makerow.h File Reference

#include "params.h"
#include "ocrblock.h"
#include "blobs.h"
#include "blobbox.h"
#include "statistc.h"

Go to the source code of this file.

Enumerations
enum	OVERLAP_STATE { ASSIGN, REJECT, NEW_ROW }
enum	ROW_CATEGORY { ROW_ASCENDERS_FOUND, ROW_DESCENDERS_FOUND, ROW_UNKNOWN, ROW_INVALID }

Functions
void	get_min_max_xheight (int block_linesize, int *min_height, int *max_height)
ROW_CATEGORY	get_row_category (const TO_ROW *row)
bool	within_error_margin (float test, float num, float margin)
void	fill_heights (TO_ROW *row, float gradient, int min_height, int max_height, STATS *heights, STATS *floating_heights)
float	make_single_row (ICOORD page_tr, bool allow_sub_blobs, TO_BLOCK *block, TO_BLOCK_LIST *blocks)
float	make_rows (ICOORD page_tr, TO_BLOCK_LIST *port_blocks)
void	make_initial_textrows (ICOORD page_tr, TO_BLOCK *block, FCOORD rotation, bool testing_on)
void	fit_lms_line (TO_ROW *row)
void	compute_page_skew (TO_BLOCK_LIST *blocks, float &page_m, float &page_err)
void	vigorous_noise_removal (TO_BLOCK *block)
void	cleanup_rows_making (ICOORD page_tr, TO_BLOCK *block, float gradient, FCOORD rotation, int32_t block_edge, bool testing_on)
void	delete_non_dropout_rows (TO_BLOCK *block, float gradient, FCOORD rotation, int32_t block_edge, bool testing_on)
bool	find_best_dropout_row (TO_ROW *row, int32_t distance, float dist_limit, int32_t line_index, TO_ROW_IT *row_it, bool testing_on)
TBOX	deskew_block_coords (TO_BLOCK *block, float gradient)
void	compute_line_occupation (TO_BLOCK *block, float gradient, int32_t min_y, int32_t max_y, int32_t *occupation, int32_t *deltas)
void	compute_occupation_threshold (int32_t low_window, int32_t high_window, int32_t line_count, int32_t *occupation, int32_t *thresholds)
void	compute_dropout_distances (int32_t *occupation, int32_t *thresholds, int32_t line_count)
void	expand_rows (ICOORD page_tr, TO_BLOCK *block, float gradient, FCOORD rotation, int32_t block_edge, bool testing_on)
void	adjust_row_limits (TO_BLOCK *block)
void	compute_row_stats (TO_BLOCK *block, bool testing_on)
float	median_block_xheight (TO_BLOCK *block, float gradient)
int	compute_xheight_from_modes (STATS *heights, STATS *floating_heights, bool cap_only, int min_height, int max_height, float *xheight, float *ascrise)
int32_t	compute_row_descdrop (TO_ROW *row, float gradient, int xheight_blob_count, STATS *heights)
int32_t	compute_height_modes (STATS *heights, int32_t min_height, int32_t max_height, int32_t *modes, int32_t maxmodes)
void	correct_row_xheight (TO_ROW *row, float xheight, float ascrise, float descdrop)
void	separate_underlines (TO_BLOCK *block, float gradient, FCOORD rotation, bool testing_on)
void	pre_associate_blobs (ICOORD page_tr, TO_BLOCK *block, FCOORD rotation, bool testing_on)
void	fit_parallel_rows (TO_BLOCK *block, float gradient, FCOORD rotation, int32_t block_edge, bool testing_on)
void	fit_parallel_lms (float gradient, TO_ROW *row)
void	make_baseline_spline (TO_ROW *row, TO_BLOCK *block)
bool	segment_baseline (TO_ROW *row, TO_BLOCK *block, int32_t &segments, int32_t *xstarts)
double *	linear_spline_baseline (TO_ROW *row, TO_BLOCK *block, int32_t &segments, int32_t xstarts[])
void	assign_blobs_to_rows (TO_BLOCK *block, float *gradient, int pass, bool reject_misses, bool make_new_rows, bool drawing_skew)
OVERLAP_STATE	most_overlapping_row (TO_ROW_IT *row_it, TO_ROW *&best_row, float top, float bottom, float rowsize, bool testing_blob)
int	blob_x_order (const void *item1, const void *item2)
int	row_y_order (const void *item1, const void *item2)
int	row_spacing_order (const void *item1, const void *item2)
void	mark_repeated_chars (TO_ROW *row)

Variables
bool	textord_heavy_nr = FALSE
bool	textord_show_initial_rows = FALSE
bool	textord_show_parallel_rows = FALSE
bool	textord_show_expanded_rows = FALSE
bool	textord_show_final_rows = FALSE
bool	textord_show_final_blobs = FALSE
bool	textord_test_landscape = FALSE
bool	textord_parallel_baselines = TRUE
bool	textord_straight_baselines = FALSE
bool	textord_quadratic_baselines = FALSE
bool	textord_old_baselines = TRUE
bool	textord_old_xheight = TRUE
bool	textord_fix_xheight_bug = TRUE
bool	textord_fix_makerow_bug = TRUE
bool	textord_cblob_blockocc = TRUE
bool	textord_debug_xheights = FALSE
int	textord_test_x = -INT32_MAX
int	textord_test_y = -INT32_MAX
int	textord_min_blobs_in_row = 4
int	textord_spline_minblobs = 8
int	textord_spline_medianwin = 6
int	textord_min_xheight = 10
double	textord_spline_shift_fraction = 0.02
double	textord_spline_outlier_fraction = 0.1
double	textord_skew_ile = 0.5
double	textord_skew_lag = 0.75
double	textord_linespace_iqrlimit = 0.2
double	textord_width_limit = 8
double	textord_chop_width = 1.5
double	textord_minxh = 0.25
double	textord_min_linesize = 1.25
double	textord_excess_blobsize = 1.3
double	textord_occupancy_threshold = 0.4
double	textord_underline_width = 2.0
double	textord_min_blob_height_fraction = 0.75
double	textord_xheight_mode_fraction = 0.4
double	textord_ascheight_mode_fraction = 0.15
double	textord_ascx_ratio_min = 1.2
double	textord_ascx_ratio_max = 1.7
double	textord_descx_ratio_min = 0.15
double	textord_descx_ratio_max = 0.6
double	textord_xheight_error_margin = 0.1
int	textord_lms_line_trials = 12
bool	textord_new_initial_xheight = TRUE
bool	textord_debug_blob = FALSE

Enumeration Type Documentation

OVERLAP_STATE

enum OVERLAP_STATE

Enumerator
ASSIGN
REJECT
NEW_ROW

Definition at line 28 of file makerow.h.

{
  ASSIGN,                        //assign it to row
  REJECT,                        //reject it - dual overlap
  NEW_ROW
};

ROW_CATEGORY

enum ROW_CATEGORY

Enumerator
ROW_ASCENDERS_FOUND
ROW_DESCENDERS_FOUND
ROW_UNKNOWN
ROW_INVALID

Definition at line 35 of file makerow.h.

                  {
  ROW_ASCENDERS_FOUND,
  ROW_DESCENDERS_FOUND,
  ROW_UNKNOWN,
  ROW_INVALID,
};

Function Documentation

adjust_row_limits()

void adjust_row_limits

(

TO_BLOCK *

block

)

adjust_row_limits

Change the limits of rows to suit the default fractions.

Definition at line 1109 of file makerow.cpp.

                        {
  TO_ROW *row;                   //current row
  float size;                    //size of row
  float ymax;                    //top of row
  float ymin;                    //bottom of row
  TO_ROW_IT row_it = block->get_rows ();

  if (textord_show_expanded_rows)
    tprintf("Adjusting row limits for block(%d,%d)\n",
            block->block->pdblk.bounding_box().left(),
            block->block->pdblk.bounding_box().top());
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
    row = row_it.data ();
    size = row->max_y () - row->min_y ();
    if (textord_show_expanded_rows)
      tprintf("Row at %f has min %f, max %f, size %f\n",
              row->intercept(), row->min_y(), row->max_y(), size);
    size /= tesseract::CCStruct::kXHeightFraction +
        tesseract::CCStruct::kAscenderFraction +
        tesseract::CCStruct::kDescenderFraction;
    ymax = size * (tesseract::CCStruct::kXHeightFraction +
                   tesseract::CCStruct::kAscenderFraction);
    ymin = -size * tesseract::CCStruct::kDescenderFraction;
    row->set_limits (row->intercept () + ymin, row->intercept () + ymax);
    row->merged = false;
  }
}

assign_blobs_to_rows()

void assign_blobs_to_rows	(	TO_BLOCK *	block,
		float *	gradient,
		int	pass,
		bool	reject_misses,
		bool	make_new_rows,
		bool	drawing_skew
	)

Definition at line 2280 of file makerow.cpp.

  {
  OVERLAP_STATE overlap_result;  //what to do with it
  float ycoord;                  //current y
  float top, bottom;             //of blob
  float g_length = 1.0f;         //from gradient
  int16_t row_count;               //no of rows
  int16_t left_x;                  //left edge
  int16_t last_x;                  //previous edge
  float block_skew;              //y delta
  float smooth_factor;           //for new coords
  float near_dist;               //dist to nearest row
  ICOORD testpt;                 //testing only
  BLOBNBOX *blob;                //current blob
  TO_ROW *row;                   //current row
  TO_ROW *dest_row = nullptr;       //row to put blob in
                                 //iterators
  BLOBNBOX_IT blob_it = &block->blobs;
  TO_ROW_IT row_it = block->get_rows ();

