BlackOut – Darkens the Screen Except for the Speech and Braille Viewer

• Author: BFW Würzburg

Purpose of the Add-on

BlackOut was developed to demonstrate to sighted people what an NVDA user perceives through speech and/or Braille.

This is especially useful for:

• Training sessions and presentations
• Raising awareness for screen reader usage
• Situations where sighted people should not be distracted

The screen is completely darkened. While the screen is black, you can continue using NVDA as usual.

What Remains Visible?

BlackOut keeps only two NVDA windows visible:

• Speech Viewer
• Braille Viewer

All other windows are fully hidden.

Usage

Turning BlackOut On and Off

Press:

• NVDA + Alt + B

This key command toggles the BlackOut mode on or off. You can change the gesture in NVDA’s Input Gestures dialog.

Behavior When Activated

When you activate BlackOut:

1. The Speech Viewer remains visible.
2. If it is not already open, the add-on opens it automatically.
3. The Braille Viewer remains visible if you had previously enabled it. You can also open it afterwards.
4. The rest of the screen becomes completely black.
5. NVDA displays the message:
   “BlackOut activated, Speech Viewer visible”

You can continue working with NVDA normally.

Only the primary display is darkened. For presentations, you can duplicate it to a projector or second screen using Windows + P.

Behavior When Deactivated

When you deactivate BlackOut:

1. The screen becomes fully visible again.
2. If the Speech Viewer was opened by the add-on, it will be closed automatically.
3. If it was already open beforehand, it remains open.
4. NVDA displays the message:
   “BlackOut deactivated”

Tips for Use

• For training:
  Ideal for showing sighted people how screen reader users work—without desktop distractions.
• For presentations:
  The focus remains entirely on NVDA’s output.
• For awareness:
  BlackOut demonstrates how little visual information NVDA users rely on.

The add-on handles everything automatically in the background:

• It detects the NVDA viewer windows on its own.
• It continuously adjusts the visible areas if you move the windows.
• It does not interfere with your work and does not take focus.

No configuration is required.

Summary

| Function | Description | |---------|-------------| | Darken screen | NVDA+Alt+B | | Visible windows | Speech Viewer, Braille Viewer | | Automatic opening | Speech Viewer is opened if needed | | Automatic closing | Speech Viewer is closed if opened by the add-on | | Use cases | Training, presentations, awareness |