tesseract/src/wordrec/lm_pain_points.cpp

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///////////////////////////////////////////////////////////////////////
// File: pain_points.cpp
// Description: Functions that utilize the knowledge about the properties
// of the paths explored by the segmentation search in order
// to "pain points" - the locations in the ratings matrix
// which should be classified next.
// Author: Rika Antonova
// Created: Mon Jun 20 11:26:43 PST 2012
//
// (C) Copyright 2012, Google Inc.
// 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.
//
///////////////////////////////////////////////////////////////////////
#include "lm_pain_points.h"
#include "associate.h"
#include "dict.h"
#include "genericheap.h"
#include "lm_state.h"
#include "matrix.h"
#include "pageres.h"
#include <algorithm>
namespace tesseract {
const float LMPainPoints::kDefaultPainPointPriorityAdjustment = 2.0f;
const float LMPainPoints::kLooseMaxCharWhRatio = 2.5f;
LMPainPointsType LMPainPoints::Deque(MATRIX_COORD *pp, float *priority) {
for (int h = 0; h < LM_PPTYPE_NUM; ++h) {
if (pain_points_heaps_[h].empty()) continue;
*priority = pain_points_heaps_[h].PeekTop().key;
*pp = pain_points_heaps_[h].PeekTop().data;
pain_points_heaps_[h].Pop(nullptr);
return static_cast<LMPainPointsType>(h);
}
return LM_PPTYPE_NUM;
}
void LMPainPoints::GenerateInitial(WERD_RES *word_res) {
MATRIX *ratings = word_res->ratings;
AssociateStats associate_stats;
for (int col = 0; col < ratings->dimension(); ++col) {
int row_end = std::min(ratings->dimension(), col + ratings->bandwidth() + 1);
for (int row = col + 1; row < row_end; ++row) {
MATRIX_COORD coord(col, row);
if (coord.Valid(*ratings) &&
ratings->get(col, row) != NOT_CLASSIFIED) continue;
// Add an initial pain point if needed.
if (ratings->Classified(col, row - 1, dict_->WildcardID()) ||
(col + 1 < ratings->dimension() &&
ratings->Classified(col + 1, row, dict_->WildcardID()))) {
GeneratePainPoint(col, row, LM_PPTYPE_SHAPE, 0.0,
true, max_char_wh_ratio_, word_res);
}
}
}
}
void LMPainPoints::GenerateFromPath(float rating_cert_scale,
ViterbiStateEntry *vse,
WERD_RES *word_res) {
ViterbiStateEntry *curr_vse = vse;
BLOB_CHOICE *curr_b = vse->curr_b;
// The following pain point generation and priority calculation approaches
// prioritize exploring paths with low average rating of the known part of
// the path, while not relying on the ratings of the pieces to be combined.
//
// A pain point to combine the neighbors is generated for each pair of
// neighboring blobs on the path (the path is represented by vse argument
// given to GenerateFromPath()). The priority of each pain point is set to
// the average rating (per outline length) of the path, not including the
// ratings of the blobs to be combined.
// The ratings of the blobs to be combined are not used to calculate the
// priority, since it is not possible to determine from their magnitude
// whether it will be beneficial to combine the blobs. The reason is that
// chopped junk blobs (/ | - ') can have very good (low) ratings, however
// combining them will be beneficial. Blobs with high ratings might be
// over-joined pieces of characters, but also could be blobs from an unseen
// font or chopped pieces of complex characters.
while (curr_vse->parent_vse != nullptr) {
ViterbiStateEntry* parent_vse = curr_vse->parent_vse;
const MATRIX_COORD& curr_cell = curr_b->matrix_cell();
const MATRIX_COORD& parent_cell = parent_vse->curr_b->matrix_cell();
MATRIX_COORD pain_coord(parent_cell.col, curr_cell.row);
if (!pain_coord.Valid(*word_res->ratings) ||
!word_res->ratings->Classified(parent_cell.col, curr_cell.row,
dict_->WildcardID())) {
// rat_subtr contains ratings sum of the two adjacent blobs to be merged.
