Input

Objectives

Define input

List the characteristics of a keyboard

Describe different mouse typesand how they work

Summarize how various pointing devices work

Explain how voice recognition works

Describe various input devicesfor PDAs, smart phones, and Tablet

PCs

Explain how a digital camera works

Describe uses of PC video cameras,Web cams, and video conferencing

Discuss various scanners and reading devices and how they work

Explain the types of terminals

Summarize the various biometric devices

Identify alternative input devices for physically challenged users

What Is Input?

Input is data and instructions…

An input device is any hardware component that allows users to enter data and instructions

• Data – includes unprocessed text, numbers, images, audio, and video, and…

• Instructions – include programs, commands & user responses

The Keyboard

The keyboard has…• A typing area• A numeric keypad• Function keys (special keys that issue commands)

Alternative forms of commands:• Many programs

allow you to use key combinations, menus, or buttons to obtain the same results

The Keyboard

The insertion point is…• The blinking vertical bar that indicates where

the next character you type will display• The pointer changes

location and shape as you move the mouse or other pointing device

The Keyboard and Mouse

A cordless keyboard and mouse…• Communicate with a

receiver attached to a port on the system unit

• Use infra-red (IrDA) or radio frequency (RF) technology

Pointing Devices

A mouse is…• A pointing device that fits under the palm of your

hando controls movement of the mouse pointer on the screen

A mechanical mouse• has a rubber or metal

ball on the underside

mouse buttonswheel button

ball

An optical mouse…• Has no mechanical parts• Uses light to detect

movement• Is more precise • Can connect via cable,

or wirelessly

Other Pointing Devices

A trackball is…• A stationary pointing device with a

ball on its top or side

A touchpad is…• A touchpad is a small, flat, rectangular

pointing device sensitive to pressure and motion

• A pointing stick is pointing device shaped like pencil eraser positioned between keys on a keyboard

A pointing stick is…

Other Pointing Devices

Joystick and wheel…• Joystick is vertical lever

mounted on a base• Wheel is steering-wheel-

type input deviceo Pedal simulates car

brakes and accelerator

A light pen is…• A handheld input device that can

detect lighto Press light pen against screen

surface and then press button on pen

Other Pointing Devices

A touch screen…• Works by touching areas

of the screen with your finger• Often used in kiosks

The stylus and digital pen…• Look like ballpoint pens,

but use pressure to write text and draw lines on the screen• Used with graphics tablets (i.e. flat electronic boards)

Voice Input

How does voice recognition work?Step 2. An analog-to-digital converter (ADC) translates sound waves into digital measurements computer can process. Measurements include pitch, volume, silences, and phonemes. Phonemes are sound units such as aw and guh.

10010111010110101100001101

Step 3. Software compares spoken measurements with those in its database to find a match or list of possible matches.

Matches

Step 4. To narrow a list down, software presents user with a list of choices or uses a natural language component to predict most likely match. User may correct any selection made by software.

Natural Language Engine

Step 1. A user dictates text into a microphone.

Voice Input

MIDI (Musical Instrument Digital Interface)?

• External device, such as electronic piano keyboard, to input music and sound effects

PDAs, Tablet PCs, and Smart Phones

How is a data entered into a PDA?

PDAs, Tablet PCs, and Smart Phones

A Portable Keyboard is…

• a full-sized keyboard you can conveniently attach to a PDA as required

A Docking Station is…• an external device that a

mobile computer can be attached to that allows other peripheral devices to be connected

PDAs, Tablet PCs, and Smart Phones

A Smart Phone…• Allows users to input and

send text messages, graphics, pictures, video clips, and sound files

• Many have a built-in or attachable camera

PDAs, Tablet PCs, and Smart Phones

A Tablet PC…• Is a mobile computer that

includes handwriting recognition software

• Its primary input device is a pressure-sensitive digital pen

Digital Cameras

A Digital Camera…• Allows you to take

digital pictures• Images are viewable

immediately on the camera’s LCD screeno Download to computero Post pictures to Webo Email to friends

Digital Cameras

How does a Digital Camera work? Step 1. Point to the image to photograph and take picture. Light passes into the lens of the camera.

Step 2. Image is focused on a chip called a charge-coupled device (CCD).

Step 3. CCD generates an analog signal that represents the image.

Step 4. Analog signal is converted to digital signal by analog-to-digital converter (ADC).Step 5. Digital signal processor (DSP) adjusts quality of image and usually stores digital image on miniature mobile storage media in the camera.

Step 6. Images are transferred to a computer’s hard disk by plugging one end of the cable into a camera and the other end into a computer; or images are copied to hard disk from storage media used in the camera.

