4 multimedia basics

1About Multimedia

Introduction to Multimedia

What does multimedia mean to you?

Multimedia is any presentation that combines several media such as text, animation, graphics, sound, video and streaming content.

Multimedia is the convergence of digital media. This means media producers must learn how to use multimedia to create content for TV, radio, video, and the Web.

2Types of Multimedia


Still Media

Any media or image that can be viewed within one single frame or a single image that does not change.

Examples: Photos or graphic images, logos, etc.



Dynamic Media

Examples: Animation, video, audio, etc.



Interactive Media

Examples: Animation, Web sites, CD/DVD authoring, software programming, etc.



Animation



Digital Video



Digital Audio



Streaming Media

So what is streaming anyway?

Streaming software like RealServer or QuickTime takes your video/audio file, segments it, and sends the pieces to a buffer on your hard drive. Then, the buffer renders the packets together to play like a continuous file, resulting in a smooth, high-quality track with a painless download time.

9Types of Software


Software

Text and Graphics: MS Word, Macromedia Freehand, Adobe Illustrator, Adobe Photoshop (bitmap), Macromedia Flash (vector-based)

Animation: Macromedia Flash and Director

Digital Video: iMovie2, Adobe Premiere, Final Cut Pro

10Types of Software


Software

Digital Audio: Pro Tools, Sound Forge, iTunes

Streaming: QuickTime, RealServer

Third-Party and Others: Adobe AfterEffects (add filters & effects to video), Cleaner 5 (encoding/compressing video, audio, etc.), Real Media, Sorenson Pro

11QuickTime


What is QuickTime?

It’s a file that tells the computer what kind of media to present and when to present it. The software is a gateway for distributing media including images, music, MP3 and more.

QuickTime lets you experience more than 200 kinds of digital media with a Mac or PC.

12Hardware and Equipment


Hardware and Equipment• Windows PC/Mac G4

• 300-512 Mb RAM

• 30-40 GB Hard Drive

• CD ROM, DVD RAM (CD-R, DVD-R)

• Two 17” Monitors

• FireWire or ATA Drives (30+ GB)

• Removable Media

13Hardware and Equipment


Hardware and Equipment• 3CCD Digital Video Camcorder (Sony, Canon)

• Digital Still Camera - 3-5 mega pixels* (Nikon, Sony)

• Converter or Deck (from DV to SVHS)

• Scanner (Hewlett Packard, Epson)

• Printer (optional)

* high-end

14End of Presentation


More Information• For software, visit www.macromedia.com (free 30-day trials of Flash, Dreamweaver and more!)

Other Links:

• www.cnet.com (latest prices, tutorials, and more)

• www.techsoup.org (CompuMentor’s site)

• Presentation by: Nettrice R. Gaskins, current Director of the BNN Multimedia Center & President of DigitalArt Communities, Inc.

Email: [email protected]

http://www.macromedia.com/

http://www.cnet.com/

http://www.techsoup.org/

15

Multimedia in the past…

For VIDEO: VCRs, Laserdiscs, videodiscs

For SOUND: cassette player or stereo system

For GRAPHICS: Film Slides or OHPs

For TEXT: as OHPs (overhead projectors)

16

Definition of Multimedia

Interactive multimedia means that all of

these elements are put together is such a way

that the user can control all or some aspects of

your software.

Multimedia is a collection of various elements called media that when combined form a single unit.

These media elements include video, sound, graphics, animation, and text.

The multimedia designer’s job is to

put together a product that is both

easy to use and interesting.

