Diapositiva 1

OrcaA screen reader sailing into uncharted waters

FOSDEM 2011

Alejandro Leiva

Screen readers 101

Screen Readers

Present screen contentsTo users who are blind or visually impaired

As they navigate using the application's commands

In speech and refreshable braille

Provide commands for more efficient accessReview chat messages

Element navigation

Font/Formatting information

Screen find, etc...

Old days: Screen Scraping

Attempt to implement a imaginator

Employ tricks

At best: somewhat unreliable

At worst: unusuable

BUT no dependence upon applications and toolkits doing the RightThing

Today: Accessibility APIs

No scraping or tricks

Direct communication with applications/toolkits

At best: very reliable

At worst: noticeably slower

BUT depends 100% upon applications and toolkits doing the RightThing

Welcome to Orca

What is Orca

It is a mammal and not a fish

It is a screen reader for AT-SPI/Atk-ready desktops

It is an open-source project under the GNOME umbrella

It is a project with an impressive user base

A brief history of Orca

Started in 2004 by Sun Microsystems

Official screen reader of GNOME in 2007

Always community-focused

Now community-run

Orca from 10000 feet

Presents screen content in speech and braille

Tracks the caret and focus via AT-SPI events

Provides a way to spatially review screen contents

Provides customized and customizable handling through applications and toolkits scripts

Orca has other duties as assigned

Compensate, often heuristically, for issues in:Application and/or toolkit implementations of Atk

User interfaces which are not 100% accessible

Provide magnification support

Provide support for users with learning disabilities

Provide access to other desktop environments

Lessons Learned

ATs often are unfunded mandates.

It is hard to keep up with external changes.

We cannot be a one size fits all solution.

Contributing to Orca needs to be easier.

What We're Planning To Do About It

We have a plan!

(Make Orca truly extensible and more performant)

Architectural Refactoring

Increased modularityCreating managers and backends

Moving features from scripts to plugins

Performance analysis and improvement

Co-existing with other ATs; not driving them

Plugin System: Presenters

Speech (for users who are blind)

Speech (for users with learning disabilities)

Braille

Magnification

Highlighting

Stuff we haven't thought of

Plugin System: Commands

Present Day and Time

Review Notifications

Caret Navigation

Structural Navigation jump amongst objects

Structural Navigation list of objects

Chat Support

Live Region Support

Skim Reading

Plugin System: Additional Tools

Script ExtendersHistory List

Structural Navigation Core Code

New scripting/plugin languageAbstraction layer

Application and toolkit idiosyncrasies

Reduced (eliminated?) need to know AT-SPI

GUI Manager

Orca can exist in gtk2/pygtk and gtk3/pygi worlds

Orca can look native in other environments:KDE

GNOME shell

Plugins need a GUI framework:To prompt users for input

To provide configuration tools

Shifting the Team Focus

Application and toolkit scripts

Plugin language

GUI and settings backends

Documentation

Growing the (plugin) developer community:Users

University programs

GSoC

End Result (We Hope)

More contributors

More functionality for Orca users

More accessible desktop environments

Way for other applications to become AT tools

This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

Avenida de la Innovacin 3 C.P. 41020 SEVILLA Tel. 954 51 75 77 951 21 04 00 Fax. 954 51 64 73 www.emergya.es

Thanks for your attention!Questions?

More information and free beerAlejandro Leiva // @gloob

www.emergya.es

Avenida de la Innovacin 3 C.P. 41020 SEVILLA Tel. 954 51 75 77 951 21 04 00 Fax. 954 51 64 73 www.emergya.es

FOSDEM 2011