/*---------------------------------------------------------------------------*/
/* Program:  header.c                                                        */
/*                                                                           */
/* Purpose:  This program reads the header from an image in KUIM format      */
/*           and prints this information.                                    */
/*                                                                           */
/* Author:   John Gauch                                                      */
/*                                                                           */
/* Date:     March 23, 1994                                                  */
/*                                                                           */
/* Note:     Copyright (C) The University of Kansas, 1994                    */
/*---------------------------------------------------------------------------*/
#include <IM.h>

/*---------------------------------------------------------------------------*/
/* Purpose:  This is the main program.                                       */
/*---------------------------------------------------------------------------*/
int main(int argc, char *argv[])
{
   /* Image variables */
   char Name1[50];
   IM_TYPE *Image1;
   INT_TYPE *Data1;
   INT_TYPE *Histo;
   FLOAT_TYPE *Data2;
   int PixType, Xdim, Ydim, Zdim, DimCnt;
   char Title[nTITLE];

   /* Program variables */
   int Debug = FALSE;
   int i = 0;
   int Count;
   int Min1, Max1;
   float Min2, Max2;
   double Prob, Entropy;
   float Ave, Ave2, Var;

   /* Interpret program options */
   printf("HEADER Program - KUIM Version 1.0\n\n");
   while ((++i < argc) && (argv[i][0] == '-'))
      switch (argv[i][1])
      {
      case 'd':
	 Debug = TRUE;
	 break;
      default:
	 Error("Invalid option encountered");
	 break;
      }

   /* Check number of file names */
   if (argc - i != 1)
   {
      fprintf(stderr, "Usage: header [options] infile\n");
      fprintf(stderr, "       [-d]    Print debugging information\n");
      exit(1);
   }

   /* Get image file names from argument list */
   if (sscanf(argv[i++], "%s", Name1) == 0)
      Error("Could not get input file name");

   /* Read input image */
   Image1 = im_open(Name1, &PixType, &Xdim, &Ydim, &Zdim, &DimCnt);
   printf("Image Name       = %s\n", Name1);

   /* Print image dimension information  */
   if (DimCnt == 0)
      printf("Image is zero dimensional\n");
   else if (DimCnt == 1)
      printf("Image Dimensions = %d\n", Xdim);
   else if (DimCnt == 2)
      printf("Image Dimensions = %d,%d\n", Xdim, Ydim);
   else if (DimCnt == 3)
      printf("Image Dimensions = %d,%d,%d\n", Xdim, Ydim, Zdim);

   /* Print pixel type information */
   switch (PixType)
   {
   case BYTE:
      printf("Image Type       = BYTE\n");
      break;
   case SHORT:
      printf("Image Type       = SHORT\n");
      break;
   case INT:
      printf("Image Type       = INT\n");
      break;
   case FLOAT:
      printf("Image Type       = FLOAT\n");
      break;
   case DOUBLE:
      printf("Image Type       = DOUBLE\n");
      break;
   case COMPLEX:
      printf("Image Type       = COMPLEX\n");
      break;
   case COLOR:
      printf("Image Type       = COLOR\n");
      break;
   case PSEUDO:
      printf("Image Type       = PSEUDO\n");
      break;
   case JPEG_GRAY:
      printf("Image Type       = JPEG_GRAY\n");
      break;
   case JPEG_RGB:
      printf("Image Type       = JPEG_RGB\n");
      break;
   default:
      Error("Invalid image type");
   }

   /* Print image title */
   im_get_title(Image1, Title);
   if (strlen(Title) > 0)
      printf("Image Title      = '%s'\n", Title);

   /* Print min and max values and entropy */
   if (PixType == BYTE || PixType == SHORT || PixType == INT || PixType == JPEG_GRAY)
   {
      /* Find intensity range */
      Data1 = (INT_TYPE *) im_alloc1D(Image1, INT);
      im_read(Image1, INT, (char *) Data1);
      Ave = Ave2 = Var = 0.0;
      Min1 = Max1 = Data1[0];
      Count = Xdim * Ydim * Zdim;
      for (i = 0; i < Count; i++)
      {
	 if (Min1 > Data1[i])
	    Min1 = Data1[i];
	 else if (Max1 < Data1[i])
	    Max1 = Data1[i];
	 Ave += Data1[i];
	 Ave2 += Data1[i] * Data1[i];
      }
      Ave /= Count;
      Ave2 /= Count;
      Var = Ave2 - Ave * Ave;
      printf("Image Range      = [%d,%d]\n", Min1, Max1);

      /* Calculate entropy */
      Image1 = im_create("/dev/null", INT, Max1 - Min1 + 1, 1, 1);
      Histo = (INT_TYPE *) im_alloc1D(Image1, INT);
      for (i = 0; i < (Max1 - Min1 + 1); i++)
	 Histo[i] = 0;
      for (i = 0; i < Count; i++)
	 Histo[Data1[i] - Min1]++;
      Entropy = 0;
      for (i = 0; i < (Max1 - Min1 + 1); i++)
	 if (Histo[i] > 0)
	 {
	    Prob = (double) Histo[i] / (double) Count;
	    Entropy -= Prob * log(Prob) / log(2.0);
	 }
      printf("Entropy  = %7.2lf\n", Entropy);
      printf("Mean     = %7.2f\n", Ave);
      printf("Variance = %7.2f\n", Var);
      printf("StdDev   = %7.2f\n", (float) sqrt((double) Var));
   }

   /* Print min and max values and entropy */
   else if (PixType == FLOAT || PixType == DOUBLE)
   {
      /* Find intensity range */
      Data2 = (FLOAT_TYPE *) im_alloc1D(Image1, FLOAT);
      im_read(Image1, FLOAT, (char *) Data2);
      Ave = Ave2 = Var = 0.0;
      Min2 = Max2 = Data2[0];
      Count = Xdim * Ydim * Zdim;
      for (i = 0; i < Count; i++)
      {
	 if (Min2 > Data2[i])
	    Min2 = Data2[i];
	 else if (Max2 < Data2[i])
	    Max2 = Data2[i];
	 Ave += Data2[i];
	 Ave2 += Data2[i] * Data2[i];
      }
      Ave /= Count;
      Ave2 /= Count;
      Var = Ave2 - Ave * Ave;
      printf("Image Range      = [%f..%f]\n", Min2, Max2);

      /* Calculate entropy */
      Image1 = im_create("/dev/null", INT, (int) (Max2 - Min2 + 1), 1, 1);
      Histo = (INT_TYPE *) im_alloc1D(Image1, INT);
      for (i = 0; i < (Max2 - Min2 + 1); i++)
	 Histo[i] = 0;
      for (i = 0; i < Count; i++)
	 Histo[(int) (Data2[i] - Min2)]++;
      Entropy = 0;
      for (i = 0; i < (Max2 - Min2 + 1); i++)
	 if (Histo[i] > 0)
	 {
	    Prob = (double) Histo[i] / (double) Count;
	    Entropy -= Prob * log(Prob) / log(2.0);
	 }
      printf("Entropy  = %7.2lf\n", Entropy);
      printf("Mean     = %7.2f\n", Ave);
      printf("Variance = %7.2f\n", Var);
      printf("StdDev   = %7.2f\n", (float) sqrt((double) Var));
   }
   return (0);
}