DWIMultipleShellSplit  [--returnparameterfile <std::string>]
                          [--processinformationaddress <std::string>]
                          [--xml] [--echo] [-v] [--threshold <double>]
                          [--b0InEachShell] [--b0normalization] [--outb0
                          <std::string>] [--outb <std::string>] [--outgrad
                          <std::string>] [--ingrad <std::string>] [--mask
                          <std::string>] [--] [--version] [-h]
                          <std::string> <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.). (default: 0)

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

     Echo the command line arguments (default: 0)

   -v,  --
     Verbose output. (default: 0)

   --threshold <double>
     Threshold to determine b values for each shell (default: 2)

     Set b0 image into each shell. (default: 0)

     Normalization with respect to the non-diffusion-weighted reference
     image. (default: 0)

   --outb0 <std::string>
     Output (averaged) b0 image file. If no given, b0 image is put as the
     first volume of each each.

   --outb <std::string>
     Output b-Value file.

   --outgrad <std::string>
     Output Gradient file for each shell.

   --ingrad <std::string>
     Gradient file.

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

   --,  --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 DWI data file.

     (required)  b-Value file.

     (required)  Output split DWI data file for each shell.

   Description: Split mutiple shell DWI data into several single shell

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

   Acknowledgements: Thank you everyone.