tesseract/ccmain/control.cpp
Stefan Weil 318b88daa6 ccmain: Fix typos in comments and strings
Most of them were found by codespell.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
2015-09-14 21:59:16 +02:00

2046 lines
75 KiB
C++

/******************************************************************
* File: control.cpp (Formerly control.c)
* Description: Module-independent matcher controller.
* Author: Ray Smith
* Created: Thu Apr 23 11:09:58 BST 1992
* ReHacked: Tue Sep 22 08:42:49 BST 1992 Phil Cheatle
*
* (C) Copyright 1992, Hewlett-Packard Ltd.
** 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 automatically generated configuration file if running autoconf.
#ifdef HAVE_CONFIG_H
#include "config_auto.h"
#endif
#include <string.h>
#include <math.h>
#ifdef __UNIX__
#include <assert.h>
#include <unistd.h>
#include <errno.h>
#endif
#include <ctype.h>
#include "ocrclass.h"
#include "werdit.h"
#include "drawfx.h"
#include "tessbox.h"
#include "tessvars.h"
#include "pgedit.h"
#include "reject.h"
#include "fixspace.h"
#include "docqual.h"
#include "control.h"
#include "output.h"
#include "callcpp.h"
#include "globals.h"
#include "sorthelper.h"
#include "tesseractclass.h"
#define MIN_FONT_ROW_COUNT 8
#define MAX_XHEIGHT_DIFF 3
const char* const kBackUpConfigFile = "tempconfigdata.config";
// Multiple of x-height to make a repeated word have spaces in it.
const double kRepcharGapThreshold = 0.5;
// Min believable x-height for any text when refitting as a fraction of
// original x-height
const double kMinRefitXHeightFraction = 0.5;
/**
* Make a word from the selected blobs and run Tess on them.
*
* @param page_res recognise blobs
* @param selection_box within this box
*/
namespace tesseract {
void Tesseract::recog_pseudo_word(PAGE_RES* page_res,
TBOX &selection_box) {
PAGE_RES_IT* it = make_pseudo_word(page_res, selection_box);
if (it != NULL) {
recog_interactive(it);
it->DeleteCurrentWord();
delete it;
}
}
/**
* Recognize a single word in interactive mode.
*
* @param pr_it the page results iterator
*/
BOOL8 Tesseract::recog_interactive(PAGE_RES_IT* pr_it) {
inT16 char_qual;
inT16 good_char_qual;
WordData word_data(*pr_it);
SetupWordPassN(2, &word_data);
classify_word_and_language(2, pr_it, &word_data);
if (tessedit_debug_quality_metrics) {
WERD_RES* word_res = pr_it->word();
word_char_quality(word_res, pr_it->row()->row, &char_qual, &good_char_qual);
tprintf("\n%d chars; word_blob_quality: %d; outline_errs: %d; "
"char_quality: %d; good_char_quality: %d\n",
word_res->reject_map.length(),
word_blob_quality(word_res, pr_it->row()->row),
word_outline_errs(word_res), char_qual, good_char_qual);
}
return TRUE;
}
// Helper function to check for a target word and handle it appropriately.
// Inspired by Jetsoft's requirement to process only single words on pass2
// and beyond.
// If word_config is not null:
// If the word_box and target_word_box overlap, read the word_config file
// else reset to previous config data.
// return true.
// else
// If the word_box and target_word_box overlap or pass <= 1, return true.
// Note that this function uses a fixed temporary file for storing the previous
// configs, so it is neither thread-safe, nor process-safe, but the assumption
// is that it will only be used for one debug window at a time.
//
// Since this function is used for debugging (and not to change OCR results)
// set only debug params from the word config file.
bool Tesseract::ProcessTargetWord(const TBOX& word_box,
const TBOX& target_word_box,
const char* word_config,
int pass) {
if (word_config != NULL) {
if (word_box.major_overlap(target_word_box)) {
if (backup_config_file_ == NULL) {
backup_config_file_ = kBackUpConfigFile;
FILE* config_fp = fopen(backup_config_file_, "wb");
ParamUtils::PrintParams(config_fp, params());
fclose(config_fp);
ParamUtils::ReadParamsFile(word_config,
SET_PARAM_CONSTRAINT_DEBUG_ONLY,
params());
}
} else {
if (backup_config_file_ != NULL) {
ParamUtils::ReadParamsFile(backup_config_file_,
SET_PARAM_CONSTRAINT_DEBUG_ONLY,
params());
backup_config_file_ = NULL;
}
}
} else if (pass > 1 && !word_box.major_overlap(target_word_box)) {
return false;
}
return true;
}
/** If tesseract is to be run, sets the words up ready for it. */
void Tesseract::SetupAllWordsPassN(int pass_n,
const TBOX* target_word_box,
const char* word_config,
PAGE_RES* page_res,
GenericVector<WordData>* words) {
// Prepare all the words.
PAGE_RES_IT page_res_it(page_res);
for (page_res_it.restart_page(); page_res_it.word() != NULL;
page_res_it.forward()) {
if (target_word_box == NULL ||
ProcessTargetWord(page_res_it.word()->word->bounding_box(),
*target_word_box, word_config, 1)) {
words->push_back(WordData(page_res_it));
}
}
// Setup all the words for recognition with polygonal approximation.
for (int w = 0; w < words->size(); ++w) {
SetupWordPassN(pass_n, &(*words)[w]);
if (w > 0) (*words)[w].prev_word = &(*words)[w - 1];
}
}
// Sets up the single word ready for whichever engine is to be run.
void Tesseract::SetupWordPassN(int pass_n, WordData* word) {
if (pass_n == 1 || !word->word->done) {
if (pass_n == 1) {
word->word->SetupForRecognition(unicharset, this, BestPix(),
tessedit_ocr_engine_mode, NULL,
classify_bln_numeric_mode,
textord_use_cjk_fp_model,
poly_allow_detailed_fx,
word->row, word->block);
} else if (pass_n == 2) {
// TODO(rays) Should we do this on pass1 too?
word->word->caps_height = 0.0;
if (word->word->x_height == 0.0f)
word->word->x_height = word->row->x_height();
}
word->lang_words.truncate(0);
for (int s = 0; s <= sub_langs_.size(); ++s) {
// The sub_langs_.size() entry is for the master language.
