Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Calibration of an Interactive Whiteboard

  1. Mar 21, 2010 #1
    I am trying to create an interactive whiteboard with an IR camera (wiimote actually), IR pen, and an arbitrary surface. For simplicity I'll assume the surface is a screen. To know how an IR dot from the camera's point of view relates to a point on the screen's surface, I must calibrate it with a series of points.

    I have a matrix [A] that represents the location of a series of points on the screen's surface S and a matrix that represents the location of those points as projected on to the camera's viewing plane C. From those points I am trying to figure out the transformation that must be applied to all subsequent points. If S is thought of as a plane in an ideal position relative to the camera (i.e. z=1, Sx,y=Cx,y), I know the situation can almost be modeled by:

    where [T] is a 3D transformation matrix, [P] is a 2D-3D projection matrix, [A] is a set of three 3D vectors, and is a set of three 2D vectors. If that was correct, I could simply perform -1[A] to obtain the transformation/projection matrix for subsequent points. Unfortunately, I don't know the Z of the points in and don't know how to compensate. Also, I want to use more than three calibration points, but that would make non-square.

    I have found many different materials on the topic, but none of them where exactly what I am looking for. Any help would be greatly appreciated. This problem is driving me nuts.
    Last edited: Mar 22, 2010
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted