What is Multimedia
• Derived from the word “Multi” and “Media”
• Many, Multiple
• Multiple means by which information is
stored, transmitted, presented or perceived.
• E.g. text, photographs, maps, sound, video etc.
Definition of multimedia
• Multimedia is a combination information in
the form of
text, graphic, sound, animation, and video
that is delivered interactively to the user by
Sound Effect Music
Goals & Objectives
• Re-engineering of existing application.
• Interactive tools
• Open solutions (portable).
• Bidirectional communication.
• To produce cost effective solutions.
• More work in less time.
• Centralized information.
• System capable of processing multimedia data
– Must be computer controlled.
– Integrated components.
– Information must be represented digitally.
– Computer system, commn. n/w, display
devices, capture devices, storage devices.
Limitation of Traditional Input Device
• Keyboard most common input device
– evolution simple , numeric alphanumeric and multifunction
• GUI pointing device mouse or pen
– essential for selecting and moving graphical objects.
• Traditional multimedia variety of other types of input.
• Only Text initially no measure of quality normal dot
• high quality of text, text color, text attributes advanced
printer like laser printer.
• Data inputs like audio or voice, full motion video, still
photos and images etc require special device like digital
pens ,video cameras , image scanners
Digital v/s Analog
• Need to convert analog to digital.
– E.g. scanning image
• For full-motion video and audio, most i/p
devices produce analog while computer can
process only digital. (e.g. microphone)
• Coding & Decoding process.
• Hardware devices and software programs that
perform this function are called codecs.
– It includes compression and decompression algos.
• An input device that allows the user to point, write, draw
• Gesture allows user to select and act upon the object.
– Natural device for unskilled or partly skilled person.
– Can be used as a pointing device.
– Small in size
– Can be used for palmtop computers (PDAs), notebooks etc.
– Allows adding annotations to forms and documents.
The digital pen captures and stores writing.
The writing is sent via USB or Bluetooth
• Light pen input device used with CRT
display to point at items on the screen or to
draw new items or modify existing ones.
• The light pen had a photo sensor at the tip.
• Photo sensor o/p amplified shaped fed
to flip flop whose status is (set)
• Whenever status flip flop is !comp is
interrupted and reads coordinates of points
where light is touched on screen
Uses of light pen
• Can use instead of keyboard to request further
• Provide quick response to operator inquiry
• Used as input device in CAD application
• Write and sketch on the screen of CRT
• Types of scanner:
– Flatbed Scanner
– Sheet fed Scanner
– Drum Scanner
– Hand held Scanner
Musical Instrument Digital Interface
• Protocol that enables computer, synthesizers, keyboards
and other musical device to communicate with each
• Has been widely accepted and utilized by musicians and
• 16 channels of information, each of which can be routed
to a separate device.
• MIDI messages are unidirectional.
• An extra sound cable is necessary for 2-way
• No error detection capability.
• Max cable limit is 15 meter
• MIDI connector
• MIDI ports
– THRU (allows data to be forwarded to another instrument)
• Multiply devices can be connected in a daisy chain maner
• MIDI components:
– Sequencer (storage server / s/w music editor)
• MIDI Message
Status byte Data byte
Data byte 1 Data byte 2
and Function to be
• Classification of MIDI messages
• Channel Messages:
– Applied to specific channel
– Channel number is included in the status byte for these messages
– Classified into:
• Voice Messages:
– Carry musical performance data
– Instruct the receiving instrument to assign particular sounds to its voice
• Mode Messages:
– Affects the way the receiving instrument responds to incoming channel voice
• System Messages:
– Not channel specific, affect the system as a whole, e.g. timing signal for
– No channel number is specified in their status byte
– Classified into:
• Common Messages:
– Intended for all receivers in the system
• Real-Time Messages:
– related to synchronization
– To synchronize all of the MIDI clock-based equipments within a system, like
• Exclusive Messages:
– Related to things that cannot be standardized, like patch parameters or
Video Display Technology
• Display Terminologies:
– Drift (image moves up in a very slow motion)
– Jitter (image jumps at high rate)
– Swim (a sort of shadow image move from top to
• first practical means of transmitting document images
over a telephone line.
• The basic technology, now widely used, has evolved to
allow higher scanning density for better-quality fax.
• standardized at a very early stage to CCITl Group 3
compression standards (RLL).
• Typical pixel densities used for facsimile are in
the 100 to 200 dpi (pixels/inch) range.
• used for storing business documents that must be
retained for long periods of time or may need to
be accessed by a large number of people.
• Removes the need for making several copies of
the original for storage or distribution.
• Usually 300 dpi
• For gray scale or color, the sizes are larger to
accommodate the color information.
– Normally 400 dpi
Geographic information system maps (GIS)
• being used widely for natural resource and
• Two kinds of technologies are used for storage
and display of geographic maps.
• Raster storage allows a map to be displayed on a
graphical display system just like any other GUI
• applications consist of road maps and area maps (used to
track natural resources).
• Attribute data is assigned and identified, usually by map
• Another application combines raster images that have the
basic color map and a vector overlay showing the railroads
or highways and other human-made structures, and text
display showing attributes of features in the map.
• Full-motion Stored and Live Video
• Holographic Images
• Audio messages
• Video messages
• Document Image
• Image Processing and Image Recognition
– Image recognition
– Image enhancement
– Image reconstruction
– Image animation
– Image annotation
• Optical Character Recognition (OCR)
• Handwriting Recognition
• Full Motion Digital video applications
• Electronic Messaging
Multimedia Systems Architecture
Graphical User Multimedia
O.S. Software Multimedia
Drivers Driver Support
System hardware Add-on multimedia
(Multimedia-enabled) devices and peripherals
Fig: Multilevel architecture based on interface bus
Multimedia Interface bus
Multimedia Data Interface Standards
• Earliest and simplest formats used were:
– Intel’s DVI (Digital Video Interface)
– Apple’s Quicktime
– Microsoft’s AVI (Audio Video Interleave)
• Intel’s DVI
– Processor-independent specification for video interface
• Apple’s Quicktime
– Designed by Apple computers, to support multimedia applications
– Capable of handling various formats of digital
videos, pictures, sounds, panoramic images.
– Video file formats
• QuickTime movie (mov), MPEG-2,4 , AVI, 3GPP
– Audio file formats
• iTunes audio, MP3, WAV, AMR.
• Microsoft AVI:
– Offers low-cost, low-resolution video processing
– Suitable for average desktop users
• Primary Storage Media:
– Temporary storage
– Types: RAM, ROM, PROM, EPROM, EEPROM
• Random Access Memory:
– Temporary storage
– Programs can be loaded from outside and executed.
– Larger the RAM better the performance.
– Volatile memory.
– Stores data and instructions that are frequently used by the
– Instructions in RAM constantly changes, depending on the
need of the CPU.
• DRAM and SRAM.
– Contains inst. Which are activated each time the computer is
– ROM inst. Performs POST check.
– Instruction can not usually be changed.
– Instructions are built into the electronic circuits of the chips.
– Access to info is random.
• Programmable Read Only Memory (PROM)
– Not economically feasible.
– Are blank ROM that can be programmed using special
– Suitable for development work.
– Not programmed during manufacturing but are custom
programmed by the user
– One time programmable
– More flexible and convenient than ROM.