SPFToScalarMap  [--returnparameterfile <std::string>]
                   [--processinformationaddress <std::string>] [--xml]
                   [--echo] [--debug] [-p] [--md0 <double>] [--tau
                   <double>] [--nt <int>] [--mask <std::string>] [--mapType
                   <RTO|MSD|PFA>] [--mdImage <std::string>] [--scale
                   <double>] [--ra <int>] [--sh <int>] [--] [--version]
                   [-h] <std::string> <std::string>


   --returnparameterfile <std::string>
     Filename in which to write simple return parameters (int, float,
     int-vector, etc.) as opposed to bulk return parameters (image,
     geometry, transform, measurement, table).

   --processinformationaddress <std::string>
     Address of a structure to store process information (progress, abort,
     etc.). (value: 0)

     Produce xml description of command line arguments (value: 0)

     Echo the command line arguments (value: 0)

     debug (value: 0)

   -p,  --progress
     show progress of processing (value: 0)

   --md0 <double>
     Typical MD value. (value: 0.0007)

   --tau <double>
     Tau value. The default is calculated based on 4*pi*pi*tau=1. (value:

   --nt <int>
     Number of threads. If it not positive, then the default number for
     multiple threads is used. (value: -1)

   --mask <std::string>
     Mask file.

   --mapType <RTO|MSD|PFA>
     Type of scalar maps. (value: RTO)

   --mdImage <std::string>
     Mean diffusivity Image for adaptive scale.

   --scale <double>
     Scale for SPF basis. If it is negative, the default value based on
     typical MD is used. (value: -1)

   --ra <int>
     Rank for radial basis. (value: 1)

   --sh <int>
     Rank for SH basis. (value: 4)

   --,  --ignore_rest
     Ignores the rest of the labeled arguments following this flag.

     Displays version information and exits.

   -h,  --help
     Displays usage information and exits.

     (required)  Input Image File represented by SPF basis.

     (required)  Output Image File (scalar map).

   Description: Estimate scalar maps using SPFI.


   SPFToScalarMap signalSPF.nii.gz rto.nii.gz --mapType RTO  --sh 8 --ra 4
   --mdImage D_sh4_ra1.nii.gz

   SPFToScalarMap signalSPF.nii.gz msd.nii.gz --mapType MSD  --sh 8 --ra 4
   --mdImage D_sh4_ra1.nii.gz

   SPFToScalarMap signalSPF.nii.gz pfa.nii.gz --mapType PFA  --sh 8 --ra 4
   --mdImage D_sh4_ra1.nii.gz


   Jian Cheng, Aurobrata Ghosh, Rachid Deriche, Tianzi Jiang, 'Model-Free,
   Regularized, Fast, and Robust Analytical Orientation Distribution
   Function Estimation', Medical Image Computing and Computer-Assisted
   Intervention (MICCAI'10), vol. 6361, pp. 648–656, sep, 2010.

   Jian Cheng, Aurobrata Ghosh, Tianzi Jiang, Rachid Deriche, 'Model-free
   and Analytical EAP Reconstruction via Spherical Polar Fourier Diffusion
   MRI', Medical Image Computing and Computer-Assisted Intervention
   (MICCAI'10), vol. 6361, pp. 590–597, sep, 2010.

   Author(s): Jian Cheng (jian.cheng.1983@gmail.com)

   Acknowledgements: Thank you everyone.