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 "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-posterior (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 isocenter.  The circular orbit is performed
       around the Z axis, and the images are generated every -N ang degrees of the  orbit.   This
       is illustrated 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  additional  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) 2010-2013.  You are free to use, modify, and distribute
       plastimatch according to a BSD-style license.  Please see LICENSE.TXT for details.