  ycoord =
    (block->block->pdblk.bounding_box ().bottom () +
    block->block->pdblk.bounding_box ().top ()) / 2.0f;
  if (gradient != nullptr)
    g_length = sqrt (1 + *gradient * *gradient);
#ifndef GRAPHICS_DISABLED
  if (drawing_skew)
    to_win->SetCursor(block->block->pdblk.bounding_box ().left (), ycoord);
#endif
  testpt = ICOORD (textord_test_x, textord_test_y);
  blob_it.sort (blob_x_order);
  smooth_factor = 1.0;
  block_skew = 0.0f;
  row_count = row_it.length ();  //might have rows
  if (!blob_it.empty ()) {
    left_x = blob_it.data ()->bounding_box ().left ();
  }
  else {
    left_x = block->block->pdblk.bounding_box ().left ();
  }
  last_x = left_x;
  for (blob_it.mark_cycle_pt (); !blob_it.cycled_list (); blob_it.forward ()) {
    blob = blob_it.data ();
    if (gradient != nullptr) {
      block_skew = (1 - 1 / g_length) * blob->bounding_box ().bottom ()
        + *gradient / g_length * blob->bounding_box ().left ();
    }
    else if (blob->bounding_box ().left () - last_x > block->line_size / 2
      && last_x - left_x > block->line_size * 2
    && textord_interpolating_skew) {
      //                      tprintf("Interpolating skew from %g",block_skew);
      block_skew *= (float) (blob->bounding_box ().left () - left_x)
        / (last_x - left_x);
      //                      tprintf("to %g\n",block_skew);
    }
    last_x = blob->bounding_box ().left ();
    top = blob->bounding_box ().top () - block_skew;
    bottom = blob->bounding_box ().bottom () - block_skew;
#ifndef GRAPHICS_DISABLED
    if (drawing_skew)
      to_win->DrawTo(blob->bounding_box ().left (), ycoord + block_skew);
#endif
    if (!row_it.empty ()) {
      for (row_it.move_to_first ();
        !row_it.at_last () && row_it.data ()->min_y () > top;
        row_it.forward ());
      row = row_it.data ();
      if (row->min_y () <= top && row->max_y () >= bottom) {
      //any overlap
        dest_row = row;
        overlap_result = most_overlapping_row (&row_it, dest_row,
          top, bottom,
          block->line_size,
          blob->bounding_box ().
          contains (testpt));
        if (overlap_result == NEW_ROW && !reject_misses)
          overlap_result = ASSIGN;
      }
      else {
        overlap_result = NEW_ROW;
        if (!make_new_rows) {
          near_dist = row_it.data_relative (-1)->min_y () - top;
                                 //below bottom
          if (bottom < row->min_y ()) {
            if (row->min_y () - bottom <=
              (block->line_spacing -
            block->line_size) * tesseract::CCStruct::kDescenderFraction) {
                                 //done it
              overlap_result = ASSIGN;
              dest_row = row;
            }
          }
          else if (near_dist > 0
          && near_dist < bottom - row->max_y ()) {
            row_it.backward ();
            dest_row = row_it.data ();
            if (dest_row->min_y () - bottom <=
              (block->line_spacing -
            block->line_size) * tesseract::CCStruct::kDescenderFraction) {
                                 //done it
              overlap_result = ASSIGN;
            }
          }
          else {
            if (top - row->max_y () <=
              (block->line_spacing -
              block->line_size) * (textord_overlap_x +
            tesseract::CCStruct::kAscenderFraction)) {
                                 //done it
              overlap_result = ASSIGN;
              dest_row = row;
            }
          }
        }
      }
      if (overlap_result == ASSIGN)
        dest_row->add_blob (blob_it.extract (), top, bottom,
          block->line_size);
      if (overlap_result == NEW_ROW) {
        if (make_new_rows && top - bottom < block->max_blob_size) {
          dest_row =
            new TO_ROW (blob_it.extract (), top, bottom,
            block->line_size);
          row_count++;
          if (bottom > row_it.data ()->min_y ())
            row_it.add_before_then_move (dest_row);
          //insert in right place
          else
            row_it.add_after_then_move (dest_row);
          smooth_factor =
            1.0 / (row_count * textord_skew_lag +
            textord_skewsmooth_offset);
        }
        else
          overlap_result = REJECT;
      }
    }
    else if (make_new_rows && top - bottom < block->max_blob_size) {
      overlap_result = NEW_ROW;
      dest_row =
        new TO_ROW(blob_it.extract(), top, bottom, block->line_size);
      row_count++;
      row_it.add_after_then_move(dest_row);
      smooth_factor = 1.0 / (row_count * textord_skew_lag +
                             textord_skewsmooth_offset2);
    }
    else
      overlap_result = REJECT;
    if (blob->bounding_box ().contains(testpt) && textord_debug_blob) {
      if (overlap_result != REJECT) {
        tprintf("Test blob assigned to row at (%g,%g) on pass %d\n",
          dest_row->min_y(), dest_row->max_y(), pass);
      }
      else {
        tprintf("Test blob assigned to no row on pass %d\n", pass);
      }
    }
    if (overlap_result != REJECT) {
      while (!row_it.at_first() &&
             row_it.data()->min_y() > row_it.data_relative(-1)->min_y()) {
        row = row_it.extract();
        row_it.backward();
        row_it.add_before_then_move(row);
      }
      while (!row_it.at_last() &&
             row_it.data ()->min_y() < row_it.data_relative (1)->min_y()) {
        row = row_it.extract();
        row_it.forward();
                                 // Keep rows in order.
        row_it.add_after_then_move(row);
      }
      BLOBNBOX_IT added_blob_it(dest_row->blob_list());
      added_blob_it.move_to_last();
      TBOX prev_box = added_blob_it.data_relative(-1)->bounding_box();
      if (dest_row->blob_list()->singleton() ||
          !prev_box.major_x_overlap(blob->bounding_box())) {
        block_skew = (1 - smooth_factor) * block_skew
            + smooth_factor * (blob->bounding_box().bottom() -
            dest_row->initial_min_y());
      }
    }
  }
  for (row_it.mark_cycle_pt(); !row_it.cycled_list(); row_it.forward()) {
    if (row_it.data()->blob_list()->empty())
      delete row_it.extract();  // Discard empty rows.
  }
}

blob_x_order()

int blob_x_order	(	const void *	item1,
		const void *	item2
	)

Definition at line 2575 of file makerow.cpp.

                                    {
                                 //converted ptr
  const BLOBNBOX *blob1 = *reinterpret_cast<const BLOBNBOX* const*>(item1);
                                 //converted ptr
  const BLOBNBOX *blob2 = *reinterpret_cast<const BLOBNBOX* const*>(item2);

  if (blob1->bounding_box ().left () < blob2->bounding_box ().left ())
    return -1;
  else if (blob1->bounding_box ().left () > blob2->bounding_box ().left ())
    return 1;
  else
    return 0;
}

cleanup_rows_making()

void cleanup_rows_making	(	ICOORD	page_tr,
		TO_BLOCK *	block,
		float	gradient,
		FCOORD	rotation,
		int32_t	block_edge,
		bool	testing_on
	)

cleanup_rows_making

Remove overlapping rows and fit all the blobs to what's left.

Definition at line 518 of file makerow.cpp.

  {
                                 //iterators
  BLOBNBOX_IT blob_it = &block->blobs;
  TO_ROW_IT row_it = block->get_rows ();

#ifndef GRAPHICS_DISABLED
  if (textord_show_parallel_rows && testing_on) {
    if (to_win == nullptr)
      create_to_win(page_tr);
  }
#endif
                                 //get row coords
  fit_parallel_rows(block,
                    gradient,
                    rotation,
                    block_edge,
                    textord_show_parallel_rows && testing_on);
  delete_non_dropout_rows(block,
                          gradient,
                          rotation,
                          block_edge,
                          textord_show_parallel_rows && testing_on);
  expand_rows(page_tr, block, gradient, rotation, block_edge, testing_on);
  blob_it.set_to_list (&block->blobs);
  row_it.set_to_list (block->get_rows ());
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ())
    blob_it.add_list_after (row_it.data ()->blob_list ());
  //give blobs back
  assign_blobs_to_rows (block, &gradient, 1, FALSE, FALSE, FALSE);
  //now new rows must be genuine
  blob_it.set_to_list (&block->blobs);
  blob_it.add_list_after (&block->large_blobs);
  assign_blobs_to_rows (block, &gradient, 2, TRUE, TRUE, FALSE);
  //safe to use big ones now
  blob_it.set_to_list (&block->blobs);
                                 //throw all blobs in
  blob_it.add_list_after (&block->noise_blobs);
  blob_it.add_list_after (&block->small_blobs);
  assign_blobs_to_rows (block, &gradient, 3, FALSE, FALSE, FALSE);
}

compute_dropout_distances()

void compute_dropout_distances	(	int32_t *	occupation,
		int32_t *	thresholds,
		int32_t	line_count
	)

Definition at line 904 of file makerow.cpp.

                                {
  int32_t line_index;              //of thresholds line
  int32_t distance;                //from prev dropout
  int32_t next_dist;               //to next dropout
  int32_t back_index;              //for back filling
  int32_t prev_threshold;          //before overwrite

  distance = -line_count;
  line_index = 0;
  do {
    do {
      distance--;
      prev_threshold = thresholds[line_index];
                                 //distance from prev
      thresholds[line_index] = distance;
      line_index++;
    }
    while (line_index < line_count
      && (occupation[line_index] < thresholds[line_index]
      || occupation[line_index - 1] >= prev_threshold));
    if (line_index < line_count) {
      back_index = line_index - 1;
      next_dist = 1;
      while (next_dist < -distance && back_index >= 0) {
        thresholds[back_index] = next_dist;
        back_index--;
        next_dist++;
        distance++;
      }
      distance = 1;
    }
  }
  while (line_index < line_count);
}

compute_height_modes()

int32_t compute_height_modes	(	STATS *	heights,
		int32_t	min_height,
		int32_t	max_height,
		int32_t *	modes,
		int32_t	maxmodes
	)

Definition at line 1625 of file makerow.cpp.

                                             {  // size of modes
  int32_t pile_count;              // no in source pile
  int32_t src_count;               // no of source entries
  int32_t src_index;               // current entry
  int32_t least_count;             // height of smalllest
  int32_t least_index;             // index of least
  int32_t dest_count;              // index in modes

  src_count = max_height + 1 - min_height;
  dest_count = 0;
  least_count = INT32_MAX;
  least_index = -1;
  for (src_index = 0; src_index < src_count; src_index++) {
    pile_count = heights->pile_count(min_height + src_index);
    if (pile_count > 0) {
      if (dest_count < maxmodes) {
        if (pile_count < least_count) {
          // find smallest in array
          least_count = pile_count;
          least_index = dest_count;
        }
        modes[dest_count++] = min_height + src_index;
      } else if (pile_count >= least_count) {
        while (least_index < maxmodes - 1) {
          modes[least_index] = modes[least_index + 1];
          // shuffle up
          least_index++;
        }
        // new one on end
        modes[maxmodes - 1] = min_height + src_index;
        if (pile_count == least_count) {
          // new smallest
          least_index = maxmodes - 1;
        } else {
          least_count = heights->pile_count(modes[0]);
          least_index = 0;
          for (dest_count = 1; dest_count < maxmodes; dest_count++) {
            pile_count = heights->pile_count(modes[dest_count]);
            if (pile_count < least_count) {
              // find smallest
              least_count = pile_count;
              least_index = dest_count;
            }
          }
        }
      }
    }
  }
  return dest_count;
}

compute_line_occupation()

void compute_line_occupation	(	TO_BLOCK *	block,
		float	gradient,
		int32_t	min_y,
		int32_t	max_y,
		int32_t *	occupation,
		int32_t *	deltas
	)

Definition at line 770 of file makerow.cpp.

                              {
  int32_t line_count;              //maxy-miny+1
  int32_t line_index;              //of scan line
  int index;                     //array index for daft compilers
  TO_ROW *row;                   //current row
  TO_ROW_IT row_it = block->get_rows ();
  BLOBNBOX *blob;                //current blob
  BLOBNBOX_IT blob_it;           //iterator
  float length;                  //of skew vector
  TBOX blob_box;                  //bounding box
  FCOORD rotation;               //inverse of skew

  line_count = max_y - min_y + 1;
  length = sqrt (gradient * gradient + 1);
  rotation = FCOORD (1 / length, -gradient / length);
  for (line_index = 0; line_index < line_count; line_index++)
    deltas[line_index] = 0;
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
    row = row_it.data ();
    blob_it.set_to_list (row->blob_list ());
    for (blob_it.mark_cycle_pt (); !blob_it.cycled_list ();
    blob_it.forward ()) {
      blob = blob_it.data ();
      blob_box = blob->bounding_box ();
      blob_box.rotate (rotation);//de-skew it
      int32_t width = blob_box.right() - blob_box.left();
      index = blob_box.bottom() - min_y;
      ASSERT_HOST(index >= 0 && index < line_count);
      // count transitions
      deltas[index] += width;
      index = blob_box.top() - min_y;
      ASSERT_HOST(index >= 0 && index < line_count);
      deltas[index] -= width;
    }
  }
  occupation[0] = deltas[0];
  for (line_index = 1; line_index < line_count; line_index++)
    occupation[line_index] = occupation[line_index - 1] + deltas[line_index];
}

compute_occupation_threshold()

void compute_occupation_threshold	(	int32_t	low_window,
		int32_t	high_window,
		int32_t	line_count,
		int32_t *	occupation,
		int32_t *	thresholds
	)

compute_occupation_threshold

Compute thresholds for textline or not for the occupation array.

