tesseract/textord/tospace.cpp

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// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
/**********************************************************************
* tospace.cpp
*
* Compute fuzzy word spacing thresholds for each row.
* I.e. set : max_nonspace
* space_threshold
* min_space
* kern_size
* space_size
* for each row.
* ONLY FOR PROPORTIONAL BLOCKS - FIXED PITCH IS ASSUMED ALREADY DONE
*
* Note: functions in this file were originally not members of any
* class or enclosed by any namespace. Now they are all static members
* of the Textord class.
*
**********************************************************************/
#include "drawtord.h"
#include "ndminx.h"
#include "statistc.h"
#include "textord.h"
#include "tovars.h"
// Include automatically generated configuration file if running autoconf.
#ifdef HAVE_CONFIG_H
#include "config_auto.h"
#endif
#define MAXSPACING 128 /*max expected spacing in pix */
namespace tesseract {
void Textord::to_spacing(
ICOORD page_tr, //topright of page
TO_BLOCK_LIST *blocks //blocks on page
) {
TO_BLOCK_IT block_it; //iterator
TO_BLOCK *block; //current block;
TO_ROW_IT row_it; //row iterator
TO_ROW *row; //current row
int block_index; //block number
int row_index; //row number
//estimated width of real spaces for whole block
inT16 block_space_gap_width;
//estimated width of non space gaps for whole block
inT16 block_non_space_gap_width;
BOOL8 old_text_ord_proportional;//old fixed/prop result
GAPMAP *gapmap = NULL; //map of big vert gaps in blk
block_it.set_to_list (blocks);
block_index = 1;
for (block_it.mark_cycle_pt (); !block_it.cycled_list ();
block_it.forward ()) {
block = block_it.data ();
gapmap = new GAPMAP (block);
block_spacing_stats(block,
gapmap,
old_text_ord_proportional,
block_space_gap_width,
block_non_space_gap_width);
// Make sure relative values of block-level space and non-space gap
// widths are reasonable. The ratio of 1:3 is also used in
// block_spacing_stats, to corrrect the block_space_gap_width
// Useful for arabic and hindi, when the non-space gap width is
// often over-estimated and should not be trusted. A similar ratio
// is found in block_spacing_stats.
if (tosp_old_to_method && tosp_old_to_constrain_sp_kn &&
(float) block_space_gap_width / block_non_space_gap_width < 3.0) {
block_non_space_gap_width = (inT16) floor (block_space_gap_width / 3.0);
}
row_it.set_to_list (block->get_rows ());
row_index = 1;
for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
row = row_it.data ();
if ((row->pitch_decision == PITCH_DEF_PROP) ||
(row->pitch_decision == PITCH_CORR_PROP)) {
if ((tosp_debug_level > 0) && !old_text_ord_proportional)
tprintf ("Block %d Row %d: Now Proportional\n",
block_index, row_index);
row_spacing_stats(row,
gapmap,
block_index,
row_index,
block_space_gap_width,
block_non_space_gap_width);
}
else {
if ((tosp_debug_level > 0) && old_text_ord_proportional)
tprintf
("Block %d Row %d: Now Fixed Pitch Decision:%d fp flag:%f\n",
block_index, row_index, row->pitch_decision,
row->fixed_pitch);
}
#ifndef GRAPHICS_DISABLED
if (textord_show_initial_words)
plot_word_decisions (to_win, (inT16) row->fixed_pitch, row);
#endif
row_index++;
}
delete gapmap;
block_index++;
}
}
/*************************************************************************
* block_spacing_stats()
*************************************************************************/
void Textord::block_spacing_stats(
TO_BLOCK *block,
GAPMAP *gapmap,
BOOL8 &old_text_ord_proportional,
inT16 &block_space_gap_width, // resulting estimate
inT16 &block_non_space_gap_width // resulting estimate
) {
TO_ROW_IT row_it; // row iterator
TO_ROW *row; // current row
BLOBNBOX_IT blob_it; // iterator
STATS centre_to_centre_stats (0, MAXSPACING);
// DEBUG USE ONLY
STATS all_gap_stats (0, MAXSPACING);
STATS space_gap_stats (0, MAXSPACING);
inT16 minwidth = MAXSPACING; // narrowest blob
TBOX blob_box;
TBOX prev_blob_box;
inT16 centre_to_centre;
inT16 gap_width;
float real_space_threshold;
float iqr_centre_to_centre; // DEBUG USE ONLY
float iqr_all_gap_stats; // DEBUG USE ONLY
inT32 end_of_row;
inT32 row_length;
row_it.set_to_list (block->get_rows ());
for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
row = row_it.data ();
if (!row->blob_list ()->empty () &&
(!tosp_only_use_prop_rows ||
(row->pitch_decision == PITCH_DEF_PROP) ||
(row->pitch_decision == PITCH_CORR_PROP))) {
blob_it.set_to_list (row->blob_list ());
blob_it.mark_cycle_pt ();
end_of_row = blob_it.data_relative (-1)->bounding_box ().right ();
if (tosp_use_pre_chopping)
blob_box = box_next_pre_chopped (&blob_it);
else if (tosp_stats_use_xht_gaps)
blob_box = reduced_box_next (row, &blob_it);
else
blob_box = box_next (&blob_it);
row_length = end_of_row - blob_box.left ();
if (blob_box.width () < minwidth)
minwidth = blob_box.width ();
prev_blob_box = blob_box;
while (!blob_it.cycled_list ()) {
if (tosp_use_pre_chopping)
blob_box = box_next_pre_chopped (&blob_it);
else if (tosp_stats_use_xht_gaps)
blob_box = reduced_box_next (row, &blob_it);
else
blob_box = box_next (&blob_it);
if (blob_box.width () < minwidth)
minwidth = blob_box.width ();
gap_width = blob_box.left () - prev_blob_box.right ();
if (!ignore_big_gap (row, row_length, gapmap,
prev_blob_box.right (), blob_box.left ())) {
all_gap_stats.add (gap_width, 1);
centre_to_centre = (blob_box.left () + blob_box.right () -
(prev_blob_box.left () +
prev_blob_box.right ())) / 2;
//DEBUG
centre_to_centre_stats.add (centre_to_centre, 1);
// DEBUG
}
prev_blob_box = blob_box;
}
}
}
//Inadequate samples
if (all_gap_stats.get_total () <= 1) {
block_non_space_gap_width = minwidth;
block_space_gap_width = -1; //No est. space width
//DEBUG
old_text_ord_proportional = TRUE;
}
else {
/* For debug only ..... */
iqr_centre_to_centre = centre_to_centre_stats.ile (0.75) -
centre_to_centre_stats.ile (0.25);
iqr_all_gap_stats = all_gap_stats.ile (0.75) - all_gap_stats.ile (0.25);
old_text_ord_proportional =
iqr_centre_to_centre * 2 > iqr_all_gap_stats;
/* .......For debug only */
/*
The median of the gaps is used as an estimate of the NON-SPACE gap width.
This RELIES on the assumption that there are more gaps WITHIN words than
BETWEEN words in a block
Now try to estimate the width of a real space for all real spaces in the
block. Do this by using a crude threshold to ignore "narrow" gaps, then
find the median of the "wide" gaps and use this.
*/
block_non_space_gap_width = (inT16) floor (all_gap_stats.median ());
// median gap
row_it.set_to_list (block->get_rows ());
for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) {
row = row_it.data ();
if (!row->blob_list ()->empty () &&
(!tosp_only_use_prop_rows ||
(row->pitch_decision == PITCH_DEF_PROP) ||
(row->pitch_decision == PITCH_CORR_PROP))) {
real_space_threshold =
MAX (tosp_init_guess_kn_mult * block_non_space_gap_width,
tosp_init_guess_xht_mult * row->xheight);
blob_it.set_to_list (row->blob_list ());
blob_it.mark_cycle_pt ();
end_of_row =
blob_it.data_relative (-1)->bounding_box ().right ();
if (tosp_use_pre_chopping)
blob_box = box_next_pre_chopped (&blob_it);
else if (tosp_stats_use_xht_gaps)
blob_box = reduced_box_next (row, &blob_it);
else
blob_box = box_next (&blob_it);
row_length = blob_box.left () - end_of_row;
prev_blob_box = blob_box;
while (!blob_it.cycled_list ()) {
if (tosp_use_pre_chopping)
blob_box = box_next_pre_chopped (&blob_it);
else if (tosp_stats_use_xht_gaps)
blob_box = reduced_box_next (row, &blob_it);
else
blob_box = box_next (&blob_it);
gap_width = blob_box.left () - prev_blob_box.right ();
if ((gap_width > real_space_threshold) &&
!ignore_big_gap (row, row_length, gapmap,
prev_blob_box.right (),
blob_box.left ())) {
/*
If tosp_use_cert_spaces is enabled, the estimate of the space gap is
restricted to obvious spaces - those wider than half the xht or those
with wide blobs on both sides - i.e not things that are suspect 1's or
punctuation that is sometimes widely spaced.
