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MULTIMEDIA. Multimedia :. It is the field concerned with the computer-controlled integration of text , graphics, drawings, still and moving images (Video), animation, audio , and any other media where every type of information can be
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Multimedia : It is the field concerned with the computer-controlled integration of text, graphics, drawings, still and moving images (Video), animation, audio, and any other media where every type of information can be represented, stored, transmitted and processed digitally
MULTIMEDIA PC SPECIFICATIONS: • MULTIMEDIA PC marketing council established multimedia specification • First MPC standards were set in 1990 • Second level in 1993 • Third level in 1996
THIRD LEVEL MPC SPECIFICATIONS: • PROCESSOR - 75 MHz , PENTIUM • RAM MEMORY – 8 MB • HARD DISK SPACE – 540 MB • DISPLAY SYSTEM – 352 X 240 at 30 FRAMES/SEC, 16- bit colour • CD Drive - 4 x (quad speed) drive using no more than 40% CPU to read , with <250 ms seek time • SOUND CARD – Outputting 44 KHZ, 16 bit CD quality sound • ENVIRONMENT- Windows 3.11 • MPEG -1 hardware or software video playback
VISUAL ELEMENTS: • Data in multimedia applications should be digitized before displaying on screen • Methods Of Digitizing: • Bit Mapped Method • Vector Graphic Method
Bit mapped method • It stores, manipulates and represent images as rows and columns of screen pixels. • File formats of bit-mapped data is given by: • Windows Bit Map(BMP) • Joint Photographic Group(JPG) • Tagged Image File Format(TIFF) • Graphical Interchange Format(GIF) • PC Paintbrush(PCX)
Vector Graphics method • Mathematical formulae will be used to recreate images Advantages: • Resolution Independent • Reproduce easier and faster • Better appearance on screen compared to bit map • Less storage space • Easy to retrieve from storage media Applications: • CAD/CAM systems • Rapid prototyping(RP) systems
Vector Graphics method ( cont…) • File Formats: • Encapsulated Postscript(EPS) • Window Metafile Format(WMF) • Hewlett-Packard Graphics Format(HPGL) • Macintosh graphics (PICT) • Autodesk DXF CAD
EDITING: • Both animations and pre recorded segments can be edited • This requires special graphics components and software EX : Video Editing Software (i) Cinelerra (ii) Kino (iii)VirtualDub (iV)VirtualDubMod (V)Adobe After Effects
EX :- Audio Editing Software: (i)Ardour (ii) SOX (iii)LMMS (iv)Ecasound
INTERNET: • It is most widely used multimedia application • Web pages are written in HTML language • HTML text contains • Content • Mark up Tag • Links • Forms • Web browser will be used to access webpages
Windows Bit Map(BMP): • It was jointly introduced by windows and IBM companies. • Later on it is suitable for all platforms • FEATURES: • Simple file structure • Easy to handle • Binary file format
Structure of BMP • It contains 4 sections: (i) File Header (ii)Image header (iii)Colour table (iv)Pixel data
File Header: • To confirm that file is Windows BMP file • Size of file • Location of image data stored in file • Size of file is 14bytes
Image header • It stores • Image • Data Format : Height Width No of bits/pixels compressibility of image data
Colour Table: • Optional field • For 24 bit image – colour table is ABSENT If present it is either colour palette or set of bit masks
Pixel Data: • Remaining part of file is completely pixel data • Pixel data format - scan line padded with 32-bit boundary(4 byte)
PCX File Format: • Established by Zsoft to support PC paint brush software • It is used by • IBM computers • computer games • other graphics utilities in early DOS PCs
Many versions of PCX were released but failed due to some reasons • Version 5.0 PCX file format is now supported by many PC software
Structure of PCX format: • Header • Image data Header:- • It stores information about image • Palette section will be end of file • Palette will be present only if PCX supports(colours <=16)
Image data:- • It contains two types of information: • Length(max 64 bytes) • Colour- value from palette table
SOUND ELEMENTS • Sound elements can also be recorded and generated through computer programs • Sound recorder is capable of performing following tasks. • Recording • Editing recorded sound • Deleting unwanted parts • Inserting and Superimposing selected sound into existing sound file
Audio File Formats: Ex: • Waveform(WAV)- Store actual sounds Bigger than MIDI file • MPEG Layer III(MP3)- Store instructions(SYNTHESIZERS) Smaller than WAV file • Musical Instrument Digital Interface(MIDI)
WAV AND MP3 FILE FORMATS: • Waveform Audio File Format • WAVE, or more commonly known as WAV due to its filename extension • Windows native file format • WAV is most popular format for storing audio data • WAV is compatible with all modern programs • Though a WAV file can contain compressed audio, the most common WAV audio format is uncompressed audio in the linear pulse code modulation (LPCM) format
Wave files will be separated into groups called “CHUNKS” • Each Chunk contains: • Header • Data bytes • Structure of chunks help in skipping of any particular one and continue with others. • Any extra space in chunks will be padded with zeros.
