#include <stdio.h>
#include "cv.h"
#include "cxcore.h"
#include "highgui.h"
#pragma comment(lib,"cv.lib")
#pragma comment(lib,"cxcore.lib")
#pragma comment(lib,"highgui.lib")

void smoothing(unsigned char *out, unsigned char *in, int inHeight, int inWidth, int inChannel, double **filterData, int filterHeight, int filterWidth);

int main(){
   IplImage *in, *out;
   int i,j;
   double filter[3][3] = { {1.0/9.0, 1.0/9.0, 1.0/9.0},
                      {1.0/9.0, 1.0/9.0, 1.0/9.0},
                      {1.0/9.0, 1.0/9.0, 1.0/9.0} };
   double **filterData;
   filterData = (double**)malloc(sizeof(double*)*3);
   for(i = 0; i <3; ++i){
      filterData[i] = (double*)malloc(sizeof(double)*3);
   }
   in = cvLoadImage("./image640.bmp", 0);
   out = cvCreateImage(cvSize(in->width, in->height), in->depth, in->nChannels);

   for(i = 0; i < 3; ++i){
      for(j = 0; j < 3; ++j){
         filterData[i][j] = filter[i][j];
      }
   }
   smoothing((unsigned char*)out->imageData, (unsigned char*)in->imageData, in->height, in->width, in->nChannels, filterData, 3, 3);

   cvNamedWindow("in", 1);
   cvShowImage("in", in);
   cvNamedWindow("out", 1);
   cvShowImage("out", out);
   cvWaitKey(-1);

   cvDestroyWindow("in");
   cvDestroyWindow("out");

   cvReleaseImage( &in );
   cvReleaseImage( &out );


   return 0;
}


void smoothing(unsigned char *out, unsigned char *in, int inHeight, int inWidth, int inChannel, double **filterData, int filterHeight, int filterWidth){
   int i, j, k, l;
   int index;
   int widthStep;
   double tmp;

   widthStep = inWidth * inChannel;
   if(widthStep % 4 != 0){
      widthStep = widthStep + 4- widthStep%4;
   }

   for(i = 0; i < inHeight; ++i){
      for(j = 0; j < inWidth; ++j){
         // 配列を超える場合は平滑化しない
         if( (i-(filterHeight/2) < 0) ||
               (i+(filterHeight/2) > inHeight) ||
               (j-(filterWidth/2) < 0) ||
               (j+(filterWidth/2) > inWidth) ){
            out[i * widthStep + j] = in[i * widthStep + j];
            continue;
         }
         tmp = 0.0;
         for(k = 0; k < filterHeight; ++k){
            for(l = 0; l < filterWidth; ++l){
               tmp += (double)in[(i-(int)(filterHeight/2-k))*widthStep + j-(int)(filterWidth/2-l)] * filterData[k][l];
            }
         }
         out[i * widthStep + j] = (unsigned char)tmp;
      }
   }
}