*/
if (!tosp_block_use_cert_spaces ||
(gap_width >
tosp_fuzzy_space_factor2 * row->xheight)
||
((gap_width >
tosp_fuzzy_space_factor1 * row->xheight)
&& (!tosp_narrow_blobs_not_cert
|| (!narrow_blob (row, prev_blob_box)
&& !narrow_blob (row, blob_box))))
|| (wide_blob (row, prev_blob_box)
&& wide_blob (row, blob_box)))
space_gap_stats.add (gap_width, 1);
}
prev_blob_box = blob_box;
}
}
}
//Inadequate samples
if (space_gap_stats.get_total () <= 2)
block_space_gap_width = -1;//No est. space width
else
block_space_gap_width =
MAX ((inT16) floor (space_gap_stats.median ()),
3 * block_non_space_gap_width);
}
}
/*************************************************************************
* row_spacing_stats()
* Set values for min_space, max_non_space based on row stats only
* If failure - return 0 values.
*************************************************************************/
void Textord::row_spacing_stats(
TO_ROW *row,
GAPMAP *gapmap,
inT16 block_idx,
inT16 row_idx,
inT16 block_space_gap_width, //estimate for block
inT16 block_non_space_gap_width //estimate for block
) {
//iterator
BLOBNBOX_IT blob_it = row->blob_list ();
STATS all_gap_stats (0, MAXSPACING);
STATS cert_space_gap_stats (0, MAXSPACING);
STATS all_space_gap_stats (0, MAXSPACING);
STATS small_gap_stats (0, MAXSPACING);
TBOX blob_box;
TBOX prev_blob_box;
inT16 gap_width;
inT16 real_space_threshold = 0;
inT16 max = 0;
inT16 index;
inT16 large_gap_count = 0;
BOOL8 suspected_table;
inT32 max_max_nonspace; //upper bound
BOOL8 good_block_space_estimate = block_space_gap_width > 0;
inT32 end_of_row;
inT32 row_length = 0;
float sane_space;
inT32 sane_threshold;
/* Collect first pass stats for row */
if (!good_block_space_estimate)
block_space_gap_width = inT16 (floor (row->xheight / 2));
if (!row->blob_list ()->empty ()) {
if (tosp_threshold_bias1 > 0)
real_space_threshold =
block_non_space_gap_width +
inT16 (floor (0.5 +
tosp_threshold_bias1 * (block_space_gap_width -
block_non_space_gap_width)));
else
real_space_threshold = //Old TO method
(block_space_gap_width + block_non_space_gap_width) / 2;
blob_it.set_to_list (row->blob_list ());
blob_it.mark_cycle_pt ();
end_of_row = blob_it.data_relative (-1)->bounding_box ().right ();
if (tosp_use_pre_chopping)
blob_box = box_next_pre_chopped (&blob_it);
else if (tosp_stats_use_xht_gaps)
blob_box = reduced_box_next (row, &blob_it);
else
blob_box = box_next (&blob_it);
row_length = end_of_row - blob_box.left ();
prev_blob_box = blob_box;
while (!blob_it.cycled_list ()) {
if (tosp_use_pre_chopping)
blob_box = box_next_pre_chopped (&blob_it);
else if (tosp_stats_use_xht_gaps)
blob_box = reduced_box_next (row, &blob_it);
else
blob_box = box_next (&blob_it);
gap_width = blob_box.left () - prev_blob_box.right ();
if (ignore_big_gap (row, row_length, gapmap,
prev_blob_box.right (), blob_box.left ()))
large_gap_count++;
else {
if (gap_width >= real_space_threshold) {
if (!tosp_row_use_cert_spaces ||
(gap_width > tosp_fuzzy_space_factor2 * row->xheight) ||
((gap_width > tosp_fuzzy_space_factor1 * row->xheight)
&& (!tosp_narrow_blobs_not_cert
|| (!narrow_blob (row, prev_blob_box)
&& !narrow_blob (row, blob_box))))
|| (wide_blob (row, prev_blob_box)
&& wide_blob (row, blob_box)))
cert_space_gap_stats.add (gap_width, 1);
all_space_gap_stats.add (gap_width, 1);
}
else
small_gap_stats.add (gap_width, 1);
all_gap_stats.add (gap_width, 1);
}
prev_blob_box = blob_box;
}
}
suspected_table = (large_gap_count > 1) ||
((large_gap_count > 0) &&
(all_gap_stats.get_total () <= tosp_few_samples));
/* Now determine row kern size, space size and threshold */
if ((cert_space_gap_stats.get_total () >=
tosp_enough_space_samples_for_median) ||
((suspected_table ||
all_gap_stats.get_total () <= tosp_short_row) &&
cert_space_gap_stats.get_total () > 0)) {
old_to_method(row,
&all_gap_stats,
&cert_space_gap_stats,
&small_gap_stats,
block_space_gap_width,
block_non_space_gap_width);
} else {
if (!tosp_recovery_isolated_row_stats ||
!isolated_row_stats (row, gapmap, &all_gap_stats, suspected_table,
block_idx, row_idx)) {
if (tosp_row_use_cert_spaces && (tosp_debug_level > 5))
tprintf ("B:%d R:%d -- Inadequate certain spaces.\n",
block_idx, row_idx);
if (tosp_row_use_cert_spaces1 && good_block_space_estimate) {
//Use block default
row->space_size = block_space_gap_width;
if (all_gap_stats.get_total () > tosp_redo_kern_limit)
row->kern_size = all_gap_stats.median ();
else
row->kern_size = block_non_space_gap_width;
row->space_threshold =
inT32 (floor ((row->space_size + row->kern_size) /
tosp_old_sp_kn_th_factor));
}
else
old_to_method(row,
&all_gap_stats,
&all_space_gap_stats,
&small_gap_stats,
block_space_gap_width,
block_non_space_gap_width);
}
}
if (tosp_improve_thresh && !suspected_table)
improve_row_threshold(row, &all_gap_stats);
/* Now lets try to be careful not to do anything silly with tables when we
are ignoring big gaps*/
if (tosp_sanity_method == 0) {
if (suspected_table &&
(row->space_size < tosp_table_kn_sp_ratio * row->kern_size)) {
if (tosp_debug_level > 5)
tprintf("B:%d R:%d -- DON'T BELIEVE SPACE %3.2f %d %3.2f.\n", block_idx,
row_idx, row->kern_size, row->space_threshold, row->space_size);
row->space_threshold =
(inT32) (tosp_table_kn_sp_ratio * row->kern_size);
row->space_size = MAX (row->space_threshold + 1, row->xheight);
}
}
else if (tosp_sanity_method == 1) {
sane_space = row->space_size;
/* NEVER let space size get too close to kern size */
if ((row->space_size < tosp_min_sane_kn_sp * MAX (row->kern_size, 2.5))
|| ((row->space_size - row->kern_size) <
(tosp_silly_kn_sp_gap * row->xheight))) {
if (good_block_space_estimate &&
(block_space_gap_width >= tosp_min_sane_kn_sp * row->kern_size))
sane_space = block_space_gap_width;
else
sane_space =
MAX (tosp_min_sane_kn_sp * MAX (row->kern_size, 2.5),
row->xheight / 2);
if (tosp_debug_level > 5)
tprintf("B:%d R:%d -- DON'T BELIEVE SPACE %3.2f %d %3.2f -> %3.2f.\n",
block_idx, row_idx, row->kern_size, row->space_threshold,
row->space_size, sane_space);
row->space_size = sane_space;
row->space_threshold =
inT32 (floor ((row->space_size + row->kern_size) /
tosp_old_sp_kn_th_factor));
}
/* NEVER let threshold get VERY far away from kern */
sane_threshold = inT32 (floor (tosp_max_sane_kn_thresh *
MAX (row->kern_size, 2.5)));
if (row->space_threshold > sane_threshold) {
if (tosp_debug_level > 5)
