DRR(1)								    Plastimatch 							    DRR(1)

NAME

       drr - create a digitally reconstructed radiograph

SYNOPSIS

       drr [options] [infile]

DESCRIPTION

       A  digitally  reconstructed  radiograph (DRR) is a synthetic radiograph which can be generated from a computed tomography (CT) scan.  It is
       used as a reference image for verifying the correct setup position of a patient prior to radiation treatment.

DRR USAGE

       The drr program that comes with plastimatch takes a CT image as input, and generates one or more output images.	The input image is in  MHA
       format, and the output images can be either pgm, pfm, or raw format.  The command line usage is:

       Usage: drr [options] [infile]
       Options:
	-A hardware	  Either "cpu" or "brook" or "cuda" (default=cpu)
	-a num		  Generate num equally spaced angles
	-N ang		  Difference between neighboring angles (in degrees)
	-nrm "x y z"	  Set the normal vector for the panel
	-vup "x y z"	  Set the vup vector (toward top row) for the panel
	-g "sad sid"	  Set the sad, sid (in mm)
	-r "r c"	  Set output resolution (in pixels)
	-s scale	  Scale the intensity of the output file
	-e		  Do exponential mapping of output values
	-c "r c"	  Set the image center (in pixels)
	-z "s1 s2"	  Set the physical size of imager (in mm)
	-w "r1 r2 c1 c2"  Only produce image for pixes in window (in pix)
	-t outformat	  Select output format: pgm, pfm or raw
	-i algorithm	  Choose algorithm {exact,uniform}
	-o "o1 o2 o3"	  Set isocenter position
	-I infile	  Set the input file in mha format
	-O outprefix	  Generate output files using the specified prefix

       The drr program can be used in either single image mode or rotational mode.  In single image mode, you specify the complete geometry of the
       x-ray source and imaging panel for a single image.  In rotational mode, the imaging geometry is assumed to be

       The command line options are described in more details as follows.

       -A hardware

	      Choose the threading mode, which is either "cpu" or "cuda".  The default value is "cpu".

	      When using CPU hardware, DRR generation uses OpenMP for multicore acceleration if your compiler supports this.   Gcc  and  Microsoft
	      Visual Studio Professional compilers support OpenMP, but Microsoft Visual Studio Express does not.

	      At the current time, cuda acceleration is not working.

       -a num

	      Generate num equally spaced angles

       -r "r1 r2"

	      Set the resolution of the imaging panel (in pixels).  Here, r1 refers to the number of rows, and r2 refers to the number of columns.

SINGLE IMAGE MODE

       The following example illustrates the use of single image mode:

       drr -nrm "1 0 0" 
	   -vup "0 0 1" 
	   -g "1000 1500" 
	   -r "1024 768" 
	   -z "400 300" 
	   -c "383.5 511.5" 
	   -o "0 -20 -50" 
	   input_file.mha

       In  the above example, the isocenter is chosen to be (0, -20, -50), the location marked on the CT image.  The orientation of the projection
       image is controlled by the nrm and vup options.	Using the default values of (1, 0, 0) and (0, 0, 1) yields the DRR  shown  on  the  right:
       [image] [image]

       By changing the normal direction (nrm), we can choose different beam direction within an isocentric orbit.  For example, an anterior-poste-
       rior (AP) DRR is generated with a normal of (0, -1, 0) as shown below: [image]

       The rotation of the imaging panel is selected using the vup option.  The default value of vup is (0, 0, 1), which means that the top of the
       panel  is  oriented toward the positive z direction in world coordinates.  If we wanted to rotate the panel by 45 degrees counter-clockwise
       on our AP view, we would set vup to the (1, 0, 1) direction, as shown in the image below.  Note that vup doesn't  have  to  be  normalized.
       [image]

ROTATIONAL MODE

       In  rotional  mode, multiple images are created.  The source and imaging panel are assumed to rotate in a circular orbit around the isocen-
       ter.  The circular orbit is performed around the Z axis, and the images are generated every -N ang degrees of the orbit.   This	is  illus-
       trated using the following example:

       drr -N 20 
	   -a 18 
	   -g "1000 1500" 
	   -r "1024 768" 
	   -z "400 300" 
	   -o "0 -20 -50" 
	   input_file.mha

       In the above example, 18 images are generated at a 20 degree interval, as follows: [image]

AUTHOR

       Plastimatch  is	a  collaborative  project.  For more documentation, please visit http://plastimatch.org.  For questions, comments, and bug
       reports, please visit http://groups.google.com/group/plastimatch.

COPYRIGHT

       Plastimatch development team (C) 2010-2011.  You are free to use, modify, and distribute plastimatch  according	to  a  BSD-style  license.
       Please see LICENSE.TXT for details.

Plastimatch 1.5 						   June 11, 2011							    DRR(1)