17

Convergence of industries & technologies

Multimedia is the convergence of different technologies. Technologies of sound, video, graphic design, publishing and animation combine in an interactive way in: Web applications (publishing, streaming

audio, hypertext, graphic design) Movies (digital video, animation) CD ROM development (audio, PC, DVD)

18

Applications of Multimedia Games Industry - PC, Video console, etc. Entertainment – Television, movies Education – Educational software, interactive

programs Training and Development

19

Multimedia PC Specification

750-MHz processor 64 MB RAM DVD drive recommended for Consumer & Office

systems; required for Entertainment PCs. CD ROM Rewritable (for creation of multimedia) 56-Kbps V.90 modem (Consumer and Entertainment) 17” monitor, 3D graphics accelerator card Speakers with sound card LOTS of hard drive space

20

Creating Multimedia - HardwareIn order to create a multimedia application, you will access to:

Microphone and speakers Scanner (capture images) video capture card (capture video) VCR (play video to be captured) Digital camera / still camera (capture images) Connection to the internet (capture images/text,

research)

21

Creating Multimedia - Software

In order to create multimedia application, you will need:

Macromedia Director Image editing software – Fireworks,

Photoshop, Paint Shop Pro, etc. Sound editing software – Cooledit, etc. Video editing software – Adobe Premier,

Videowave, etc.

Try www.download.com for trialware or shareware of sound, image or video

editing software.

http://www.download.com/

22

Creating Multimedia - Skills

In order to create multimedia application, be:

Organised. Creating a multimedia project is time-consuming. You must be organised and set time-goals for yourself.

Creative. Spend time analysing other software and websites. Search for graphic design techniques, etc.

23

Standards

There are no standard multimedia

platforms, however there are multimedia

standards on individual platforms.

Examples include QuickTime (originally

Apple), AVI, MP3, MPEG, JPG, GIF, PAL,

NTSC, etc.

25

What is multimedia?What is multimedia?

A computer-based interactive A computer-based interactive communications process that communications process that incorporates:incorporates:– text, text, – graphics, graphics, – sound, sound, – animation, and animation, and – video.video.

26

Why Multimedia?Why Multimedia?

User controlUser control IndividualizationIndividualization InteractivityInteractivity

27

Interactivity: the Key Interactivity: the Key ComponentComponent

Learner Control: The user Learner Control: The user determines what content is determines what content is delivered, when it is delivered, & delivered, when it is delivered, & how it is delivered.how it is delivered.

Nonlinear: Nonlinear: Linear:Linear:

28

Categories of Multimedia Categories of Multimedia TitlesTitles

EntertainmentEntertainment Education: A.D.A.M.Education: A.D.A.M. Corporate CommunicationsCorporate Communications

– Marketing & trainingMarketing & training– Presentations & trainingPresentations & training

ReferenceReference

29

Categories of Multimedia Categories of Multimedia Titles Titles (Continue)(Continue)

EdutainmentEdutainment TrainingTraining RecreationRecreation

30

Delivering MultimediaDelivering Multimedia

Compact Disc (CD)Compact Disc (CD) Digital Video (Versatile) Disc (DVD)Digital Video (Versatile) Disc (DVD) KioskKiosk Online (Internet & Intranet)Online (Internet & Intranet)

31

Multimedia Personal Multimedia Personal ComputerComputer

MPC: Level 1 (1990)MPC: Level 1 (1990) MPC2: Level 2 (1991)MPC2: Level 2 (1991) MPC3: Level 3 (1993)MPC3: Level 3 (1993)

– 8MB8MB– Pentium 75 MHzPentium 75 MHz– 540 MB Hard Drive540 MB Hard Drive– 4X Speed CD-ROM4X Speed CD-ROM– 640x480 Pixels Video Display (65,536 640x480 Pixels Video Display (65,536

colors)colors)

32

Playback SystemPlayback System

ProcessorProcessor MemoryMemory Monitor & Video CardMonitor & Video Card Audio CardAudio Card CD-ROM Drive & DVD-ROM DriveCD-ROM Drive & DVD-ROM Drive

33

Development SystemDevelopment System

ProcessorProcessor MemoryMemory Video capture cardVideo capture card MonitorMonitor

34

Development System Development System (Continue)(Continue)

PeripheralsPeripherals– ScannerScanner– External storageExternal storage

Zip drive (100 MB)Zip drive (100 MB) Jazz drive (1 GB)Jazz drive (1 GB)

– CD, DVD recorderCD, DVD recorder– Digital camera, Digital Video CameraDigital camera, Digital Video Camera– MicrophoneMicrophone– otherother

35

What is Multimedia?What is Multimedia?