tprintf ("B:%d R:%d -- DON'T BELIEVE THRESH %3.2f %d %3.2f->%d.\n",
block_idx, row_idx,
row->kern_size,
row->space_threshold, row->space_size, sane_threshold);
row->space_threshold = sane_threshold;
if (row->space_size <= sane_threshold)
row->space_size = row->space_threshold + 1.0f;
}
/* Beware of tables - there may be NO spaces */
if (suspected_table) {
sane_space = MAX (tosp_table_kn_sp_ratio * row->kern_size,
tosp_table_xht_sp_ratio * row->xheight);
sane_threshold = inT32 (floor ((sane_space + row->kern_size) / 2));
if ((row->space_size < sane_space) ||
(row->space_threshold < sane_threshold)) {
if (tosp_debug_level > 5)
tprintf ("B:%d R:%d -- SUSPECT NO SPACES %3.2f %d %3.2f.\n",
block_idx, row_idx,
row->kern_size,
row->space_threshold, row->space_size);
//the minimum sane value
row->space_threshold = (inT32) sane_space;
row->space_size = MAX (row->space_threshold + 1, row->xheight);
}
}
}
/* Now lets try to put some error limits on the threshold */
if (tosp_old_to_method) {
/* Old textord made a space if gap >= threshold */
//NO FUZZY SPACES YET
row->max_nonspace = row->space_threshold;
//NO FUZZY SPACES YET
row->min_space = row->space_threshold + 1;
}
else {
/* Any gap greater than 0.6 x-ht is bound to be a space (isn't it:-) */
row->min_space =
MIN (inT32 (ceil (tosp_fuzzy_space_factor * row->xheight)),
inT32 (row->space_size));
if (row->min_space <= row->space_threshold)
// Don't be silly
row->min_space = row->space_threshold + 1;
/*
Lets try to guess the max certain kern gap by looking at the cluster of
kerns for the row. The row is proportional so the kerns should cluster
tightly at the bottom of the distribution. We also expect most gaps to be
kerns. Find the maximum of the kern piles between 0 and twice the kern
estimate. Piles before the first one with less than 1/10 the maximum
number of samples can be taken as certain kerns.
Of course, there are some cases where the kern peak and space peaks merge,
so we will put an UPPER limit on the max certain kern gap of some fraction
below the threshold.
*/
max_max_nonspace = inT32 ((row->space_threshold + row->kern_size) / 2);
//default
row->max_nonspace = max_max_nonspace;
for (index = 0; index <= max_max_nonspace; index++) {
if (all_gap_stats.pile_count (index) > max)
max = all_gap_stats.pile_count (index);
if ((index > row->kern_size) &&
(all_gap_stats.pile_count (index) < 0.1 * max)) {
row->max_nonspace = index;
break;
}
}
}
/* Yet another algorithm - simpler this time - just choose a fraction of the
threshold to space range */
if ((tosp_fuzzy_sp_fraction > 0) &&
(row->space_size > row->space_threshold))
row->min_space = MAX (row->min_space,
(inT32) ceil (row->space_threshold +
tosp_fuzzy_sp_fraction *
(row->space_size -
row->space_threshold)));
/* Ensure that ANY space less than some multiplier times the kern size is
fuzzy. In tables there is a risk of erroneously setting a small space size
when there are no real spaces. Sometimes tables have text squashed into
columns so that the kn->sp ratio is small anyway - this means that we can't
use this to force a wider separation - hence we rely on context to join any
dubious breaks. */
if ((tosp_table_fuzzy_kn_sp_ratio > 0) &&
(suspected_table || tosp_fuzzy_limit_all))
row->min_space = MAX (row->min_space,
(inT32) ceil (tosp_table_fuzzy_kn_sp_ratio *
row->kern_size));
if ((tosp_fuzzy_kn_fraction > 0) && (row->kern_size < row->space_threshold)) {
row->max_nonspace = (inT32) floor (0.5 + row->kern_size +
tosp_fuzzy_kn_fraction *
(row->space_threshold -
row->kern_size));
}
if (row->max_nonspace > row->space_threshold) {
// Don't be silly
row->max_nonspace = row->space_threshold;
}
if (tosp_debug_level > 5)
tprintf
("B:%d R:%d L:%d-- Kn:%d Sp:%d Thr:%d -- Kn:%3.2f (%d) Thr:%d (%d) Sp:%3.2f\n",
block_idx, row_idx, row_length, block_non_space_gap_width,
block_space_gap_width, real_space_threshold, row->kern_size,
row->max_nonspace, row->space_threshold, row->min_space,
row->space_size);
if (tosp_debug_level > 10)
tprintf("row->kern_size = %3.2f, row->space_size = %3.2f, "
"row->space_threshold = %d\n",
row->kern_size, row->space_size, row->space_threshold);
}
void Textord::old_to_method(
TO_ROW *row,
STATS *all_gap_stats,
STATS *space_gap_stats,
STATS *small_gap_stats,
inT16 block_space_gap_width, //estimate for block
inT16 block_non_space_gap_width //estimate for block
) {
/* First, estimate row space size */
/* Old to condition was > 2 */
if (space_gap_stats->get_total () >= tosp_enough_space_samples_for_median) {
//Adequate samples
/* Set space size to median of spaces BUT limits it if it seems wildly out */
row->space_size = space_gap_stats->median ();
if (row->space_size > block_space_gap_width * 1.5) {
if (tosp_old_to_bug_fix)
row->space_size = block_space_gap_width * 1.5;
else
//BUG??? should be *1.5
row->space_size = block_space_gap_width;
}
if (row->space_size < (block_non_space_gap_width * 2) + 1)
row->space_size = (block_non_space_gap_width * 2) + 1;
}
//Only 1 or 2 samples
else if (space_gap_stats->get_total () >= 1) {
//hence mean not median
row->space_size = space_gap_stats->mean ();
if (row->space_size > block_space_gap_width * 1.5) {
if (tosp_old_to_bug_fix)
row->space_size = block_space_gap_width * 1.5;
else
//BUG??? should be *1.5
row->space_size = block_space_gap_width;
}
if (row->space_size < (block_non_space_gap_width * 3) + 1)
row->space_size = (block_non_space_gap_width * 3) + 1;
}
else {
//Use block default
row->space_size = block_space_gap_width;
}
/* Next, estimate row kern size */
if ((tosp_only_small_gaps_for_kern) &&
(small_gap_stats->get_total () > tosp_redo_kern_limit))
row->kern_size = small_gap_stats->median ();
else if (all_gap_stats->get_total () > tosp_redo_kern_limit)
row->kern_size = all_gap_stats->median ();
else //old TO -SAME FOR ALL ROWS
row->kern_size = block_non_space_gap_width;
/* Finally, estimate row space threshold */
if (tosp_threshold_bias2 > 0) {
row->space_threshold =
inT32 (floor (0.5 + row->kern_size +
tosp_threshold_bias2 * (row->space_size -
row->kern_size)));
} else {
/*
NOTE old text ord uses (space_size + kern_size + 1)/2 as the threshold
and holds this in a float. The use is with a >= test
NEW textord uses an integer threshold and a > test
It comes to the same thing.
(Though there is a difference in that old textor has integer space_size
and kern_size.)
