env_math.c

Go to the documentation of this file.

/*!@file Envision/env_math.c */
 
// //////////////////////////////////////////////////////////////////// //
// The iLab Neuromorphic Vision C++ Toolkit - Copyright (C) 2000-2005   //
// by the University of Southern California (USC) and the iLab at USC.  //
// See http://iLab.usc.edu for information about this project.          //
// //////////////////////////////////////////////////////////////////// //
// Major portions of the iLab Neuromorphic Vision Toolkit are protected //
// under the U.S. patent ``Computation of Intrinsic Perceptual Saliency //
// in Visual Environments, and Applications'' by Christof Koch and      //
// Laurent Itti, California Institute of Technology, 2001 (patent       //
// pending; application number 09/912,225 filed July 23, 2001; see      //
// http://pair.uspto.gov/cgi-bin/final/home.pl for current status).     //
// //////////////////////////////////////////////////////////////////// //
// This file is part of the iLab Neuromorphic Vision C++ Toolkit.       //
//                                                                      //
// The iLab Neuromorphic Vision C++ Toolkit is free software; you can   //
// redistribute it and/or modify it under the terms of the GNU General  //
// Public License as published by the Free Software Foundation; either  //
// version 2 of the License, or (at your option) any later version.     //
//                                                                      //
// The iLab Neuromorphic Vision C++ Toolkit is distributed in the hope  //
// that it will be useful, but WITHOUT ANY WARRANTY; without even the   //
// implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      //
// PURPOSE.  See the GNU General Public License for more details.       //
//                                                                      //
// You should have received a copy of the GNU General Public License    //
// along with the iLab Neuromorphic Vision C++ Toolkit; if not, write   //
// to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,   //
// Boston, MA 02111-1307 USA.                                           //
// //////////////////////////////////////////////////////////////////// //
//
// Primary maintainer for this file: Rob Peters <rjpeters at usc dot edu>
// $HeadURL: svn://isvn.usc.edu/software/invt/trunk/saliency/src/Envision/env_math.c $
// $Id: env_math.c 15495 2014-01-23 02:32:14Z itti $
//
 
#include <jevoisbase/Components/Saliency/env_math.h>
 
#include <jevoisbase/Components/Saliency/env_c_math_ops.h>
#include <jevoisbase/Components/Saliency/env_params.h>
 
// ######################################################################
void env_init_integer_math(struct env_math* imath, const struct env_params* envp)
{
  /* Trig tables generated with this matlab code:
     
     tabsize = 256;
     tabbits = 8;
     tabtype = 'intg16';
     
     arg=(2*pi*(0:(5*tabsize/4 - 1)) / tabsize);
     sinarg=sin(arg);
     sintab=fix(sinarg * (2^tabbits));
     
     fprintf('static const %s trigtab[] =\n', tabtype);
     fprintf('  {\n');
     fprintf(['    /' '* *' '/ %4d, %4d, %4d, %4d, %4d, %4d, %4d, %4d, %4d, %4d, %4d, %4d, %4d, %4d, %4d, %4d,\n'], sintab);
     fprintf('  };\n\n');
     
  */
  
  static const intg16 trigtab[] =
    {
      /* */    0,    6,   12,   18,   25,   31,   37,   43,   49,   56,   62,   68,   74,   80,   86,   92,
      /* */   97,  103,  109,  115,  120,  126,  131,  136,  142,  147,  152,  157,  162,  167,  171,  176,
      /* */  181,  185,  189,  193,  197,  201,  205,  209,  212,  216,  219,  222,  225,  228,  231,  234,
      /* */  236,  238,  241,  243,  244,  246,  248,  249,  251,  252,  253,  254,  254,  255,  255,  255,
      /* */  256,  255,  255,  255,  254,  254,  253,  252,  251,  249,  248,  246,  244,  243,  241,  238,
      /* */  236,  234,  231,  228,  225,  222,  219,  216,  212,  209,  205,  201,  197,  193,  189,  185,
      /* */  181,  176,  171,  167,  162,  157,  152,  147,  142,  136,  131,  126,  120,  115,  109,  103,
      /* */   97,   92,   86,   80,   74,   68,   62,   56,   49,   43,   37,   31,   25,   18,   12,    6,
      /* */    0,   -6,  -12,  -18,  -25,  -31,  -37,  -43,  -49,  -56,  -62,  -68,  -74,  -80,  -86,  -92,
      /* */  -97, -103, -109, -115, -120, -126, -131, -136, -142, -147, -152, -157, -162, -167, -171, -176,
      /* */ -181, -185, -189, -193, -197, -201, -205, -209, -212, -216, -219, -222, -225, -228, -231, -234,
      /* */ -236, -238, -241, -243, -244, -246, -248, -249, -251, -252, -253, -254, -254, -255, -255, -255,
      /* */ -256, -255, -255, -255, -254, -254, -253, -252, -251, -249, -248, -246, -244, -243, -241, -238,
      /* */ -236, -234, -231, -228, -225, -222, -219, -216, -212, -209, -205, -201, -197, -193, -189, -185,
      /* */ -181, -176, -171, -167, -162, -157, -152, -147, -142, -136, -131, -126, -120, -115, -109, -103,
      /* */  -97,  -92,  -86,  -80,  -74,  -68,  -62,  -56,  -49,  -43,  -37,  -31,  -25,  -18,  -12,   -6,
      /* */    0,    6,   12,   18,   25,   31,   37,   43,   49,   56,   62,   68,   74,   80,   86,   92,
      /* */   97,  103,  109,  115,  120,  126,  131,  136,  142,  147,  152,  157,  162,  167,  171,  176,
      /* */  181,  185,  189,  193,  197,  201,  205,  209,  212,  216,  219,  222,  225,  228,  231,  234,
      /* */  236,  238,  241,  243,  244,  246,  248,  249,  251,  252,  253,  254,  254,  255,  255,  255,
    };
  
  typedef char trig_tab_size_check[ (sizeof(trigtab) / sizeof(trigtab[0]))
                                    == (5*ENV_TRIG_TABSIZ/4) ? 1 : -1] __attribute__((unused));
  
  imath->nbits = envp->scale_bits;
  
  imath->sintab = &trigtab[0];
  imath->costab = &trigtab[64];
}