Enable Alert Mode#

Alert Mode is an optional feature in Live Video Captioning that enables alert-style visual feedback for binary classification prompts. When enabled, the application provides enhanced visual indicators for “Yes” or “No” responses, making it ideal for automated monitoring and surveillance scenarios.

Overview#

In Alert Mode, the application:

  • Changes the default prompt to: “Is there an accident in the stream? Just Answer with a Yes or No”

  • Applies distinct visual styling to “Yes” and “No” responses in the caption display

  • Updates the application title to “Live Video Captioning and Alerts”

  • Provides clear alert indicators for detections (Green vs Red)

This mode is particularly useful for:

  • Accident Detection: Monitor traffic streams for incidents

  • Security Monitoring: Detect unauthorized access or suspicious activity

  • Safety Compliance: Verify safety protocols are being followed

  • Anomaly Detection: Identify unusual events in video feeds

Enabling Alert Mode#

Option 1: Environment Variable in .env File#

Add or modify the ALERT_MODE variable in your .env file:

# .env file
WHIP_SERVER_IP=mediamtx
WHIP_SERVER_PORT=8889
WHIP_SERVER_TIMEOUT=30s
PROJECT_NAME=live-captioning
HOST_IP=<HOST_IP>
EVAM_HOST_PORT=8040
EVAM_PORT=8080
DASHBOARD_PORT=4173
WEBRTC_PEER_ID=stream
ALERT_MODE=True   # Enable Alert Mode

Visual Indicators#

When Alert Mode is enabled:

Response

Visual Style

Yes

Red/Alert highlighting indicating a positive detection

No

Green/Normal highlighting indicating no detection

Custom Prompts#

While Alert Mode sets a default accident detection prompt, you can customize the prompt in the dashboard UI to suit your specific use case. The key requirement is that your prompt should elicit a “Yes” or “No” response for proper alert styling.

Example prompts for different scenarios:

  • Fire Detection: “Is there a fire or smoke visible in the stream? Just Answer with a Yes or No”

  • Crowd Detection: “Is there a large crowd gathering? Just Answer with a Yes or No”

  • Vehicle Detection: “Is there a stopped vehicle blocking the road? Just Answer with a Yes or No”

  • PPE Compliance: “Is the person wearing a safety helmet? Just Answer with a Yes or No”

Troubleshooting#

Alert Mode Not Activating#

  1. Verify the ALERT_MODE environment variable is set correctly in your .env file

  2. Ensure Docker Compose picks up the environment variable:

    docker compose down
docker compose up

  3. Check the application title - it should display “Live Video Captioning and Alerts”

Alert Styling Not Appearing#

  • Ensure your prompt is designed to receive “Yes” or “No” responses

  • Check that the VLM model is generating clear binary responses

  • Verify the metadata stream is connected (check the status indicator)

Next Steps#