*/
row->space_threshold =
inT32 (floor ((row->space_size + row->kern_size) / 2));
}
// Apply the same logic and ratios as in row_spacing_stats to
// restrict relative values of the row's space_size, kern_size, and
// space_threshold
if (tosp_old_to_constrain_sp_kn && tosp_sanity_method == 1 &&
((row->space_size <
tosp_min_sane_kn_sp * MAX (row->kern_size, 2.5)) ||
((row->space_size - row->kern_size) <
tosp_silly_kn_sp_gap * row->xheight))) {
if (row->kern_size > 2.5)
row->kern_size = row->space_size / tosp_min_sane_kn_sp;
row->space_threshold = inT32 (floor ((row->space_size + row->kern_size) /
tosp_old_sp_kn_th_factor));
}
}
/*************************************************************************
* isolated_row_stats()
* Set values for min_space, max_non_space based on row stats only
*************************************************************************/
BOOL8 Textord::isolated_row_stats(TO_ROW *row,
GAPMAP *gapmap,
STATS *all_gap_stats,
BOOL8 suspected_table,
inT16 block_idx,
inT16 row_idx) {
float kern_estimate;
float crude_threshold_estimate;
inT16 small_gaps_count;
inT16 total;
//iterator
BLOBNBOX_IT blob_it = row->blob_list ();
STATS cert_space_gap_stats (0, MAXSPACING);
STATS all_space_gap_stats (0, MAXSPACING);
STATS small_gap_stats (0, MAXSPACING);
TBOX blob_box;
TBOX prev_blob_box;
inT16 gap_width;
inT32 end_of_row;
inT32 row_length;
kern_estimate = all_gap_stats->median ();
crude_threshold_estimate = MAX (tosp_init_guess_kn_mult * kern_estimate,
tosp_init_guess_xht_mult * row->xheight);
small_gaps_count = stats_count_under (all_gap_stats,
(inT16)
ceil (crude_threshold_estimate));
total = all_gap_stats->get_total ();
if ((total <= tosp_redo_kern_limit) ||
((small_gaps_count / (float) total) < tosp_enough_small_gaps) ||
(total - small_gaps_count < 1)) {
if (tosp_debug_level > 5)
tprintf("B:%d R:%d -- Can't do isolated row stats.\n", block_idx,
row_idx);
return FALSE;
}
blob_it.set_to_list (row->blob_list ());
blob_it.mark_cycle_pt ();
end_of_row = blob_it.data_relative (-1)->bounding_box ().right ();
if (tosp_use_pre_chopping)
blob_box = box_next_pre_chopped (&blob_it);
else if (tosp_stats_use_xht_gaps)
blob_box = reduced_box_next (row, &blob_it);
else
blob_box = box_next (&blob_it);
row_length = end_of_row - blob_box.left ();
prev_blob_box = blob_box;
while (!blob_it.cycled_list ()) {
if (tosp_use_pre_chopping)
blob_box = box_next_pre_chopped (&blob_it);
else if (tosp_stats_use_xht_gaps)
blob_box = reduced_box_next (row, &blob_it);
else
blob_box = box_next (&blob_it);
gap_width = blob_box.left () - prev_blob_box.right ();
if (!ignore_big_gap (row, row_length, gapmap,
prev_blob_box.right (), blob_box.left ()) &&
(gap_width > crude_threshold_estimate)) {
if ((gap_width > tosp_fuzzy_space_factor2 * row->xheight) ||
((gap_width > tosp_fuzzy_space_factor1 * row->xheight) &&
(!tosp_narrow_blobs_not_cert ||
(!narrow_blob (row, prev_blob_box) &&
!narrow_blob (row, blob_box)))) ||
(wide_blob (row, prev_blob_box) && wide_blob (row, blob_box)))
cert_space_gap_stats.add (gap_width, 1);
all_space_gap_stats.add (gap_width, 1);
}
if (gap_width < crude_threshold_estimate)
small_gap_stats.add (gap_width, 1);
prev_blob_box = blob_box;
}
if (cert_space_gap_stats.get_total () >=
tosp_enough_space_samples_for_median)
//median
row->space_size = cert_space_gap_stats.median ();
else if (suspected_table && (cert_space_gap_stats.get_total () > 0))
//to avoid spaced
row->space_size = cert_space_gap_stats.mean ();
// 1's in tables
else if (all_space_gap_stats.get_total () >=
tosp_enough_space_samples_for_median)
//median
row->space_size = all_space_gap_stats.median ();
else
row->space_size = all_space_gap_stats.mean ();
if (tosp_only_small_gaps_for_kern)
row->kern_size = small_gap_stats.median ();
else
row->kern_size = all_gap_stats->median ();
row->space_threshold =
inT32 (floor ((row->space_size + row->kern_size) / 2));
/* Sanity check */
if ((row->kern_size >= row->space_threshold) ||
(row->space_threshold >= row->space_size) ||
(row->space_threshold <= 0)) {
if (tosp_debug_level > 5)
tprintf ("B:%d R:%d -- Isolated row stats SANITY FAILURE: %f %d %f\n",
block_idx, row_idx,
row->kern_size, row->space_threshold, row->space_size);
row->kern_size = 0.0f;
row->space_threshold = 0;
row->space_size = 0.0f;
return FALSE;
}
if (tosp_debug_level > 5)
tprintf ("B:%d R:%d -- Isolated row stats: %f %d %f\n",
block_idx, row_idx,
row->kern_size, row->space_threshold, row->space_size);
return TRUE;
}
inT16 Textord::stats_count_under(STATS *stats, inT16 threshold) {
inT16 index;
inT16 total = 0;
for (index = 0; index < threshold; index++)
total += stats->pile_count (index);
return total;
}
/*************************************************************************
* improve_row_threshold()
* Try to recognise a "normal line" -
* > 25 gaps
* && space > 3 * kn && space > 10
* (I.e. reasonably large space and kn:sp ratio)
* && > 3/4 # gaps < kn + (sp - kn)/3
* (I.e. most gaps are well away from space estimate)
* && a gap of max( 3, (sp - kn)/3 ) empty histogram positions is found
* somewhere in the histogram between kn and sp
* THEN set the threshold and fuzzy limits to this gap - ie NO fuzzies
* NO!!!!! the bristol line has "11" with a gap of 12 between the 1's!!!
* try moving the default threshold to within this band but leave the
* fuzzy limit calculation as at present.
*************************************************************************/
void Textord::improve_row_threshold(TO_ROW *row, STATS *all_gap_stats) {
float sp = row->space_size;
float kn = row->kern_size;
inT16 reqd_zero_width = 0;
inT16 zero_width = 0;
inT16 zero_start = 0;
inT16 index = 0;
if (tosp_debug_level > 10)
tprintf ("Improve row threshold 0");
if ((all_gap_stats->get_total () <= 25) ||
(sp <= 10) ||
(sp <= 3 * kn) ||
(stats_count_under (all_gap_stats,
(inT16) ceil (kn + (sp - kn) / 3 + 0.5)) <
(0.75 * all_gap_stats->get_total ())))
return;
if (tosp_debug_level > 10)
tprintf (" 1");
/*
Look for the first region of all 0's in the histogram which is wider than
max( 3, (sp - kn)/3 ) and starts between kn and sp. If found, and current
threshold is not within it, move the threshold so that is is just inside it.
*/
reqd_zero_width = (inT16) floor ((sp - kn) / 3 + 0.5);
if (reqd_zero_width < 3)
reqd_zero_width = 3;
for (index = inT16 (ceil (kn)); index < inT16 (floor (sp)); index++) {
if (all_gap_stats->pile_count (index) == 0) {
if (zero_width == 0)
zero_start = index;
zero_width++;
}
else {
if (zero_width >= reqd_zero_width)
break;
else {
zero_width = 0;
}
}
}
index--;
if (tosp_debug_level > 10)
tprintf (" reqd_z_width: %d found %d 0's, starting %d; thresh: %d/n",
reqd_zero_width, zero_width, zero_start, row->space_threshold);
if ((zero_width < reqd_zero_width) ||
((row->space_threshold >= zero_start) &&
(row->space_threshold <= index)))
return;
if (tosp_debug_level > 10)
tprintf (" 2");
if (row->space_threshold < zero_start) {
if (tosp_debug_level > 5)
tprintf
("Improve row kn:%5.2f sp:%5.2f 0's: %d -> %d thresh:%d -> %d\n",
kn, sp, zero_start, index, row->space_threshold, zero_start);
row->space_threshold = zero_start;
}
if (row->space_threshold > index) {
if (tosp_debug_level > 5)
tprintf
("Improve row kn:%5.2f sp:%5.2f 0's: %d -> %d thresh:%d -> %d\n",
kn, sp, zero_start, index, row->space_threshold, index);
row->space_threshold = index;
}
}
/**********************************************************************
* make_prop_words
*
* Convert a TO_BLOCK to a BLOCK.
