Intermediate 1 Multimedia

What is multimedia? In computing multimedia is the presentation of information by the computer system using text, sound and graphics.

Who uses multimedia? Education  In education multimedia can be used as a source of information. Students can search encyclopedias such as Encarta  Teachers can use presentations in order to make the lesson more interesting

Business  Multimedia is used for advertising and selling products on the Internet.  Some business use multimedia for training where CD-ROMs or on-line tutorials allow staff to learn at their own speed.

Leisure  People use the Internet for a wide range of reasons, including shopping and finding out about their hobbies  Many computer games use sound, 3D graphics and video clips

Written Task Multimedia Booklet Page 7 Exercise 1

A multimedia Presentation A basic multimedia system includes input devices, output devices, memory, backing storage and a variety of software.

Input devices and software Keyboard and mouse Scanner Microphone Graphics Tablet Digital Camera Video Camera

Keyboard and Mouse This is used for text entry, a standard QWERTY keyboard and mouse are needed

Scanner This allows the input of drawings, photographs or text directly in to the computers memory. Optical Character Recognition Software (OCR) OCR software has a limited number of characters it recognises, and therefore mistakes in scanned text are common.

Microphone It can be used to allow sound to be entered into a computers memory. Most computers have an in-built microphone. Voice Recognition Software This is the software that allows the user to enter text by speaking rather than typing

Voice Recognition Software Voice Recognition Drawbacks The user must speak slowly and clearly to allow the software to recognise all the words. The software has difficulty with strong accents and the user may need to repeat words and phrases

Graphics Tablet A graphics tablet has a pen or pointer connected to a flat board, which is sensitive to pressure. Handwriting Recognition Software This allows the user to write in his or her normal handwriting. The software reads the shape of the writing and converts it into text. (smart boards have this software, I will let you try it)

Digital Camera Photographs can easily be saved into the computers memory using a cable (USB) Resolution This is the amount of detail in an image, the higher the resolution the better the picture quality, but the less pictures that you can take.

Written Task Multimedia Booklet Page 11 Exercise 2

Monitors Monitors are always know as Visual Display Units. The VDU is the screen used to display the output from the computer The image is made up of pixels, the more pixels the better the resolution

Types of Monitors There are 2 types of monitor Cathode Ray Tube: this is the most common for a desk top computer. The screen is hard to the touch, and makes the monitor heavy. Liquid Crystal Display: This is a flat and lightweight monitor which needs very little power to operate. Usually found in laptops.

Speakers Loudspeakers are required to output sound for a multimedia presentation. Most computers have in-build loudspeakers.

Sound Cards Sound cards are additional pieces of hardware inside a computer and a good quality sound card improves the quality. Sound must be converted from its original analogue state to digital to allow the output of sound from a computer.

Digital Data Projectors These simply project a presentation from the computer onto a large white screen usually mounted against a wall

Graphics Card The quality of image displayed on a monitor depends on the quality of the graphics card installed inside the computer. The better the graphics card the better the image displayed. Graphics cards have a large amount of memory which allows a variety of resolutions

Written Task Multimedia Booklet Page 14 Exercise 3

Backing Storage Hard Disk Floppy Disk Compact Disks USB – Flash Drive

Hard Disk On a computer system the hard dist is the main backing storage devise, and usually has a storage capacity between 20 and 30 gigabytes. This large storage capacity is ideal for multimedia presentations

Floppy Disk Ideal for storing and transferring small files, (New computers don’t always have an internal floppy disk drive)

Compact Disks CD’s are know as optical storage which means that they use lasers to store and read data CD’s are portable and have direct access

CD-ROM Compact Disk Read Only Memory, have around 700 megabytes storage capacity, making them ideal for storage.

CD-R Compact Disk Recordable, information can be saved to these disks only once.

CD-RW Compact Disk Re-Writable, can be saved to as many times as you wish.

DVD/DVD-R/DVD-RW Digital Versatile Disk, the main difference between a CD and DVD is that a DVD has up to 17 gigabytes of storage.

USB Flash Drive A flash drive is a small compact memory chop that plugs into the USB port of a computer. A flash drive allows data to be stored, erased and rewritten to many times. A flash drive is portable.

Written Task Copy table from page 17 And Page 18 Exercise 4

File Types There are many different ways to store files but choosing the correct file type can dramatically reduce the amount of backing storage required. Some file types compress the data, which makes the storage requirements smaller and therefore faster to download.

Text Files Text files may have one of the following extensions .txt - text .doc – document .rtf – rich text format

Graphics Graphics files may have one of the following extension .bmp - bitmap .gig - graphics interchange format .jpeg - Joint Photographic Experts Group

Bitmapped Graphics A bitmapped graphic is a realistic picture made up of a grid of dots called pixels A pixel can be stored in 1 bit of the computers memory A black pixel is stored as a 1 and a white pixel is stored as a 0 It needs a large storage requirement to store pixels

File Compression To reduce the storage requirements of a graphic file we need to make the files smaller. We do this by compressing them.gif and.jpeg are compressed bitmap files

Moving Images Moving images come in two formats, video or animation images Videos will have one of the following file extension when you save it .mpeg - moving picture experts group .avi - audio video interleave.

Capturing and Storing Audio Sound files may have the file extensions .wav - WAV sound file .mp3 - MPEG -1 Audio Layer – 3 This is how you store information onto your MP3 player

Copyright Remember when you wish to use a picture or a song from your favorite book or CD you have to remember Copyright or you are breaking the law. Some graphics and audio file are copyright free – clipart and more and more artist and allowing you to download your songs free

Written Task Copy and complete table from page 23

Computer Task Exercise 6 Page 27 and 28

Still Images A still image is a picture that does not move They are created on a computer as a bitmapped graphics (done in a paint package), or vector-drawn graphics (done on a graphics package)

Creating Vector Drawn Graphics Layering of objects  Overlapping objects can be placed in front or behind, other objects

Scaling - Decreasing When an object is scaled you do not lose the quality of the original picture Decreasing Scale

Scaling - Increasing

Rotating When a vector – drawn graphic is rotated, it will be turned a number of degrees Rotated 90 degrees

Flipping Flip horizontally