#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>

static void calcSNR(unsigned char *org, unsigned char *new,
		    int w, int h, double *pv, double *pe , int c, int type);

FILE *out_name_Y, *out_name_U, *out_name_V;


main(){

  int Max_Frame, i,j,k, p = 0;
  FILE *fd;
  FILE *par;
  char org_Y[128], org_U[128], org_V[128];
  char new_Y[128], new_U[128], new_V[128];
  char error_Y[128], error_U[128], error_V[128];	//darshan

  int chrom_hize,chrom_vsize;
  int width, height, chrom_width, chrom_height, size;
  int horizontal, vertical, horizontal1, vertical1;
  unsigned char *org[3];
  unsigned char *new[3];
  unsigned char *error[3];	//darshan
  int counter =0 ;
  double e, v;
  int c, type;

  out_name_Y = fopen("SNR_Y.out", "w");
  out_name_U = fopen("SNR_U.out", "w");
  out_name_V = fopen("SNR_V.out", "w");

  if((par = fopen("SNR.par", "r")) == NULL)
    printf("Warnning !!! FILE SNR.par could not open\n");
  else{
    fscanf(par, "%d %d %d", &width, &height, &Max_Frame);
  }

  fclose(par);

  //  printf(" W: %d \tH: %d\t MAX:%d\n", width, height, Max_Frame);
  Max_Frame = Max_Frame + 1;
  printf("Maxframe=%d\n", Max_Frame);		//darshan
  horizontal = width;
  vertical = height;

  chrom_width = width/2;
  chrom_height = height/2;

  horizontal1 = chrom_width;
  vertical1 = chrom_height;


  fprintf(out_name_Y,"Width: %d\tHeight: %d\tTotal Frame: %d\n", width, height, Max_Frame);
  fprintf(out_name_U,"Width: %d\tHeight: %d\tTotal Frame: %d\n", chrom_width, chrom_height, Max_Frame);
  fprintf(out_name_V,"Width: %d\tHeight: %d\tTotal Frame: %d\n", chrom_width, chrom_height, Max_Frame);


  //printf(" width = %d height = %d \n", width, height);
  //Dynamic memory allocation
  for(j=0; j< 3; j++){
    size = (j==0) ? width*height : chrom_width*chrom_height;
    //printf("size = %d\n", size);
    org[j] = (unsigned char *)malloc(size);
    new[j] = (unsigned char *)malloc(size);
    error[j] = (unsigned char *)malloc(size);

  }


  for(k = 0; k< Max_Frame; k++){
    fprintf(out_name_Y,"\n\n\nFrame number  %d\n",k);
    fprintf(out_name_U,"\n\n\nFrame number  %d\n",k);
    fprintf(out_name_V,"\n\n\nFrame number  %d\n",k);
    printf("SNR:Frame number %d \n", k);

    /************* Original Y **************/
    sprintf(org_Y, "org%d.Y", k);
    //printf("org:Y = %s\t", org_Y);
    if((fd = fopen(org_Y,"rb")) == NULL){
         printf(" Couldn't open %s\n", org_Y);
    }
    else{
      for(i = 0; i < vertical; i++)
	fread(org[0]+i*width, 1, horizontal, fd);
    }

    fclose(fd);

    /************* Original U **************/
    sprintf(org_U, "org%d.U", k);
    //printf("org:U = %s\t", org_U);
    if((fd = fopen(org_U,"rb")) == NULL){
         printf(" Couldn't open %s\n", org_U);
    }
    else{
      for(i = 0; i < vertical1; i++)
	fread(org[1]+i*chrom_width, 1, horizontal1, fd);
    }

    fclose(fd);

    /************* Original V **************/
    sprintf(org_V, "org%d.V", k);
    //printf("org:V = %s\n", org_V);
    if((fd = fopen(org_V,"rb")) == NULL){
         printf(" Couldn't open %s\n", org_V);
    }
    else{
      for(i = 0; i < vertical1; i++)
	fread(org[2]+i*chrom_width, 1, horizontal1, fd);
    }

    fclose(fd);