**********************************************************************/
ROW *Textord::make_prop_words(
TO_ROW *row, // row to make
FCOORD rotation // for drawing
) {
BOOL8 bol; // start of line
/* prev_ values are for start of word being built. non prev_ values are for
the gap between the word being built and the next one. */
BOOL8 prev_fuzzy_sp; // probably space
BOOL8 prev_fuzzy_non; // probably not
uinT8 prev_blanks; // in front of word
BOOL8 fuzzy_sp = false; // probably space
BOOL8 fuzzy_non = false; // probably not
uinT8 blanks = 0; // in front of word
BOOL8 prev_gap_was_a_space = FALSE;
BOOL8 break_at_next_gap = FALSE;
ROW *real_row; // output row
C_OUTLINE_IT cout_it;
C_BLOB_LIST cblobs;
C_BLOB_IT cblob_it = &cblobs;
WERD_LIST words;
WERD_IT word_it; // new words
WERD *word; // new word
WERD_IT rep_char_it; // repeated char words
inT32 next_rep_char_word_right = MAX_INT32;
float repetition_spacing; // gap between repetitions
inT32 xstarts[2]; // row ends
inT32 prev_x; // end of prev blob
BLOBNBOX *bblob; // current blob
TBOX blob_box; // bounding box
BLOBNBOX_IT box_it; // iterator
TBOX prev_blob_box;
TBOX next_blob_box;
inT16 prev_gap = MAX_INT16;
inT16 current_gap = MAX_INT16;
inT16 next_gap = MAX_INT16;
inT16 prev_within_xht_gap = MAX_INT16;
inT16 current_within_xht_gap = MAX_INT16;
inT16 next_within_xht_gap = MAX_INT16;
inT16 word_count = 0;
rep_char_it.set_to_list (&(row->rep_words));
if (!rep_char_it.empty ()) {
next_rep_char_word_right =
rep_char_it.data ()->bounding_box ().right ();
}
prev_x = -MAX_INT16;
cblob_it.set_to_list (&cblobs);
box_it.set_to_list (row->blob_list ());
word_it.set_to_list (&words);
bol = TRUE;
prev_blanks = 0;
prev_fuzzy_sp = FALSE;
prev_fuzzy_non = FALSE;
if (!box_it.empty ()) {
xstarts[0] = box_it.data ()->bounding_box ().left ();
if (xstarts[0] > next_rep_char_word_right) {
/* We need to insert a repeated char word at the start of the row */
word = rep_char_it.extract ();
word_it.add_after_then_move (word);
/* Set spaces before repeated char word */
word->set_flag (W_BOL, TRUE);
bol = FALSE;
word->set_blanks (0);
//NO uncertainty
word->set_flag (W_FUZZY_SP, FALSE);
word->set_flag (W_FUZZY_NON, FALSE);
xstarts[0] = word->bounding_box ().left ();
/* Set spaces after repeated char word (and leave current word set) */
repetition_spacing = find_mean_blob_spacing (word);
current_gap = box_it.data ()->bounding_box ().left () -
next_rep_char_word_right;
current_within_xht_gap = current_gap;
if (current_gap > tosp_rep_space * repetition_spacing) {
prev_blanks = (uinT8) floor (current_gap / row->space_size);
if (prev_blanks < 1)
prev_blanks = 1;
}
else
prev_blanks = 0;
if (tosp_debug_level > 5)
tprintf ("Repch wd at BOL(%d, %d). rep spacing %5.2f; Rgap:%d ",
box_it.data ()->bounding_box ().left (),
box_it.data ()->bounding_box ().bottom (),
repetition_spacing, current_gap);
prev_fuzzy_sp = FALSE;
prev_fuzzy_non = FALSE;
if (rep_char_it.empty ()) {
next_rep_char_word_right = MAX_INT32;
}
else {
rep_char_it.forward ();
next_rep_char_word_right =
rep_char_it.data ()->bounding_box ().right ();
}
}
peek_at_next_gap(row,
box_it,
next_blob_box,
next_gap,
next_within_xht_gap);
do {
bblob = box_it.data ();
blob_box = bblob->bounding_box ();
if (bblob->joined_to_prev ()) {
if (bblob->cblob () != NULL) {
cout_it.set_to_list (cblob_it.data ()->out_list ());
cout_it.move_to_last ();
cout_it.add_list_after (bblob->cblob ()->out_list ());
delete bblob->cblob ();
}
} else {
if (bblob->cblob() != NULL)
cblob_it.add_after_then_move (bblob->cblob ());
prev_x = blob_box.right ();
}
box_it.forward (); //next one
bblob = box_it.data ();
blob_box = bblob->bounding_box ();
if (!bblob->joined_to_prev() && bblob->cblob() != NULL) {
/* Real Blob - not multiple outlines or pre-chopped */
prev_gap = current_gap;
prev_within_xht_gap = current_within_xht_gap;
prev_blob_box = next_blob_box;
current_gap = next_gap;
current_within_xht_gap = next_within_xht_gap;
peek_at_next_gap(row,
box_it,
next_blob_box,
next_gap,
next_within_xht_gap);
inT16 prev_gap_arg = prev_gap;
inT16 next_gap_arg = next_gap;
if (tosp_only_use_xht_gaps) {
prev_gap_arg = prev_within_xht_gap;
next_gap_arg = next_within_xht_gap;
}
// Decide if a word-break should be inserted
if (blob_box.left () > next_rep_char_word_right ||
make_a_word_break(row, blob_box, prev_gap_arg, prev_blob_box,
current_gap, current_within_xht_gap,
next_blob_box, next_gap_arg,
blanks, fuzzy_sp, fuzzy_non,
prev_gap_was_a_space,
break_at_next_gap) ||
box_it.at_first()) {
/* Form a new word out of the blobs collected */
word = new WERD (&cblobs, prev_blanks, NULL);
word_count++;
word_it.add_after_then_move (word);
if (bol) {
word->set_flag (W_BOL, TRUE);
bol = FALSE;
}
if (prev_fuzzy_sp)
//probably space
word->set_flag (W_FUZZY_SP, TRUE);
else if (prev_fuzzy_non)
word->set_flag (W_FUZZY_NON, TRUE);
//probably not
if (blob_box.left () > next_rep_char_word_right) {
/* We need to insert a repeated char word */
word = rep_char_it.extract ();
word_it.add_after_then_move (word);
/* Set spaces before repeated char word */
repetition_spacing = find_mean_blob_spacing (word);
current_gap = word->bounding_box ().left () - prev_x;
current_within_xht_gap = current_gap;
if (current_gap > tosp_rep_space * repetition_spacing) {
blanks =
(uinT8) floor (current_gap / row->space_size);
if (blanks < 1)
blanks = 1;
}
else
blanks = 0;
if (tosp_debug_level > 5)
tprintf
("Repch wd (%d,%d) rep gap %5.2f; Lgap:%d (%d blanks);",
word->bounding_box ().left (),
word->bounding_box ().bottom (),
repetition_spacing, current_gap, blanks);
word->set_blanks (blanks);
//NO uncertainty
word->set_flag (W_FUZZY_SP, FALSE);
word->set_flag (W_FUZZY_NON, FALSE);
/* Set spaces after repeated char word (and leave current word set) */
current_gap =
blob_box.left () - next_rep_char_word_right;
if (current_gap > tosp_rep_space * repetition_spacing) {
blanks = (uinT8) (current_gap / row->space_size);
if (blanks < 1)
blanks = 1;
}
else
blanks = 0;
if (tosp_debug_level > 5)
tprintf (" Rgap:%d (%d blanks)\n",
current_gap, blanks);
fuzzy_sp = FALSE;
fuzzy_non = FALSE;
if (rep_char_it.empty ()) {
next_rep_char_word_right = MAX_INT32;
}
else {
rep_char_it.forward ();
next_rep_char_word_right =
rep_char_it.data ()->bounding_box ().right ();
}
}
if (box_it.at_first () && rep_char_it.empty ()) {
//at end of line
word->set_flag (W_EOL, TRUE);
xstarts[1] = prev_x;
}
else {
prev_blanks = blanks;
prev_fuzzy_sp = fuzzy_sp;
prev_fuzzy_non = fuzzy_non;
}
}
}
}
while (!box_it.at_first ()); //until back at start
/* Insert any further repeated char words */
while (!rep_char_it.empty ()) {
word = rep_char_it.extract ();
word_it.add_after_then_move (word);
/* Set spaces before repeated char word */
repetition_spacing = find_mean_blob_spacing (word);
current_gap = word->bounding_box ().left () - prev_x;
if (current_gap > tosp_rep_space * repetition_spacing) {
blanks = (uinT8) floor (current_gap / row->space_size);
if (blanks < 1)
blanks = 1;
}
else
blanks = 0;
if (tosp_debug_level > 5)
tprintf(
"Repch wd at EOL (%d,%d). rep spacing %5.2f; Lgap:%d (%d blanks)\n",
word->bounding_box().left(), word->bounding_box().bottom(),
repetition_spacing, current_gap, blanks);
word->set_blanks (blanks);
//NO uncertainty
word->set_flag (W_FUZZY_SP, FALSE);
word->set_flag (W_FUZZY_NON, FALSE);
prev_x = word->bounding_box ().right ();
if (rep_char_it.empty ()) {
//at end of line
word->set_flag (W_EOL, TRUE);
xstarts[1] = prev_x;
}
else {
rep_char_it.forward ();
}
}
real_row = new ROW (row,
(inT16) row->kern_size, (inT16) row->space_size);
word_it.set_to_list (real_row->word_list ());
//put words in row
word_it.add_list_after (&words);
real_row->recalc_bounding_box ();
if (tosp_debug_level > 4) {
tprintf ("Row: Made %d words in row ((%d,%d)(%d,%d))\n",
word_count,
real_row->bounding_box ().left (),
real_row->bounding_box ().bottom (),
real_row->bounding_box ().right (),
real_row->bounding_box ().top ());
}
return real_row;
}
return NULL;
}
/**********************************************************************
* make_blob_words
*
* Converts words into blobs so that each blob is a single character.