Tesseract* lang_t = s < sub_langs_.size() ? sub_langs_[s] : this;
WERD_RES* word_res = new WERD_RES;
word_res->InitForRetryRecognition(*word->word);
word->lang_words.push_back(word_res);
// Cube doesn't get setup for pass2.
if (pass_n == 1 || lang_t->tessedit_ocr_engine_mode != OEM_CUBE_ONLY) {
word_res->SetupForRecognition(
lang_t->unicharset, lang_t, BestPix(),
lang_t->tessedit_ocr_engine_mode, NULL,
lang_t->classify_bln_numeric_mode,
lang_t->textord_use_cjk_fp_model,
lang_t->poly_allow_detailed_fx, word->row, word->block);
}
}
}
}
// Runs word recognition on all the words.
bool Tesseract::RecogAllWordsPassN(int pass_n, ETEXT_DESC* monitor,
PAGE_RES_IT* pr_it,
GenericVector<WordData>* words) {
// TODO(rays) Before this loop can be parallelized (it would yield a massive
// speed-up) all remaining member globals need to be converted to local/heap
// (eg set_pass1 and set_pass2) and an intermediate adaption pass needs to be
// added. The results will be significantly different with adaption on, and
// deterioration will need investigation.
pr_it->restart_page();
for (int w = 0; w < words->size(); ++w) {
WordData* word = &(*words)[w];
if (w > 0) word->prev_word = &(*words)[w - 1];
if (monitor != NULL) {
monitor->ocr_alive = TRUE;
if (pass_n == 1)
monitor->progress = 30 + 50 * w / words->size();
else
monitor->progress = 80 + 10 * w / words->size();
if (monitor->deadline_exceeded() ||
(monitor->cancel != NULL && (*monitor->cancel)(monitor->cancel_this,
words->size()))) {
// Timeout. Fake out the rest of the words.
for (; w < words->size(); ++w) {
(*words)[w].word->SetupFake(unicharset);
}
return false;
}
}
if (word->word->tess_failed) {
int s;
for (s = 0; s < word->lang_words.size() &&
word->lang_words[s]->tess_failed; ++s) {}
// If all are failed, skip it. Image words are skipped by this test.
if (s > word->lang_words.size()) continue;
}
// Sync pr_it with the wth WordData.
while (pr_it->word() != NULL && pr_it->word() != word->word)
pr_it->forward();
ASSERT_HOST(pr_it->word() != NULL);
bool make_next_word_fuzzy = false;
if (ReassignDiacritics(pass_n, pr_it, &make_next_word_fuzzy)) {
// Needs to be setup again to see the new outlines in the chopped_word.
SetupWordPassN(pass_n, word);
}
classify_word_and_language(pass_n, pr_it, word);
if (tessedit_dump_choices || debug_noise_removal) {
tprintf("Pass%d: %s [%s]\n", pass_n,
word->word->best_choice->unichar_string().string(),
word->word->best_choice->debug_string().string());
}
pr_it->forward();
if (make_next_word_fuzzy && pr_it->word() != NULL) {
pr_it->MakeCurrentWordFuzzy();
}
}
return true;
}
/**
* recog_all_words()
*
* Walk the page_res, recognizing all the words.
* If monitor is not null, it is used as a progress monitor/timeout/cancel.
* If dopasses is 0, all recognition passes are run,
* 1 just pass 1, 2 passes2 and higher.
* If target_word_box is not null, special things are done to words that
* overlap the target_word_box:
* if word_config is not null, the word config file is read for just the
* target word(s), otherwise, on pass 2 and beyond ONLY the target words
* are processed (Jetsoft modification.)
* Returns false if we cancelled prematurely.
*
* @param page_res page structure
* @param monitor progress monitor
* @param word_config word_config file
* @param target_word_box specifies just to extract a rectangle
* @param dopasses 0 - all, 1 just pass 1, 2 passes 2 and higher
*/
bool Tesseract::recog_all_words(PAGE_RES* page_res,
ETEXT_DESC* monitor,
const TBOX* target_word_box,
const char* word_config,
int dopasses) {
PAGE_RES_IT page_res_it(page_res);
if (tessedit_minimal_rej_pass1) {
tessedit_test_adaption.set_value (TRUE);
tessedit_minimal_rejection.set_value (TRUE);
}
if (dopasses==0 || dopasses==1) {
page_res_it.restart_page();
// ****************** Pass 1 *******************
// If the adaptive classifier is full switch to one we prepared earlier,
// ie on the previous page. If the current adaptive classifier is non-empty,
// prepare a backup starting at this page, in case it fills up. Do all this
// independently for each language.
if (AdaptiveClassifierIsFull()) {
SwitchAdaptiveClassifier();
} else if (!AdaptiveClassifierIsEmpty()) {
StartBackupAdaptiveClassifier();
}
// Now check the sub-langs as well.
for (int i = 0; i < sub_langs_.size(); ++i) {
if (sub_langs_[i]->AdaptiveClassifierIsFull()) {
sub_langs_[i]->SwitchAdaptiveClassifier();
} else if (!sub_langs_[i]->AdaptiveClassifierIsEmpty()) {
sub_langs_[i]->StartBackupAdaptiveClassifier();
}
}
// Set up all words ready for recognition, so that if parallelism is on
// all the input and output classes are ready to run the classifier.
