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1. WHAT IS A SCREEN READER FOR BLIND HOW TO
2. WHAT IS A SCREEN READER FOR BLIND MAC OS X
3. WHAT IS A SCREEN READER FOR BLIND UPGRADE
4. WHAT IS A SCREEN READER FOR BLIND SOFTWARE

For example, a screen reader can be told that the current focus is on a button and the button caption to be communicated to the user. Screen readers can query the operating system or application for what is currently being displayed and receive updates when the display changes. These involve the provision of alternative and accessible representations of what is being displayed on the screen accessed through an API. Operating system and application designers have attempted to address these problems by providing ways for screen readers to access the display contents without having to maintain an off-screen model. However, maintaining an off-screen model is a significant technical challenge: hooking the low-level messages and maintaining an accurate model are both difficult tasks.

Screen readers can also communicate information on menus, controls, and other visual constructs to permit blind users to interact with these constructs. The user can switch between controls (such as buttons) available on the screen and the captions and control contents will be read aloud and/or shown on refreshable Braille display. These messages are intercepted and used to construct the off-screen model. Screen readers were therefore forced to employ new low-level techniques, gathering messages from the operating system and using these to build up an "off-screen model", a representation of the display in which the required text content is stored.įor example, the operating system might send messages to draw a command button and its caption. A GUI has characters and graphics drawn on the screen at particular positions, and as such there is no purely textual representation of the graphical contents of the display. With the arrival of graphical user interfaces (GUIs), the situation became more complicated. Title=Access to personal computers using speech synthesis. In the 1980s, the Research Centre for the Education of the Visually Handicapped (RCEVH) at the University of Birmingham developed Screen Reader for the BBC Micro and NEC Portable. BYTE, September 1982Īccessyear=2006 ] and communicating the results to the user. All this information could therefore all be obtained from the system either by hooking the flow of information around the system and reading the screen buffer or by using a standard hardware output socket [ cite web

WHAT IS A SCREEN READER FOR BLIND HOW TO

WP and Google may be the only 2 Web apps many of them know how to use! Input was by keyboard. Clarifyme|date=September 2008|reason=Link to explanation of this stuff we cannot just throw computer geek jargon at our readers, many of whom have no technical background at all. In early operating systems, such as MS-DOS, which employed command line interfaces (CLIs), the screen display consisted of characters mapping directly to a screen buffer in memory and a cursor position. Title = Guidelines for Accessible and Usable Web Sites: Observing Users Who Work With Screen ReadersĪccessdate = ] are separate commercial products: JAWS from Freedom Scientific, Window-Eyes from GW Micro, Hal from Dolphin Computer Access, and ZoomText Magnifier/Reader from Ai Squared are prominent examples in the English-speaking market. The most widely used screen readers [ cite paperĪuthor = Theofanos, Mary Frances, and Redish, Janice (Ginny) There are also open source screen readers, such as the for GNOME and NonVisual Desktop Access for Windows. The open source GNOME desktop environment long included Gnopernicus and now includes Orca. The console-based Oralux Linux distribution ships with three screen-reading environments: Emacspeak, Yasr and Speakup.

WHAT IS A SCREEN READER FOR BLIND MAC OS X

Mac OS X includes VoiceOver, a feature-rich screen reader.

Screen reader choice is contentious: differing priorities and strong preferences are common.Īpple Inc. dollars), and the role of organizations like charities, schools, and employers.

WHAT IS A SCREEN READER FOR BLIND UPGRADE

Screen readers are a form of assistive technology (AT) potentially useful to people who are blind, visually impaired, illiterate or learning disabled, often in combination with other AT, such as screen magnifiers.Ī 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. This interpretation is then re-presented to the user with text-to-speech, sound icons, or a Braille output device.

WHAT IS A SCREEN READER FOR BLIND SOFTWARE

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).