//Reading the YUV for the reconstructed video buffer
    /************* NEW Y **************/
    sprintf(new_Y, "new%d.Y", k);
    //printf("new:Y = %s\t", new_Y);
    if((fd = fopen(new_Y,"rb")) == NULL){
         printf(" Couldn't open %s\n", new_Y);
    }
    else{
      for(i = 0; i < vertical; i++)
	fread(new[0]+i*width, 1, horizontal, fd);
    }

    fclose(fd);
    
    /************* NEW U **************/
    sprintf(new_U, "new%d.U", k);
    //printf("new:U = %s\t", new_U);
    if((fd = fopen(new_U,"rb")) == NULL){
         printf(" Couldn't open %s\n", new_U);
    }
    else{
      for(i = 0; i < vertical1; i++)
	fread(new[1]+i*chrom_width, 1, horizontal1, fd);
    }

    fclose(fd);

    /************* NEW V **************/
    sprintf(new_V, "new%d.V", k);
    //printf("new:V = %s\n", new_V);
    if((fd = fopen(new_V,"rb")) == NULL){
         printf(" Couldn't open %s\n", new_V);
				        }
    else{
      for(i = 0; i < vertical1; i++)
	fread(new[2]+i*chrom_width, 1, horizontal1, fd);
        }
    fclose(fd);

//darshan
//generating the error buffers
for(i = 0; i < vertical; i++)
for(j = 0; j < horizontal; j++)
{
//printf("org0[i]=%d new0[i] =%d\n",*(org[0]+i*width),*(new[0]+i*width));
 /*   *(error[0]+i*width) = abs((*(org[0]+i*width) - *(new[0]+i*width)));
    if((*(error[0]+i*width)) != 0 )
    {
        *(error[0]+i*width) =153;
	printf("hit for error\n");

	}
    else
    {
    *(error[0]+i*width) = 153;
    printf("no error\n");
    }*/

    *(error[0]+i*width+j) = 0.3*(*(org[0]+i*width+j) - *(new[0]+i*width+j));
//     *(error[0]+i*width+j) = 0;
//    *(error[0]+i*width) =(*(new[0]+i*width)- *(org[0]+i*width));
//      *(error[1]+i*width) = 255;
//printf(" org[i] =%d\n",*(org[0]+i*width));
//printf(" error0[i] =%d\n",*(error[0]+i*width));

}
printf("completed generating errors for Y\n");
for(i = 0; i < vertical1; i++)
for(j = 0; j < horizontal1; j++)
{
    *(error[1]+i*chrom_width+j) = 0;
    *(error[2]+i*chrom_width+j) = 0;

//     *(error[1]+i*chrom_width+j)  = 0.59*(*(org[1]+i*chrom_width+j) - *(new[1]+i*chrom_width+j));
//     *(error[2]+i*chrom_width+j)  = 0.11*(*(org[2]+i*chrom_width+j) - *(new[2]+i*chrom_width));
    // printf("Notification of errors for U&V\n");
   // *(error[1]+i*chrom_width) = 24*((*(org[1]+i*chrom_width) - *(new[1]+i*chrom_width)));
//	*(error[2]+i*chrom_width) = 24*((*(org[2]+i*chrom_width) - *(new[2]+i*chrom_width)));
//    *(error[2]+i*chrom_width) = 128;
//    printf(" error0[i] =%d\n",*(error[2]+i*chrom_width));
}

printf("completed generating errors for U&V\n");

//Writing the YUV for the error video buffer
    /************* error Y ************/
    sprintf(error_Y, "error%d.Y", k);
    //printf("new:Y = %s\t", new_Y);
    unlink(new_Y);
    if((fd = fopen(error_Y,"wb")) == NULL){
         printf(" Couldn't open %s\n", error_Y);
    }
    else
    {
      for(i = 0; i < vertical; i++){
	fwrite(org[0]+i*width, 1, horizontal, fd);
//	printf("subtracted error[0] buffer value=%d\n",*(error[0]+i*width));
//	printf("original   org[0] buffer value=%d\n",*(error[0]+i*width));
//	getchar();
	}
   // printf("saving darshan Y file\n");
    }

    fclose(fd);

