Depth Measurement


With the structure light of project, we get the information of xp (the x coordinate position of object in the projector image plane), and the camera image provides the object's pixel coordinates xc, yc. According to the result of calibration, the position Xc,Yc and Xp of object in real camera and projector frames can be computed from xp,xc and yc. So far, we can use following equation to get depth information ZC,ZP:

[(R[Xc,Yc,1]')(1,3), -[Xp,1]]*[ZC,ZP]'=-T(1,3)

Where R and T are the rigid motion transformations from camera frame to projector frame.
One image of the setup:

After we setup all the equipments, we need to estimate the intrinsic parameters of the camera and projector as well as their rigid motion transformation {R,T}, so that we can carry on above calculations of depth. This procedure is called calibration .
In our projects, we take 6 views of a teapot. Following are original pictures and 3D clouds of points obtained from depth reconstruction:
View 1:
View 2:
View 3:
View 4:
View 5:
View 6: