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EVT Camera Calibration#

Authors: Holoscan Team (NVIDIA)
Supported platforms: aarch64
Language: Python
Last modified: May 13, 2025
Latest version: 1.0
Minimum Holoscan SDK version: 2.1.0
Tested Holoscan SDK versions: 2.2.0
Contribution metric: Level 1 - Highly Reliable

Overview#

This application performs monitor registration using an Emergent Vision Technologies (EVT) camera. It detects April tags placed at the four corners of a monitor to establish the monitor's position and orientation in 3D space.

Hardware Requirements#

  • EVT HB-9000-G 25GE camera
  • Monitor with April tags at all four corners
  • Proper lighting conditions (well-lit environment without backlight)

Setup Instructions#

  1. Follow the Holoscan SDK user guide to set up the EVT camera
  2. Place the calibration image with April tags on the monitor
  3. Position the camera so it can see all four corners of the monitor
  4. Verify camera visibility using the high_speed_endoscopy app

Running the Application#

./run build evt_cam_calibration
sudo ./run launch evt_cam_calibration

Output#

The application generates a calibration file evt-cali.npy in the build directory, which contains the monitor's corner coordinates.

Notes#

  • The camera must have a clear view of all four April tags
  • Avoid backlighting or glare on the monitor
  • If using a different camera model, update the camera settings in the Python app or YAML configuration file
  • The application requires sudo privileges to run