GenericVector<WordData> words;
SetupAllWordsPassN(1, target_word_box, word_config, page_res, &words);
if (tessedit_parallelize) {
PrerecAllWordsPar(words);
}
stats_.word_count = words.size();
stats_.dict_words = 0;
stats_.doc_blob_quality = 0;
stats_.doc_outline_errs = 0;
stats_.doc_char_quality = 0;
stats_.good_char_count = 0;
stats_.doc_good_char_quality = 0;
most_recently_used_ = this;
// Run pass 1 word recognition.
if (!RecogAllWordsPassN(1, monitor, &page_res_it, &words)) return false;
// Pass 1 post-processing.
for (page_res_it.restart_page(); page_res_it.word() != NULL;
page_res_it.forward()) {
if (page_res_it.word()->word->flag(W_REP_CHAR)) {
fix_rep_char(&page_res_it);
continue;
}
// Count dict words.
if (page_res_it.word()->best_choice->permuter() == USER_DAWG_PERM)
++(stats_.dict_words);
// Update misadaption log (we only need to do it on pass 1, since
// adaption only happens on this pass).
if (page_res_it.word()->blamer_bundle != NULL &&
page_res_it.word()->blamer_bundle->misadaption_debug().length() > 0) {
page_res->misadaption_log.push_back(
page_res_it.word()->blamer_bundle->misadaption_debug());
}
}
}
if (dopasses == 1) return true;
// ****************** Pass 2 *******************
if (tessedit_tess_adaption_mode != 0x0 && !tessedit_test_adaption &&
AnyTessLang()) {
page_res_it.restart_page();
GenericVector<WordData> words;
SetupAllWordsPassN(2, target_word_box, word_config, page_res, &words);
if (tessedit_parallelize) {
PrerecAllWordsPar(words);
}
most_recently_used_ = this;
// Run pass 2 word recognition.
if (!RecogAllWordsPassN(2, monitor, &page_res_it, &words)) return false;
}
// The next passes can only be run if tesseract has been used, as cube
// doesn't set all the necessary outputs in WERD_RES.
if (AnyTessLang()) {
// ****************** Pass 3 *******************
// Fix fuzzy spaces.
set_global_loc_code(LOC_FUZZY_SPACE);
if (!tessedit_test_adaption && tessedit_fix_fuzzy_spaces
&& !tessedit_word_for_word && !right_to_left())
fix_fuzzy_spaces(monitor, stats_.word_count, page_res);
// ****************** Pass 4 *******************
if (tessedit_enable_dict_correction) dictionary_correction_pass(page_res);
if (tessedit_enable_bigram_correction) bigram_correction_pass(page_res);
// ****************** Pass 5,6 *******************
rejection_passes(page_res, monitor, target_word_box, word_config);
#ifndef NO_CUBE_BUILD
// ****************** Pass 7 *******************
// Cube combiner.
// If cube is loaded and its combiner is present, run it.
if (tessedit_ocr_engine_mode == OEM_TESSERACT_CUBE_COMBINED) {
run_cube_combiner(page_res);
}
#endif
// ****************** Pass 8 *******************
font_recognition_pass(page_res);
// ****************** Pass 9 *******************
// Check the correctness of the final results.
blamer_pass(page_res);
script_pos_pass(page_res);
}
// Write results pass.
set_global_loc_code(LOC_WRITE_RESULTS);
// This is now redundant, but retained commented so show how to obtain
// bounding boxes and style information.
// changed by jetsoft
// needed for dll to output memory structure
if ((dopasses == 0 || dopasses == 2) && (monitor || tessedit_write_unlv))
output_pass(page_res_it, target_word_box);
// end jetsoft
PageSegMode pageseg_mode = static_cast<PageSegMode>(
static_cast<int>(tessedit_pageseg_mode));
textord_.CleanupSingleRowResult(pageseg_mode, page_res);
// Remove empty words, as these mess up the result iterators.
for (page_res_it.restart_page(); page_res_it.word() != NULL;
page_res_it.forward()) {
WERD_RES* word = page_res_it.word();
if (word->best_choice == NULL || word->best_choice->length() == 0)
page_res_it.DeleteCurrentWord();
}
if (monitor != NULL) {
monitor->progress = 100;
}
return true;
}
void Tesseract::bigram_correction_pass(PAGE_RES *page_res) {
PAGE_RES_IT word_it(page_res);
WERD_RES *w_prev = NULL;
WERD_RES *w = word_it.word();
while (1) {
w_prev = w;
while (word_it.forward() != NULL &&
(!word_it.word() || word_it.word()->part_of_combo)) {
// advance word_it, skipping over parts of combos
}
if (!word_it.word()) break;
w = word_it.word();
if (!w || !w_prev || w->uch_set != w_prev->uch_set) {
continue;
}
if (w_prev->word->flag(W_REP_CHAR) || w->word->flag(W_REP_CHAR)) {
if (tessedit_bigram_debug) {
tprintf("Skipping because one of the words is W_REP_CHAR\n");
}
continue;
}
// Two words sharing the same language model, excellent!
GenericVector<WERD_CHOICE *> overrides_word1;
GenericVector<WERD_CHOICE *> overrides_word2;
STRING orig_w1_str = w_prev->best_choice->unichar_string();
STRING orig_w2_str = w->best_choice->unichar_string();
WERD_CHOICE prev_best(w->uch_set);
{
int w1start, w1end;
w_prev->best_choice->GetNonSuperscriptSpan(&w1start, &w1end);
prev_best = w_prev->best_choice->shallow_copy(w1start, w1end);
}
WERD_CHOICE this_best(w->uch_set);
{
int w2start, w2end;
w->best_choice->GetNonSuperscriptSpan(&w2start, &w2end);
this_best = w->best_choice->shallow_copy(w2start, w2end);
}
if (w->tesseract->getDict().valid_bigram(prev_best, this_best)) {
if (tessedit_bigram_debug) {
tprintf("Top choice \"%s %s\" verified by bigram model.\n",
orig_w1_str.string(), orig_w2_str.string());
}
continue;
}
if (tessedit_bigram_debug > 2) {
tprintf("Examining alt choices for \"%s %s\".\n",
orig_w1_str.string(), orig_w2_str.string());
}
if (tessedit_bigram_debug > 1) {
if (!w_prev->best_choices.singleton()) {
w_prev->PrintBestChoices();
}
if (!w->best_choices.singleton()) {
w->PrintBestChoices();
}
}
float best_rating = 0.0;
int best_idx = 0;
WERD_CHOICE_IT prev_it(&w_prev->best_choices);
for (prev_it.mark_cycle_pt(); !prev_it.cycled_list(); prev_it.forward()) {
WERD_CHOICE *p1 = prev_it.data();
WERD_CHOICE strip1(w->uch_set);
{
int p1start, p1end;
p1->GetNonSuperscriptSpan(&p1start, &p1end);
strip1 = p1->shallow_copy(p1start, p1end);
}
WERD_CHOICE_IT w_it(&w->best_choices);
for (w_it.mark_cycle_pt(); !w_it.cycled_list(); w_it.forward()) {
WERD_CHOICE *p2 = w_it.data();
WERD_CHOICE strip2(w->uch_set);
{
int p2start, p2end;
p2->GetNonSuperscriptSpan(&p2start, &p2end);
strip2 = p2->shallow_copy(p2start, p2end);
}
if (w->tesseract->getDict().valid_bigram(strip1, strip2)) {
overrides_word1.push_back(p1);
overrides_word2.push_back(p2);
if (overrides_word1.size() == 1 ||
p1->rating() + p2->rating() < best_rating) {
best_rating = p1->rating() + p2->rating();
best_idx = overrides_word1.size() - 1;
}
}
}
}
if (overrides_word1.size() >= 1) {
// Excellent, we have some bigram matches.
