The past several days seem to be filled with LOTS and LOTS of MATLAB. We are still trying to develop programs that will simulate objects in 3D space and then use that data in another program to create a 3D images. In the long run we are just focusing on the program that will take images of the object(s) from various angles and compile them into a 3D reconstruction. However, first we are just using simple 2D squares and now 3D spheres with known locations and dimensions to see how accurately we can approximate the real shape of it. Throughout the past few days Allan and I have been trying to create a program that will simulate 16 frames of a sphere from 16 different locations.
We both approached the program with the same idea that if you take a lot of circles or disks and stack them on top of each other you will have a sphere. However we ran into a lot of trouble with just drawing a circle. Although it seemed easy and basic for a program like MATLAB, we could not produce a circle in the correct format what we needed. After much frustration Professor Buma helped us out and sent us a code that seemed to take him no time at all. Although I think I could have gotten it eventually, my MATLAB skills are not good enough to complete it in a timely manner.
Once I could draw a circle, the rest of the code moved a little quicker. I made a code that would produce 16 frames (like the 16 frames for the boxes) for a sphere made of multiple disks on top of each other. I based this code off of the one for the boxes with a few differences due to the sphere being 3D and not 2D. Once I had the code to produce the pictures of sphere I moved on the tomosynthesis part of the exercise. I used the same code to combine the image as I did for the boxes. I did not have to change much about my tomosynthesis code which was good because that means it is fairly general and can be used for a wider range of images. After I got this code to work I started adding more spheres with different sizes and locations.
Here is an image with four (of the 16) frames of three spheres from different source locations.
Figure 1:
The next two figures are part of the tomosynthesis of the images. Similar to my previous code for the boxes my code samples different z-values and produces ‘slices’ of the 3D model of the objects. Although the pictures aren’t great you can still see in figure 2 that in the bottom right frame the two circles to the left are clearer in this image because the center of these spheres is located at z=4. The same thing goes for the third sphere in the bottom left frame of figure 3 because that is also where the center of the sphere is, thus the image is clearer.
Figure 2:
Figure 3:
