Download - 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
Introduction to 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.
3Types of Multimedia
Introduction to Multimedia
Dynamic Media
Examples: Animation, video, audio, etc.
4Types of Multimedia
Introduction to Multimedia
Interactive Media
Examples: Animation, Web sites, CD/DVD authoring, software programming, etc.
5Types of Multimedia
Introduction to Multimedia
Animation
6Types of Multimedia
Introduction to Multimedia
Digital Video
7Types of Multimedia
Introduction to Multimedia
Digital Audio
8Types of Multimedia
Introduction to Multimedia
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
Introduction to Multimedia
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
Introduction to Multimedia
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
Introduction to Multimedia
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
Introduction to Multimedia
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
Introduction to Multimedia
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
Introduction to Multimedia
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]
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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)
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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.
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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)
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Applications of Multimedia Games Industry - PC, Video console, etc. Entertainment – Television, movies Education – Educational software, interactive
programs Training and Development
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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
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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)
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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.
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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.
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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.
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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.
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Why Multimedia?Why Multimedia?
User controlUser control IndividualizationIndividualization InteractivityInteractivity
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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:
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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
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Categories of Multimedia Categories of Multimedia Titles Titles (Continue)(Continue)
EdutainmentEdutainment TrainingTraining RecreationRecreation
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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)
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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)
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Playback SystemPlayback System
ProcessorProcessor MemoryMemory Monitor & Video CardMonitor & Video Card Audio CardAudio Card CD-ROM Drive & DVD-ROM DriveCD-ROM Drive & DVD-ROM Drive
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Development SystemDevelopment System
ProcessorProcessor MemoryMemory Video capture cardVideo capture card MonitorMonitor
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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
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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?)
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What is Multimedia?What is Multimedia?
• 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.
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What is Multimedia?What is Multimedia?
Multimedia - is the combination of two or
more media.
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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
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User perspectiveUser perspective
USER
Data
Voice
Video
Image
Graphics
Data
Voice
Video
Image
Graphics
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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
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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
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Multimedia System Multimedia System RequirementsRequirements
• Efficient and high I/O rate• Multimedia operating system• Storage and memory• Network support• Software tools and applications
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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
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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
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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• …
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Binary CodeBinary Code
Decimal Binary
1 0001
2 0010
3 0011
4 0100
5 0101
6 0110
7 0111
8 1000
9 1001
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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
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Types of MediaTypes of Media
• Discrete– Text– data– image– graphics
• Continuous– Audio– Video
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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
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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
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GraphicsGraphics• Takes less space than bitmaps for
uncomplicated pictures• Not suitable for photographs with a
lot of shades etc.
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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
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ImagesImages
Bits Number of colors
1 2
2 4
4 16
8 256
16 65536
24 16777216
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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
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Aspect RatioAspect Ratio• Screen width / screen height
4
3
4/3 = 1.33
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AudioAudio
• Sampling rate and quantization• Mono, stereo or surround (number of
channels)• CD specification• DVD specification
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CD-DACD-DA• CD - Digital Audio• Stereo, 44KHz Sampling, 16 bit
quantization• 73 minutes of music on CD
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Surround SoundSurround Sound• Mono - one channel• Stereo - Two channels• Five channel - Left , center,
right, left surround, right surround
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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
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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.
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Aspect RatiosAspect Ratios
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Aspect RatiosAspect Ratios
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Aspect RatioAspect Ratio
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LetterboxLetterbox• When showing a widescreen movie
on a 1.33 screen, letterboxing is used to display the entire frame
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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?