Definition at line 823 of file makerow.cpp.

                                   {
  int32_t line_index;              //of thresholds line
  int32_t low_index;               //in occupation
  int32_t high_index;              //in occupation
  int32_t sum;                     //current average
  int32_t divisor;                 //to get thresholds
  int32_t min_index;               //of min occ
  int32_t min_occ;                 //min in locality
  int32_t test_index;              //for finding min

  divisor =
    (int32_t) ceil ((low_window + high_window) / textord_occupancy_threshold);
  if (low_window + high_window < line_count) {
    for (sum = 0, high_index = 0; high_index < low_window; high_index++)
      sum += occupation[high_index];
    for (low_index = 0; low_index < high_window; low_index++, high_index++)
      sum += occupation[high_index];
    min_occ = occupation[0];
    min_index = 0;
    for (test_index = 1; test_index < high_index; test_index++) {
      if (occupation[test_index] <= min_occ) {
        min_occ = occupation[test_index];
        min_index = test_index;  //find min in region
      }
    }
    for (line_index = 0; line_index < low_window; line_index++)
      thresholds[line_index] = (sum - min_occ) / divisor + min_occ;
    //same out to end
    for (low_index = 0; high_index < line_count; low_index++, high_index++) {
      sum -= occupation[low_index];
      sum += occupation[high_index];
      if (occupation[high_index] <= min_occ) {
                                 //find min in region
        min_occ = occupation[high_index];
        min_index = high_index;
      }
                                 //lost min from region
      if (min_index <= low_index) {
        min_occ = occupation[low_index + 1];
        min_index = low_index + 1;
        for (test_index = low_index + 2; test_index <= high_index;
        test_index++) {
          if (occupation[test_index] <= min_occ) {
            min_occ = occupation[test_index];
                                 //find min in region
            min_index = test_index;
          }
        }
      }
      thresholds[line_index++] = (sum - min_occ) / divisor + min_occ;
    }
  }
  else {
    min_occ = occupation[0];
    min_index = 0;
    for (sum = 0, low_index = 0; low_index < line_count; low_index++) {
      if (occupation[low_index] < min_occ) {
        min_occ = occupation[low_index];
        min_index = low_index;
      }
      sum += occupation[low_index];
    }
    line_index = 0;
  }
  for (; line_index < line_count; line_index++)
    thresholds[line_index] = (sum - min_occ) / divisor + min_occ;
  //same out to end
}

compute_page_skew()

void compute_page_skew	(	TO_BLOCK_LIST *	blocks,
		float &	page_m,
		float &	page_err
	)

Definition at line 287 of file makerow.cpp.

                        {
  int32_t row_count;             //total rows
  int32_t blob_count;            //total_blobs
  int32_t row_err;               //integer error
  int32_t row_index;             //of total
  TO_ROW *row;                   //current row
  TO_BLOCK_IT block_it = blocks; //iterator

  row_count = 0;
  blob_count = 0;
  for (block_it.mark_cycle_pt (); !block_it.cycled_list ();
       block_it.forward ()) {
    POLY_BLOCK* pb = block_it.data()->block->pdblk.poly_block();
    if (pb != nullptr && !pb->IsText())
      continue;  // Pretend non-text blocks don't exist.
    row_count += block_it.data ()->get_rows ()->length ();
    //count up rows
    TO_ROW_IT row_it(block_it.data()->get_rows());
    for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ())
      blob_count += row_it.data ()->blob_list ()->length ();
  }
  if (row_count == 0) {
    page_m = 0.0f;
    page_err = 0.0f;
    return;
  }
  // of rows
  std::vector<float> gradients(blob_count);
  // of rows
  std::vector<float> errors(blob_count);

  row_index = 0;
  for (block_it.mark_cycle_pt (); !block_it.cycled_list ();
       block_it.forward ()) {
    POLY_BLOCK* pb = block_it.data()->block->pdblk.poly_block();
    if (pb != nullptr && !pb->IsText())
      continue;  // Pretend non-text blocks don't exist.
    TO_ROW_IT row_it(block_it.data ()->get_rows());
    for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
      row = row_it.data ();
      blob_count = row->blob_list ()->length ();
      row_err = (int32_t) ceil (row->line_error ());
      if (row_err <= 0)
        row_err = 1;
      if (textord_biased_skewcalc) {
        blob_count /= row_err;
        for (blob_count /= row_err; blob_count > 0; blob_count--) {
          gradients[row_index] = row->line_m ();
          errors[row_index] = row->line_error ();
          row_index++;
        }
      }
      else if (blob_count >= textord_min_blobs_in_row) {
                                 //get gradient
        gradients[row_index] = row->line_m ();
        errors[row_index] = row->line_error ();
        row_index++;
      }
    }
  }
  if (row_index == 0) {
                                 //desperate
    for (block_it.mark_cycle_pt (); !block_it.cycled_list ();
         block_it.forward ()) {
      POLY_BLOCK* pb = block_it.data()->block->pdblk.poly_block();
      if (pb != nullptr && !pb->IsText())
        continue;  // Pretend non-text blocks don't exist.
      TO_ROW_IT row_it(block_it.data()->get_rows());
      for (row_it.mark_cycle_pt (); !row_it.cycled_list ();
           row_it.forward ()) {
        row = row_it.data ();
        gradients[row_index] = row->line_m ();
        errors[row_index] = row->line_error ();
        row_index++;
      }
    }
  }
  row_count = row_index;
  row_index = choose_nth_item ((int32_t) (row_count * textord_skew_ile),
    &gradients[0], row_count);
  page_m = gradients[row_index];
  row_index = choose_nth_item ((int32_t) (row_count * textord_skew_ile),
    &errors[0], row_count);
  page_err = errors[row_index];
}

compute_row_descdrop()

int32_t compute_row_descdrop	(	TO_ROW *	row,
		float	gradient,
		int	xheight_blob_count,
		STATS *	heights
	)

Definition at line 1565 of file makerow.cpp.

                                                                       {
  // Count how many potential ascenders are in this row.
  int i_min = asc_heights->min_bucket();
  if ((i_min / row->xheight) < textord_ascx_ratio_min) {
    i_min = static_cast<int>(
        floor(row->xheight * textord_ascx_ratio_min + 0.5));
  }
  int i_max = asc_heights->max_bucket();
  if ((i_max / row->xheight) > textord_ascx_ratio_max) {
    i_max = static_cast<int>(floor(row->xheight * textord_ascx_ratio_max));
  }
  int num_potential_asc = 0;
  for (int i = i_min; i <= i_max; ++i) {
    num_potential_asc += asc_heights->pile_count(i);
  }
  int32_t min_height =
    static_cast<int32_t>(floor(row->xheight * textord_descx_ratio_min + 0.5));
  int32_t max_height =
    static_cast<int32_t>(floor(row->xheight * textord_descx_ratio_max));
  float xcentre;                 // centre of blob
  float height;                  // height of blob
  BLOBNBOX_IT blob_it = row->blob_list();
  BLOBNBOX *blob;                // current blob
  STATS heights (min_height, max_height + 1);
  for (blob_it.mark_cycle_pt(); !blob_it.cycled_list(); blob_it.forward()) {
    blob = blob_it.data();
    if (!blob->joined_to_prev()) {
      xcentre = (blob->bounding_box().left() +
                 blob->bounding_box().right()) / 2.0f;
      height = (gradient * xcentre + row->parallel_c() -
                blob->bounding_box().bottom());
      if (height >= min_height && height <= max_height)
        heights.add(static_cast<int>(floor(height + 0.5)), 1);
    }
  }
  int blob_index = heights.mode();  // find mode
  int blob_count = heights.pile_count(blob_index);  // get count of mode
  float total_fraction =
    (textord_descheight_mode_fraction + textord_ascheight_mode_fraction);
  if (static_cast<float>(blob_count + num_potential_asc) <
      xheight_blob_count * total_fraction) {
    blob_count = 0;
  }
  int descdrop = blob_count > 0 ? -blob_index : 0;
  if (textord_debug_xheights) {
    tprintf("Descdrop: %d (potential ascenders %d, descenders %d)\n",
            descdrop, num_potential_asc, blob_count);
    heights.print();
  }
  return descdrop;
}

compute_row_stats()

void compute_row_stats	(	TO_BLOCK *	block,
		bool	testing_on
	)

Definition at line 1145 of file makerow.cpp.

  {
  int32_t row_index;               //of median
  TO_ROW *row;                   //current row
  TO_ROW *prev_row;              //previous row
  float iqr;                     //inter quartile range
  TO_ROW_IT row_it = block->get_rows ();
                                 //number of rows
  int16_t rowcount = row_it.length ();
  // for choose nth
  std::vector<TO_ROW*> rows(rowcount);
  rowcount = 0;
  prev_row = nullptr;
  row_it.move_to_last ();        //start at bottom
  do {
    row = row_it.data ();
    if (prev_row != nullptr) {
      rows[rowcount++] = prev_row;
      prev_row->spacing = row->intercept () - prev_row->intercept ();
      if (testing_on)
        tprintf ("Row at %g yields spacing of %g\n",
          row->intercept (), prev_row->spacing);
    }
    prev_row = row;
    row_it.backward ();
  }
  while (!row_it.at_last ());
  block->key_row = prev_row;
  block->baseline_offset =
    fmod (prev_row->parallel_c (), block->line_spacing);
  if (testing_on)
    tprintf ("Blob based spacing=(%g,%g), offset=%g",
      block->line_size, block->line_spacing, block->baseline_offset);
  if (rowcount > 0) {
    row_index = choose_nth_item(rowcount * 3 / 4, &rows[0], rowcount,
      sizeof (TO_ROW *), row_spacing_order);
    iqr = rows[row_index]->spacing;
    row_index = choose_nth_item(rowcount / 4, &rows[0], rowcount,
      sizeof (TO_ROW *), row_spacing_order);
    iqr -= rows[row_index]->spacing;
    row_index = choose_nth_item(rowcount / 2, &rows[0], rowcount,
      sizeof (TO_ROW *), row_spacing_order);
    block->key_row = rows[row_index];
    if (testing_on)
      tprintf (" row based=%g(%g)", rows[row_index]->spacing, iqr);
    if (rowcount > 2
    && iqr < rows[row_index]->spacing * textord_linespace_iqrlimit) {
      if (!textord_new_initial_xheight) {
        if (rows[row_index]->spacing < block->line_spacing
          && rows[row_index]->spacing > block->line_size)
          //within range
          block->line_size = rows[row_index]->spacing;
        //spacing=size
        else if (rows[row_index]->spacing > block->line_spacing)
          block->line_size = block->line_spacing;
        //too big so use max
      }
      else {
        if (rows[row_index]->spacing < block->line_spacing)
          block->line_size = rows[row_index]->spacing;
        else
          block->line_size = block->line_spacing;
        //too big so use max
      }
      if (block->line_size < textord_min_xheight)
        block->line_size = (float) textord_min_xheight;
      block->line_spacing = rows[row_index]->spacing;
      block->max_blob_size =
        block->line_spacing * textord_excess_blobsize;
    }
    block->baseline_offset = fmod (rows[row_index]->intercept (),
      block->line_spacing);
  }
  if (testing_on)
    tprintf ("\nEstimate line size=%g, spacing=%g, offset=%g\n",
      block->line_size, block->line_spacing, block->baseline_offset);
}

compute_xheight_from_modes()

int compute_xheight_from_modes	(	STATS *	heights,
		STATS *	floating_heights,
		bool	cap_only,
		int	min_height,
		int	max_height,
		float *	xheight,
		float *	ascrise
	)

Definition at line 1469 of file makerow.cpp.

