CIT 1100

Advanced I/O Devices

In this chapter, you will learn how to:◦Explain visual capture devices◦Describe audio devices, both input and output

◦Explore game controllers◦Explain television tuners

Advanced Input/Output Devices

Scanners Used to make digital copies of existing

photos, documents, drawings, and more. Better scanners have the option of

copying directly from a photographic negative or slide

In this section, you'll look at how scanners work and what you need to know to select the correct scanner

Visual Capture Devices

All flatbed scanners work the same way, a photo or object placed face down on the glass, close the lid, then software initiates the scan. The scanner runs a bright light along the length of the glass tray once or more to capture the image A moving scanning arm contains sensors. Glass,

mirrors, and electronics, work to convert the light into signals sent to the computer

Nearly every manufacturer has some sort of drivers and other software to create an interface between your computer and the scanner

How Scanners Work

Image-editing software can be used to capture the scanners output allowing modifications to the original object The most commonly used software for

capturing output into an application is TWAIN TWAIN stands for Technology Without an

Interesting Name

Working with Scanners

Most scanners offer a feature called optical character recognition (OCR), a way to scan a document and have the computer turn the picture into text that you can manipulate by using a word processing program

Working with Scanners

The contents of the textbook was scanned using OCR, which was used to create the Power Point presentation used in this class

Even inexpensive scanners will scan at high resolutionAll modern scanners can do 48-bit scans for capturing enormous amounts of color information 

How to Choose a Scanner

The number of bits reflects how many variations of color can be captured, 16-bits allows 65536 variations of color from a single spot

The 48-bit number represents three16-bit sensors, one for each color: red, green, and blue (RGB)

Judging one scanner from another, boils down to three factors: Quality of the optics, sensors, and

electronics Capability of scanning transparent objects Auto-feeding capability

How to Choose a Scanner

Digital Cameras and CamcordersDigital cameras and camcorders electronically simulate older film technology Camcorders record moving pictures Modern digital cameras and camcorders

aren’t just still/motion devices they can do both

You can record a movie on a small camera, for example, or still im ages on a camcorder

Consumer grade digital cameras replace film with removable storage – Flash Memory Cards

Storage MediaDigital Film for Your Camera

Some camcorders use high-speed tape or tiny hard drives called Micro-drives

Nearly all digital cameras have the capability to plug directly into a Hi-Speed USB port

The newest method incorporate HDMI

Consider the amount of information a particular camera can cap ture when comparing features, expressed as megapixels Instead of light-sensitive film, digital cameras have

one or more CCD (charge-coupled device) sensors covered with photosensitive pixels (photosites) to capture the image

The more pixels the higher the resolution of the images

A two-megapixel camera produces snapshot-sized 4x6” picture with print photo quality, a five megapixel unit can produce photo quality 8x10 inch print

Quality

Camcorders capture video in one of two formats, High Definition (HD) or Standard Def inition (SD) HD captures will be widescreen to match HD

TV SD captures stay within the 4:3 aspect ratio to

match older style televisions and monitors HD captures higher-resolution images for the

most part, though a high-end SD camera will outperform a lower-end HD camera any day 

HD vs. SD

PC cameras, Webcams are fairly new type of advanced I/0 device Features to look for when buying webcams and some

problems you can run into using them:◦ Image quality - measured in pixels. There are webcams with

resolutions of as few as 100,000 pixels, all the way to webcams with millions of pixels which would require a huge amount of internet bandwidth

◦ Frame rate - number of times the camera scans per second, higher frame rates make for smoother video using more bandwidth, 30 frames per second is considered the best.

A good camera with a high resolution and fast frame rate will provide excellent video conferencing capa bilities

Web Cameras

Sound controllers enable the computer to play and record sound. All modern computers come with sound controllers built into the motherboardThe simplest sound controllers have three 3.5 mm audio ports, called jacks

Audio Devices

Audio Devices

Connector

Line out

Color

G reen

Purpose

Main speakers or headphones

Microphone Pink Recording sounds

Line in

Subwoofer

Blue

O range

Sound input from an audio device

Thum ping bass with a subwoofer attached

Rear surround sound Black Rear speakers

Middle surround sound G ray Extra speakers in a 7.1 sound setup

Most sound controllers have color-coded jacks for the specific connec tions:

Video games come with a host of controllers for controlling aspects of the game. You can get a joystick for controlling flight simulation games

Game Controllers

Force feedback game controllers are output devices as well as input devices, when the stick is shaking on a hard turn and resisting your efforts

Most local TV stations broadcast high definition sig nals, with the proper TV tuner, you can watch HDTV on a PC By incorporating a cable or satellite feed you

can watch television as you would with a regular TV

To install HDTV requires four components: 1. Tuner device 2. Antenna or cable connection 3. Tuning ap plication4. Program guide

TV Tuners

Tuners come in just about every expansion option available for computers: ◦ PCI ◦ PCie ◦ PC Card or Express Card ◦ Hi-Speed USB for desktop and laptop computers

TV Tuners

Tuner hardware comes with a standard coaxial connection

Once installed you need to load the specific application or appli cations If you have Windows Media Center (through

either that version of Windows XP, Windows Vista Ultimate, or Windows 7), that will often be the tool of choice

Ubuntu MYTH TV provides a complete open source Home Media application

Tuner Software