What does a scanner do?

Date: 2015-10-07; view: 529.

UNIT 8 CAPTURE YOUR FAVOURITE IMAGE

Exercise 1.The eyes of your computer.

You can capture your favourite pictures using three different input devices: a scanner, a digital camera, or a camcorder.

Use the information below to answer these questions.

1. Which device is used to input text and graphic images from a printed page?

2. How does a colour scanner work?

3. Do digital cameras use film? How do they store photographs?

4. Which device would you use to take digital video?

5. What kind of software is used to manipulate video clips on the computer?

6. What do you think are the benefits of using scanners and cameras at home and in business?

A scanner 'sees' images and converts the printed text or pictures into electronic codes that can be understood by the computer.

With a flatbed scanner, the paper with the image is placed face down on a glass screen similar to a photocopier. Beneath the glass are the lighting and measurement devices. Once the scanner is activated, it reads the image as a series of dots and then generates the digitized image that is sent to the computer and stored as a file.

A colour scanner operates by using three rotating lamps, each of which has a different coloured filter: red, green and blue. The resulting three separate images are combined into one by appropriate software.

What does a digital camera do?

A digital camera takes photos electronically and converts them into digital data (binary codes made up of 1s and Os). It doesn't use the film found in a normal camera; instead it has a special light-sensitive silicon chip. Photographs are stored in the camera's memory before being sent to the computer. Some cameras can be also connected to a printer or a TVset/ to make viewing images easier.