    /************* error U **************/
    sprintf(error_U, "error%d.U", k);
    //printf("new:U = %s\t", new_U);
    unlink(new_U);
    if((fd = fopen(error_U,"wb")) == NULL){
         printf(" Couldn't open %s\n", error_U);
    }
    else{
      for(i = 0; i < vertical1; i++)
	fwrite(error[1]+i*chrom_width, 1, horizontal1, fd);

       // printf("saving darshan U file\n");
    }

    fclose(fd);

    /************* error V **************/
    sprintf(error_V, "error%d.V", k);
    //printf("new:V = %s\n", new_V);
    unlink(new_V);
    if((fd = fopen(error_V,"wb")) == NULL){
         printf(" Couldn't open %s\n", error_V);
				        }
    else{
      for(i = 0; i < vertical1; i++)
	fwrite(error[2]+i*chrom_width, 1, horizontal1, fd);

         // printf("saving darshan V file\n");
        }
    fclose(fd);




//Generating the SNR files below
/*
    for(i=0; i<3; i++){
      if(i == 0){
	fprintf(out_name_Y,"SNR_Y \n");
	width = horizontal;
	height = vertical;
	c = 1;
	type = 0;
      }
      else if(i == 1){
	fprintf(out_name_U,"SNR_U \n");
	width = chrom_width;
	height = chrom_height;
	c = 2;
	type = 1;
      }

      else if(i == 2){
        fprintf(out_name_V,"SNR_V \n");
	width = chrom_width;
	height = chrom_height;
	c = 2;
	type = 2;
      }
      calcSNR(org[i], new[i], width, height, &v, &e, c, type);
      printf("%3.3g ", 10.0 * log10(255.0*255.0/(e)));
     }

    */ //End of snr file generation
    }

//Freeing the buffers used for original and new YUVs
    for(j=0; j< 3; j++){
      free(org[j]);
      free(new[j]);
      free(error[j]);
    }
    //    printf("\nWidth = %d\tHeight = %d\tTotal Frame=%d\n", horizontal, vertical, Max_Frame);
   
  fclose(out_name_Y);
  fclose(out_name_U);
  fclose(out_name_V);

}


static void calcSNR(org, new, w, h, pv, pe, c, type)
unsigned char *org;
unsigned char *new;
int w, h, c;
double *pv, *pe;
{

  int i , j, k = 0;
  double v1,s1,s2,e2;
  int mb_count, row, col;


  mb_count = (w * h)/(256/(c*c));
  

  while(k < mb_count){


    row  = (int)(k/(w/(16/c)));
    col  = k%(w/(16/c));
    s1 = s2 = e2 = 0.0;
  
    for(j=0; j<16; ){
      j=j+c;
      for(i=0; i<16;){
	v1 = org[(w/c)*(row*16/c + (int)(j/c)) + (col*16)/c + (int)(i/c)];
	s1+= v1;
	s2+= v1*v1;
	v1-= new[(w/c)*(row*16/c + (int)(j/c)) + (col*16)/c + (int)(i/c)];
	e2+= v1*v1;
	i=i+c;
      }
    }


  s1 /= w * h;
  s2 /= w * h;
  e2 /= w * h;
  
  if(e2 == 0.0) e2 = 0.00001;

  *pv = s2 - s1 * s1;
  *pe = e2;

  if(type == 0) fprintf(out_name_Y,"%3.3g ", 10.0 * log10(255.0*255.0/(*pe)));
  if(type == 1) fprintf(out_name_U,"%3.3g ", 10.0 * log10(255.0*255.0/(*pe)));
  if(type == 2) fprintf(out_name_V,"%3.3g ", 10.0 * log10(255.0*255.0/(*pe)));

  if(((k>1)&&((k+1) % (w/(16/c))) == 0)&&(type == 0))fprintf(out_name_Y,"\n");
  if(((k>1)&&((k+1) % (w/(16/c))) == 0)&&(type == 1))fprintf(out_name_U,"\n");
  if(((k>1)&&((k+1) % (w/(16/c))) == 0)&&(type == 2))fprintf(out_name_V,"\n");
  k++;
  }

}