if (EqualIgnoringCaseAndTerminalPunct(*w_prev->best_choice,
*overrides_word1[best_idx]) &&
EqualIgnoringCaseAndTerminalPunct(*w->best_choice,
*overrides_word2[best_idx])) {
if (tessedit_bigram_debug > 1) {
tprintf("Top choice \"%s %s\" verified (sans case) by bigram "
"model.\n", orig_w1_str.string(), orig_w2_str.string());
}
continue;
}
STRING new_w1_str = overrides_word1[best_idx]->unichar_string();
STRING new_w2_str = overrides_word2[best_idx]->unichar_string();
if (new_w1_str != orig_w1_str) {
w_prev->ReplaceBestChoice(overrides_word1[best_idx]);
}
if (new_w2_str != orig_w2_str) {
w->ReplaceBestChoice(overrides_word2[best_idx]);
}
if (tessedit_bigram_debug > 0) {
STRING choices_description;
int num_bigram_choices
= overrides_word1.size() * overrides_word2.size();
if (num_bigram_choices == 1) {
choices_description = "This was the unique bigram choice.";
} else {
if (tessedit_bigram_debug > 1) {
STRING bigrams_list;
const int kMaxChoicesToPrint = 20;
for (int i = 0; i < overrides_word1.size() &&
i < kMaxChoicesToPrint; i++) {
if (i > 0) { bigrams_list += ", "; }
WERD_CHOICE *p1 = overrides_word1[i];
WERD_CHOICE *p2 = overrides_word2[i];
bigrams_list += p1->unichar_string() + " " + p2->unichar_string();
if (i == kMaxChoicesToPrint) {
bigrams_list += " ...";
}
}
choices_description = "There were many choices: {";
choices_description += bigrams_list;
choices_description += "}";
} else {
choices_description.add_str_int("There were ", num_bigram_choices);
choices_description += " compatible bigrams.";
}
}
tprintf("Replaced \"%s %s\" with \"%s %s\" with bigram model. %s\n",
orig_w1_str.string(), orig_w2_str.string(),
new_w1_str.string(), new_w2_str.string(),
choices_description.string());
}
}
}
}
void Tesseract::rejection_passes(PAGE_RES* page_res,
ETEXT_DESC* monitor,
const TBOX* target_word_box,
const char* word_config) {
PAGE_RES_IT page_res_it(page_res);
// ****************** Pass 5 *******************
// Gather statistics on rejects.
int word_index = 0;
while (!tessedit_test_adaption && page_res_it.word() != NULL) {
set_global_loc_code(LOC_MM_ADAPT);
WERD_RES* word = page_res_it.word();
word_index++;
if (monitor != NULL) {
monitor->ocr_alive = TRUE;
monitor->progress = 95 + 5 * word_index / stats_.word_count;
}
if (word->rebuild_word == NULL) {
// Word was not processed by tesseract.
page_res_it.forward();
continue;
}
check_debug_pt(word, 70);
// changed by jetsoft
// specific to its needs to extract one word when need
if (target_word_box &&
!ProcessTargetWord(word->word->bounding_box(),
*target_word_box, word_config, 4)) {
page_res_it.forward();
continue;
}
// end jetsoft
page_res_it.rej_stat_word();
int chars_in_word = word->reject_map.length();
int rejects_in_word = word->reject_map.reject_count();
int blob_quality = word_blob_quality(word, page_res_it.row()->row);
stats_.doc_blob_quality += blob_quality;
int outline_errs = word_outline_errs(word);
stats_.doc_outline_errs += outline_errs;
inT16 all_char_quality;
inT16 accepted_all_char_quality;
word_char_quality(word, page_res_it.row()->row,
&all_char_quality, &accepted_all_char_quality);
stats_.doc_char_quality += all_char_quality;
uinT8 permuter_type = word->best_choice->permuter();
if ((permuter_type == SYSTEM_DAWG_PERM) ||
(permuter_type == FREQ_DAWG_PERM) ||
(permuter_type == USER_DAWG_PERM)) {
stats_.good_char_count += chars_in_word - rejects_in_word;
stats_.doc_good_char_quality += accepted_all_char_quality;
}
check_debug_pt(word, 80);
if (tessedit_reject_bad_qual_wds &&
(blob_quality == 0) && (outline_errs >= chars_in_word))
word->reject_map.rej_word_bad_quality();
check_debug_pt(word, 90);
page_res_it.forward();
}
if (tessedit_debug_quality_metrics) {
tprintf
("QUALITY: num_chs= %d num_rejs= %d %5.3f blob_qual= %d %5.3f"
" outline_errs= %d %5.3f char_qual= %d %5.3f good_ch_qual= %d %5.3f\n",
page_res->char_count, page_res->rej_count,
page_res->rej_count / static_cast<float>(page_res->char_count),
stats_.doc_blob_quality,
stats_.doc_blob_quality / static_cast<float>(page_res->char_count),
stats_.doc_outline_errs,
stats_.doc_outline_errs / static_cast<float>(page_res->char_count),
stats_.doc_char_quality,
stats_.doc_char_quality / static_cast<float>(page_res->char_count),
stats_.doc_good_char_quality,
(stats_.good_char_count > 0) ?
