Multilingual Screen Reader

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Multi-lingual Screen Reader
SUPERVISORS Prof. M. Balakrishnan CSE, IIT
DELHI Dipendra Manocha, Director IT Lab (NAB)

• Tejram Meena (2002120)
• Naveen Mishra(2002121)

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Outline

• Brief Design Model
• Screen Reader Accessiblity Interface
• Implementation
• Limitations
• Demonstration

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Brief Design Model
2. Sends that info to the output devices such as
speech synthesizer in text form
Windows
1. Screen reader monitors info from comp screen,
keyboard mouse
3. Speech synthesiser (TTS) converts text info to
speech.
Screen Reader
English TTS
Hindi TTS
Other TTS
Speech Synthesizers
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Screen Reader Accessibility Interfaces
Screen Reader
Accessibility Interface (MSAA)
Accessibility Interface (Win 32)
Accessibility Interface (Device Driver)
Accessibility Interface COM/Automation
Accessibility Interface
User Interface Objects Windows Scroll bars Text
Tree View Edit controls Static
controls . Buttons Labels Checkbox
RadioButton Combo box .
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Implementation

• Class Hierarchy
• Keyboard
• Handles low level keyboard commands, and then
  converts them to the commands that other objects
  understand. It manages keyboard configuration
  objects which provide for commands if the files
  exist at various levels.
• It also sends the character information to the
  synthesiser if the key typed generates typing
  characters.

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Class Hierarchy..

• KeyboardFile
• This class represents each type of
  keyboard.xml file in the system. i.e. one file
  for each type
• (A) application and language specific,
• (B) default application and language specific,
• (C) application specific and default language
  and
• (D) default language and default application.
  Default language is english.

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Class Hierarchy..

• MSAA
• Microsoft Active Accessibility (MSAA) provides a
  mechanism for application to expose information
  which is relevant for the user. MSAA class and
  WinEventproc a global function help to get
  information from MSAA system of windows.

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Class Hierarchy..

• ButtonReader GeneralReader
• ButtonReader handles keyboard commands and focus
  events when a button such as check box, radio
  button, push button gets the focus.

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Class Hierarchy..

• MenuItemReader GeneralReader
• Handles keyboard commands and focus events when
  a menu item gets the focus.
• ScrollBarReader GeneralReader
• This is to work with the scroll bars, the once
  which are displayed to move in verticle or
  horizontal direction.

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Class Hierarchy..

• ISynthesiser
• Methods
• Speak(ByVal voiceString As String, Optional
  LangID As Long 0)
• Flush()
• IncreaseRate()
• DecreaseRate()
• ChangeVoiceForward()
• ChangeVoiceBackward()
• ChangePunctuation()
• ChangeSynthesiser()

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Class Hierarchy..

• Synthesiser ISynthesiser
• safaSynthesiserObject is of type of Synthesiser
  class which is used with in the application for
  speaking text.
• ViaVoice ISynthesiser
• SAFA interface to viaVoice speech synthesiser

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Tested for..

• Reads out the information about the present
  active window (from MSAA).
• Reads all input from the keyboard
• Reads the menu button and the drop down menu

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Limitations faced

• TTS convertor does not read special characters
  such as , ( , ), ,
• No of functions implemented.

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• Thank You