MP3 File Format: • MP3 was designed by the Moving Picture Experts Group (MPEG) • MPEG Audio Layer III • USES: (I)Consumer audio streaming or storage (ii)Digital audio compression for the transfer and playback of music on most digital audio players
It is arranged in the form of FRAMES similar to chunks • Frames are independent items • Each frame have Header and audio information
MULTIMEDIA STORAGE: SOURCE OF SOUND • SOUND SYSTEMS: SOUND WAVES ELECTRICAL SIGNALS STORAGE & PLAYBACK
STORAGE & PLAYBACK : • It is done by hardware devices Ex: Floppy Disks DVD CD Optical compact disk Magnetic cassette Tapes
Floppy disk: • A floppy disk, also called a diskette or just disk • It is a type of disk storage composed of a disk of thin and flexiblemagnetic storage medium • It is sealed in a rectangular plastic carrier lined with fabric that removes dust particles. Floppy disks are read and written by a floppy disk drive (FDD).
DVD(Digital video disc): • It stores any kind of digital data and is widely used for software and other computer files as well as video programs • DVDs offer higher storage capacity than CD while having the same dimensions • Storage - 4.7 GB for a single-layered, single-sided disc 8.5 GB for a dual-layered, single-sided disc
CompactDisk(CD): • It is a digitaloptical disc data storage format • Optical storage provides more capacity than analog devices • The format was originally developed to store and play only sound recordings but was later adapted for storage of data (CD-ROM).
Standard CDs have a Diameter- 120 millimetres (4.7 in) Storage- 80 minutes uncompressed audio or about 700 MB of data Thickness – 1 mm • Mirror like gold or silver Polycarbonate layer is coated on CD • Data is impressed on Polycarbonate layer
Working of CD: • Writing : • Digital data should be made ready • Optical disk will be exposed to laser light pulses as disk spins • Microscopic pits will be made on disk(encoded form of information) directly
Reading: • Low intensity laser scanner is used to retrieve data from disk • Intensity of light reflected back from pits or flat surface will be noted Pit-1 Flat-0 • Circuitry in CD drive converts digital signals to electrical signals
Types Of CD: • CD-R (Compact Disc-Recordable) -A CD-R disc is a compact disc that can be written once and read arbitrarily many times. • CD-RW(Compact Disc-Rewritable)are rewritable CD's that can be re-written a dozen or more times, the content can be copied, deleted and modified as necessary
Blu-ray or Blu-ray Disc (BD, BRD) • It is a digital optical disc data storage format. • It was designed to supersede the DVD format, in that it is capable of storing high-definition video resolution (1080p). • The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs
Compact Cassette • It is also called cassette tape, audio cassette, or simply tape or cassette • Compact Cassettes contain two miniature spools. • Between spools a magnetically coated, polyester-type plastic film is passed and wound. • These spools and their attendant parts are held inside a protective plastic shell.
Two stereo pairs of tracks are available on the tape • One stereo pair or one monophonic track is played or recorded when the tape is moving in one direction • The second pair when moving in the other direction. This reversal is achieved either by manually flipping the cassette