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Camera and Projector Calibration for Projection Mapping

In this post I'd like to share my experiments in calibrating a projector using a camera with known intrinsic and extrinsic parameters. No math, just concepts. The final result is a projected image that follows a marker's position and orientation, and adjusts the image. The calibration process enables us to automatically setup the relationship between the projector and the camera that detects the marker.

In short, these are the steps performed

  1. Calibrate camera and projector relative position and orientation
  2. Detect the marker using the camera
  3. Adjust the image position and orientation based on the marker position and orientation



Experiment setup

The following videos show the results of the experiments.




 

As you can see, the projected dots follow the position and orientation of the chessboard marker. This setup will be very useful for projection mapping installations. Of course, at the current setup it will be useful only on small sizes but by using a larger marker we can theoretically use this in larger projection mapping installations.


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