(stats_.doc_good_char_quality /
static_cast<float>(stats_.good_char_count)) : 0.0);
}
BOOL8 good_quality_doc =
((page_res->rej_count / static_cast<float>(page_res->char_count)) <=
quality_rej_pc) &&
(stats_.doc_blob_quality / static_cast<float>(page_res->char_count) >=
quality_blob_pc) &&
(stats_.doc_outline_errs / static_cast<float>(page_res->char_count) <=
quality_outline_pc) &&
(stats_.doc_char_quality / static_cast<float>(page_res->char_count) >=
quality_char_pc);
// ****************** Pass 6 *******************
// Do whole document or whole block rejection pass
if (!tessedit_test_adaption) {
set_global_loc_code(LOC_DOC_BLK_REJ);
quality_based_rejection(page_res_it, good_quality_doc);
}
}
void Tesseract::blamer_pass(PAGE_RES* page_res) {
if (!wordrec_run_blamer) return;
PAGE_RES_IT page_res_it(page_res);
for (page_res_it.restart_page(); page_res_it.word() != NULL;
page_res_it.forward()) {
WERD_RES *word = page_res_it.word();
BlamerBundle::LastChanceBlame(wordrec_debug_blamer, word);
page_res->blame_reasons[word->blamer_bundle->incorrect_result_reason()]++;
}
tprintf("Blame reasons:\n");
for (int bl = 0; bl < IRR_NUM_REASONS; ++bl) {
tprintf("%s %d\n", BlamerBundle::IncorrectReasonName(
static_cast<IncorrectResultReason>(bl)),
page_res->blame_reasons[bl]);
}
if (page_res->misadaption_log.length() > 0) {
tprintf("Misadaption log:\n");
for (int i = 0; i < page_res->misadaption_log.length(); ++i) {
tprintf("%s\n", page_res->misadaption_log[i].string());
}
}
}
// Sets script positions and detects smallcaps on all output words.
void Tesseract::script_pos_pass(PAGE_RES* page_res) {
PAGE_RES_IT page_res_it(page_res);
for (page_res_it.restart_page(); page_res_it.word() != NULL;
page_res_it.forward()) {
WERD_RES* word = page_res_it.word();
if (word->word->flag(W_REP_CHAR)) {
page_res_it.forward();
continue;
}
float x_height = page_res_it.block()->block->x_height();
float word_x_height = word->x_height;
if (word_x_height < word->best_choice->min_x_height() ||
word_x_height > word->best_choice->max_x_height()) {
word_x_height = (word->best_choice->min_x_height() +
word->best_choice->max_x_height()) / 2.0f;
}
// Test for small caps. Word capheight must be close to block xheight,
// and word must contain no lower case letters, and at least one upper case.
double small_cap_xheight = x_height * kXHeightCapRatio;
double small_cap_delta = (x_height - small_cap_xheight) / 2.0;
if (word->uch_set->script_has_xheight() &&
small_cap_xheight - small_cap_delta <= word_x_height &&
word_x_height <= small_cap_xheight + small_cap_delta) {
// Scan for upper/lower.
int num_upper = 0;
int num_lower = 0;
for (int i = 0; i < word->best_choice->length(); ++i) {
if (word->uch_set->get_isupper(word->best_choice->unichar_id(i)))
++num_upper;
else if (word->uch_set->get_islower(word->best_choice->unichar_id(i)))
++num_lower;
}
if (num_upper > 0 && num_lower == 0)
word->small_caps = true;
}
word->SetScriptPositions();
}
}
// Factored helper considers the indexed word and updates all the pointed
// values.
static void EvaluateWord(const PointerVector<WERD_RES>& words, int index,
float* rating, float* certainty, bool* bad,
bool* valid_permuter, int* right, int* next_left) {
*right = -MAX_INT32;
*next_left = MAX_INT32;
if (index < words.size()) {
WERD_CHOICE* choice = words[index]->best_choice;
if (choice == NULL) {
*bad = true;
} else {
*rating += choice->rating();
*certainty = MIN(*certainty, choice->certainty());
if (!Dict::valid_word_permuter(choice->permuter(), false))
*valid_permuter = false;
}
*right = words[index]->word->bounding_box().right();
if (index + 1 < words.size())
*next_left = words[index + 1]->word->bounding_box().left();
} else {
*valid_permuter = false;
*bad = true;
}
}
// Helper chooses the best combination of words, transferring good ones from
// new_words to best_words. To win, a new word must have (better rating and
// certainty) or (better permuter status and rating within rating ratio and
// certainty within certainty margin) than current best.
// All the new_words are consumed (moved to best_words or deleted.)
// The return value is the number of new_words used minus the number of
// best_words that remain in the output.
static int SelectBestWords(double rating_ratio,
double certainty_margin,
bool debug,
PointerVector<WERD_RES>* new_words,
PointerVector<WERD_RES>* best_words) {
// Process the smallest groups of words that have an overlapping word
// boundary at the end.
