CSE 615: Advanced Topics in Virtual Reality

2005 Fall

Homework 2: Experimental Exercise: Image based Modeling

The grand purpose of the exercise is to build a simple textured 3D mesh of a small object using photogrammatic technique.

Take pictures from around of a “small” object from known viewing angles as shown in the figure. Make sure the object is relatively small so that the pictures can cover the whole object (say 4~8 at 0 degrees, 45, 90, 135, …). Other camera parameters can be assumed (e.g. f, no skew, translation up to scale with arbitrary units, etc.) Use a pod to take the pictures so that less error is made.

Make a tool to manually establish corresponding points as shown. Estimate their 3D coordinates. Connect the vertices manually, and you should have a 3D mesh. Now figure out what texture to paste on each triangle. You will have to warp the part of the picture in order to do this, because what is shown on the photograph is image from certain angle. The texture on one triangle should be a warped version of this so that it is set up as if it is seen from the front direction.

You can use simpler object than a face …^^