MIS Lesson4 Multimedia

Topics Multimedia Production Systems Multimedia Objects Digital media forms/objects Multimedia: Social Impact Multimedia Application Business Education Image, Audio & Video Capture Storage and Compression standards Selection Of Multimedia Software Multimedia Software (Practical) Presentation: PowerPoint Web-Design: Dreamweaver Graphics: Paint or Firework Animation: Flash David Asirvatham LESSON 4 -

Multimedia What is Multimedia? Digital media presented in an interactive manner Multimedia Objects (Media forms) Text (one page = 500-1,000 Bytes) Graphics (one pic = 300KB - 1MB) Audio (one min. = 2.5MB) Animation (size varies) Video (one min. = 10MB) Human faculties sight sound touch smell taste David Asirvatham LESSON 4 -

Digital Text Printed text e.g books, newspaper Scanned text image OCR software needed to convert to machine readable Electronic text machine readable form can be electronically transmitted or edited Hypertext text that has been linked used widely in Internet David Asirvatham LESSON 4 -

Digital Images Pixel: Picture Element Screen: 1280 by 1024 pixel dpi are used for output devices rectangular array of pixels: bitmap (or raster) images can be represented in bitmap or vector graphics Vector graphics: scalable, size & shape can be changed Raster requires recalculation and redrawing when changes are made Most Multimedia graphics are raster (faster to display) Font technology makes use of vector graphics David Asirvatham LESSON 4 -

Image and pixels David Asirvatham LESSON 4 - Enlarged Image Original Image

Digital Colour Images Black & White, Grayscale and Colour images Human eye can distinguish between 0.5 - 2 million colours Video/image display: 2 1 (2 colour) to 2 24 (16.7 million) 4-bit and 8-bit colour: indexed colour 16-bit and 24-bit colour: true colour image Common Graphics format .bmp bitmap; Most efficient format for windows .gif graphics interchange format; Used in Internet .pcd Kodak’s photo CD .mac Macintosh MacPaint .jpg Joint Photographic Experts Group; platform-independent .tif Tagged Image File; have many different subformat Others: .pic (PC Paint); .pcx (Zsoft Paintbrush); .wpg (WordPerfect) David Asirvatham LESSON 4 -

Raster vs Vector Raster or Bitmap Images image is created as a set of points each point can display 2 to millions of colour 1 bit = 2 colour 4 bit = 16 colour 1 B = 256 colour 2 B = 65,536 colour 3 B = 16.7 million colours std VGA display is 640 x 480 pixels = 307,200 pixels David Asirvatham LESSON 4 -

Raster vs Vector Vector Images based on drawing elements or objects such as lines, rectangle, circles, etc e.g. Line: x1,y1,x2,y2,colour e.g Circle: x1,y1,radius, fill_colour, line_colour can be resized/scaled limited level of details that can be represented David Asirvatham LESSON 4 -

Digital Audio Human hearing: 20Hz - 20KHz Three classes of digital audio waveform files can be copies and edited sampling rate (e.g. 48 KHz) resolution (8 bit, 16 bit, etc) Sampling methods PCM: Pulse Code Modulation (equal width sampling) ADPCM: Adaptive Differential PCM (variable width sampling) CD audio two formats: music CD and CD-ROM storage (e.g. Waveform) MIDI (Musical Instrument Digital Interface) can synthesizes music via a command and timing system many keyboards, drum machines and effects boxes have MIDI port David Asirvatham LESSON 4 -

Digital Audio Signal Rate Bandwidth Music CD 44.1KHz 20Hz - 20KHz FM Radio 32KHz 20Hz - 14KHz Telephone 8KHz 180Hz - 3.4KHz David Asirvatham LESSON 4 -

Digital Audio: A/D Converter & Sampling David Asirvatham LESSON 4 - Stored: 5 7 8 12 …….. or 0101 0111 1000 1100 Time

Digital Storage A page of text: 8KB One second of stereo sound: 22KB Colour photo/image: 500KB One second of video: 22MB Compression techniques are used to store images, audio and video Common storage devices Floppy disk: 1.44MB HDD: 2-6 GB CD-ROM: 650MB Tapes David Asirvatham LESSON 4 -

Why Digital Format? Analog signals generated by voice are complex. It is continuous. A digital signal is simpler it is discrete. Advantages of Digital Format Better integrity because there is less variation. Higher capacity and more efficient multiplexing Easier Integration of voice, data, and video signals Better security and privacy through encryption Lower cost David Asirvatham LESSON 4 -

Multimedia: Societal Issues Information, business, education, Games, entertainment, pornography, Internet addiction, privacy, censorship, encryption, etc Cyber Law Patent, Copyright, Fair use (comments, teaching, news, criticism), Data protection act, Digital Signature Act, Multimedia Act, Telemedicine Act, Organisation Impact flatter organisation, improved communication, change in advertising, change in workplace, employees have greater empowerment, more efficient, less paper, more complex tools & easy to use, Virtual environment David Asirvatham LESSON 4 -

Multimedia & Internet What is Internet? is a worldwide network of connections between computers it is a huge collection of computers, cables, software and poeple allows data to be transmitted from one computer to the other it operates using TCP/IP (Transmission Control Protocol/Internet Protocol) refer to presentation 2 David Asirvatham LESSON 4 -

Multimedia Applications Virtual Shopping Music & Movies Video Conferencing Training Marketing Telemedicine Manufacturing Discussion How can multimedia contribute in these areas? What are the benefits and drawbacks? David Asirvatham LESSON 4 -

Multimedia in Business Marketing and advertising Web-based, cheaper, Training & Education Office environment technology based, EDI E-commerce (Web-based sales & transactions) larger customer base, easy to setup, less need for showrooms & sales personal, server admin., delivery service, web-page & database design, new strategies for marketing, customer service, & number of hits E-Money (e-cheque, e-purse, e-cash, etc) Payment modes, security, e-bank, customer confidence, use of smartcard (microchip) or biometric, David Asirvatham LESSON 4 -

Multimedia in Business Virtual shopping desktop videoconferencing Financial Services Stock report (www.sec.gov) & news (www.pointcast.com) Real estate Corporate Training (widely used) Advertising and electronic brochures Mass market applications e.g hair styles, dressing, etc (www.webcreations.com/styles) David Asirvatham LESSON 4 -

Multimedia in Training & Education Learning thro’ experience (rather than an event) learner oriented (speed, time, place) learner decides what he/she wants to learn (with some control) learner can do self-assessment sufficient practice may be provided post-training support can be provided Method Average retention Lecture 5% Reading 10% AV 20% Demo 30% Discussion (Group) 50% Doing 75% Teach & use immediately 90% David Asirvatham LESSON 4 -

Multimedia in Education New and innovative learning tool Multimedia is not cheap, but some natural settings are much more expensive e.g. training a pilot, surgical procedure, view an explosion, Multimedia become cost efficient when audience change but the message remains the same can be time and location independent David Asirvatham LESSON 4 -

Benefits of Interactive Multimedia Education Training is available when needed Consistency every user is exposed to the same information Simulation Learner can operate or troubleshoot Recordkeeping and analysis information of the learner can be recorded and analysed (e.g. test) Flexibility can be used as reference tool or as the main tool; small or large groups Reduce training time studies have indicated a reduction of 30% (less time in training & organising) Others: motivation, adaptability to learner, improves retention level David Asirvatham LESSON 4 -

Drawback of Multimedia Training commitment different delivery methodology is needed require high initial resources change in technology David Asirvatham LESSON 4 -

Image Quality Image Quality will depend on Resolution Colour Depth Computer Generated Colour Hue: vector value moving from 0-360 degree on a colour wheel Saturation: 100% is pure colour, 0 is black/white Brightness: A pure colour has 50% light: 100% is white; 0% is black Calculate the file size of an image that is 800x600 pixels and has 65,536 colours Compression format: GIF, TIFF, JPEG, etc. David Asirvatham LESSON 4 -

Audio Capture PC sound card can capture audio and digitise it Audio editing software allows to mix several soundtrack microphone stereo quality of sound card (16 bit, 32 bit, etc) Audio Compression PCM (Pulse Code Modulation) AIFF (Audio Interchange File Format) U or Mu-Law (NeXT/Sun format; multiplatform: Mac, PC & Unix) Wav (Microsoft) MPEG ADCPM (Adaptive Differential PCM) David Asirvatham LESSON 4 -

Digital Sound The three characteristics for recording sound Frequency rate (std: 44.1KHz, 22.5KHz or 11.025KHz) Amplitude (e.g 8-bits = 256 level; 16-bit for 65,536 level) Sound channel (1 channel=mono and 2 channel=stereo) Calculate the file size for 1 min, 44.1KHz, 16-bit stereo sound File size = 10.584MB Digital audio software support Playback, Record, Stop, FF, FR, Rewind Editing Audio Trimming, volume adjustment, Resampling, Fade-in/out, Digital Signalprocessing, etc David Asirvatham LESSON 4 -

Video Capture Video capture card source can be a VHS player or video camera frame rate: for 30 fps, high quality video capture card will be needed support: composite video signal, S-video compression: MPEG or motion JPEG high processing power computer needed; high RAM (graphical workstations) storage: HDD, CD-ROM, Optical storage Editing software David Asirvatham LESSON 4 -

Analog video Analog video: NTSC (National Television Std. Committee) Use in Japan and US 525 scan lines drawn every 1/30th second Scanned at 60 cycles per second (Hz) Interlacing (two passes) PAL (Phase Alternate Line) UK, Europe, Australia 625 lines drawn every 1/25 sec Interlaced at 50 cycles per second (Hz) SECAM (Sequential Colour with Memory) – {French} 625 lines Interlaced at 50 cycle per second (Hz) HDTV 1,125 lines at 60 Hz David Asirvatham LESSON 4 -