* Used for chopper test.
**********************************************************************/
ROW *Textord::make_blob_words(
TO_ROW *row, // row to make
FCOORD rotation // for drawing
) {
bool bol; // start of line
ROW *real_row; // output row
C_OUTLINE_IT cout_it;
C_BLOB_LIST cblobs;
C_BLOB_IT cblob_it = &cblobs;
WERD_LIST words;
WERD_IT word_it; // new words
WERD *word; // new word
BLOBNBOX *bblob; // current blob
TBOX blob_box; // bounding box
BLOBNBOX_IT box_it; // iterator
inT16 word_count = 0;
cblob_it.set_to_list(&cblobs);
box_it.set_to_list(row->blob_list());
word_it.set_to_list(&words);
bol = TRUE;
if (!box_it.empty()) {
do {
bblob = box_it.data();
blob_box = bblob->bounding_box();
if (bblob->joined_to_prev()) {
if (bblob->cblob() != NULL) {
cout_it.set_to_list(cblob_it.data()->out_list());
cout_it.move_to_last();
cout_it.add_list_after(bblob->cblob()->out_list());
delete bblob->cblob();
}
} else {
if (bblob->cblob() != NULL)
cblob_it.add_after_then_move(bblob->cblob());
}
box_it.forward(); // next one
bblob = box_it.data();
blob_box = bblob->bounding_box();
if (!bblob->joined_to_prev() && !cblobs.empty()) {
word = new WERD(&cblobs, 1, NULL);
word_count++;
word_it.add_after_then_move(word);
if (bol) {
word->set_flag(W_BOL, TRUE);
bol = FALSE;
}
if (box_it.at_first()) { // at end of line
word->set_flag(W_EOL, TRUE);
}
}
}
while (!box_it.at_first()); // until back at start
/* Setup the row with created words. */
real_row = new ROW(row, (inT16) row->kern_size, (inT16) row->space_size);
word_it.set_to_list(real_row->word_list());
//put words in row
word_it.add_list_after(&words);
real_row->recalc_bounding_box();
if (tosp_debug_level > 4) {
tprintf ("Row:Made %d words in row ((%d,%d)(%d,%d))\n",
word_count,
real_row->bounding_box().left(),
real_row->bounding_box().bottom(),
real_row->bounding_box().right(),
real_row->bounding_box().top());
}
return real_row;
}
return NULL;
}
BOOL8 Textord::make_a_word_break(
TO_ROW *row, // row being made
TBOX blob_box, // for next_blob // how many blanks?
inT16 prev_gap,
TBOX prev_blob_box,
inT16 real_current_gap,
inT16 within_xht_current_gap,
TBOX next_blob_box,
inT16 next_gap,
uinT8 &blanks,
BOOL8 &fuzzy_sp,
BOOL8 &fuzzy_non,
BOOL8& prev_gap_was_a_space,
BOOL8& break_at_next_gap) {
BOOL8 space;
inT16 current_gap;
float fuzzy_sp_to_kn_limit;
if (break_at_next_gap) {
break_at_next_gap = FALSE;
return TRUE;
}
/* Inhibit using the reduced gap if
The kerning is large - chars are not kerned and reducing "f"s can cause
erroneous blanks
OR The real gap is less than 0
OR The real gap is less than the kerning estimate
*/
if ((row->kern_size > tosp_large_kerning * row->xheight) ||
((tosp_dont_fool_with_small_kerns >= 0) &&
(real_current_gap < tosp_dont_fool_with_small_kerns * row->kern_size)))
//Ignore the difference
within_xht_current_gap = real_current_gap;
if (tosp_use_xht_gaps && tosp_only_use_xht_gaps)
current_gap = within_xht_current_gap;
else
current_gap = real_current_gap;
if (tosp_old_to_method) {
//Boring old method
space = current_gap > row->max_nonspace;
if (space && (current_gap < MAX_INT16)) {
if (current_gap < row->min_space) {
if (current_gap > row->space_threshold) {
blanks = 1;
fuzzy_sp = TRUE;
fuzzy_non = FALSE;
}
else {
blanks = 0;
fuzzy_sp = FALSE;
fuzzy_non = TRUE;
}
}
else {
blanks = (uinT8) (current_gap / row->space_size);
if (blanks < 1)
blanks = 1;
fuzzy_sp = FALSE;
fuzzy_non = FALSE;
}
}
return space;
}
else {
/* New exciting heuristic method */
if (prev_blob_box.null_box ()) // Beginning of row
prev_gap_was_a_space = TRUE;
//Default as old TO
space = current_gap > row->space_threshold;
/* Set defaults for the word break incase we find one. Currently there are
no fuzzy spaces. Depending on the reliability of the different heuristics
we may need to set PARTICULAR spaces to fuzzy or not. The values will ONLY
be used if the function returns TRUE - ie the word is to be broken.
*/
blanks = (uinT8) (current_gap / row->space_size);
if (blanks < 1)
blanks = 1;
fuzzy_sp = FALSE;
fuzzy_non = FALSE;
/*
If xht measure causes gap to flip one of the 3 thresholds act accordingly -
despite any other heuristics - the MINIMUM action is to pass a fuzzy kern to
context.
*/
if (tosp_use_xht_gaps &&
(real_current_gap <= row->max_nonspace) &&
(within_xht_current_gap > row->max_nonspace)) {
space = TRUE;
fuzzy_non = TRUE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 20,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
}
else if (tosp_use_xht_gaps &&
(real_current_gap <= row->space_threshold) &&
(within_xht_current_gap > row->space_threshold)) {
space = TRUE;
if (tosp_flip_fuzz_kn_to_sp)
fuzzy_sp = TRUE;
else
fuzzy_non = TRUE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 21,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
}
else if (tosp_use_xht_gaps &&
(real_current_gap < row->min_space) &&
(within_xht_current_gap >= row->min_space)) {
space = TRUE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 22,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
}
else if (tosp_force_wordbreak_on_punct &&
!suspected_punct_blob(row, prev_blob_box) &&
suspected_punct_blob(row, blob_box)) {
break_at_next_gap = TRUE;
}
/* Now continue with normal heuristics */
else if ((current_gap < row->min_space) &&
(current_gap > row->space_threshold)) {
/* Heuristics to turn dubious spaces to kerns */
if (tosp_pass_wide_fuzz_sp_to_context > 0)
fuzzy_sp_to_kn_limit = row->kern_size +
tosp_pass_wide_fuzz_sp_to_context *
(row->space_size - row->kern_size);
else
fuzzy_sp_to_kn_limit = 99999.0f;
/* If current gap is significantly smaller than the previous space the other
side of a narrow blob then this gap is a kern. */
if ((prev_blob_box.width () > 0) &&
narrow_blob (row, prev_blob_box) &&
prev_gap_was_a_space &&
(current_gap <= tosp_gap_factor * prev_gap)) {
if ((tosp_all_flips_fuzzy) ||
(current_gap > fuzzy_sp_to_kn_limit)) {
if (tosp_flip_fuzz_sp_to_kn)
fuzzy_non = TRUE;
else
fuzzy_sp = TRUE;
}
else
space = FALSE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 1,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
}
/* If current gap not much bigger than the previous kern the other side of a
narrow blob then this gap is a kern as well */
else if ((prev_blob_box.width () > 0) &&
narrow_blob (row, prev_blob_box) &&
!prev_gap_was_a_space &&
(current_gap * tosp_gap_factor <= prev_gap)) {
if ((tosp_all_flips_fuzzy) ||
(current_gap > fuzzy_sp_to_kn_limit)) {
if (tosp_flip_fuzz_sp_to_kn)
fuzzy_non = TRUE;
else
fuzzy_sp = TRUE;
}
else
space = FALSE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 2,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
}
else if ((next_blob_box.width () > 0) &&
narrow_blob (row, next_blob_box) &&
(next_gap > row->space_threshold) &&
(current_gap <= tosp_gap_factor * next_gap)) {
if ((tosp_all_flips_fuzzy) ||
(current_gap > fuzzy_sp_to_kn_limit)) {
if (tosp_flip_fuzz_sp_to_kn)
fuzzy_non = TRUE;
else
fuzzy_sp = TRUE;
}
else
space = FALSE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 3,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
}
else if ((next_blob_box.width () > 0) &&
narrow_blob (row, next_blob_box) &&
(next_gap <= row->space_threshold) &&
(current_gap * tosp_gap_factor <= next_gap)) {
if ((tosp_all_flips_fuzzy) ||
(current_gap > fuzzy_sp_to_kn_limit)) {
if (tosp_flip_fuzz_sp_to_kn)
fuzzy_non = TRUE;
else
fuzzy_sp = TRUE;
}
else
space = FALSE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 4,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
}
else if ((((next_blob_box.width () > 0) &&
narrow_blob (row, next_blob_box)) ||
((prev_blob_box.width () > 0) &&
narrow_blob (row, prev_blob_box)))) {
fuzzy_sp = TRUE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 6,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
}
}
else if ((current_gap > row->max_nonspace) &&
(current_gap <= row->space_threshold)) {
/* Heuristics to turn dubious kerns to spaces */
/* TRIED THIS BUT IT MADE THINGS WORSE
if ( prev_gap == MAX_INT16 )
prev_gap = 0; // start of row
if ( next_gap == MAX_INT16 )
next_gap = 0; // end of row
*/
if ((prev_blob_box.width () > 0) &&
(next_blob_box.width () > 0) &&
(current_gap >=
tosp_kern_gap_factor1 * MAX (prev_gap, next_gap)) &&
wide_blob (row, prev_blob_box) &&
wide_blob (row, next_blob_box)) {
space = TRUE;
/*
tosp_flip_caution is an attempt to stop the default changing in cases
where there is a large difference between the kern and space estimates.
See problem in 'chiefs' where "have" gets split in the quotation.
*/
if ((tosp_flip_fuzz_kn_to_sp) &&
((tosp_flip_caution <= 0) ||
(tosp_flip_caution * row->kern_size > row->space_size)))
fuzzy_sp = TRUE;
else
fuzzy_non = TRUE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 7,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
} else if (prev_blob_box.width() > 0 &&
next_blob_box.width() > 0 &&
current_gap > 5 && // Rule 9 handles small gap, big ratio.
current_gap >=
tosp_kern_gap_factor2 * MAX(prev_gap, next_gap) &&
!(narrow_blob(row, prev_blob_box) ||
suspected_punct_blob(row, prev_blob_box)) &&
!(narrow_blob(row, next_blob_box) ||
suspected_punct_blob(row, next_blob_box))) {
space = TRUE;
fuzzy_non = TRUE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 8,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
}
else if ((tosp_kern_gap_factor3 > 0) &&
(prev_blob_box.width () > 0) &&
(next_blob_box.width () > 0) &&
(current_gap >= tosp_kern_gap_factor3 * MAX (prev_gap, next_gap)) &&
(!tosp_rule_9_test_punct ||
(!suspected_punct_blob (row, prev_blob_box) &&
!suspected_punct_blob (row, next_blob_box)))) {
space = TRUE;
fuzzy_non = TRUE;
#ifndef GRAPHICS_DISABLED
mark_gap (blob_box, 9,
prev_gap, prev_blob_box.width (),
current_gap, next_blob_box.width (), next_gap);
#endif
}
}
if (tosp_debug_level > 10)
tprintf("word break = %d current_gap = %d, prev_gap = %d, "
"next_gap = %d\n", space ? 1 : 0, current_gap,
prev_gap, next_gap);
prev_gap_was_a_space = space && !(fuzzy_non);
return space;
}
}
BOOL8 Textord::narrow_blob(TO_ROW *row, TBOX blob_box) {
BOOL8 result;
result = ((blob_box.width () <= tosp_narrow_fraction * row->xheight) ||
(((float) blob_box.width () / blob_box.height ()) <=
tosp_narrow_aspect_ratio));
return result;
}
BOOL8 Textord::wide_blob(TO_ROW *row, TBOX blob_box) {
BOOL8 result;
if (tosp_wide_fraction > 0) {
if (tosp_wide_aspect_ratio > 0)
result = ((blob_box.width () >= tosp_wide_fraction * row->xheight) &&
(((float) blob_box.width () / blob_box.height ()) >
tosp_wide_aspect_ratio));
else
result = (blob_box.width () >= tosp_wide_fraction * row->xheight);
}
else
result = !narrow_blob (row, blob_box);
return result;
}
BOOL8 Textord::suspected_punct_blob(TO_ROW *row, TBOX box) {
BOOL8 result;
float baseline;
float blob_x_centre;
/* Find baseline of centre of blob */
blob_x_centre = (box.right () + box.left ()) / 2.0;
baseline = row->baseline.y (blob_x_centre);
result = (box.height () <= 0.66 * row->xheight) ||
(box.top () < baseline + row->xheight / 2.0) ||
(box.bottom () > baseline + row->xheight / 2.0);
return result;
}
void Textord::peek_at_next_gap(TO_ROW *row,
BLOBNBOX_IT box_it,
TBOX &next_blob_box,
inT16 &next_gap,
inT16 &next_within_xht_gap) {
TBOX next_reduced_blob_box;
TBOX bit_beyond;
BLOBNBOX_IT reduced_box_it = box_it;
next_blob_box = box_next (&box_it);
next_reduced_blob_box = reduced_box_next (row, &reduced_box_it);
if (box_it.at_first ()) {
next_gap = MAX_INT16;
next_within_xht_gap = MAX_INT16;
}
else {
bit_beyond = box_it.data ()->bounding_box ();
