cv_face_detection

Overview

The cv_face_detection application uses a selected camera to scan for faces for 10 seconds. If one or more faces are detected, it takes a snapshot, displays it on the robot’s chest screen, and logs the number of faces detected. If no faces are detected, it logs “No face detected” in the console.

Inputs

  • Optional command-line argument for selecting a camera (-c or –camera).

  • User input via terminal menu when no camera argument is provided.

Outputs

  • Log messages indicating the detection status.

  • A snapshot is captured and published to the robot’s chest display when a face is detected.

Execution

The application can be executed using:

  1. Specify the camera directly using an argument:

    python3 cv_face_detection/ --auto-run -c <camera_name>

    python3 cv_face_detection/ --auto-run --camera <camera_name>

  2. Select the camera via an interactive terminal menu:

    If no camera argument is provided, the user will be prompted to select a camera from a menu:

    python3 cv_face_detection/ --auto-run

    • If the terminal window is too small, a notification will appear instructing the user to resize it.

    • The user selects a camera by pressing the Enter key.

Behavior

  • The application enables the YunetFace model.

  • It subscribes to the detections topic for 10 seconds.

  • If no faces are detected, the following log message is displayed:

[INFO] [timestamp] [pyraya.cv_face_detection]: No face detected
  • If one or more faces are detected:

    • A snapshot is taken and displayed on the chest screen.

    • A console log message is generated:

      If one face is detected:

      [INFO] [timestamp] [pyraya.cv_face_detection]: 1 face detected 👤

      If multiple faces are detected:

      [INFO] [timestamp] [pyraya.cv_face_detection]: <number> faces detected 👥

Example Output

During execution, the output logs follow this pattern:

[INFO] [timestamp] [pyraya.cv_face_detection]: Auto running the app
[WARNING] [timestamp] [pyraya.cv_face_detection]: Enabling Yunet Face model 👁️
[WARNING] [timestamp] [pyraya.cv_face_detection]: Subscribing to _gary_cv_detector_face_detections_1 topic 🦻
[WARNING] [timestamp] [pyraya.cv_face_detection]: Detecting faces...
[INFO] [timestamp] [pyraya.cv_face_detection]: 1 face detected 👤

Additionally, in case of a detection, an output image will be displayed on the chest.

Key Notes

  • If no faces are detected within 10 seconds, a log message is shown and nothing is published on the chest display.

  • If the camera or the chest display is unavailable, the application prints an error message and exits.