/*# proc: compute_hist - computes a horizontal or vertical spatial histogram# proc:                from a binary bitmap.# proc: compute_x_hist - computes a horizontal spatial histogram from a# proc:                  binary bitmap.# proc: compute_y_hist - computes a vertical spatial histogram from a# proc:                  binary bitmap.# proc: hist_nruns_hori - given a list of horizontal runs, computes a histogram# proc:                   by summing the top-n longest runs in each row.# proc: hist_nruns_hori2 - given a list of horizontal runs, computes a histogram# proc:                 by summing the top-n longest runs in each row and returns# proc:                 the sorted order of the runs.*//*************************************************************//*                                                           *//*       File Name:    Histogram.c                           *//*       Package:      Spatial Histogram Computations        *//*                                                           *//*       Contents:     Compute_Hist()                        *//*                     Compute_X_Hist()                      *//*                     Compute_Y_Hist()                      *//*************************************************************/#include <stdio.h>#include <math.h>#include <memory.h>#include <masks.h>#include <bits.h>#include <defs.h>#include <histgram.h>/************************************************************//*         Routine:   Compute_Hist()                        *//*         Author:    Michael D. Garris                     *//*         Date:      7/21/89                               *//************************************************************//*************************************************************//* Compute_hist() Serves as a switch for orthogonal hist-    *//* ogram orientations.                                       *//*************************************************************/void compute_hist(data,width,height,orient,bins,len)unsigned char *data;int width,height,orient,**bins,*len;{    switch (orient){       case Y_HIST:            compute_y_hist(data,width,height,bins,len);            break;       case X_HIST:            compute_x_hist(data,width,height,bins,len);            break;       default:            fatalerr("comput_hist","Unknown histogram orientation",NULL);    }}/************************************************************//*         Routine:   Compute_X_Hist()                      *//*         Author:    Michael D. Garris                     *//*         Date:      7/21/89                               *//************************************************************//*************************************************************//* Compute_x_hist() Computes an X-oriented histogram on the  *//* defined rectangular image region passed.                  *//*************************************************************/void compute_x_hist(data,width,height,bins,len)unsigned char *data;int width,height,**bins,*len;{int y, bytewidth;   bytewidth = width >> 3;   malloc_int(bins, height, "compute_x_hist : bins");   for ( y = 0 ; y < height ; y++, data += bytewidth )      (*bins)[y] = black_pixel_count(data, width, 1);      *len = height;}/************************************************************//*         Routine:   Compute_Y_Hist()                      *//*         Author:    Michael D. Garris                     *//*         Date:      7/21/89                               *//************************************************************//*************************************************************//* Compute_y_hist() Computes a Y-oriented histogram on the   *//* defined rectangular image region passed.                  *//*************************************************************/void compute_y_hist(data,width,height,bins,len)unsigned char *data;int width,height,**bins,*len;{   int bytewidth,bytelines,y,x_byte,bit,bnum,memsize;   unsigned char byte;   bytewidth = width/8;   memsize = width * sizeof(int);   malloc_int(bins, memsize, "compute_y_hist : bins");   memset((*bins),0,memsize);   for(y = 0; y < height; y++){      bnum = 0;      bytelines = y * bytewidth;      for(x_byte = 0; x_byte < bytewidth; x_byte++){         byte = *(data + bytelines + x_byte);         for(bit = 7; bit >= 0; bit--){            ((*bins)[bnum])+= get_bit(byte,bit);            bnum++;         }      }   }   *len = width;}/**********************************************************/hist_nruns_hori(grab, rx, ry, rlen, nruns, w, h, bins, nbins)int grab, *rx, *ry, *rlen, nruns, w, h;int **bins, *nbins;{   int *rank, *sort_index_on_int_2id();   int ri, cy, c;   rank = sort_index_on_int_2id(ry, rlen, nruns);   calloc_int(bins, h, "hist_nruns_hori : bins");   *nbins = h;   ri = 0;   cy = 0;   while(ri < nruns){      c = 0;      while((ri < nruns) && (ry[rank[ri]] == cy) && (c < grab)){         (*bins)[cy] += rlen[rank[ri]];         c++;         ri++;      }      while((ri < nruns) && (ry[rank[ri]] == cy))         ri++;      cy++;   }   free(rank);}/**********************************************************/hist_nruns_hori2(grab, rx, ry, rlen, nruns, w, h, bins, nbins, rank)int grab, *rx, *ry, *rlen, nruns, w, h;int **bins, *nbins, **rank;{   int *sort_index_on_int_2id();   int ri, cy, c;   (*rank) = sort_index_on_int_2id(ry, rlen, nruns);   calloc_int(bins, h, "hist_nruns_hori2 : bins");   *nbins = h;   ri = 0;   cy = 0;   while(ri < nruns){      c = 0;      while((ri < nruns) && (ry[(*rank)[ri]] == cy) && (c < grab)){         (*bins)[cy] += rlen[(*rank)[ri]];         c++;         ri++;      }      while((ri < nruns) && (ry[(*rank)[ri]] == cy))         ri++;      cy++;   }}