Here is a list of the RTK command lines you will have to run during the training, along with the data you will need. To start, download the following CT data and a relevant Cone-Beam CT geometry file.
To forward project the CT volume, following the geometry described in geometry.xml, run
rtkforwardprojections -i muCT.mha -o projections.mha -g geometry.xml
Look at the result using vv
There are as many projections as described in the geometry.xml file. You can edit the geometry.xml file, remove all projections except one, and try again. Such a modified geometry.xml file is already provided along with the data (singleProjectionGeometry.xml). Run the following command line
rtkforwardprojections -i muCT.mha -o singleProjection.mha -g singleProjectionGeometry.xml
You can check with vv that the file contains only one projection
Start by back projecting a single projection. Run
rtkbackprojections -p . -r singleProjection.mha -o singleBackProjection.mha -g singleProjectionGeometry.xml
Observe the result with vv
As you can see, the projection data seems to be smeared into the volume. Now back project all projections, by running
rtkbackprojections -p . -r projections.mha -o backProjection.mha -g geometry.xml
Look at the result with vv. In order to compare it with the original image, run
vv backProjection.mha muCT.mha --linkall
Click in one of the display windows, hit 'Ctrl + G' to center the view on the tumor. Hit 'w' to automatically compute reasonable window and level values. You can navigate between "muCT.mha" and "backProjection.mha" by hitting the 'Tab' key.