/*# proc: rm_br_corner_1_sided - removes the bot-right corner of line data# proc:                using a slope projection from one side.# proc: rm_br_corner_2_sided - removes the bot-right corner of line data# proc:                by projecting a cut line between two points.# proc: br_corner_cut_slope - determines the slope for cutting off the# proc:                bot-right corner of line data.# proc: sum_dys_br_corner - computes changes in y used to estimate the# proc:                slope along which the bot-right corner will be cut.*/#include <stdio.h>#include <values.h>#include <defs.h>#include <rmline.h>#include <mytrace.h>/***************************************************************************//* rm_br_corner_1_sided - removes the bottom-right corner of line data     *//* using a slope projection from the character data on the top side of the *//* corner.                                                                 *//***************************************************************************/rm_br_corner_1_sided(rs, re, msw, ebin, sw, fsy, tsy, nsw, cdata, w, h)int rs, re, msw, *ebin, *sw, *fsy, *tsy, nsw;unsigned char *cdata;int w, h;{   int rx, ry;   float rm;   int crx, slimit;   int take_step;   /* determine the slope of the cut, from the character data on the */   /* top-right side of the corner */   br_corner_cut_slope(&rm, &rx, &ry, rs, re, msw, ebin, fsy, tsy, nsw, cdata, w, h);   /* can't have cut with positive slope if really br corner */   if((rm == MAXFLOAT) || (rm > 0.0)) {      my_trace("br corner not found\n");      return;   }   /* project cut from the white pixel below ry */   ry = min(h-1, ry+1);   crx = rx;   slimit = step_limit2(msw);   take_step = TRUE;   /* while right steps do not exceed the left edge of the run of unerased slices */   /* and other stopping conditions not met ... */   while((crx >= rs) && (take_step)){      /* take next step */      take_step = process_b_corner_slice(crx, rm, rx, ry, rs, re, slimit,                                          ebin, sw, fsy, tsy, nsw, cdata, w, h);      crx--;   }}/***************************************************************************//* rm_br_corner_2_sided - removes the bottom-right corner of line data by  *//* projecting a cut line connecting the top-right of the run of unerased   *//* slices to the top-right point where the 2nd derivative elbow (or        *//* inflection) was detected.                                               *//***************************************************************************/rm_br_corner_2_sided(elbow_x, rs, re, msw, ebin, sw, fsy, tsy, nsw, cdata, w, h)int elbow_x, rs, re, msw, *ebin, *sw, *fsy, *tsy, nsw;unsigned char *cdata;int w, h;{   int rx, ry;   float rm, compute_slope();   int crx, slimit;   int take_step;   rx = re;   crx = rx;   ry = fsy[min(w-1, re+1)];   slimit = step_limit(msw);   /* compute the slope of the cut line projection */   rm = compute_slope((float)rx, (float)ry, (float)elbow_x, (float)tsy[elbow_x]);   take_step = TRUE;   /* while right steps do not exceed the elbow */   /* and other stopping conditions not met ... */   while((crx >= elbow_x) && (take_step)){      /* take next step */      take_step = process_b_corner_slice(crx, rm, rx, ry, rs, re, slimit,                                          ebin, sw, fsy, tsy, nsw, cdata, w, h);      crx--;   }}/***************************************************************************//* br_corner_cut_slope - determines the slope of the cut for a bottom-right*//* corner by measuring first derivative changes in y between the top of    *//* the line to the character data on the top-right side of the corner for  *//* a specified duration.                                                   *//***************************************************************************/br_corner_cut_slope(rm, rx, ry, rs, re, msw, ebin, fsy, tsy, nsw, cdata, w, h)float *rm;int *rx, *ry;int rs, re, msw, *ebin, *fsy, *tsy, nsw;unsigned char *cdata;int w, h;{   int rdys, nrdys;   /* measure the first derivative changes in y between the top of the line */   /* and the character data on the top-right side of a bottom-right corner. *//*                                  /                                 /^                                / | delta ys                      |        /  v                   ----------------                      |      xx|                      |    xxxx|                   ----------------*/   sum_dys_br_corner(&rdys, &nrdys, rx, ry, rs, re, msw, ebin, fsy, tsy, nsw, cdata, w, h);   /* if charater data was found to compute delta ys ... */   if(nrdys != 0){      /* calculate the slope from the delta y's */      *rm = rdys /(float)nrdys;   }   /* otherwise the slope is vetical */   else      *rm = MAXFLOAT;   my_trace1("br corner cut slope = %f\n", *rm);}/***************************************************************************//* sum_dys_br_corner - measures the first derivative changes in y between  *//* the top of the line and the character data on the top-right side of a   *//* bottom-right corner for a specified duration. The resulting delta ys    *//* are used to compute a slope along which the bottom-right corner will be *//* cut.                                                                    *//***************************************************************************/sum_dys_br_corner(rdys, nrdys, rx, ry, rs, re, msw, ebin, fsy, tsy, nsw, cdata, w, h)int *rdys, *nrdys, *rx, *ry;int rs, re, msw, *ebin, *tsy, *fsy, nsw;unsigned char *cdata;int w, h;{   int i, x, sum = 0, c = 0, diff;   int oy, ny, slimit;   /* if there is no data to the right of the run of unerased slices ... */   if(re == (nsw - 1)){      /* return 0 delta dys ==> vertical slope */      *rdys = 0;      *nrdys = 0;      *rx = re;      *ry = fsy[re];      return;   }   /* start dys to the right of the run of unerased slices */   x = re + 1;   /* locate the first black pixel upward */   /* this black pixel "should" be part of the character data */   if((oy = find_pix_north(BLACK_PIX, x, max(0,fsy[x]-1), cdata, w, h)) != NOT_FOUND){      slimit = step_limit(msw);      /* compute the distance between the top of the line and the */      /* character data */      diff = oy - fsy[x];   }   /* if character data not found */   /* OR the delta is too big ... */   if((oy == NOT_FOUND) || (-diff > slimit)){      /* return 0 delta dys ==> vertical slope */      *rdys = 0;      *nrdys = 0;      *rx = x;      *ry = fsy[x];      return;   }   /* store the very first point of the character data */   /* to the right of the run of unerased slices */   *rx = x;   *ry = oy;   /* bump to the next slice on right */   x++;   /* for the specified duration */   /* AND while slices to the right */   /* AND while curent slice has been erased ... */   for(i = 1; (i < RUN_DYS)&&(x<w)&&(ebin[x] == ERASED); i++,x++){      /* find the edge of the character data upward */      if((ny = find_pix_north(BLACK_PIX, x, max(0,fsy[x]-1), cdata, w, h)) != NOT_FOUND)         /* compute change in previous and current slices' character data ys */         diff = ny - oy;      /* if character data not found */      /* OR the delta is too big, then stop computing delta ys */      if((ny == NOT_FOUND) || (-diff > slimit))         break;      /* otherwise accumulate new delta y */      sum += diff;      oy = ny;      c++;   }   *rdys = sum;   *nrdys = c;}