Step 7. Using software supplied with the camera, images are viewed on screen, incorporated into documents, edited, and printed.

Digital Cameras

Image resolution relates to… • The sharpness and clarity of an image• The higher the resolution, the better the image

quality, but the more expensive the camera• Pixel (picture element)

is a single point in anelectronic imageo Greater the number of

pixels, the better the image quality

Video Input

Video input is…

• The process of entering full-motion images into a computer

• A video capture card is an adapter card that converts analog video signal into digital signal that computers can use

• A Digital Video (DV) camera records video as digital signals

Video Input

PC Video Camera and Web Cams:• PC Video Camera—cDV camera used to capture

video and still images, and to make video telephone calls on the Interneto Also called a PC Camera

• Web Camc—ca video camera whose output displays on a Web page

Video Input

Video Conferencing is where…

o Whiteboard is another window on screen that can display notes and drawings simultaneously on all participants’ screens

• Two or more geographically separated people use a network or the Internet to transmit and share audio and video data

Scanners and Reading Devices

A scanner is…• A light-sensing device that

reads printed text and graphicso Used for image processing,

converting paper documents into electronic images

Drum

Flatbed

Pen or Handheld

Sheet-fed

Scanners and Reading Devices

How does a Flatbed Scanner work?

Step 2. Bright light moves underneath

scanned document.Step 3. Image of the document is reflected into a series of mirrors.

Step 1. Document to be scanned is placed face down on the glass window.

Step 6. Users can print image, e-mail it, include it in a document, or place it on a Web page.

Step 4. Light is converted to analog electrical current that is converted to digital signal by an analog-to-digital converter (ADC).

Step 5. Digital information is sent to memory in the computer to be used by illustration, desktop publishing, or other software; or it is stored on disk.

Scanners and Reading Devices

What is an Optical Reader?

o Optical Character Recognition (OCR) reads characters in OCR font

o Optical mark recognition (OMR) reads hand-drawn pencil marks, such as small circles

• Device that uses light source to read characters, marks, and codes and then converts them into digital data

Scanners and Reading Devices

A Turnaround Document is… • A document that you

return to the company that sent ito Portion you return has

information printed in OCR characters

Scanners and Reading Devices

A Bar Code Reader…• Uses laser beams to read bar codes

Scanners and Reading Devices

A bar code…• Identification code that consists of a set of

vertical lines and spaces of different widths• Universal Product

Code (UPC)

Other Input Devices

An RFID Reader…• Reads information on the

RFID tag via radio waveso Can be a handheld device

or mounted in a stationary position

RFID (Radio Frequency ID)

Other Input Devices

A Magnetic Stripe Card Reader… • Reads the magnetic

stripe on the back of a credit card

• Exposure to a magnetic field can erase the contents of a card’s magnetic stripe

Magnetic-Ink Character Recognition (MICR) Reader:

Scanners and Reading Devices

• Can read text printed with magnetised ink• Banking industry almost exclusively uses

MICR for cheque processing

Scanners and Reading Devices

A data collection device…• Obtains data directly at the location where

a transaction or event takes place• Transmits data over a network

or the Internet

Terminals

A Point Of Sale (POS) Terminal…• Records purchases,

processes credit or debit cards, and updates inventoryo Swipe credit or debit

card through a card reader

o Reads customer’s personal data from the magnetic strip

Terminals

What is an Automated Teller Machine (ATM)?• Self-service banking

machine that connects to a host computer through a network

Biometric Input

Biometrics…• Can authenticate a person’s

identity by verifying uniquepersonal characteristico Fingerprint Scanner captures

curves and indentations of a persons fingerprint

o Hand geometry system measures shape and size of person’s hand

o Eye Scanners determine unique characteristics of an individuals iris.

Biometric Input

What are examples of biometric technology?• Voice verification system compares live

speech with stored voice pattern

• Signature verification system recognizes

shape of signature• Iris recognition system reads patterns in blood vessels in back of eyeo Biometric data is sometimes

stored on smart card, which stores personal data on microprocessor embedded in card

Input Devices for Physically Challenged Users

What input devices are available for those with physical limitations?• Keyguard allows users to rest

hands on keyboard without accidentally pressing keys

• Head-mounted pointer controls pointer on screen

• New developments include gesture recognition and computerized implant devices

Summary of Input

Keyboard, mouse, and otherpointing devices

Voice input

Input devices for PDAs, smart phones, and Tablet PCs

Digital cameras

Video Input

Scanners and reading devices

Terminals

Biometric input

Input devices for physicallychallenged users