GenericVector<WERD_RES*> out_words;
// Index into each word vector (best, new).
int b = 0, n = 0;
int num_best = 0, num_new = 0;
while (b < best_words->size() || n < new_words->size()) {
// Start of the current run in each.
int start_b = b, start_n = n;
// Rating of the current run in each.
float b_rating = 0.0f, n_rating = 0.0f;
// Certainty of the current run in each.
float b_certainty = 0.0f, n_certainty = 0.0f;
// True if any word is missing its best choice.
bool b_bad = false, n_bad = false;
// True if all words have a valid permuter.
bool b_valid_permuter = true, n_valid_permuter = true;
while (b < best_words->size() || n < new_words->size()) {
int b_right = -MAX_INT32;
int next_b_left = MAX_INT32;
EvaluateWord(*best_words, b, &b_rating, &b_certainty, &b_bad,
&b_valid_permuter, &b_right, &next_b_left);
int n_right = -MAX_INT32;
int next_n_left = MAX_INT32;
EvaluateWord(*new_words, n, &n_rating, &n_certainty, &n_bad,
&n_valid_permuter, &n_right, &next_n_left);
if (MAX(b_right, n_right) < MIN(next_b_left, next_n_left)) {
// The word breaks overlap. [start_b,b] and [start_n, n] match.
break;
}
// Keep searching for the matching word break.
if ((b_right < n_right && b < best_words->size()) ||
n == new_words->size())
++b;
else
++n;
}
bool new_better = false;
if (!n_bad && (b_bad || (n_certainty > b_certainty &&
n_rating < b_rating) ||
(!b_valid_permuter && n_valid_permuter &&
n_rating < b_rating * rating_ratio &&
n_certainty > b_certainty - certainty_margin))) {
// New is better.
for (int i = start_n; i <= n; ++i) {
out_words.push_back((*new_words)[i]);
(*new_words)[i] = NULL;
++num_new;
}
new_better = true;
} else if (!b_bad) {
// Current best is better.
for (int i = start_b; i <= b; ++i) {
out_words.push_back((*best_words)[i]);
(*best_words)[i] = NULL;
++num_best;
}
}
int end_b = b < best_words->size() ? b + 1 : b;
int end_n = n < new_words->size() ? n + 1 : n;
if (debug) {
tprintf("%d new words %s than %d old words: r: %g v %g c: %g v %g"
" valid dict: %d v %d\n",
end_n - start_n, new_better ? "better" : "worse",
end_b - start_b, n_rating, b_rating,
n_certainty, b_certainty, n_valid_permuter, b_valid_permuter);
}
// Move on to the next group.
b = end_b;
n = end_n;
}
// Transfer from out_words to best_words.
best_words->clear();
for (int i = 0; i < out_words.size(); ++i)
best_words->push_back(out_words[i]);
return num_new - num_best;
}
// Helper to recognize the word using the given (language-specific) tesseract.
// Returns positive if this recognizer found more new best words than the
// number kept from best_words.
int Tesseract::RetryWithLanguage(const WordData& word_data,
WordRecognizer recognizer,
WERD_RES** in_word,
PointerVector<WERD_RES>* best_words) {
bool debug = classify_debug_level || cube_debug_level;
if (debug) {
tprintf("Trying word using lang %s, oem %d\n",
lang.string(), static_cast<int>(tessedit_ocr_engine_mode));
}
// Run the recognizer on the word.
PointerVector<WERD_RES> new_words;
(this->*recognizer)(word_data, in_word, &new_words);
if (new_words.empty()) {
// Transfer input word to new_words, as the classifier must have put
// the result back in the input.
new_words.push_back(*in_word);
*in_word = NULL;
}
if (debug) {
for (int i = 0; i < new_words.size(); ++i)
new_words[i]->DebugTopChoice("Lang result");
}
// Initial version is a bit of a hack based on better certainty and rating
// (to reduce false positives from cube) or a dictionary vs non-dictionary
// word.
return SelectBestWords(classify_max_rating_ratio,
classify_max_certainty_margin,
debug, &new_words, best_words);
}
// Helper returns true if all the words are acceptable.
static bool WordsAcceptable(const PointerVector<WERD_RES>& words) {
for (int w = 0; w < words.size(); ++w) {
if (words[w]->tess_failed || !words[w]->tess_accepted) return false;
}
return true;
}
// Moves good-looking "noise"/diacritics from the reject list to the main
// blob list on the current word. Returns true if anything was done, and
// sets make_next_word_fuzzy if blob(s) were added to the end of the word.
bool Tesseract::ReassignDiacritics(int pass, PAGE_RES_IT* pr_it,
bool* make_next_word_fuzzy) {
*make_next_word_fuzzy = false;
WERD* real_word = pr_it->word()->word;
if (real_word->rej_cblob_list()->empty() ||
real_word->cblob_list()->empty() ||
real_word->rej_cblob_list()->length() > noise_maxperword)
return false;
real_word->rej_cblob_list()->sort(&C_BLOB::SortByXMiddle);
// Get the noise outlines into a vector with matching bool map.
GenericVector<C_OUTLINE*> outlines;
real_word->GetNoiseOutlines(&outlines);
GenericVector<bool> word_wanted;
GenericVector<bool> overlapped_any_blob;
GenericVector<C_BLOB*> target_blobs;
AssignDiacriticsToOverlappingBlobs(outlines, pass, real_word, pr_it,
&word_wanted, &overlapped_any_blob,
&target_blobs);
// Filter the outlines that overlapped any blob and put them into the word
// now. This simplifies the remaining task and also makes it more accurate
// as it has more completed blobs to work on.
GenericVector<bool> wanted;
GenericVector<C_BLOB*> wanted_blobs;
GenericVector<C_OUTLINE*> wanted_outlines;
int num_overlapped = 0;
int num_overlapped_used = 0;
for (int i = 0; i < overlapped_any_blob.size(); ++i) {
if (overlapped_any_blob[i]) {
++num_overlapped;
if (word_wanted[i]) ++num_overlapped_used;
wanted.push_back(word_wanted[i]);
wanted_blobs.push_back(target_blobs[i]);
wanted_outlines.push_back(outlines[i]);
outlines[i] = NULL;
}
}
real_word->AddSelectedOutlines(wanted, wanted_blobs, wanted_outlines, NULL);
AssignDiacriticsToNewBlobs(outlines, pass, real_word, pr_it, &word_wanted,
&target_blobs);
int non_overlapped = 0;
int non_overlapped_used = 0;
for (int i = 0; i < word_wanted.size(); ++i) {
if (word_wanted[i]) ++non_overlapped_used;
if (outlines[i] != NULL) ++non_overlapped_used;
}
if (debug_noise_removal) {
tprintf("Used %d/%d overlapped %d/%d non-overlaped diacritics on word:",
num_overlapped_used, num_overlapped, non_overlapped_used,
non_overlapped);
real_word->bounding_box().print();
}
// Now we have decided which outlines we want, put them into the real_word.
if (real_word->AddSelectedOutlines(word_wanted, target_blobs, outlines,
make_next_word_fuzzy)) {
pr_it->MakeCurrentWordFuzzy();
}
// TODO(rays) Parts of combos have a deep copy of the real word, and need
// to have their noise outlines moved/assigned in the same way!!
return num_overlapped_used != 0 || non_overlapped_used != 0;
}
// Attempts to put noise/diacritic outlines into the blobs that they overlap.
// Input: a set of noisy outlines that probably belong to the real_word.
// Output: word_wanted indicates which outlines are to be assigned to a blob,
// target_blobs indicates which to assign to, and overlapped_any_blob is
// true for all outlines that overlapped a blob.
void Tesseract::AssignDiacriticsToOverlappingBlobs(
const GenericVector<C_OUTLINE*>& outlines, int pass, WERD* real_word,
PAGE_RES_IT* pr_it, GenericVector<bool>* word_wanted,
GenericVector<bool>* overlapped_any_blob,
GenericVector<C_BLOB*>* target_blobs) {
GenericVector<bool> blob_wanted;
word_wanted->init_to_size(outlines.size(), false);
overlapped_any_blob->init_to_size(outlines.size(), false);
target_blobs->init_to_size(outlines.size(), NULL);
// For each real blob, find the outlines that seriously overlap it.
// A single blob could be several merged characters, so there can be quite
// a few outlines overlapping, and the full engine needs to be used to chop
// and join to get a sensible result.
C_BLOB_IT blob_it(real_word->cblob_list());
for (blob_it.mark_cycle_pt(); !blob_it.cycled_list(); blob_it.forward()) {
C_BLOB* blob = blob_it.data();
TBOX blob_box = blob->bounding_box();
blob_wanted.init_to_size(outlines.size(), false);
int num_blob_outlines = 0;
for (int i = 0; i < outlines.size(); ++i) {
if (blob_box.major_x_overlap(outlines[i]->bounding_box()) &&
!(*word_wanted)[i]) {
blob_wanted[i] = true;
(*overlapped_any_blob)[i] = true;
++num_blob_outlines;
}
}
if (debug_noise_removal) {
tprintf("%d noise outlines overlap blob at:", num_blob_outlines);
blob_box.print();
}
// If any outlines overlap the blob, and not too many, classify the blob
// (using the full engine, languages and all), and choose the maximal
// combination of outlines that doesn't hurt the end-result classification
// by too much. Mark them as wanted.
if (0 < num_blob_outlines && num_blob_outlines < noise_maxperblob) {
if (SelectGoodDiacriticOutlines(pass, noise_cert_basechar, pr_it, blob,
outlines, num_blob_outlines,
&blob_wanted)) {
for (int i = 0; i < blob_wanted.size(); ++i) {
if (blob_wanted[i]) {
// Claim the outline and record where it is going.
(*word_wanted)[i] = true;
(*target_blobs)[i] = blob;
}
}
}
}
}
}
// Attempts to assign non-overlapping outlines to their nearest blobs or
// make new blobs out of them.
void Tesseract::AssignDiacriticsToNewBlobs(
const GenericVector<C_OUTLINE*>& outlines, int pass, WERD* real_word,
PAGE_RES_IT* pr_it, GenericVector<bool>* word_wanted,
GenericVector<C_BLOB*>* target_blobs) {
GenericVector<bool> blob_wanted;
word_wanted->init_to_size(outlines.size(), false);
target_blobs->init_to_size(outlines.size(), NULL);
// Check for outlines that need to be turned into stand-alone blobs.
for (int i = 0; i < outlines.size(); ++i) {
if (outlines[i] == NULL) continue;
// Get a set of adjacent outlines that don't overlap any existing blob.
blob_wanted.init_to_size(outlines.size(), false);
int num_blob_outlines = 0;
TBOX total_ol_box(outlines[i]->bounding_box());
while (i < outlines.size() && outlines[i] != NULL) {
blob_wanted[i] = true;
total_ol_box += outlines[i]->bounding_box();
++i;
++num_blob_outlines;
}
// Find the insertion point.
C_BLOB_IT blob_it(real_word->cblob_list());
while (!blob_it.at_last() &&
blob_it.data_relative(1)->bounding_box().left() <=
total_ol_box.left()) {
blob_it.forward();
}
// Choose which combination of them we actually want and where to put
// them.
if (debug_noise_removal)
tprintf("Num blobless outlines = %d\n", num_blob_outlines);
C_BLOB* left_blob = blob_it.data();
TBOX left_box = left_blob->bounding_box();
C_BLOB* right_blob = blob_it.at_last() ? NULL : blob_it.data_relative(1);
if ((left_box.x_overlap(total_ol_box) || right_blob == NULL ||
!right_blob->bounding_box().x_overlap(total_ol_box)) &&
SelectGoodDiacriticOutlines(pass, noise_cert_disjoint, pr_it, left_blob,
outlines, num_blob_outlines,
&blob_wanted)) {
if (debug_noise_removal) tprintf("Added to left blob\n");
for (int j = 0; j < blob_wanted.size(); ++j) {
if (blob_wanted[j]) {
(*word_wanted)[j] = true;
(*target_blobs)[j] = left_blob;
}
}
} else if (right_blob != NULL &&
(!left_box.x_overlap(total_ol_box) ||
right_blob->bounding_box().x_overlap(total_ol_box)) &&
SelectGoodDiacriticOutlines(pass, noise_cert_disjoint, pr_it,
right_blob, outlines,
num_blob_outlines, &blob_wanted)) {
if (debug_noise_removal) tprintf("Added to right blob\n");
for (int j = 0; j < blob_wanted.size(); ++j) {
if (blob_wanted[j]) {
(*word_wanted)[j] = true;
(*target_blobs)[j] = right_blob;
}
}
} else if (SelectGoodDiacriticOutlines(pass, noise_cert_punc, pr_it, NULL,
outlines, num_blob_outlines,
&blob_wanted)) {
if (debug_noise_removal) tprintf("Fitted between blobs\n");
for (int j = 0; j < blob_wanted.size(); ++j) {
if (blob_wanted[j]) {
(*word_wanted)[j] = true;
(*target_blobs)[j] = NULL;
}
}
}
}
}
// Starting with ok_outlines set to indicate which outlines overlap the blob,
// chooses the optimal set (approximately) and returns true if any outlines
// are desired, in which case ok_outlines indicates which ones.