Digital Video Digital video characteristics Frame rate (e.g. 24 fps) Frame Size (e.g. 640 x 480) Colour Depth (e.g 24-bit colour) Calculate the file size for a 30fps 640 x 480 size digital video with 65,535 colours Compression Lossless Quality is the same as original Lossy The quality differ from the original Intraframe Each frame is compressed individually and stored Interframe Only changes are stored David Asirvatham LESSON 4 -

Examples of Firewire Interface Firewire is Apple's version of the IEEE-1394 interface specification. It is also known as Sony's i.LINK,®. Whether referred to as FireWire, IEEE-1394 or iLINK the interface is the only high-speed digital technology that enables consumer electronics to easily interface with computer products David Asirvatham LESSON 4 - Firewire

Compression Advantages of compression reduce file size reduce cost of storage, transmission & processing Sampling theory sampling rate (e.g audio: 44.1 KHz) Nyquist Theorem: one must sample twice as fast as the highest frequency being sampled Techniques of Compression Lossy (changes the original data on decompression) changes are indistinguishable to human eye (JPEG, MPEG) ratio can be as high as several hundred is to one Lossless (original data is not changed on decompression) pkzip, best ratio is 2:1 David Asirvatham LESSON 4 -

Lossy Lossy compression compresses a file so that when it's later decompressed, it appears to be the same. But it isn't. some brilliant algorithms delete some data from the file in such a way that when the file is later reconstructed, you don't notice the deletions JPEG is lossy while TIFF is lossless David Asirvatham LESSON 4 - Original Picture Uncompressed 29MB High Quality 73KB Low Quality 25KB

Image Format (All 24 bit) David Asirvatham LESSON 4 - Bitmap 538KB GIF 84KB JPEG 38KB TIFF 509KB

Image JPEG format David Asirvatham LESSON 4 - 100% 92KB 80% 32KB 60% 16KB 40% 11KB

Major Compression Std. JPEG (Joint Photograhic Experts Group) Compression Standard for continuous-tone still image 24-bit colour or gray-scale Primarily for still image (can also be used for video) lossy (image obtained out of decompression isn’t identical) useful for human but not for machine-analysis degree of lossiness can be varied by parameter (good for trade off of file size) MPEG ( Moving Picture Expert Group) colour video and audio compression JPEG compress data within a frame while MPEG can exploit the similarity of adjacent frames constant bit rate (suitable for streaming or transmission) David Asirvatham LESSON 4 -

Major Compression Std. Graphics Interchange Format (GIF) developed by Compuserver used widely in the web uses LZW compression algorithm (by Unisys) limited to 256 colours Tagged Image File Format (TIFF) very high compression capability good for black & white image used in publishing and fax David Asirvatham LESSON 4 -

Video Compression MPEG digital video standard delta-frame encoding (only changes from frame to frame will be recorded) CD, cable TV, satellite broadcast, HDTV, etc MPEG 1 non-interlaced (draws every line) for playback from CD-ROMs MPEG 2 interlaced version (draws every other line) broadcast quality used by US Grand Alliance HDTV, European Digital Video Broadcast Group, RCA (Direct TV), etc MPEG 3 suppose to be HDTV standard but MPEG 2 could fulfill the needs (e.g. scaling the bit rate) David Asirvatham LESSON 4 -

Examples of Multimedia Software Authoring Macromedia Authorware, CBT Express, Director 4.0, Multimedia Workbench, Toolbook, Quest, etc Graphics CorelDraw, PhotoPaint, MacDraw, Photoshop, Professional Draw, Studio/32, Painter, Firework, etc Animation 3D Studio, Animation Master, Macromedia Flash, Vision 3D, Visual Reality, Imagine, etc Presentation Harvard Graphics, PowerPoint, Lotus Cam, etc Digital Audio Editing Roland Audio tools, SoundEdit, WAVE, Studio Vision, etc Video Editing Quicktime, VideoFusion, VideoShop, Premiere, etc. David Asirvatham LESSON 4 -

Selection of Multimedia Software User friendly Compatibility (platform, other packages) Editing facilities Text option (size, colour, font) Graphics option (format, import/export, animation) Media option (interface with various peripherals) Interactivity (branching, menu, hot spots) Management capabilities (database, folder organisation) Cost (incl. Upgrades) Others: Support, Reliability, number of users, hardware & memory requirements, training, installation, Documentation, etc David Asirvatham LESSON 4 -

MIS Lesson4 Multimedia

More Related Content

What's hot (19)

Similar to MIS Lesson4 Multimedia (20)

More from David Asirvatham (20)

Recently uploaded (20)

MIS Lesson4 Multimedia