                                                    {
  int blob_index = heights->mode();  // find mode
  int blob_count = heights->pile_count(blob_index);  // get count of mode
  if (textord_debug_xheights) {
    tprintf("min_height=%d, max_height=%d, mode=%d, count=%d, total=%d\n",
            min_height, max_height, blob_index, blob_count,
            heights->get_total());
    heights->print();
    floating_heights->print();
  }
  if (blob_count == 0) return 0;
  int modes[MAX_HEIGHT_MODES];  // biggest piles
  bool in_best_pile = FALSE;
  int prev_size = -INT32_MAX;
  int best_count = 0;
  int mode_count = compute_height_modes(heights, min_height, max_height,
                                        modes, MAX_HEIGHT_MODES);
  if (cap_only && mode_count > 1)
    mode_count = 1;
  int x;
  if (textord_debug_xheights) {
    tprintf("found %d modes: ", mode_count);
    for (x = 0; x < mode_count; x++) tprintf("%d ", modes[x]);
    tprintf("\n");
  }

  for (x = 0; x < mode_count - 1; x++) {
    if (modes[x] != prev_size + 1)
      in_best_pile = FALSE;    // had empty height
    int modes_x_count = heights->pile_count(modes[x]) -
      floating_heights->pile_count(modes[x]);
    if ((modes_x_count >= blob_count * textord_xheight_mode_fraction) &&
        (in_best_pile || modes_x_count > best_count)) {
      for (int asc = x + 1; asc < mode_count; asc++) {
        float ratio =
          static_cast<float>(modes[asc]) / static_cast<float>(modes[x]);
        if (textord_ascx_ratio_min < ratio &&
            ratio < textord_ascx_ratio_max &&
            (heights->pile_count(modes[asc]) >=
             blob_count * textord_ascheight_mode_fraction)) {
          if (modes_x_count > best_count) {
            in_best_pile = true;
            best_count = modes_x_count;
          }
          if (textord_debug_xheights) {
            tprintf("X=%d, asc=%d, count=%d, ratio=%g\n",
                    modes[x], modes[asc]-modes[x], modes_x_count, ratio);
          }
          prev_size = modes[x];
          *xheight = static_cast<float>(modes[x]);
          *ascrise = static_cast<float>(modes[asc] - modes[x]);
        }
      }
    }
  }
  if (*xheight == 0) {  // single mode
    // Remove counts of the "floating" blobs (the one whose height is too
    // small in relation to it's top end of the bounding box) from heights
    // before computing the single-mode xheight.
    // Restore the counts in heights after the mode is found, since
    // floating blobs might be useful for determining potential ascenders
    // in compute_row_descdrop().
    if (floating_heights->get_total() > 0) {
      for (x = min_height; x < max_height; ++x) {
        heights->add(x, -(floating_heights->pile_count(x)));
      }
      blob_index = heights->mode();  // find the modified mode
      for (x = min_height; x < max_height; ++x) {
        heights->add(x, floating_heights->pile_count(x));
      }
    }
    *xheight = static_cast<float>(blob_index);
    *ascrise = 0.0f;
    best_count = heights->pile_count(blob_index);
    if (textord_debug_xheights)
      tprintf("Single mode xheight set to %g\n", *xheight);
  } else if (textord_debug_xheights) {
    tprintf("Multi-mode xheight set to %g, asc=%g\n", *xheight, *ascrise);
  }
  return best_count;
}

correct_row_xheight()

void correct_row_xheight	(	TO_ROW *	row,
		float	xheight,
		float	ascrise,
		float	descdrop
	)

Definition at line 1687 of file makerow.cpp.

                                                        {
  ROW_CATEGORY row_category = get_row_category(row);
  if (textord_debug_xheights) {
    tprintf("correcting row xheight: row->xheight %.4f"
            ", row->acrise %.4f row->descdrop %.4f\n",
            row->xheight, row->ascrise, row->descdrop);
  }
  bool normal_xheight =
    within_error_margin(row->xheight, xheight, textord_xheight_error_margin);
  bool cap_xheight =
    within_error_margin(row->xheight, xheight + ascrise,
                        textord_xheight_error_margin);
  // Use the average xheight/ascrise for the following cases:
  // -- the xheight of the row could not be determined at all
  // -- the row has descenders (e.g. "many groups", "ISBN 12345 p.3")
  //    and its xheight is close to either cap height or average xheight
  // -- the row does not have ascenders or descenders, but its xheight
  //    is close to the average block xheight (e.g. row with "www.mmm.com")
  if (row_category == ROW_ASCENDERS_FOUND) {
    if (row->descdrop >= 0.0) {
      row->descdrop = row->xheight * (descdrop / xheight);
    }
  } else if (row_category == ROW_INVALID ||
             (row_category == ROW_DESCENDERS_FOUND &&
              (normal_xheight || cap_xheight)) ||
              (row_category == ROW_UNKNOWN && normal_xheight)) {
    if (textord_debug_xheights) tprintf("using average xheight\n");
    row->xheight = xheight;
    row->ascrise = ascrise;
    row->descdrop = descdrop;
  } else if (row_category == ROW_DESCENDERS_FOUND) {
    // Assume this is a row with mostly lowercase letters and it's xheight
    // is computed correctly (unfortunately there is no way to distinguish
    // this from the case when descenders are found, but the most common
    // height is capheight).
    if (textord_debug_xheights) tprintf("lowercase, corrected ascrise\n");
    row->ascrise = row->xheight * (ascrise / xheight);
  } else if (row_category == ROW_UNKNOWN) {
  // Otherwise assume this row is an all-caps or small-caps row
  // and adjust xheight and ascrise of the row.

    row->all_caps = true;
    if (cap_xheight) { // regular all caps
      if (textord_debug_xheights) tprintf("all caps\n");
      row->xheight = xheight;
      row->ascrise = ascrise;
      row->descdrop = descdrop;
    } else {  // small caps or caps with an odd xheight
      if (textord_debug_xheights) {
        if (row->xheight < xheight + ascrise && row->xheight > xheight) {
          tprintf("small caps\n");
        } else {
          tprintf("all caps with irregular xheight\n");
        }
      }
      row->ascrise = row->xheight * (ascrise / (xheight + ascrise));
      row->xheight -= row->ascrise;
      row->descdrop = row->xheight * (descdrop / xheight);
    }
  }
  if (textord_debug_xheights) {
    tprintf("corrected row->xheight = %.4f, row->acrise = %.4f, row->descdrop"
            " = %.4f\n", row->xheight, row->ascrise, row->descdrop);
  }
}

delete_non_dropout_rows()

void delete_non_dropout_rows	(	TO_BLOCK *	block,
		float	gradient,
		FCOORD	rotation,
		int32_t	block_edge,
		bool	testing_on
	)

delete_non_dropout_rows

Compute the linespacing and offset.

Definition at line 571 of file makerow.cpp.

  {
  TBOX block_box;                 //deskewed block
  int32_t max_y;                   //in block
  int32_t min_y;
  int32_t line_index;              //of scan line
  int32_t line_count;              //no of scan lines
  int32_t distance;                //to drop-out
  int32_t xleft;                   //of block
  int32_t ybottom;                 //of block
  TO_ROW *row;                   //current row
  TO_ROW_IT row_it = block->get_rows ();
  BLOBNBOX_IT blob_it = &block->blobs;

  if (row_it.length () == 0)
    return;                      //empty block
  block_box = deskew_block_coords (block, gradient);
  xleft = block->block->pdblk.bounding_box ().left ();
  ybottom = block->block->pdblk.bounding_box ().bottom ();
  min_y = block_box.bottom () - 1;
  max_y = block_box.top () + 1;
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
    line_index = (int32_t) floor (row_it.data ()->intercept ());
    if (line_index <= min_y)
      min_y = line_index - 1;
    if (line_index >= max_y)
      max_y = line_index + 1;
  }
  line_count = max_y - min_y + 1;
  if (line_count <= 0)
    return;                      //empty block
  // change in occupation
  std::vector<int32_t> deltas(line_count);
  // of pixel coords
  std::vector<int32_t> occupation(line_count);

  compute_line_occupation(block, gradient, min_y, max_y, &occupation[0], &deltas[0]);
  compute_occupation_threshold ((int32_t)
    ceil (block->line_spacing *
    (tesseract::CCStruct::kDescenderFraction +
    tesseract::CCStruct::kAscenderFraction)),
    (int32_t) ceil (block->line_spacing *
    (tesseract::CCStruct::kXHeightFraction +
    tesseract::CCStruct::kAscenderFraction)),
    max_y - min_y + 1, &occupation[0], &deltas[0]);
#ifndef GRAPHICS_DISABLED
  if (testing_on) {
    draw_occupation(xleft, ybottom, min_y, max_y, &occupation[0], &deltas[0]);
  }
#endif
  compute_dropout_distances(&occupation[0], &deltas[0], line_count);
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
    row = row_it.data ();
    line_index = (int32_t) floor (row->intercept ());
    distance = deltas[line_index - min_y];
    if (find_best_dropout_row (row, distance, block->line_spacing / 2,
    line_index, &row_it, testing_on)) {
#ifndef GRAPHICS_DISABLED
      if (testing_on)
        plot_parallel_row(row, gradient, block_edge,
                          ScrollView::WHITE, rotation);
#endif
      blob_it.add_list_after (row_it.data ()->blob_list ());
      delete row_it.extract ();  //too far away
    }
  }
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
    blob_it.add_list_after (row_it.data ()->blob_list ());
  }
}

deskew_block_coords()

TBOX deskew_block_coords	(	TO_BLOCK *	block,
		float	gradient
	)

Definition at line 734 of file makerow.cpp.

