CIT 1100. In this chapter, you will learn how to: ◦ Explain visual capture devices ◦ Describe...
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Transcript of CIT 1100. In this chapter, you will learn how to: ◦ Explain visual capture devices ◦ Describe...
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