// Program to demonstrate use of IPConvSymC, a templated linear symmetric
// convolution filter.

#include "amma/Image/IPConvSym.hh"
#include "amma/Image/IPGaussConv.hh"
#include "amma/DP/ComposeSE.hh" // only needed for 2nd filter method
#include "amma/SDFunct1.hh" // only needed for the predefined Binomial example

int main ()
{
  using namespace IPSpatFilterN;
  NumImageC<RealT> in(6,6);
  in.Fill(1.0);
  NumImageC<RealT> out;
  SArray1dC<RealT> coeff(3);
  coeff[0] = 6; coeff[1] = 4; coeff[2] = 1; // i.e. 5-tap filter with values 1,4,6,4,1

  // Basic method to apply vertical filter to image, with default erode option
  out = IPConvSymC<RealT,RealT>(coeff,Vertical).Apply(in);
  cout << out << "\n\n";

  // The same method, but more compact, for a horizontal filter, expanding
  // output to include all non-zero information.  The technique extends the i/p
  // image with black pixels.
  cout << (IPConvSymC<RealT,RealT>(coeff,Horizontal,Expand,PadBlack).Apply(in))
       << "\n\n";

  // Alternative method using DPComposeSE stream, preserving original input
  // image size.  The technique again extends the i/p image with black pixels,
  // and then "renormalises" the pixels near the border to preserve the
  // d.c. level.
  using namespace DPComposeSE;
  in >> IPConvSymC<RealT,RealT>(coeff,TwoD,Original) >> out;
  cout << out << "\n\n";

  // You could create the mask from one of the SDFunction1dC functions,
  // e.g. Binomial().  But you <b>must</b> use an odd size, and select just the
  // right-hand half:
  IntT size=5;
  //N.B. Funny initialisation using static member function.
  SDFunction1dC mask_two_sided(SDFunction1dC::Binomial(size,true)); 
  SArray1dC<RealT> mask((size+1)/2); 
  for (UIntT i=0; i<mask.Size(); ++i)
    mask[i] = mask_two_sided[i+(size/2)];
  in >> IPConvSymC<RealT,RealT>(mask,Horizontal,Expand,PadBlack) >> out;
  cout << out << "\n\n";

  // But much better, for the Binomial example, you could use IPGaussConvolveC
  // to do all this for you, & you should get the same answer:
  in >> IPGaussConvolveC<RealT>(5,Horizontal,Expand,PadBlack) >> out;
  cout << out << "\n\n";

}