Screen reader
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}A screen reader is a software application that attempts to identify and interpret what is being displayed on the screen (or, more accurately, sent to standard output, whether a video monitor is present or not). This interpretation is then re-presented to the user with text-to-speech
, sound icons, or a Braille output device]. Screen readers are a form of assistive technology (AT) potentially useful to people who are blind, visually impaired (such as color blind), illiterate or learning disabled, often in combination with other AT, such as screen magnifiers.
A person's choice of screen reader is dictated by many factors, including platform, cost (even to upgrade a screen reader can cost hundreds of U.S. dollars), and the role of organizations like charities, schools, and employers. Screen reader choice is contentious: differing priorities and strong preferences are common.
Software options
See the list from the American Foundation for the Blind.
Open sources
There are also popular free and open source screen readers, such as the
- Orca (assistive technology)
for Unix-like systems and - NonVisual Desktop Access for Windows - https://www.nvaccess.org/about-nvda/
Commercial products
The most widely used screen readers[1] are separate commercial products in the English-speaking market:
- Job Access With Speech (JAWS) from Freedom Scientific
- Window-Eyes from GW Micro
- Dolphin Supernova by Dolphin Computer Access
- System Access from Serotek and
- ZoomText Magnifier/Reader from AiSquared
- Fusion - ZoomText® , with its screen magnification and visual enhancements for screen viewing ease, coupled with the power and speed of JAWS® for screen reading functionality
Operating system tools
- Microsoft Windows operating systems have included the Microsoft Narrator light-duty screen reader since Windows 2000.
- Apple Inc. Mac OS X includes VoiceOver, a feature-rich screen reader.
- The console-based Oralux Linux distribution ships with three console screen-reading environments:
- Emacspeak
- Yasr
- Speakup
Features
Screen readers speak letters, words, numbers, punctuation, and elements aloud, sending the voice output to your computer speakers or connected headphones. Screen readers are the default computer access method for people who are unable to see the computer screen. Even users with partial sight will want to learn about, and most likely use, screen readers. Perhaps right now you can operate a computer perfectly fine with just a bit of screen magnification, but what if your vision deteriorates? Even if your functional vision remains steady, pairing a screen reader with a screen magnifier will enable you to spend more time using your computer with minimal eye strain.
Screen readers use one of a growing number of computer voices, also called text-to-speech engines, to speak text. You’ve probably already heard these voices in use on phone trees and the US Weather Bureau forecast cable weather channel, and in airport gate announcements and TV commercials featuring the Apple Siri voice. The voices are usually customizable, giving you the ability to set volume, pitch, tone, and speed. You can start out with a slow voice, then, as you grow accustomed to the program, speed it up to the point where you may be able to read text faster than a computer user with sight.
Of course a screen reader must do a lot more than simply read the computer screen. As you enter data, click links, or issue other commands, the computer screen changes. If you had to wait for the software to read the full screen each and every time a single letter or graphic changed, you would never get much done. That’s the "special sauce" in these software programs: screen readers use a bit of artificial intelligence to determine what information you may wish to hear at any given time. Full-feature screen readers include dozens of screen reader keyboard shortcuts that will read highlighted text, characters, words, paragraphs, and any number of other text elements. Screen readers can announce each keystroke as you press it, decode and describe icons, and even describe certain graphic images. Screen readers also include special mouse navigation keys that allow you to manipulate the mouse pointer, moving it wherever on the screen you like, and to press other keys to perform a mouse click or double click.
If you are learning to read and write braille, most screen readers offer an additional useful option. Instead of having your screen read out loud, you can obtain a refreshable braille display and use your screen reader without audible speech.