                         {
  TBOX result;                    //block bounds
  TBOX blob_box;                  //of block
  FCOORD rotation;               //deskew vector
  float length;                  //of gradient vector
  TO_ROW_IT row_it = block->get_rows ();
  TO_ROW *row;                   //current row
  BLOBNBOX *blob;                //current blob
  BLOBNBOX_IT blob_it;           //iterator

  length = sqrt (gradient * gradient + 1);
  rotation = FCOORD (1 / length, -gradient / length);
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
    row = row_it.data ();
    blob_it.set_to_list (row->blob_list ());
    for (blob_it.mark_cycle_pt (); !blob_it.cycled_list ();
    blob_it.forward ()) {
      blob = blob_it.data ();
      blob_box = blob->bounding_box ();
      blob_box.rotate (rotation);//de-skew it
      result += blob_box;
    }
  }
  return result;
}

expand_rows()

void expand_rows	(	ICOORD	page_tr,
		TO_BLOCK *	block,
		float	gradient,
		FCOORD	rotation,
		int32_t	block_edge,
		bool	testing_on
	)

Definition at line 951 of file makerow.cpp.

  {
  bool swallowed_row;           //eaten a neighbour
  float y_max, y_min;            //new row limits
  float y_bottom, y_top;         //allowed limits
  TO_ROW *test_row;              //next row
  TO_ROW *row;                   //current row
                                 //iterators
  BLOBNBOX_IT blob_it = &block->blobs;
  TO_ROW_IT row_it = block->get_rows ();

#ifndef GRAPHICS_DISABLED
  if (textord_show_expanded_rows && testing_on) {
    if (to_win == nullptr)
      create_to_win(page_tr);
  }
#endif

  adjust_row_limits(block);  //shift min,max.
  if (textord_new_initial_xheight) {
    if (block->get_rows ()->length () == 0)
      return;
    compute_row_stats(block, textord_show_expanded_rows && testing_on);
  }
  assign_blobs_to_rows (block, &gradient, 4, true, false, false);
  //get real membership
  if (block->get_rows ()->length () == 0)
    return;
  fit_parallel_rows(block,
                    gradient,
                    rotation,
                    block_edge,
                    textord_show_expanded_rows && testing_on);
  if (!textord_new_initial_xheight)
    compute_row_stats(block, textord_show_expanded_rows && testing_on);
  row_it.move_to_last ();
  do {
    row = row_it.data ();
    y_max = row->max_y ();       //get current limits
    y_min = row->min_y ();
    y_bottom = row->intercept () - block->line_size * textord_expansion_factor *
      tesseract::CCStruct::kDescenderFraction;
    y_top = row->intercept () + block->line_size * textord_expansion_factor *
        (tesseract::CCStruct::kXHeightFraction +
         tesseract::CCStruct::kAscenderFraction);
    if (y_min > y_bottom) {      //expansion allowed
      if (textord_show_expanded_rows && testing_on)
        tprintf("Expanding bottom of row at %f from %f to %f\n",
                row->intercept(), y_min, y_bottom);
                                 //expandable
      swallowed_row = true;
      while (swallowed_row && !row_it.at_last ()) {
        swallowed_row = false;
                                 //get next one
        test_row = row_it.data_relative (1);
                                 //overlaps space
        if (test_row->max_y () > y_bottom) {
          if (test_row->min_y () > y_bottom) {
            if (textord_show_expanded_rows && testing_on)
              tprintf("Eating row below at %f\n", test_row->intercept());
            row_it.forward ();
#ifndef GRAPHICS_DISABLED
            if (textord_show_expanded_rows && testing_on)
              plot_parallel_row(test_row,
                                gradient,
                                block_edge,
                                ScrollView::WHITE,
                                rotation);
#endif
            blob_it.set_to_list (row->blob_list ());
            blob_it.add_list_after (test_row->blob_list ());
                                 //swallow complete row
            delete row_it.extract ();
            row_it.backward ();
            swallowed_row = true;
          }
          else if (test_row->max_y () < y_min) {
                                 //shorter limit
            y_bottom = test_row->max_y ();
            if (textord_show_expanded_rows && testing_on)
              tprintf("Truncating limit to %f due to touching row at %f\n",
                      y_bottom, test_row->intercept());
          }
          else {
            y_bottom = y_min;    //can't expand it
            if (textord_show_expanded_rows && testing_on)
              tprintf("Not expanding limit beyond %f due to touching row at %f\n",
                      y_bottom, test_row->intercept());
          }
        }
      }
      y_min = y_bottom;          //expand it
    }
    if (y_max < y_top) {         //expansion allowed
      if (textord_show_expanded_rows && testing_on)
        tprintf("Expanding top of row at %f from %f to %f\n",
                row->intercept(), y_max, y_top);
      swallowed_row = true;
      while (swallowed_row && !row_it.at_first ()) {
        swallowed_row = false;
                                 //get one above
        test_row = row_it.data_relative (-1);
        if (test_row->min_y () < y_top) {
          if (test_row->max_y () < y_top) {
            if (textord_show_expanded_rows && testing_on)
              tprintf("Eating row above at %f\n", test_row->intercept());
            row_it.backward ();
            blob_it.set_to_list (row->blob_list ());
#ifndef GRAPHICS_DISABLED
            if (textord_show_expanded_rows && testing_on)
              plot_parallel_row(test_row,
                                gradient,
                                block_edge,
                                ScrollView::WHITE,
                                rotation);
#endif
            blob_it.add_list_after (test_row->blob_list ());
                                 //swallow complete row
            delete row_it.extract ();
            row_it.forward ();
            swallowed_row = true;
          }
          else if (test_row->min_y () < y_max) {
                                 //shorter limit
            y_top = test_row->min_y ();
            if (textord_show_expanded_rows && testing_on)
              tprintf("Truncating limit to %f due to touching row at %f\n",
                      y_top, test_row->intercept());
          }
          else {
            y_top = y_max;       //can't expand it
            if (textord_show_expanded_rows && testing_on)
              tprintf("Not expanding limit beyond %f due to touching row at %f\n",
                      y_top, test_row->intercept());
          }
        }
      }
      y_max = y_top;
    }
                                 //new limits
    row->set_limits (y_min, y_max);
    row_it.backward ();
  }
  while (!row_it.at_last ());
}

fill_heights()

void fill_heights	(	TO_ROW *	row,
		float	gradient,
		int	min_height,
		int	max_height,
		STATS *	heights,
		STATS *	floating_heights
	)

Definition at line 1408 of file makerow.cpp.

                                                                           {
  float xcentre;                 // centre of blob
  float top;                     // top y coord of blob
  float height;                  // height of blob
  BLOBNBOX *blob;                // current blob
  int repeated_set;
  BLOBNBOX_IT blob_it = row->blob_list();
  if (blob_it.empty()) return;  // no blobs in this row
  bool has_rep_chars =
    row->rep_chars_marked() && row->num_repeated_sets() > 0;
  do {
    blob = blob_it.data();
    if (!blob->joined_to_prev()) {
      xcentre = (blob->bounding_box().left() +
                 blob->bounding_box().right()) / 2.0f;
      top = blob->bounding_box().top();
      height = blob->bounding_box().height();
      if (textord_fix_xheight_bug)
        top -= row->baseline.y(xcentre);
      else
        top -= gradient * xcentre + row->parallel_c();
      if (top >= min_height && top <= max_height) {
        heights->add(static_cast<int32_t>(floor(top + 0.5)), 1);
        if (height / top < textord_min_blob_height_fraction) {
          floating_heights->add(static_cast<int32_t>(floor(top + 0.5)), 1);
        }
      }
    }
    // Skip repeated chars, since they are likely to skew the height stats.
    if (has_rep_chars && blob->repeated_set() != 0) {
      repeated_set = blob->repeated_set();
      blob_it.forward();
      while (!blob_it.at_first() &&
             blob_it.data()->repeated_set() == repeated_set) {
        blob_it.forward();
        if (textord_debug_xheights)
          tprintf("Skipping repeated char when computing xheight\n");
      }
    } else {
      blob_it.forward();
    }
  } while (!blob_it.at_first());
}

find_best_dropout_row()

bool find_best_dropout_row	(	TO_ROW *	row,
		int32_t	distance,
		float	dist_limit,
		int32_t	line_index,
		TO_ROW_IT *	row_it,
		bool	testing_on
	)

Definition at line 654 of file makerow.cpp.

  {
  int32_t next_index;              // of neighbouring row
  int32_t row_offset;              //from current row
  int32_t abs_dist;                //absolute distance
  int8_t row_inc;                  //increment to row_index
  TO_ROW *next_row;              //nextious row

  if (testing_on)
    tprintf ("Row at %g(%g), dropout dist=%d,",
      row->intercept (), row->parallel_c (), distance);
  if (distance < 0) {
    row_inc = 1;
    abs_dist = -distance;
  }
  else {
    row_inc = -1;
    abs_dist = distance;
  }
  if (abs_dist > dist_limit) {
    if (testing_on) {
      tprintf (" too far - deleting\n");
    }
    return true;
  }
  if ((distance < 0 && !row_it->at_last ())
  || (distance >= 0 && !row_it->at_first ())) {
    row_offset = row_inc;
    do {
      next_row = row_it->data_relative (row_offset);
      next_index = (int32_t) floor (next_row->intercept ());
      if ((distance < 0
        && next_index < line_index
        && next_index > line_index + distance + distance)
        || (distance >= 0
        && next_index > line_index
      && next_index < line_index + distance + distance)) {
        if (testing_on) {
          tprintf (" nearer neighbour (%d) at %g\n",
            line_index + distance - next_index,
            next_row->intercept ());
        }
        return true;             //other is nearer
      }
      else if (next_index == line_index
      || next_index == line_index + distance + distance) {
        if (row->believability () <= next_row->believability ()) {
          if (testing_on) {
            tprintf (" equal but more believable at %g (%g/%g)\n",
              next_row->intercept (),
              row->believability (),
              next_row->believability ());
          }
          return true;           //other is more believable
        }
      }
      row_offset += row_inc;
    }
    while ((next_index == line_index
      || next_index == line_index + distance + distance)
      && row_offset < row_it->length ());
    if (testing_on)
      tprintf (" keeping\n");
  }
  return false;
}

fit_lms_line()

void fit_lms_line

(

TO_ROW *

row

)

Definition at line 267 of file makerow.cpp.

                               {
  float m, c;                    // fitted line
  tesseract::DetLineFit lms;
  BLOBNBOX_IT blob_it = row->blob_list();

  for (blob_it.mark_cycle_pt(); !blob_it.cycled_list(); blob_it.forward()) {
    const TBOX& box = blob_it.data()->bounding_box();
    lms.Add(ICOORD((box.left() + box.right()) / 2, box.bottom()));
  }
  double error = lms.Fit(&m, &c);
  row->set_line(m, c, error);
}

fit_parallel_lms()

void fit_parallel_lms	(	float	gradient,
		TO_ROW *	row
	)

Definition at line 1975 of file makerow.cpp.

                                                   {
  float c;                       // fitted line
  int blobcount;                 // no of blobs
   tesseract::DetLineFit lms;
  BLOBNBOX_IT blob_it = row->blob_list();

  blobcount = 0;
  for (blob_it.mark_cycle_pt(); !blob_it.cycled_list(); blob_it.forward()) {
    if (!blob_it.data()->joined_to_prev()) {
      const TBOX& box = blob_it.data()->bounding_box();
      lms.Add(ICOORD((box.left() + box.right()) / 2, box.bottom()));
      blobcount++;
    }
  }
  double error = lms.ConstrainedFit(gradient, &c);
  row->set_parallel_line(gradient, c, error);
  if (textord_straight_baselines && blobcount > textord_lms_line_trials) {
    error = lms.Fit(&gradient, &c);
  }
                                 //set the other too
  row->set_line(gradient, c, error);
}

fit_parallel_rows()

void fit_parallel_rows	(	TO_BLOCK *	block,
		float	gradient,
		FCOORD	rotation,
		int32_t	block_edge,
		bool	testing_on
	)

Definition at line 1933 of file makerow.cpp.