• Human behavior – sensory, memory, reactionary

• Five senses – sound, touch, sight, taste, smell

• A combination of these provides a rich learning environment

• Only sound and sight can be captured in computer systems (why?)

36


• Sight and sound are captured in a computer system as video, audio, and data

• A medium refers to any one of data such as text, digitized voice, digitized video, still digitized images, and graphics.

37


Multimedia - is the combination of two or

more media.

38

User perspectiveUser perspective

• The user gets input in the form of data, voice, video, image, graphics, or a combination of these

• The user generates information in one or more of these media

39

User perspectiveUser perspective

USER

Data

Voice

Video

Image

Graphics

Data

Voice

Video

Image

Graphics

40

What is a Multimedia What is a Multimedia System?System?

• A multimedia system is characterized by the creation, processing, storage, manipulation, rendition and distribution of multimedia information

• Temporal relationship (time) between media makes multimedia different from normal data– synchronization

41

Multimedia System Multimedia System RequirementsRequirements

• Very high processing power - processing and movement of large amounts of data in real-time

• File system capable of handling multimedia information

• File formats that exploit the inherent properties of the multimedia information

42

Multimedia System Multimedia System RequirementsRequirements

• Efficient and high I/O rate• Multimedia operating system• Storage and memory• Network support• Software tools and applications

43

Analog vs Digital SignalsAnalog vs Digital Signals

• Voice, music – analog signal – continuous

• They must be digitized for computer manipulation

• Conversion is carried out by signal encoder

• Signal decoder

44

SamplingSampling

• E.g. voice can be sampled at 11 KHz, 22KHz, 44KHz

• Music has a higher range. • Human hearing 20-20,000 Hz• CD quality sound is 44KHz

45

QuantizationQuantization

• 1bit = 1 Binary Digit• 8 bits = 8b = 1 byte = 1B• 1000B = 1KiloBytes = 1KB• 1000KB = 1 MegaByte = 1MB• 1000MB = 1GigaByte = 1GB• 1000GB = 1 TeraByte = 1TB• …

46

Binary CodeBinary Code

Decimal Binary

1 0001

2 0010

3 0011

4 0100

5 0101

6 0110

7 0111

8 1000

9 1001

47

QuantizationQuantization

• The value of each sample is also represented digitally

• In the discrete domain not all the values of the continuous domain can be found

• How many bits are sufficient?• Music – 16 bits• Pictures – 24 bits

48

Types of MediaTypes of Media

• Discrete– Text– data– image– graphics

• Continuous– Audio– Video

49

Text and DataText and Data

• Numbers can be converted from decimal to binary

• Characters can be converted using a look up chart called ASCII

• Each character is assigned a decimal number e.g. A = 65

• Data files are usually small

50

GraphicsGraphics

• Graphics are constructed by the composition of primitive objects such as lines, circles, polygons, curves, and splines

• Each object is stored as an equation• Each object has a number of attributes

– shape– size– color (border)– color (fill)– shadow etc

51

GraphicsGraphics• Takes less space than bitmaps for

uncomplicated pictures• Not suitable for photographs with a

lot of shades etc.

52

ImagesImages

• Continuous-tone pictures are digitized

• Images are bitmaps• Divide the picture into pixels –

picture cells• E.g. 100 x 100• Each pixel has a n bit quantization• N = 1, 2, 4, 8, 16, 24

53

ImagesImages

Bits Number of colors

1 2

2 4

4 16

8 256

16 65536

24 16777216

54

ColorColor• Three primary colors - RGB• Additive color mixing leads to a color

gamut• eg. Black = 0R + 0G + 0B• Java applet to mix colorshttp://www.phy.ntnu.edu.tw/java/image/

rgbColor.html• Java applet to display color gamuthttp://www.cs.rit.edu/~ncs/color/

a_chroma.html

55

Aspect RatioAspect Ratio• Screen width / screen height

4

3

4/3 = 1.33

56

AudioAudio

• Sampling rate and quantization• Mono, stereo or surround (number of

channels)• CD specification• DVD specification

57

CD-DACD-DA• CD - Digital Audio• Stereo, 44KHz Sampling, 16 bit

quantization• 73 minutes of music on CD

58

Surround SoundSurround Sound• Mono - one channel• Stereo - Two channels• Five channel - Left , center,

right, left surround, right surround

59

VideoVideo

• Most colors of the visible spectrum can be constructed from three primary colors

• Red, Green, Blue RGB• Each uses an 8 bit representation• 256 levels of each color• Total 24 bit = 16 million colors

60

VideoVideo

• Frame rate – 12, 15, 25, 30 frames/sec

• NTSC video uses 30 frames / sec• NTSC has 4:3 aspect ratio

– Length/height = AR– 1, 1.33, 1.66, 1.85, 2, 2.5 etc.

61

Aspect RatiosAspect Ratios

62

Aspect RatiosAspect Ratios

63

Aspect RatioAspect Ratio

64

LetterboxLetterbox• When showing a widescreen movie

on a 1.33 screen, letterboxing is used to display the entire frame

65

Pan and ScanPan and Scan• Broadcast television uses pan and

scan to utilize the entire height of the screen thus losing information on the sides

Definition of MultimediaDefinition of Multimedia

Multi (Latin multus - numerous)Multi (Latin multus - numerous)

Media, medium (Latin medius, medium: middle, center, Media, medium (Latin medius, medium: middle, center, intermediary; Latin mediat: intermediary, means)intermediary; Latin mediat: intermediary, means)

Multiple types of information captured, stored, Multiple types of information captured, stored, manipulated, transmitted, and presented. manipulated, transmitted, and presented.

Specifically: Images, Video, Audio (+Speech) and TextSpecifically: Images, Video, Audio (+Speech) and Text

Related terms: hypermedia, hypertextRelated terms: hypermedia, hypertext

Problem: “hypertext”, “hypermedia”, “multimedia” so Problem: “hypertext”, “hypermedia”, “multimedia” so overused/generalized they now convey little meaningoverused/generalized they now convey little meaning

Top Ten Misconceptions about Top Ten Misconceptions about Multimedia ComputingMultimedia Computing

Ramesh Jain, founding chairman of Virage and CTO of Ramesh Jain, founding chairman of Virage and CTO of Praja, www.praja.com, presented the following “top ten” Praja, www.praja.com, presented the following “top ten” MISCONCEPTIONS list as part of his keynote speech at MISCONCEPTIONS list as part of his keynote speech at the ACM Multimedia Conference, Ottawa, Canada, the ACM Multimedia Conference, Ottawa, Canada, October 2, 2001:October 2, 2001:

10.10. Video = Multimedia.Video = Multimedia.

9.9. Multimedia = multi X separate medium.Multimedia = multi X separate medium.

8. 8. All information is ONLY in the images or video.All information is ONLY in the images or video.

7. 7. Editing of media is almost always off-line.Editing of media is almost always off-line.

6. 6. Query by example is best access method.Query by example is best access method.

Top Ten Misconceptions about Top Ten Misconceptions about Multimedia Computing, ContinuedMultimedia Computing, Continued

5.5. All users have PhDs in multimedia computing.All users have PhDs in multimedia computing.

4.4. Users have no memory or context.Users have no memory or context.

3. 3. Computers are for computing.Computers are for computing.

2. 2. Medium is the message.Medium is the message.

1. 1. We work for computers.We work for computers.

Ramesh Jain concluded his keynote talk with the Ramesh Jain concluded his keynote talk with the observation:observation:

Information Builds Experience, Experience is Life.Information Builds Experience, Experience is Life.

