NVDA: A Free, Open Source Screen Reader for Microsoft Windows
Who are We?
- Core developers of NVDA
- From NV Access
- An Australian non-profit organisation
- Supports/develops free, open source assistive technologies
- www.nvaccess.org
So What is NVDA?
- NonVisual Desktop Access
- Free, open source screen reader for Microsoft Windows
- www.nvda-project.org
- Allows blind/vision impaired users to access Windows
- Allows user to "read the screen" via synthetic speech/Braille
Abbreviations
- NVDA: NonVisual Desktop Access
- FOSS: free and open source software
- A11y: accessibility
- GNU GPL: GNU General Public License
History
- In the beginning...
- April 2006: Concept was born
- July 2006: First public release
- Similar in functionality to Narrator
History
- July 2006: Jamie started working on NVDA
- Late 2006: First support for multiple languages
- December 2006: IAccessible2
- January 2007: Request from Mozilla accessibility to support Firefox
History
- March 2007: Mick attended CSUN 2007 (sponsored by Mozilla)
- Many people interested in the project
- After CSUN: Java Access Bridge; untying from MSAA only
- July 2007: Mozilla grant to improve support for Firefox
History
- October 2007: Mozilla Summit
- Beginnings of the grant to employ Jamie full time
- February 2008: Jamie began working on project full time
History
- Just before CSUN 2008: New Firefox 3 support
- March 2008: CSUN 2008
- Began to notice a great deal of respect from the industry
- August 2008: Info Vision 08 presentation
History
- August 2008: Handy Tech offered help with braille display support
- October 2008: Braille display support implemented
- December 2008: Microsoft grant to implement support for UIA and improve IE support
Features
- Zero cost!
- Multilingual: translated into over 20 languages
- Portability: run entirely from a USB drive
Features
- Talking installer
- Excellent support for Mozilla Firefox 3 including ARIA
- Excellent support for Mozilla Thunderbird 3
- Support for accessible Java applications
Features
- Support for Microsoft Internet explorer, Outlook Express/Windows Mail
- Support for Microsoft Word and Excel
- Support for Adobe Reader
- Support for Windows command prompt and console applications
Interesting Features
- Audible progress beeps instead of speaking percentages
- Announcement of text under the mouse
- Optional audible indication of mouse position
NV Access
- NVDA supported by NV Access
- Non-profit organisation in Melbourne, Australia
- Supports/develops FOSS that enables blind/vision impaired people to access technology
- Procures funding and provides admin/management
- Funded through donations and grants
Philosophy
- Primary mission: to lower the barrier to accessible computing
- We believe that accessibility should not be an extra cost for the user
- Free and open source software can best further this goal
Philosophy
- NVDA licensed under the GNU GPL
- Source code freely available to anyone
- Benefits both NVDA and a11y in general
- We actively participate in other FOSS development; e.g. Mozilla
- We support emerging open a11y standards/technologies; e.g. IAccessible2
Philosophy
- Marco Zehe, Mozilla Corporation Accessibility QA
- Mutually benefitial relationship between NVDA and Mozilla
Philosophy
- NVDA community is of paramount importance
- User feedback often directs the course of the project
- Fantastic opportunity for experimentation/innovation
Technical Design
- Mostly written in Python programming language
- Allows for rapid development
- In-process code written in C++
- Extensible, object oriented, abstract design
- Focus on accuracy and efficiency
Technical Design: Architecture
- API handlers: setup, teardown, event listening, etc. for specific APIs
- NVDA Objects: support for specific controls or windows
- App Modules: specific support for a particular application
- Virtual buffers: allow for display of complex documents or other data
- Core pumps API handlers, dispatches NVDA events, etc.
Work in Progress
- Table reporting and navigation on the web
- Better, faster Internet Explorer support
- Better, faster Adobe Reader support
- Support for UI Automation in Windows 7 and beyond
What's Next?
- Complete support for ARIA live regions
- Other ARIA improvements and features
- Support for rich text editing on the web
- Enhancements to braille display support
Further into the Future
- Enhanced support for office suites
- Ability to read display information