  {
#ifndef GRAPHICS_DISABLED
  ScrollView::Color colour;                 //of row
#endif
  TO_ROW_IT row_it = block->get_rows ();

  row_it.move_to_first ();
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
    if (row_it.data ()->blob_list ()->empty ())
      delete row_it.extract ();  //nothing in it
    else
      fit_parallel_lms (gradient, row_it.data ());
  }
#ifndef GRAPHICS_DISABLED
  if (testing_on) {
    colour = ScrollView::RED;
    for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
      plot_parallel_row (row_it.data (), gradient,
        block_edge, colour, rotation);
      colour = (ScrollView::Color) (colour + 1);
      if (colour > ScrollView::MAGENTA)
        colour = ScrollView::RED;
    }
  }
#endif
  row_it.sort (row_y_order);     //may have gone out of order
}

get_min_max_xheight()

void get_min_max_xheight ( int  block_linesize, int *  min_height, int *  max_height  )

inline

Definition at line 115 of file makerow.h.

                                                                  {
  *min_height = static_cast<int32_t>(floor(block_linesize * textord_minxh));
  if (*min_height < textord_min_xheight) *min_height = textord_min_xheight;
  *max_height = static_cast<int32_t>(ceil(block_linesize * 3.0));
}

get_row_category()

ROW_CATEGORY get_row_category ( const TO_ROW *  row )

inline

Definition at line 122 of file makerow.h.

                                                        {
  if (row->xheight <= 0) return ROW_INVALID;
  return (row->ascrise > 0) ? ROW_ASCENDERS_FOUND :
    (row->descdrop != 0) ? ROW_DESCENDERS_FOUND : ROW_UNKNOWN;
}

linear_spline_baseline()

double* linear_spline_baseline	(	TO_ROW *	row,
		TO_BLOCK *	block,
		int32_t &	segments,
		int32_t	xstarts[]
	)

Definition at line 2189 of file makerow.cpp.

  {
  int blobcount;                 //no of blobs
  int blobindex;                 //current blob
  int index1, index2;            //blob numbers
  int blobs_per_segment;         //blobs in each
  TBOX box;                      //blob box
  TBOX new_box;                  //new_it box
                                 //blobs
  BLOBNBOX_IT blob_it = row->blob_list ();
  BLOBNBOX_IT new_it = blob_it;  //front end
  float b, c;                    //fitted curve
  tesseract::DetLineFit lms;
  int32_t segment;               //current segment

  box = box_next_pre_chopped (&blob_it);
  xstarts[0] = box.left ();
  blobcount = 1;
  while (!blob_it.at_first ()) {
    blobcount++;
    box = box_next_pre_chopped (&blob_it);
  }
  segments = blobcount / textord_spline_medianwin;
  if (segments < 1)
    segments = 1;
  blobs_per_segment = blobcount / segments;
  // quadratic coeffs
  double *coeffs = new double[segments * 3];
  if (textord_oldbl_debug)
    tprintf
      ("Linear splining baseline of %d blobs at (%d,%d), into %d segments of %d blobs\n",
      blobcount, box.left (), box.bottom (), segments, blobs_per_segment);
  segment = 1;
  for (index2 = 0; index2 < blobs_per_segment / 2; index2++)
    box_next_pre_chopped(&new_it);
  index1 = 0;
  blobindex = index2;
  do {
    blobindex += blobs_per_segment;
    lms.Clear();
    while (index1 < blobindex || (segment == segments && index1 < blobcount)) {
      box = box_next_pre_chopped (&blob_it);
      int middle = (box.left() + box.right()) / 2;
      lms.Add(ICOORD(middle, box.bottom()));
      index1++;
      if (index1 == blobindex - blobs_per_segment / 2
      || index1 == blobcount - 1) {
        xstarts[segment] = box.left ();
      }
    }
    lms.Fit(&b, &c);
    coeffs[segment * 3 - 3] = 0;
    coeffs[segment * 3 - 2] = b;
    coeffs[segment * 3 - 1] = c;
    segment++;
    if (segment > segments)
      break;

    blobindex += blobs_per_segment;
    lms.Clear();
    while (index2 < blobindex || (segment == segments && index2 < blobcount)) {
      new_box = box_next_pre_chopped (&new_it);
      int middle = (new_box.left() + new_box.right()) / 2;
      lms.Add(ICOORD (middle, new_box.bottom()));
      index2++;
      if (index2 == blobindex - blobs_per_segment / 2
      || index2 == blobcount - 1) {
        xstarts[segment] = new_box.left ();
      }
    }
    lms.Fit(&b, &c);
    coeffs[segment * 3 - 3] = 0;
    coeffs[segment * 3 - 2] = b;
    coeffs[segment * 3 - 1] = c;
    segment++;
  }
  while (segment <= segments);
  return coeffs;
}

make_baseline_spline()

void make_baseline_spline	(	TO_ROW *	row,
		TO_BLOCK *	block
	)

Definition at line 2058 of file makerow.cpp.

                                           {
  double *coeffs;                // quadratic coeffs
  int32_t segments;              // no of segments

  // spline boundaries
  int32_t *xstarts = new int32_t[row->blob_list()->length() + 1];
  if (segment_baseline(row, block, segments, xstarts)
  && !textord_straight_baselines && !textord_parallel_baselines) {
    coeffs = linear_spline_baseline(row, block, segments, xstarts);
  } else {
    xstarts[1] = xstarts[segments];
    segments = 1;
    coeffs = new double[3];
    coeffs[0] = 0;
    coeffs[1] = row->line_m ();
    coeffs[2] = row->line_c ();
  }
  row->baseline = QSPLINE (segments, xstarts, coeffs);
  delete[] coeffs;
  delete[] xstarts;
}

make_initial_textrows()

void make_initial_textrows	(	ICOORD	page_tr,
		TO_BLOCK *	block,
		FCOORD	rotation,
		bool	testing_on
	)

Definition at line 227 of file makerow.cpp.

  {
  TO_ROW_IT row_it = block->get_rows ();

#ifndef GRAPHICS_DISABLED
  ScrollView::Color colour;                 //of row

  if (textord_show_initial_rows && testing_on) {
    if (to_win == nullptr)
      create_to_win(page_tr);
  }
#endif
                                 //guess skew
  assign_blobs_to_rows (block, nullptr, 0, TRUE, TRUE, textord_show_initial_rows && testing_on);
  row_it.move_to_first ();
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ())
    fit_lms_line (row_it.data ());
#ifndef GRAPHICS_DISABLED
  if (textord_show_initial_rows && testing_on) {
    colour = ScrollView::RED;
    for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
      plot_to_row (row_it.data (), colour, rotation);
      colour = (ScrollView::Color) (colour + 1);
      if (colour > ScrollView::MAGENTA)
        colour = ScrollView::RED;
    }
  }
#endif
}

make_rows()

float make_rows	(	ICOORD	page_tr,
		TO_BLOCK_LIST *	port_blocks
	)

Definition at line 201 of file makerow.cpp.

                                                            {
  float port_m;                  // global skew
  float port_err;                // global noise
  TO_BLOCK_IT block_it;          // iterator

  block_it.set_to_list(port_blocks);
  for (block_it.mark_cycle_pt(); !block_it.cycled_list();
       block_it.forward())
  make_initial_textrows(page_tr, block_it.data(), FCOORD(1.0f, 0.0f),
      !textord_test_landscape);
                                 // compute globally
  compute_page_skew(port_blocks, port_m, port_err);
  block_it.set_to_list(port_blocks);
  for (block_it.mark_cycle_pt(); !block_it.cycled_list(); block_it.forward()) {
    cleanup_rows_making(page_tr, block_it.data(), port_m, FCOORD(1.0f, 0.0f),
                 block_it.data()->block->pdblk.bounding_box().left(),
                 !textord_test_landscape);
  }
  return port_m;                 // global skew
}

make_single_row()

float make_single_row	(	ICOORD	page_tr,
		bool	allow_sub_blobs,
		TO_BLOCK *	block,
		TO_BLOCK_LIST *	blocks
	)

Definition at line 164 of file makerow.cpp.

                                                              {
  BLOBNBOX_IT blob_it = &block->blobs;
  TO_ROW_IT row_it = block->get_rows();

  // Include all the small blobs and large blobs.
  blob_it.add_list_after(&block->small_blobs);
  blob_it.add_list_after(&block->noise_blobs);
  blob_it.add_list_after(&block->large_blobs);
  if (block->blobs.singleton() && allow_sub_blobs) {
    blob_it.move_to_first();
    float size = MakeRowFromSubBlobs(block, blob_it.data()->cblob(), &row_it);
    if (size > block->line_size)
      block->line_size = size;
  } else if (block->blobs.empty()) {
    // Make a fake blob.
    C_BLOB* blob = C_BLOB::FakeBlob(block->block->pdblk.bounding_box());
    // The blobnbox owns the blob.
    BLOBNBOX* bblob = new BLOBNBOX(blob);
    blob_it.add_after_then_move(bblob);
  }
  MakeRowFromBlobs(block->line_size, &blob_it, &row_it);
  // Fit an LMS line to the rows.
  for (row_it.mark_cycle_pt(); !row_it.cycled_list(); row_it.forward())
    fit_lms_line(row_it.data());
  float gradient;
  float fit_error;
  // Compute the skew based on the fitted line.
  compute_page_skew(blocks, gradient, fit_error);
  return gradient;
}

mark_repeated_chars()

void mark_repeated_chars

(

TO_ROW *

row

)

Definition at line 2641 of file makerow.cpp.

                                      {
  BLOBNBOX_IT box_it(row->blob_list());            // Iterator.
  int num_repeated_sets = 0;
  if (!box_it.empty()) {
    do {
      BLOBNBOX* bblob = box_it.data();
      int repeat_length = 1;
      if (bblob->flow() == BTFT_LEADER &&
          !bblob->joined_to_prev() && bblob->cblob() != nullptr) {
        BLOBNBOX_IT test_it(box_it);
        for (test_it.forward(); !test_it.at_first();) {
          bblob = test_it.data();
          if (bblob->flow() != BTFT_LEADER)
            break;
          test_it.forward();
          bblob = test_it.data();
          if (bblob->joined_to_prev() || bblob->cblob() == nullptr) {
            repeat_length = 0;
            break;
          }
          ++repeat_length;
        }
      }
      if (repeat_length >= kMinLeaderCount) {
        num_repeated_sets++;
        for (; repeat_length > 0; box_it.forward(), --repeat_length) {
          bblob = box_it.data();
          bblob->set_repeated_set(num_repeated_sets);
        }
     } else {
        bblob->set_repeated_set(0);
        box_it.forward();
      }
    } while (!box_it.at_first());  // until all done
  }
  row->set_num_repeated_sets(num_repeated_sets);
}

median_block_xheight()

float median_block_xheight	(	TO_BLOCK *	block,
		float	gradient
	)

most_overlapping_row()

OVERLAP_STATE most_overlapping_row	(	TO_ROW_IT *	row_it,
		TO_ROW *&	best_row,
		float	top,
		float	bottom,
		float	rowsize,
		bool	testing_blob
	)

Definition at line 2480 of file makerow.cpp.

