Major update ; QT program available on GH

A project log for 3D(ollar) Scanner

A cheap, yet surprisingly good rendition of a 3D scanner

Joshua ConwayJoshua Conway 08/05/2014 at 10:510 Comments

I messed with Java in displaying Webcam images to do the ful stack with OpenCV. Unfortunately, messing with java is all that I got accomplished, considering there is no unified simple way of opening webcams on Java. I tried JMF, FMJ, Marvin, CIVIL, webcam-capture, and other libraries. The worst crashed my java interpreter. The best displayed any webcam source at 640x480 (argh!).

So, I decided to see how hard displaying cam data would be with QT and C++... It took me 20 minutes to display an arbitrary resolution! So I decided to implement the GUI and controls in QT, OpenCV, and eventually PCL. 

On August 4th (yesterday), I made my first major checkin on Github with my new QT program. It has the config screen and video viewing screens. Now, my next big adventure is to work on calibration routines. Then, and only until they are done, will I get to scanning.

My calibration routines are simple in idea. 

1. First, calibrate the cameras for lens abberation. That is easily solved by calling in the camera calibration routine. I do this for each camera. 

2. I determine the center coordinate for the platter. That point (on each picture) is what I consider Origin. That point shouldnt change, so it's the same for each image. I use a hough circle transform, with inspiration from here:

3. I determine the slope of the laser line on the platter. This angle is the combined angular displacement between horizontal and vertical allignment. I use a hough line transform to get the position of this line, and then calculate angle versus vertical.

As long as I calculate for each camera its own calibration data, I can combine those pointclouds easily. I will need a calibration function for the second laser line and its position. I'm still thinking how I want to implement it, as my goal here is simplicity in use.