that helps you copy or capture images, photos, and artwork that exist on paper. Types of scanners include:Flatbed

Styluses• Stylus is an input device consisting of a thin

stick that uses pressure to enter information or to click and point

• Styluses are used with:PDAs Tablet PCsGraphics tablets

Microphones• Microphones are used to

input audio • Three main types of

microphones are:Desktop microphonesHeadsetsDirectional microphones

• Speech recognition is increasingly being included in application software

Digital Cameras Digital cameras are used to:

• Download images to a computer• Post pictures to the Web• Produce videos

Resolution is measured in megapixels Higher the resolution, better the

image quality, but the more expensive the camera

Web Cams• Web cam is a video camera

that can be used to take images for uploading to the Web

5.2 Output Devices

Output devices take information within your computer and present it to you in a form that you can understand

Main output devices: Monitors Printers Speakers

Flat Panel Display DevicesDevices with flat-panel displays

• Tablet PCs

• PDAs

• Cellular phones

• Desktop computers

MonitorsCRTsFlat-panel displays

Gas plasma LCD (liquid crystal display)

Passive matrix Active matrix

Called TFT (thin film transistor) Separate transistor for every pixel

Screen Talk Screen size measured as a diagonal line across the screen

– from corner to opposite corner Resolution the number of pixels displayed on the screen

(the higher the resolution, the closer together the dots) Pixels (or picture element) dots that make up the image

on your screen Dot pitch is the distance between the centers of a pair of

like-colored pixels Refresh rate the speed with which a monitor redraws the

image of the screen, and is measured in hertz

Printers Inkjet – most popular

Makes images by forcing droplets through nozzles

Top speed is 20 pages per minute

Laser Forms images using an electrostatic

process Prints between 3 and 30 pages per

minute

Printers - ContResolution of a printer is the

number of dots per inch (dpi) it produces.

Higher the resolution, better the image, and usually the more costly the printer

Printers - Cont.

Multifunction printer:

• Scan, copy, fax, and print

• Can be either inkjet or laser

• Cost less than buying individual units

• Take up less desk space

Speakers A speaker is a device that

produces computer output as sound

Speakers are common devices in computer systems Examples include:• Built-in speaker

• Two-device set speakers

• Surround sound speakers

5.3 Storage Devices Storage device stores information to be

recalled and used at a later time Storage device consists of:

Storage mediumStorage device

Three major technology types for information storage:

MagneticOptical or laserFlash memory

Magnetic Storage Devices: Internal Magnetic Hard Disk

Magnetic storage devices can be either internal or external• Internal magnetic hard disks are

fixed inside the system unit• External magnetic hard disks are

portable

Magnetic Storage Devices: Internal Magnetic Hard Disk

Internal hard disk is a magnetic storage device with

• One or more thin platters that store information sealed inside the disk drive.

• Read/write heads access the information on surface

• Heads read information while copying it from disk to RAM

• Heads write information when copying it from RAM to disk

Magnetic Storage Devices: External Magnetic Hard Disk

External hard disks are magnetic storage media which are portable storage units that you can connect to your computer as necessary

• Great for backup storage devices• Ability to transport your hard disk

from one computer to another

Hard Drives

Long term storage system and application software

Operating system and application software are copied from the hard disk to memory

Capacity measured in gigabytes

Floppy Disks and Zip DisksRemovable magnetic storage media

come in two basic types: Traditional floppy disks Zip disks

These storage media are useful for: Storing files for backup or security

purposes Transferring files from one computer to

another

Removable Magnetic Storage: Floppy Disk

Floppy Mylar disk Housed inside a hard plastic

casing Thin, flexible plastic disk

3.5 inch floppy disks also called floppies, diskettes, floppy

disks Holds about 1.44 megabytes of

information High-capacity disks

Zip® disk

p. 5.144 Fig. 5.15

Removable Magnetic Storage: Zip Disk

High capacity plastic platter disk Called removable hard disks Provide a higher storage capacity than Mylar

disks Example - Zip® disk with capacity of 100MB, 250MB, and

750MB

Optical Storage

CDs DVDs Both are optical storage

and have three formats: Read-only Write-once Read-and-write

Optical Storage Media Read-Only

CD-ROM DVD-ROM

One-Time Writable CD-R DVD-R DVD+R

Fully Read-and-Write CD-RW DVD-RW or

DVD+RW or

DVD-RAM

Flash Memory Cards Flash memory cards have high-

capacity storage laminated inside a small piece of plastic

Flash flash memory cards do not need a drive with moving parts to operate

Flash Memory Talk CompactFlash (CF) xD-Picture Card (xD) SmartMedia (SM) Card SecureDigital (SD) card and

MultiMediaCards (MMC) Memory Stick Media

Flash Memory Card Readers Some devices have flash memory slots into

which you slide your flash memory card Other devices can use an external flash

memory card reader in order to transfer information

A flash memory drive is a flash memory storage medium for a computer that is small enough to fit in your pocket and usually plugs directly into a USB port

Overview: Computer Imaging

Definition of computer imaging: Acquisition and processing of visual information by

computer.

Why is it important? Human primary sense is visual sense. Information can be conveyed well through images

(one picture worth a thousand words). Computer is required because the amount of data to

be processed is huge.


Computer imaging can be divided into two main categories: Computer Vision: applications of the output are for

use by a computer. Image Processing: applications of the output are for

use by human.

These two categories are not totally separate and distinct.


They overlap each other in certain areas.

Computer Vision

Image Processing

COMPUTER IMAGING

Computer Vision

Does not involve human in the visual loop.

One of the major topic within this field is image analysis (Chapter 2).

Image analysis involves the examination of image data to facilitate in solving a vision problem.

Computer Vision

Image analysis process involves two other topics: Feature extraction: acquiring higher level image

info (shape and color) Pattern classification: using higher level image

information to identify objects within image.

Computer Vision

Most computer vision applications involve tasks that: Are tedious for people to perform. Require work in a hostile environment. Require a high processing rate. Require access and use of a large database of

information.

Computer Vision

Examples of applications of computer vision: Quality control (inspect circuit board). Hand-written character recognition. Biometrics verification (fingerprint, retina, DNA,

signature, etc). Satellite image processing. Skin tumor diagnosis. And many, many others.

Image Processing

Processed images are to be used by human. Therefore, it requires some understanding on how

the human visual system operates.

Among the major topics are: Image restoration (Chapter 3). Image enhancement (Chapter 4). Image compression (Chapter 5).

Image Processing

Image restoration: The process of taking an image with some know,

or estimated degradation, and restoring it to its original appearance.

Done by performing the reverse of the degradation process to the image.

Examples: correcting distortion in the optical system of a telescope.

Image Processing

An Example of Image Restoration

Image Processing

Image enhancement: Improve an image visually by taking an

advantage of human visual system’s response. Example: improve contrast, image sharpening,

and image smoothing.

Image Processing

An Example of Image Enhancement

Image Processing

Image compression: Remove the amount of data required to represent

an image by: Removing unnecessary data that are visually unnecessary. Taking advantage of the redundancy that is inherent in most

images.

Example: JPEG, MPEG, etc.

Digital Image File Formats

There are many different types of image file formats. This is because: There are many different types of images and

applications with varying requirements. Lack of coordination within imaging industry.

Images can be converted from one format to another using image conversion software.


Types of image data are divided into two categories: Bitmap (raster) images: where we have pixel data and

the corresponding brightness values stored in some file format.

Vector images: methods of representing lines, curves and shapes by storing only the key points. The process of turning the key points into an image is called rendering.


Most of the file formats to be discussed fall under the category of bitmap images.

Some of the formats are compressed. The I(r, c) values are not available until the file is

decompressed.

Bitmap image files must contain both header information and the raw pixel data.


The header contain information regarding: The number of rows (height) The number of columns (width) The number of bands The number of bits per pixel The file type Type of compression used (if applicable)


BIN format: Only contain the raw data I(r, c) and no header. Users must know the necessary parameters

beforehand.

PPM format: Contain raw image data with a simple header. PBM (binary), PGM (gray-scale), PPM (color) and

PNM (handles any of the other types).


GIF (Graphics Interchange Format): Commonly used in WWW. Limited to a maximum of 8 bits/pixel (256

colors). The bits are used as an input to a lookup table. Allow for a type of compression called LZW. Image header is 13 bytes long.


TIFF (Tagged Image File Format): Allows a maximum of 24 bits/pixel. Support several types of compression: RLE,

LZW, and JPEG. Header is of variable size and is arranged in a

hierarchical manner. Designed to allow user to customize it for

specific applications.


JFIF (JPEG File Interchange Format): Allows images compressed with JPEG algorithm

to be used in many different computer platforms. Contains a Start of Image (SOI) and an

application (APPO) marker that serves as a file header.

Being used extensively in WWW.


Sun Raster file format: Defined to allow for any number of bits per

pixel. Supports RLE compression and color lookup

tables. Contains 32-byte header, followed by the image

data.


SGI file format: Handles up to 16 million colors. Supports RLE compression. Contains 512-byte header, followed the image

data. Majority of the bytes in header are not used,

presumably for future extension.


EPS (Encapsulated PostScript): Not a bitmap image. The file contains text. It is a language that supports more than just

images. Commonly used in desktop publishing. Directly supported by many printers (in the

hardware itself). Commonly used for data interchange across

hardware and software platforms. The files are very big.

AUDIO STREAMING OVERVIEW

Audio File Features Audio Streaming Concept Audio Streaming Advantages Audio Streaming Applications Audio Streaming Format Audio Streaming Products

Audio File Features

Audio file is a record of captured sound that can be played back e.g. .WAV File

Audio files are compressed for storage or faster transmission

Requires high bandwidth to transfer across the network

LAN, Intranet, Internet

Audio Streaming Concept

.WAV Live Broadcast

.ASF

Real Producer.RM

Windows Media Encoder Real Producer 7.0

kPC

Audio FormatkPC

Windows MediaStreaming Software

Audio Streaming Concept

Analog-to-Digital modulation Streaming audio technologies relies on:

Sound sequences Compression schemes

Compression schemes (encoding) decreases the audio’s bandwidth requirements: Lowering the audio’s sampling rate Filtering high frequencies Performing other waveform

Audio Streaming Advantages

Real time audio content. Low bandwidth media used. No waiting for downloading audio file. Internet users can enjoy a live online program.

Audio Streaming Applications

Long-distance or automated training Seminars Concerts Speeches Music samples Online corporate messages Hear the news / Radio

Audio Formats

Microsoft Windows Media Formats .avi, .asf, .asx, .rmi, .wav

Moving Pictures Experts Group (MPEG) .mp3

Musical Instrument Digital Interface (MIDI) .mid, .rmi

Apple Quick Time, Macintosh AIFF Resource .qt, .aif, .aifc, .aiff, .mov

UNIX Formats .au, .snd

Audio Streaming Products

Window Media Technologies (Microsoft) RealSystem G2 (RealNetworks) Shockwave Streaming Audio (Macromedia) IBM Bamba (IBM) Streamworks (Xing Technology) Media Player (Netscape)

Video Streaming

Video Streaming Objective Streaming Advantages Video Streaming Architecture Compression and Decompression-codec MPEG 1-4 Introduction Major Products and Features Comparison

Video Streaming Objective

The object is to overcome the negative effects of physical distance and network technology limitation.

Streaming Advantages

Reduce setup time Reduction in client storage requirement Video can be viewed in real time Transmission signals over low bandwidth facilities

Video Streaming Architecture

Content Creation/Capture Content Management Content Formatting (Compression) Delivery Distribution Presentation (Viewing) View Control

Video Capture

Converting analog to video signals A special video capture card to convert the

analog signals to digital form and compresses the data.

Also digital video devices that can capture images and transfer to a computer

Video Input Formats

AVI ActiveMovie Cinepak Indeo motion-JPEG

MPEG QuickTime RealVideo Video for Windows XGA

Video FormatsAVI & ASF

Developed by Microsoft AVI (Audio Video Interleaved)

- limited to 320x240 resolution

- 30 frames per second ASF (Advanced Streaming Format)

- Has been submitted to ISO for standardization

- Expected to replace AVI format

Codec(Compressor/Decompressor)

Coding techniques to compress video data The newest codec change their sampling rate as

they run Choice of codec is the biggest factor to determine

the bandwidth needed to connect the server and receive content

Many of the codecs follow international standards

Content Compression

MPEG (A working group of ISO)- The most common standard for video

compression and file formats- Generally produce better quality video than other

formats- High compression rate- MPEG1, MPEG2 and MPEG4

MPEG-1

MPEG-1 was designed for coding progressive video at a transmission rate of about 1.5 million bits per second.

It was designed specifically for Video-CD and CD-i media.

MPEG-1 audio layer-3 (MP3) has also evolved from early MPEG work.

MPEG-2

MPEG-2 was designed for coding interlaced images at transmission rates above 4 million bits per second.

MPEG-2 is used for digital TV broadcast and

DVD.

An MPEG-2 player can handle MPEG-1 data as well.

MPEG-3

A proposed MPEG-3 standard, intended for High Definition TV (HDTV), was merged with the MPEG-2 standard when it became apparent that the MPEG-2 standard met the HDTV requirements.

MPEG-4

An MPEG-4 standard is in the final stages of development and release.

It is a much more ambitious standard and addresses speech and video synthesis, fractal geometry, computer visualization, and an artificial intelligence (AI) approach to reconstructing images.

final multimedia

Technology

multimedia advantages

multimedia disadvantages

computerbased multimedia

communications systems

computers protocols

feedback examples

census data

transfer of data