  {
  OVERLAP_STATE result;          //result of tests
  float overlap;                 //of blob & row
  float bestover;                //nearest row
  float merge_top, merge_bottom; //size of merged row
  ICOORD testpt;                 //testing only
  TO_ROW *row;                   //current row
  TO_ROW *test_row;              //for multiple overlaps
  BLOBNBOX_IT blob_it;           //for merging rows

  result = ASSIGN;
  row = row_it->data ();
  bestover = top - bottom;
  if (top > row->max_y ())
    bestover -= top - row->max_y ();
  if (bottom < row->min_y ())
                                 //compute overlap
    bestover -= row->min_y () - bottom;
  if (testing_blob && textord_debug_blob) {
    tprintf("Test blob y=(%g,%g), row=(%f,%f), size=%g, overlap=%f\n",
            bottom, top, row->min_y(), row->max_y(), rowsize, bestover);
  }
  test_row = row;
  do {
    if (!row_it->at_last ()) {
      row_it->forward ();
      test_row = row_it->data ();
      if (test_row->min_y () <= top && test_row->max_y () >= bottom) {
        merge_top =
          test_row->max_y () >
          row->max_y ()? test_row->max_y () : row->max_y ();
        merge_bottom =
          test_row->min_y () <
          row->min_y ()? test_row->min_y () : row->min_y ();
        if (merge_top - merge_bottom <= rowsize) {
          if (testing_blob && textord_debug_blob) {
            tprintf ("Merging rows at (%g,%g), (%g,%g)\n",
              row->min_y (), row->max_y (),
              test_row->min_y (), test_row->max_y ());
          }
          test_row->set_limits (merge_bottom, merge_top);
          blob_it.set_to_list (test_row->blob_list ());
          blob_it.add_list_after (row->blob_list ());
          blob_it.sort (blob_x_order);
          row_it->backward ();
          delete row_it->extract ();
          row_it->forward ();
          bestover = -1.0f;      //force replacement
        }
        overlap = top - bottom;
        if (top > test_row->max_y ())
          overlap -= top - test_row->max_y ();
        if (bottom < test_row->min_y ())
          overlap -= test_row->min_y () - bottom;
        if (bestover >= rowsize - 1 && overlap >= rowsize - 1) {
          result = REJECT;
        }
        if (overlap > bestover) {
          bestover = overlap;    //find biggest overlap
          row = test_row;
        }
        if (testing_blob && textord_debug_blob) {
          tprintf("Test blob y=(%g,%g), row=(%f,%f), size=%g, overlap=%f->%f\n",
                  bottom, top, test_row->min_y(), test_row->max_y(),
                  rowsize, overlap, bestover);
        }
      }
    }
  }
  while (!row_it->at_last ()
    && test_row->min_y () <= top && test_row->max_y () >= bottom);
  while (row_it->data () != row)
    row_it->backward ();         //make it point to row
                                 //doesn't overlap much
  if (top - bottom - bestover > rowsize * textord_overlap_x &&
      (!textord_fix_makerow_bug || bestover < rowsize * textord_overlap_x)
    && result == ASSIGN)
    result = NEW_ROW;            //doesn't overlap enough
  best_row = row;
  return result;
}

pre_associate_blobs()

void pre_associate_blobs	(	ICOORD	page_tr,
		TO_BLOCK *	block,
		FCOORD	rotation,
		bool	testing_on
	)

Definition at line 1847 of file makerow.cpp.

  {
#ifndef GRAPHICS_DISABLED
  ScrollView::Color colour;                 //of boxes
#endif
  BLOBNBOX *blob;                //current blob
  BLOBNBOX *nextblob;            //next in list
  TBOX blob_box;
  FCOORD blob_rotation;          //inverse of rotation
  BLOBNBOX_IT blob_it;           //iterator
  BLOBNBOX_IT start_it;          //iterator
  TO_ROW_IT row_it = block->get_rows ();

#ifndef GRAPHICS_DISABLED
  colour = ScrollView::RED;
#endif

  blob_rotation = FCOORD (rotation.x (), -rotation.y ());
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
                                 //get blobs
    blob_it.set_to_list (row_it.data ()->blob_list ());
    for (blob_it.mark_cycle_pt (); !blob_it.cycled_list ();
    blob_it.forward ()) {
      blob = blob_it.data ();
      blob_box = blob->bounding_box ();
      start_it = blob_it;        //save start point
      //                      if (testing_on && textord_show_final_blobs)
      //                      {
      //                              tprintf("Blob at (%d,%d)->(%d,%d), addr=%x, count=%d\n",
      //                                      blob_box.left(),blob_box.bottom(),
      //                                      blob_box.right(),blob_box.top(),
      //                                      (void*)blob,blob_it.length());
      //                      }
      bool overlap;
      do {
        overlap = false;
        if (!blob_it.at_last ()) {
          nextblob = blob_it.data_relative(1);
          overlap = blob_box.major_x_overlap(nextblob->bounding_box());
          if (overlap) {
            blob->merge(nextblob); // merge new blob
            blob_box = blob->bounding_box(); // get bigger box
            blob_it.forward();
          }
        }
      }
      while (overlap);
      blob->chop (&start_it, &blob_it,
        blob_rotation,
        block->line_size * tesseract::CCStruct::kXHeightFraction *
        textord_chop_width);
      //attempt chop
    }
#ifndef GRAPHICS_DISABLED
    if (testing_on && textord_show_final_blobs) {
      if (to_win == nullptr)
        create_to_win(page_tr);
      to_win->Pen(colour);
      for (blob_it.mark_cycle_pt (); !blob_it.cycled_list ();
      blob_it.forward ()) {
        blob = blob_it.data ();
        blob_box = blob->bounding_box ();
        blob_box.rotate (rotation);
        if (!blob->joined_to_prev ()) {
          to_win->Rectangle (blob_box.left (), blob_box.bottom (),
            blob_box.right (), blob_box.top ());
        }
      }
      colour = (ScrollView::Color) (colour + 1);
      if (colour > ScrollView::MAGENTA)
        colour = ScrollView::RED;
    }
#endif
  }
}

row_spacing_order()

int row_spacing_order	(	const void *	item1,
		const void *	item2
	)

Definition at line 2619 of file makerow.cpp.

                                         {
                                 //converted ptr
  const TO_ROW *row1 = *reinterpret_cast<const TO_ROW* const*>(item1);
                                 //converted ptr
  const TO_ROW *row2 = *reinterpret_cast<const TO_ROW* const*>(item2);

  if (row1->spacing < row2->spacing)
    return -1;
  else if (row1->spacing > row2->spacing)
    return 1;
  else
    return 0;
}

row_y_order()

int row_y_order	(	const void *	item1,
		const void *	item2
	)

Definition at line 2597 of file makerow.cpp.

                                   {
                                 //converted ptr
  const TO_ROW *row1 = *reinterpret_cast<const TO_ROW* const*>(item1);
                                 //converted ptr
  const TO_ROW *row2 = *reinterpret_cast<const TO_ROW* const*>(item2);

  if (row1->parallel_c () > row2->parallel_c ())
    return -1;
  else if (row1->parallel_c () < row2->parallel_c ())
    return 1;
  else
    return 0;
}

segment_baseline()

bool segment_baseline	(	TO_ROW *	row,
		TO_BLOCK *	block,
		int32_t &	segments,
		int32_t *	xstarts
	)

Definition at line 2090 of file makerow.cpp.

  {
  bool needs_curve;             //needs curved line
  int blobcount;                 //no of blobs
  int blobindex;                 //current blob
  int last_state;                //above, on , below
  int state;                     //of current blob
  float yshift;                  //from baseline
  TBOX box;                       //blob box
  TBOX new_box;                   //new_it box
  float middle;                  //xcentre of blob
                                 //blobs
  BLOBNBOX_IT blob_it = row->blob_list ();
  BLOBNBOX_IT new_it = blob_it;  //front end
  SORTED_FLOATS yshifts;         //shifts from baseline

  needs_curve = false;
  box = box_next_pre_chopped (&blob_it);
  xstarts[0] = box.left ();
  segments = 1;
  blobcount = row->blob_list ()->length ();
  if (textord_oldbl_debug)
    tprintf ("Segmenting baseline of %d blobs at (%d,%d)\n",
      blobcount, box.left (), box.bottom ());
  if (blobcount <= textord_spline_medianwin
  || blobcount < textord_spline_minblobs) {
    blob_it.move_to_last ();
    box = blob_it.data ()->bounding_box ();
    xstarts[1] = box.right ();
    return false;
  }
  last_state = 0;
  new_it.mark_cycle_pt ();
  for (blobindex = 0; blobindex < textord_spline_medianwin; blobindex++) {
    new_box = box_next_pre_chopped (&new_it);
    middle = (new_box.left () + new_box.right ()) / 2.0;
    yshift = new_box.bottom () - row->line_m () * middle - row->line_c ();
                                 //record shift
    yshifts.add (yshift, blobindex);
    if (new_it.cycled_list ()) {
      xstarts[1] = new_box.right ();
      return false;
    }
  }
  for (blobcount = 0; blobcount < textord_spline_medianwin / 2; blobcount++)
    box = box_next_pre_chopped (&blob_it);
  do {
    new_box = box_next_pre_chopped (&new_it);
                                 //get middle one
    yshift = yshifts[textord_spline_medianwin / 2];
    if (yshift > textord_spline_shift_fraction * block->line_size)
      state = 1;
    else if (-yshift > textord_spline_shift_fraction * block->line_size)
      state = -1;
    else
      state = 0;
    if (state != 0)
      needs_curve = true;
    //              tprintf("State=%d, prev=%d, shift=%g\n",
    //                      state,last_state,yshift);
    if (state != last_state && blobcount > textord_spline_minblobs) {
      xstarts[segments++] = box.left ();
      blobcount = 0;
    }
    last_state = state;
    yshifts.remove (blobindex - textord_spline_medianwin);
    box = box_next_pre_chopped (&blob_it);
    middle = (new_box.left () + new_box.right ()) / 2.0;
    yshift = new_box.bottom () - row->line_m () * middle - row->line_c ();
    yshifts.add (yshift, blobindex);
    blobindex++;
    blobcount++;
  }
  while (!new_it.cycled_list ());
  if (blobcount > textord_spline_minblobs || segments == 1) {
    xstarts[segments] = new_box.right ();
  }
  else {
    xstarts[--segments] = new_box.right ();
  }
  if (textord_oldbl_debug)
    tprintf ("Made %d segments on row at (%d,%d)\n",
      segments, box.right (), box.bottom ());
  return needs_curve;
}

separate_underlines()

void separate_underlines	(	TO_BLOCK *	block,
		float	gradient,
		FCOORD	rotation,
		bool	testing_on
	)

Definition at line 1774 of file makerow.cpp.