next_gap = bit_beyond.left () - next_blob_box.right ();
bit_beyond = reduced_box_next (row, &reduced_box_it);
next_within_xht_gap =
bit_beyond.left () - next_reduced_blob_box.right ();
}
}
#ifndef GRAPHICS_DISABLED
void Textord::mark_gap(
TBOX blob, // blob following gap
inT16 rule, // heuristic id
inT16 prev_gap,
inT16 prev_blob_width,
inT16 current_gap,
inT16 next_blob_width,
inT16 next_gap) {
ScrollView::Color col; //of ellipse marking flipped gap
switch (rule) {
case 1:
col = ScrollView::RED;
break;
case 2:
col = ScrollView::CYAN;
break;
case 3:
col = ScrollView::GREEN;
break;
case 4:
col = ScrollView::BLACK;
break;
case 5:
col = ScrollView::MAGENTA;
break;
case 6:
col = ScrollView::BLUE;
break;
case 7:
col = ScrollView::WHITE;
break;
case 8:
col = ScrollView::YELLOW;
break;
case 9:
col = ScrollView::BLACK;
break;
case 20:
col = ScrollView::CYAN;
break;
case 21:
col = ScrollView::GREEN;
break;
case 22:
col = ScrollView::MAGENTA;
break;
default:
col = ScrollView::BLACK;
}
if (textord_show_initial_words) {
to_win->Pen(col);
/* if (rule < 20)
//interior_style(to_win, INT_SOLID, FALSE);
else
//interior_style(to_win, INT_HOLLOW, TRUE);*/
//x radius
to_win->Ellipse (current_gap / 2.0f,
blob.height () / 2.0f, //y radius
//x centre
blob.left () - current_gap / 2.0f,
//y centre
blob.bottom () + blob.height () / 2.0f);
}
if (tosp_debug_level > 5)
tprintf(" (%d,%d) Sp<->Kn Rule %d %d %d %d %d %d\n",
blob.left() - current_gap / 2, blob.bottom(), rule, prev_gap,
prev_blob_width, current_gap, next_blob_width, next_gap);
}
#endif
float Textord::find_mean_blob_spacing(WERD *word) {
C_BLOB_IT cblob_it;
TBOX blob_box;
inT32 gap_sum = 0;
inT16 gap_count = 0;
inT16 prev_right;
cblob_it.set_to_list (word->cblob_list ());
if (!cblob_it.empty ()) {
cblob_it.mark_cycle_pt ();
prev_right = cblob_it.data ()->bounding_box ().right ();
//first blob
cblob_it.forward ();
for (; !cblob_it.cycled_list (); cblob_it.forward ()) {
blob_box = cblob_it.data ()->bounding_box ();
gap_sum += blob_box.left () - prev_right;
gap_count++;
prev_right = blob_box.right ();
}
}
if (gap_count > 0)
return (gap_sum / (float) gap_count);
else
return 0.0f;
}
BOOL8 Textord::ignore_big_gap(TO_ROW *row,
inT32 row_length,
GAPMAP *gapmap,
inT16 left,
inT16 right) {
inT16 gap = right - left + 1;
if (tosp_ignore_big_gaps > 999) return FALSE; // Don't ignore
if (tosp_ignore_big_gaps > 0)
return (gap > tosp_ignore_big_gaps * row->xheight);
if (gap > tosp_ignore_very_big_gaps * row->xheight)
return TRUE;
if (tosp_ignore_big_gaps == 0) {
if ((gap > 2.1 * row->xheight) && (row_length > 20 * row->xheight))
return TRUE;
if ((gap > 1.75 * row->xheight) &&
((row_length > 35 * row->xheight) ||
gapmap->table_gap (left, right)))
return TRUE;
}
else {
/* ONLY time gaps < 3.0 * xht are ignored is when they are part of a table */
if ((gap > gapmap_big_gaps * row->xheight) &&
gapmap->table_gap (left, right))
return TRUE;
}
return FALSE;
}
/**********************************************************************
* reduced_box_next
*
* Compute the bounding box of this blob with merging of x overlaps
* but no pre-chopping.
* Then move the iterator on to the start of the next blob.
* DON'T reduce the box for small things - eg punctuation.
**********************************************************************/
TBOX Textord::reduced_box_next(
TO_ROW *row, // current row
BLOBNBOX_IT *it // iterator to blobds
) {
BLOBNBOX *blob; //current blob
BLOBNBOX *head_blob; //place to store box
TBOX full_box; //full blob boundg box
TBOX reduced_box; //box of significant part
inT16 left_above_xht; //ABOVE xht left limit
inT16 new_left_above_xht; //ABOVE xht left limit
blob = it->data ();
if (blob->red_box_set ()) {
reduced_box = blob->reduced_box ();
do {
it->forward();
blob = it->data();
}
while (blob->cblob() == NULL || blob->joined_to_prev());
return reduced_box;
}
head_blob = blob;
full_box = blob->bounding_box ();
reduced_box = reduced_box_for_blob (blob, row, &left_above_xht);
do {
it->forward ();
blob = it->data ();
if (blob->cblob() == NULL)
//was pre-chopped
full_box += blob->bounding_box ();
else if (blob->joined_to_prev ()) {
reduced_box +=
reduced_box_for_blob(blob, row, &new_left_above_xht);
left_above_xht = MIN (left_above_xht, new_left_above_xht);
}
}
//until next real blob
while (blob->cblob() == NULL || blob->joined_to_prev());
if ((reduced_box.width () > 0) &&
((reduced_box.left () + tosp_near_lh_edge * reduced_box.width ())
< left_above_xht) && (reduced_box.height () > 0.7 * row->xheight)) {
#ifndef GRAPHICS_DISABLED
if (textord_show_initial_words)
reduced_box.plot (to_win, ScrollView::YELLOW, ScrollView::YELLOW);
#endif
}
else
reduced_box = full_box;
head_blob->set_reduced_box (reduced_box);
return reduced_box;
}
/*************************************************************************
* reduced_box_for_blob()
* Find box for blob which is the same height and y position as the whole blob,
* but whose left limit is the left most position of the blob ABOVE the
* baseline and whose right limit is the right most position of the blob BELOW
* the xheight.
*
*
* !!!!!!! WONT WORK WITH LARGE UPPER CASE CHARS - T F V W - look at examples on
* "home". Perhaps we need something which say if the width ABOVE the
* xht alone includes the whole of the reduced width, then use the full
* blob box - Might still fail on italic F
*
* Alternatively we could be a little less severe and only reduce the
* left and right edges by half the difference between the full box and
* the reduced box.
*
* NOTE that we need to rotate all the coordinates as
* find_blob_limits finds the y min and max within a specified x band
*************************************************************************/
TBOX Textord::reduced_box_for_blob(
BLOBNBOX *blob,
TO_ROW *row,
inT16 *left_above_xht) {
float baseline;
float blob_x_centre;
float left_limit;
float right_limit;
float junk;
TBOX blob_box;
/* Find baseline of centre of blob */
blob_box = blob->bounding_box ();
blob_x_centre = (blob_box.left () + blob_box.right ()) / 2.0;
baseline = row->baseline.y (blob_x_centre);
/*
Find LH limit of blob ABOVE the xht. This is so that we can detect certain
caps ht chars which should NOT have their box reduced: T, Y, V, W etc
*/
left_limit = (float) MAX_INT32;
junk = (float) -MAX_INT32;
find_cblob_hlimits(blob->cblob(), (baseline + 1.1 * row->xheight),
static_cast<float>(MAX_INT16), left_limit, junk);
if (left_limit > junk)
*left_above_xht = MAX_INT16; //No area above xht
else
*left_above_xht = (inT16) floor (left_limit);
/*
Find reduced LH limit of blob - the left extent of the region ABOVE the
baseline.
*/
left_limit = (float) MAX_INT32;
junk = (float) -MAX_INT32;
find_cblob_hlimits(blob->cblob(), baseline, static_cast<float>(MAX_INT16),
left_limit, junk);
if (left_limit > junk)
return TBOX (); //no area within xht so return empty box
/*
Find reduced RH limit of blob - the right extent of the region BELOW the xht.
*/
junk = (float) MAX_INT32;
right_limit = (float) -MAX_INT32;
find_cblob_hlimits(blob->cblob(), static_cast<float>(-MAX_INT16),
(baseline + row->xheight), junk, right_limit);
if (junk > right_limit)
return TBOX (); //no area within xht so return empty box
return TBOX (ICOORD ((inT16) floor (left_limit), blob_box.bottom ()),
ICOORD ((inT16) ceil (right_limit), blob_box.top ()));
}
} // namespace tesseract