// rat_subtr will be subtracted from the ratings sum of the path, since
// the blobs will be joined into a new blob, whose rating is yet unknown.
float rat_subtr = curr_b->rating() + parent_vse->curr_b->rating();
// ol_subtr contains the outline length of the blobs that will be joined.
float ol_subtr =
AssociateUtils::ComputeOutlineLength(rating_cert_scale, *curr_b) +
AssociateUtils::ComputeOutlineLength(rating_cert_scale,
*(parent_vse->curr_b));
// ol_dif is the outline of the path without the two blobs to be joined.
float ol_dif = vse->outline_length - ol_subtr;
// priority is set to the average rating of the path per unit of outline,
// not counting the ratings of the pieces to be joined.
float priority = ol_dif > 0 ? (vse->ratings_sum-rat_subtr)/ol_dif : 0.0;
GeneratePainPoint(pain_coord.col, pain_coord.row, LM_PPTYPE_PATH,
priority, true, max_char_wh_ratio_, word_res);
} else if (debug_level_ > 3) {
tprintf("NO pain point (Classified) for col=%d row=%d type=%s\n",
pain_coord.col, pain_coord.row,
LMPainPointsTypeName[LM_PPTYPE_PATH]);
BLOB_CHOICE_IT b_it(word_res->ratings->get(pain_coord.col,
pain_coord.row));
for (b_it.mark_cycle_pt(); !b_it.cycled_list(); b_it.forward()) {
BLOB_CHOICE* choice = b_it.data();
choice->print_full();
}
}
curr_vse = parent_vse;
curr_b = curr_vse->curr_b;
}
}
void LMPainPoints::GenerateFromAmbigs(const DANGERR &fixpt,
ViterbiStateEntry *vse,
WERD_RES *word_res) {
// Begins and ends in DANGERR vector now record the blob indices as used
// by the ratings matrix.
for (int d = 0; d < fixpt.size(); ++d) {
const DANGERR_INFO &danger = fixpt[d];
// Only use dangerous ambiguities.
if (danger.dangerous) {
GeneratePainPoint(danger.begin, danger.end - 1,
LM_PPTYPE_AMBIG, vse->cost, true,
kLooseMaxCharWhRatio, word_res);
}
}
}
bool LMPainPoints::GeneratePainPoint(
int col, int row, LMPainPointsType pp_type, float special_priority,
bool ok_to_extend, float max_char_wh_ratio,
WERD_RES *word_res) {
MATRIX_COORD coord(col, row);
if (coord.Valid(*word_res->ratings) &&
word_res->ratings->Classified(col, row, dict_->WildcardID())) {
return false;
}
if (debug_level_ > 3) {
tprintf("Generating pain point for col=%d row=%d type=%s\n",
col, row, LMPainPointsTypeName[pp_type]);
}
// Compute associate stats.
AssociateStats associate_stats;
AssociateUtils::ComputeStats(col, row, nullptr, 0, fixed_pitch_,
max_char_wh_ratio, word_res, debug_level_,
&associate_stats);
// For fixed-pitch fonts/languages: if the current combined blob overlaps
// the next blob on the right and it is ok to extend the blob, try extending
// the blob until there is no overlap with the next blob on the right or
// until the width-to-height ratio becomes too large.
if (ok_to_extend) {
while (associate_stats.bad_fixed_pitch_right_gap &&
row + 1 < word_res->ratings->dimension() &&
!associate_stats.bad_fixed_pitch_wh_ratio) {
AssociateUtils::ComputeStats(col, ++row, nullptr, 0, fixed_pitch_,
max_char_wh_ratio, word_res, debug_level_,
&associate_stats);
}
}
if (associate_stats.bad_shape) {
if (debug_level_ > 3) {
tprintf("Discarded pain point with a bad shape\n");
}
return false;
}
// Insert the new pain point into pain_points_heap_.
if (pain_points_heaps_[pp_type].size() < max_heap_size_) {
// Compute pain point priority.
