Using the stereo camera
Background material
We have a BumbleBee stereo camera from Point Grey Research. This has the very nice property that it's two cameras are already calibrated, and they are fixed together in a little box, and their stereo parameters are also callibrated. So we can get rectified images and skip striaght to the fun stuff.
It comes with an SDK that lets us develop software that uses the camera and the stereo processing software that comes with it. Here is the manual.
Read pages 115-123 to get some background on what this setup does.
FYI, the "triclops" is their 3-camera box, we just have the 2-camera one.
Here is some info on the 3D modeling functionality, from their Web site.
Getting started
The camera is in 3228 Academic Surge; I assume you all can get in. It is attached to the Dell in the common area. There is an account called cse289h, and I assume you know the password.
The demo software is Digiclops Demo II. Start it up.
- Select 640x480 for the camera resolution (it's really 1024xsomething, but the demo software can't deal with this yet; note on this).
- View->3D model toolbar
- Look at some of the 2D windows (raw/rectified/disparity, left and right).
- Bring up a 3D window (as opposed to 3D model window), which shows "live" 3D models. Take a look at your own head. How's it doing?
- To make it do better, bring up the stereo parameters window. Probably you will have to adjust the max and min disparity; you want them as close together as possible while seeing the object you want to capture in the 3D model window.
See what you can figure out about what the other functions in the stereo parameters and validation boxes do (stereo mask, edge mask, and the three kinds of validation). Write down your guesses for class on Wednesday 28.
- The 3D model capture feature uses a 25-image temporal window (somehow or other...). Try making a model of the Mayan hiroglyph plaque. Aim the camera at it, and fool with the stereo parameters.
Once they look OK,
get rid of the 3D window and get the 3D model window.
Drag the slider to select 25 frames and capture the image.
Notice stereo turns OFF in the "processing" box; this cuts the pipeline and the image is fixed. You can start it up again by turning stereo "ON".
- You can rotate, etc, in the 3D model window. How good is your model? Without color/texture map?
- The "texture window" makes a moving image to project on the object as a kind of unstructured light. Bring it up, turn on the projector, and make the Digiclops window cover both monitor images (the Dell thinks the projector image is the monitor to the RIGHT of the real monitor; believe me, this is better).
If the projector can't find a signal from the PC,
make sure the machine is configured for two monitors, with monitor 2 on the right. Control Panel->Appearance&Themes->Display.
- Try making the model again. Better? I thought not.
- For class Wednesday, print out an image (with/without texture map) of a model you made. This can just be from the windows in the demo software or displayed in some other way.
- TURN OFF THE PROJECTOR when you are done.