AudioAudio

ImagesImages

InformationInformationRetrievalRetrieval

StorageStorageSystemsSystems

NetworkingNetworking PsychologyPsychology

HCIHCI

DataDataCompressionCompression

NaturalNaturalLanguageLanguageProcessingProcessing

MultimedMultimediaia

CPU PowerCPU Power

VideoVideo

Multimedia PhysicsMultimedia Physics

• Sound is a waveformSound is a waveform

• Imagery is a waveformImagery is a waveform• light is electromagnetic radiation with different intensity in light is electromagnetic radiation with different intensity in

spatial coordinatesspatial coordinates• color corresponds to wavelength (red is the longest color corresponds to wavelength (red is the longest

wavelength visible by people)wavelength visible by people)

• Introductory treatment of “light behaves as both particle Introductory treatment of “light behaves as both particle and wave” at http://www.howstuffworks.com/light1.htm and wave” at http://www.howstuffworks.com/light1.htm

• ““Distributed Multimedia” by Palmer Agnew and Anne Distributed Multimedia” by Palmer Agnew and Anne Kellerman, published by Atomic Dog Publishing, Kellerman, published by Atomic Dog Publishing, http://www.atomicdogpublishing.comhttp://www.atomicdogpublishing.com

A Quick Introduction to Light WavesA Quick Introduction to Light Waves

• Derived from: Derived from: http://www.pbs.org/deepspace/classroom/activity2.htmlhttp://www.pbs.org/deepspace/classroom/activity2.html

• Waves characterized by wavelength and frequencyWaves characterized by wavelength and frequency

• Light is a type of electromagnetic radiation in a range for which our Light is a type of electromagnetic radiation in a range for which our eyes are sensitiveeyes are sensitive

• Sound is not electromagnetic radiation, but sound is a wave as well. Sound is not electromagnetic radiation, but sound is a wave as well. Higher pitches are caused by higher frequencies of vibrating Higher pitches are caused by higher frequencies of vibrating molecules that reach your eardrum. Lower pitches are likewise molecules that reach your eardrum. Lower pitches are likewise caused by lower frequencies. caused by lower frequencies.

wavelength

Wavelength/ Frequency SpectrumWavelength/ Frequency Spectrum

Long radio waves Microwaves X-rays Gamma rays

TV, FM Infrared Ultraviolet

700 nm 600 nm 500 nm 400 nm

4.5x1014 Hz 5x1014 Hz 6x1014 Hz 7x1014 Hz

Migration from Analog to Digital RepresentationMigration from Analog to Digital Representation

• Analog signals to sensorsAnalog signals to sensors• E.g. vinyl recordsE.g. vinyl records• Fidelity is faithfulness to the originalFidelity is faithfulness to the original

• Digital representation (1960s)Digital representation (1960s)• SamplingSampling• QuantizingQuantizing• CodingCoding

• Limiting factors in move to digital:Limiting factors in move to digital:• Storage limitsStorage limits• CPU speedsCPU speeds• I/O speedsI/O speeds• Network bandwidthNetwork bandwidth

Why Digital?Why Digital?

• Universal storage, transmission format Universal storage, transmission format

• CD, InternetCD, Internet

• Precision (range of values, number of bits, floating Precision (range of values, number of bits, floating point)point)

• Lossless transmission/storageLossless transmission/storage

BUT:BUT:

• Sampling rate distorts informationSampling rate distorts information

• Size requirements may be huge compared to analog, Size requirements may be huge compared to analog, e.g., 4.2 million pixels for single 35 mm photograph!e.g., 4.2 million pixels for single 35 mm photograph!

results in lots of work on perception-based lossy digital results in lots of work on perception-based lossy digital compression strategiescompression strategies

Why Perception MattersWhy Perception Matters

http://www.libertarian.on.ca/images/Florida%20Recount.jpghttp://www.libertarian.on.ca/images/Florida%20Recount.jpg

AudioAudio

• SoundsSounds• Hear 15 Hz to 20 kHzHear 15 Hz to 20 kHz• Speech is 50 Hz to 10 kHzSpeech is 50 Hz to 10 kHz