float priority;
if (pp_type == LM_PPTYPE_PATH) {
priority = special_priority;
} else {
priority = associate_stats.gap_sum;
}
MatrixCoordPair pain_point(priority, MATRIX_COORD(col, row));
pain_points_heaps_[pp_type].Push(&pain_point);
if (debug_level_) {
tprintf("Added pain point with priority %g\n", priority);
}
return true;
} else {
if (debug_level_) tprintf("Pain points heap is full\n");
return false;
}
}
Doxygen Squashed commit from https://github.com/tesseract-ocr/tesseract/tree/more-doxygen closes #14 Commits: 6317305 doxygen 9f42f69 doxygen 0fc4d52 doxygen 37b4b55 fix typo bded8f1 some more doxy 020eb00 slight tweak 524666d doxygenify 2a36a3e doxygenify 229d218 doxygenify 7fd28ae doxygenify a8c64bc doxygenify f5d21b6 fix 5d8ede8 doxygenify a58a4e0 language_model.cpp fa85709 lm_pain_points.cpp lm_state.cpp 6418da3 merge 06190ba Merge branch 'old_doxygen_merge' into more-doxygen 84acf08 Merge branch 'master' into more-doxygen 50fe1ff pagewalk.cpp cube_reco_context.cpp 2982583 change to relative 192a24a applybox.cpp, take one 8eeb053 delete docs for obsolete params 52e4c77 modernise classify/ocrfeatures.cpp 2a1cba6 modernise cutil/emalloc.cpp 773e006 silence doxygen warning aeb1731 silence doxygen warning f18387f silence doxygen; new params are unused? 15ad6bd doxygenify cutil/efio.cpp c8b5dad doxygenify cutil/danerror.cpp 784450f the globals and exceptions parts are obsolete; remove 8bca324 doxygen classify/normfeat.cpp 9bcbe16 doxygen classify/normmatch.cpp aa9a971 doxygen ccmain/cube_control.cpp c083ff2 doxygen ccmain/cube_reco_context.cpp f842850 params changed 5c94f12 doxygen ccmain/cubeclassifier.cpp 15ba750 case sensitive f5c71d4 case sensitive f85655b doxygen classify/intproto.cpp 4bbc7aa partial doxygen classify/mfx.cpp dbb6041 partial doxygen classify/intproto.cpp 2aa72db finish doxygen classify/intproto.cpp 0b8de99 doxygen training/mftraining.cpp 0b5b35c partial doxygen ccstruct/coutln.cpp b81c766 partial doxygen ccstruct/coutln.cpp 40fc415 finished? doxygen ccstruct/coutln.cpp 6e4165c doxygen classify/clusttool.cpp 0267dec doxygen classify/cutoffs.cpp 7f0c70c doxygen classify/fpoint.cpp 512f3bd ignore ~ files 5668a52 doxygen classify/intmatcher.cpp 84788d4 doxygen classify/kdtree.cpp 29f36ca doxygen classify/mfoutline.cpp 40b94b1 silence doxygen warnings 6c511b9 doxygen classify/mfx.cpp f9b4080 doxygen classify/outfeat.cpp aa1df05 doxygen classify/picofeat.cpp cc5f466 doxygen training/cntraining.cpp cce044f doxygen training/commontraining.cpp 167e216 missing param 9498383 renamed params 37eeac2 renamed param d87b5dd case c8ee174 renamed params b858db8 typo 4c2a838 h2 context? 81a2c0c fix some param names; add some missing params, no docs bcf8a4c add some missing params, no docs af77f86 add some missing params, no docs; fix some param names 01df24e fix some params 6161056 fix some params 68508b6 fix some params 285aeb6 doxygen complains here no matter what 529bcfa rm some missing params, typos cd21226 rm some missing params, add some new ones 48a4bc2 fix params c844628 missing param 312ce37 missing param; rename one ec2fdec missing param 05e15e0 missing params d515858 change "<" to &lt; to make doxygen happy b476a28 wrong place
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/**
* Adjusts the pain point coordinates to cope with expansion of the ratings
* matrix due to a split of the blob with the given index.
*/
void LMPainPoints::RemapForSplit(int index) {
for (auto & pain_points_heap : pain_points_heaps_) {
GenericVector<MatrixCoordPair>* heap = pain_points_heap.heap();
for (int j = 0; j < heap->size(); ++j)
(*heap)[j].data.MapForSplit(index);
}
}
} // namespace tesseract