                                          {  // correct orientation
  BLOBNBOX *blob;                // current blob
  C_BLOB *rotated_blob;          // rotated blob
  TO_ROW *row;                   // current row
  float length;                  // of g_vec
  TBOX blob_box;
  FCOORD blob_rotation;          // inverse of rotation
  FCOORD g_vec;                  // skew rotation
  BLOBNBOX_IT blob_it;           // iterator
                                 // iterator
  BLOBNBOX_IT under_it = &block->underlines;
  BLOBNBOX_IT large_it = &block->large_blobs;
  TO_ROW_IT row_it = block->get_rows();
  int min_blob_height = static_cast<int>(textord_min_blob_height_fraction *
                                         block->line_size + 0.5);

                                 // length of vector
  length = sqrt(1 + gradient * gradient);
  g_vec = FCOORD(1 / length, -gradient / length);
  blob_rotation = FCOORD(rotation.x(), -rotation.y());
  blob_rotation.rotate(g_vec);  // undoing everything
  for (row_it.mark_cycle_pt(); !row_it.cycled_list(); row_it.forward()) {
    row = row_it.data();
                                 // get blobs
    blob_it.set_to_list(row->blob_list());
    for (blob_it.mark_cycle_pt(); !blob_it.cycled_list();
         blob_it.forward()) {
      blob = blob_it.data();
      blob_box = blob->bounding_box();
      if (blob_box.width() > block->line_size * textord_underline_width) {
        ASSERT_HOST(blob->cblob() != nullptr);
        rotated_blob = crotate_cblob (blob->cblob(),
          blob_rotation);
        if (test_underline(
            testing_on && textord_show_final_rows,
            rotated_blob, static_cast<int16_t>(row->intercept()),
            static_cast<int16_t>(
                block->line_size *
                (tesseract::CCStruct::kXHeightFraction +
                 tesseract::CCStruct::kAscenderFraction / 2.0f)))) {
          under_it.add_after_then_move(blob_it.extract());
          if (testing_on && textord_show_final_rows) {
            tprintf("Underlined blob at:");
              rotated_blob->bounding_box().print();
            tprintf("Was:");
              blob_box.print();
          }
        } else if (CountOverlaps(blob->bounding_box(), min_blob_height,
                                 row->blob_list()) >
                   textord_max_blob_overlaps) {
          large_it.add_after_then_move(blob_it.extract());
          if (testing_on && textord_show_final_rows) {
            tprintf("Large blob overlaps %d blobs at:",
                    CountOverlaps(blob_box, min_blob_height,
                                  row->blob_list()));
            blob_box.print();
          }
        }
        delete rotated_blob;
      }
    }
  }
}

vigorous_noise_removal()

void vigorous_noise_removal

(

TO_BLOCK *

block

)

Definition at line 467 of file makerow.cpp.

                                             {
  TO_ROW_IT row_it = block->get_rows ();
  for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
    TO_ROW* row = row_it.data();
    BLOBNBOX_IT b_it = row->blob_list();
    // Estimate the xheight on the row.
    int max_height = 0;
    for (b_it.mark_cycle_pt(); !b_it.cycled_list(); b_it.forward()) {
      BLOBNBOX* blob = b_it.data();
      if (blob->bounding_box().height() > max_height)
        max_height = blob->bounding_box().height();
    }
    STATS hstats(0, max_height + 1);
    for (b_it.mark_cycle_pt(); !b_it.cycled_list(); b_it.forward()) {
      BLOBNBOX* blob = b_it.data();
      int height = blob->bounding_box().height();
      if (height >= kMinSize)
        hstats.add(blob->bounding_box().height(), 1);
    }
    float xheight = hstats.median();
    // Delete small objects.
    BLOBNBOX* prev = nullptr;
    for (b_it.mark_cycle_pt(); !b_it.cycled_list(); b_it.forward()) {
      BLOBNBOX* blob = b_it.data();
      const TBOX& box = blob->bounding_box();
      if (box.height() < kNoiseSize * xheight) {
        // Small so delete unless it looks like an i dot.
        if (prev != nullptr) {
          if (dot_of_i(blob, prev, row))
            continue;  // Looks OK.
        }
        if (!b_it.at_last()) {
          BLOBNBOX* next = b_it.data_relative(1);
          if (dot_of_i(blob, next, row))
            continue;  // Looks OK.
        }
        // It might be noise so get rid of it.
        delete blob->cblob();
        delete b_it.extract();
      } else {
        prev = blob;
      }
    }
  }
}

within_error_margin()

bool within_error_margin ( float  test, float  num, float  margin  )

inline

Definition at line 128 of file makerow.h.

                                                                     {
  return (test >= num * (1 - margin) && test <= num * (1 + margin));
}

Variable Documentation

textord_ascheight_mode_fraction

double textord_ascheight_mode_fraction = 0.15

"Min pile height to make ascheight"

Definition at line 92 of file makerow.cpp.

textord_ascx_ratio_max

double textord_ascx_ratio_max = 1.7

"Max cap/xheight"

Definition at line 96 of file makerow.cpp.

textord_ascx_ratio_min

double textord_ascx_ratio_min = 1.2

"Min cap/xheight"

Definition at line 95 of file makerow.cpp.

textord_cblob_blockocc

bool textord_cblob_blockocc = TRUE

"Use new projection for underlines"

textord_chop_width

double textord_chop_width = 1.5

"Max width before chopping"

Definition at line 77 of file makerow.cpp.

textord_debug_blob

bool textord_debug_blob = FALSE

"Print test blob information"

Definition at line 102 of file makerow.cpp.

textord_debug_xheights

bool textord_debug_xheights = FALSE

"Test xheight algorithms"

Definition at line 56 of file makerow.cpp.

textord_descx_ratio_max

double textord_descx_ratio_max = 0.6

"Max desc/xheight"

Definition at line 98 of file makerow.cpp.

textord_descx_ratio_min

double textord_descx_ratio_min = 0.15

"Min desc/xheight"

Definition at line 97 of file makerow.cpp.

textord_excess_blobsize

double textord_excess_blobsize = 1.3

"New row made if blob makes row this big"

Definition at line 84 of file makerow.cpp.

textord_fix_makerow_bug

bool textord_fix_makerow_bug = TRUE

"Prevent multiple baselines"

Definition at line 55 of file makerow.cpp.

textord_fix_xheight_bug

bool textord_fix_xheight_bug = TRUE

"Use spline baseline"

Definition at line 54 of file makerow.cpp.

textord_heavy_nr

bool textord_heavy_nr = FALSE

"Vigorously remove noise"

Definition at line 43 of file makerow.cpp.

textord_linespace_iqrlimit

double textord_linespace_iqrlimit = 0.2

"Max iqr/median for linespace"

Definition at line 75 of file makerow.cpp.

textord_lms_line_trials

int textord_lms_line_trials = 12

"Number of linew fits to do"

Definition at line 100 of file makerow.cpp.

textord_min_blob_height_fraction

double textord_min_blob_height_fraction = 0.75

"Min blob height/top to include blob top into xheight stats"

Definition at line 88 of file makerow.cpp.

textord_min_blobs_in_row

int textord_min_blobs_in_row = 4

"Min blobs before gradient counted"

Definition at line 63 of file makerow.cpp.

textord_min_linesize

double textord_min_linesize = 1.25

"* blob height for initial linesize"

Definition at line 82 of file makerow.cpp.

textord_min_xheight

int textord_min_xheight = 10

"Min credible pixel xheight"

Definition at line 68 of file makerow.cpp.

textord_minxh

double textord_minxh = 0.25

"fraction of linesize for min xheight"

Definition at line 81 of file makerow.cpp.

textord_new_initial_xheight

bool textord_new_initial_xheight = TRUE

"Use test xheight mechanism"

Definition at line 101 of file makerow.cpp.

textord_occupancy_threshold

double textord_occupancy_threshold = 0.4

"Fraction of neighbourhood"

Definition at line 85 of file makerow.cpp.

textord_old_baselines

bool textord_old_baselines = TRUE

"Use old baseline algorithm"

Definition at line 52 of file makerow.cpp.

textord_old_xheight

bool textord_old_xheight = TRUE

"Use old xheight algorithm"

Definition at line 53 of file makerow.cpp.

textord_parallel_baselines

bool textord_parallel_baselines = TRUE

"Force parallel baselines"

Definition at line 50 of file makerow.cpp.

textord_quadratic_baselines

bool textord_quadratic_baselines = FALSE

"Use quadratic splines"

textord_show_expanded_rows

bool textord_show_expanded_rows = FALSE

"Display rows after expanding"

Definition at line 46 of file makerow.cpp.

textord_show_final_blobs

bool textord_show_final_blobs = FALSE

"Display blob bounds after pre-ass"

Definition at line 48 of file makerow.cpp.

textord_show_final_rows

bool textord_show_final_rows = FALSE

"Display rows after final fitting"

Definition at line 47 of file makerow.cpp.

textord_show_initial_rows

bool textord_show_initial_rows = FALSE

"Display row accumulation"

Definition at line 44 of file makerow.cpp.

textord_show_parallel_rows

bool textord_show_parallel_rows = FALSE

"Display page correlated rows"

Definition at line 45 of file makerow.cpp.

textord_skew_ile

double textord_skew_ile = 0.5

"Ile of gradients for page skew"

Definition at line 73 of file makerow.cpp.

textord_skew_lag

double textord_skew_lag = 0.75

"Lag for skew on row accumulation"

Definition at line 74 of file makerow.cpp.

textord_spline_medianwin

int textord_spline_medianwin = 6

"Size of window for spline segmentation"

Definition at line 65 of file makerow.cpp.

textord_spline_minblobs

int textord_spline_minblobs = 8

"Min blobs in each spline segment"

Definition at line 64 of file makerow.cpp.

textord_spline_outlier_fraction

double textord_spline_outlier_fraction = 0.1

"Fraction of line spacing for outlier"

Definition at line 72 of file makerow.cpp.

textord_spline_shift_fraction

double textord_spline_shift_fraction = 0.02

"Fraction of line spacing for quad"

Definition at line 70 of file makerow.cpp.

textord_straight_baselines

bool textord_straight_baselines = FALSE

"Force straight baselines"

Definition at line 51 of file makerow.cpp.

textord_test_landscape

bool textord_test_landscape = FALSE

"Tests refer to land/port"

Definition at line 49 of file makerow.cpp.

textord_test_x

int textord_test_x = -INT32_MAX

"coord of test pt"

Definition at line 61 of file makerow.cpp.

textord_test_y

int textord_test_y = -INT32_MAX

"coord of test pt"

Definition at line 62 of file makerow.cpp.

textord_underline_width

double textord_underline_width = 2.0

"Multiple of line_size for underline"

Definition at line 86 of file makerow.cpp.

textord_width_limit

double textord_width_limit = 8

"Max width of blobs to make rows"

Definition at line 76 of file makerow.cpp.

textord_xheight_error_margin

double textord_xheight_error_margin = 0.1

"Accepted variation"

Definition at line 99 of file makerow.cpp.

textord_xheight_mode_fraction

double textord_xheight_mode_fraction = 0.4

"Min pile height to make xheight"

Definition at line 90 of file makerow.cpp.