• Speech RecognitionSpeech Recognition• It is hard to wreck a nice beach / It is hard to recognize It is hard to wreck a nice beach / It is hard to recognize

speechspeech• Ice cream / I scream Ice cream / I scream

• SynthesisSynthesis• SpeechSpeech• Music Music

• MIDI for 127 instruments, 47 percussion soundsMIDI for 127 instruments, 47 percussion sounds

• Notes, timingNotes, timing

Speech Recognition IssuesSpeech Recognition Issues

• Continuous vs. discreteContinuous vs. discrete

• Vocabulary sizeVocabulary size

• Channel (microphone)Channel (microphone)

• Environment (location of microphone and speaker)Environment (location of microphone and speaker)

• Speaker dependent/speaker independentSpeaker dependent/speaker independent

• Context (language model)Context (language model)

• Interactivity (dialog model)Interactivity (dialog model)

Acoustic Modeling

Describes the sounds thatmake up speech

Lexicon

Describes which sequences of speech

sounds make upvalid words

Language Model

Describes the likelihoodof various sequences of

words being spoken

Speech Recognition

Speech Recognition Knowledge Sources

Speech Variations

Style Variations

careful, clear, articulated, formal, casualspontaneous, normal, read,

dictated, intimateVoice Quality

breathy, creaky,whispery, tense,

lax, modal

Context

sport, professional,interview,

free conversation,man-machine dialogue

Speaking Rate

normal, slow, fast,very fast

Stress

in noise, with increased vocaleffort (Lombard reflex),

emotional factors (e.g. angry),under cognitive load

VideoVideo

• Video is made up of framesVideo is made up of frames• Frame rate = delay between successive framesFrame rate = delay between successive frames• Minimal change between framesMinimal change between frames• Sequencing creates the illusion of movementSequencing creates the illusion of movement

• 16 frames per second (fps) is “smooth”16 frames per second (fps) is “smooth”

• Standards: NTSC 29.97 fps, PAL fps, HDTV 60 fpsStandards: NTSC 29.97 fps, PAL fps, HDTV 60 fps• InterlacingInterlacing

• Display scan rate is different Display scan rate is different • Monitor refresh rate, e.g., 60-70 Hz = ~1/secondMonitor refresh rate, e.g., 60-70 Hz = ~1/second

Captured vs. SyntheticCaptured vs. Synthetic

• Animation vs. VideoAnimation vs. Video

• Vector Graphics vs. Bitmap/Raster PicturesVector Graphics vs. Bitmap/Raster Pictures

• Synthesizer vs. RecordingSynthesizer vs. Recording

• Storage? Manipulation? Processor Requirements?Storage? Manipulation? Processor Requirements?

• Fidelity to real world Fidelity to real world

• Hybrids are possibleHybrids are possible

Why is Multimedia Important?Why is Multimedia Important?

• Our society -Our society -• captures its experience,captures its experience,• records its accomplishments,records its accomplishments,• portrays its pastportrays its past• informs its massesinforms its masses…………in pictures, audio and videoin pictures, audio and video

• For many, CNN has become the “publication of record”For many, CNN has become the “publication of record”

• Multimedia learning leverages “multiple intelligences”Multimedia learning leverages “multiple intelligences”

• Multimedia Digital Libraries are an essential component Multimedia Digital Libraries are an essential component ofof• formal, informal, and professional learningformal, informal, and professional learning• distance education, telemedicinedistance education, telemedicine

Technology Push vs. Market PullTechnology Push vs. Market Pull

• Home EntertainmentHome Entertainment

• Catalog OrderingCatalog Ordering

• Multimedia Training, EducationMultimedia Training, Education

• VideoconferencingVideoconferencing

• Professional Video ServicesProfessional Video Services

• VideomailVideomail

• Speech RecognitionSpeech Recognition

Hype vs. RealityHype vs. Reality

What is feasible, under what circumstances?What is feasible, under what circumstances?

What is possible?What is possible?

What is impossible?What is impossible?

What is unlikely?What is unlikely?

4 multimedia basics

Technology

Transcript of 4 multimedia basics