bool Tesseract::SelectGoodDiacriticOutlines(
int pass, float certainty_threshold, PAGE_RES_IT* pr_it, C_BLOB* blob,
const GenericVector<C_OUTLINE*>& outlines, int num_outlines,
GenericVector<bool>* ok_outlines) {
STRING best_str;
float target_cert = certainty_threshold;
if (blob != NULL) {
float target_c2;
target_cert = ClassifyBlobAsWord(pass, pr_it, blob, &best_str, &target_c2);
if (debug_noise_removal) {
tprintf("No Noise blob classified as %s=%g(%g) at:", best_str.string(),
target_cert, target_c2);
blob->bounding_box().print();
}
target_cert -= (target_cert - certainty_threshold) * noise_cert_factor;
}
GenericVector<bool> test_outlines = *ok_outlines;
// Start with all the outlines in.
STRING all_str;
GenericVector<bool> best_outlines = *ok_outlines;
float best_cert = ClassifyBlobPlusOutlines(test_outlines, outlines, pass,
pr_it, blob, &all_str);
if (debug_noise_removal) {
TBOX ol_box;
for (int i = 0; i < test_outlines.size(); ++i) {
if (test_outlines[i]) ol_box += outlines[i]->bounding_box();
}
tprintf("All Noise blob classified as %s=%g, delta=%g at:",
all_str.string(), best_cert, best_cert - target_cert);
ol_box.print();
}
// Iteratively zero out the bit that improves the certainty the most, until
// we get past the threshold, have zero bits, or fail to improve.
int best_index = 0; // To zero out.
while (num_outlines > 1 && best_index >= 0 &&
(blob == NULL || best_cert < target_cert || blob != NULL)) {
// Find the best bit to zero out.
best_index = -1;
for (int i = 0; i < outlines.size(); ++i) {
if (test_outlines[i]) {
test_outlines[i] = false;
STRING str;
float cert = ClassifyBlobPlusOutlines(test_outlines, outlines, pass,
pr_it, blob, &str);
if (debug_noise_removal) {
TBOX ol_box;
for (int j = 0; j < outlines.size(); ++j) {
if (test_outlines[j]) ol_box += outlines[j]->bounding_box();
tprintf("%d", test_outlines[j]);
}
tprintf(" blob classified as %s=%g, delta=%g) at:", str.string(),
cert, cert - target_cert);
ol_box.print();
}
if (cert > best_cert) {
best_cert = cert;
best_index = i;
best_outlines = test_outlines;
}
test_outlines[i] = true;
}
}
if (best_index >= 0) {
test_outlines[best_index] = false;
--num_outlines;
}
}
if (best_cert >= target_cert) {
// Save the best combination.
*ok_outlines = best_outlines;
if (debug_noise_removal) {
tprintf("%s noise combination ", blob ? "Adding" : "New");
for (int i = 0; i < best_outlines.size(); ++i) {
tprintf("%d", best_outlines[i]);
}
tprintf(" yields certainty %g, beating target of %g\n", best_cert,
target_cert);
}
return true;
}
return false;
}
// Classifies the given blob plus the outlines flagged by ok_outlines, undoes
// the inclusion of the outlines, and returns the certainty of the raw choice.
float Tesseract::ClassifyBlobPlusOutlines(
const GenericVector<bool>& ok_outlines,
const GenericVector<C_OUTLINE*>& outlines, int pass_n, PAGE_RES_IT* pr_it,
C_BLOB* blob, STRING* best_str) {
C_OUTLINE_IT ol_it;
C_OUTLINE* first_to_keep = NULL;
if (blob != NULL) {
// Add the required outlines to the blob.
ol_it.set_to_list(blob->out_list());
first_to_keep = ol_it.data();
}
for (int i = 0; i < ok_outlines.size(); ++i) {
if (ok_outlines[i]) {
// This outline is to be added.
if (blob == NULL) {
blob = new C_BLOB(outlines[i]);
ol_it.set_to_list(blob->out_list());
} else {
ol_it.add_before_stay_put(outlines[i]);
}
}
}
float c2;
float cert = ClassifyBlobAsWord(pass_n, pr_it, blob, best_str, &c2);
ol_it.move_to_first();
if (first_to_keep == NULL) {
// We created blob. Empty its outlines and delete it.
for (; !ol_it.empty(); ol_it.forward()) ol_it.extract();
delete blob;
cert = -c2;
} else {
// Remove the outlines that we put in.
for (; ol_it.data() != first_to_keep; ol_it.forward()) {
ol_it.extract();
}
}
return cert;
}
// Classifies the given blob (part of word_data->word->word) as an individual
// word, using languages, chopper etc, returning only the certainty of the
// best raw choice, and undoing all the work done to fake out the word.
float Tesseract::ClassifyBlobAsWord(int pass_n, PAGE_RES_IT* pr_it,
C_BLOB* blob, STRING* best_str, float* c2) {
WERD* real_word = pr_it->word()->word;
WERD* word = real_word->ConstructFromSingleBlob(
real_word->flag(W_BOL), real_word->flag(W_EOL), C_BLOB::deep_copy(blob));
WERD_RES* word_res = pr_it->InsertSimpleCloneWord(*pr_it->word(), word);
// Get a new iterator that points to the new word.
PAGE_RES_IT it(pr_it->page_res);
while (it.word() != word_res && it.word() != NULL) it.forward();
ASSERT_HOST(it.word() == word_res);
WordData wd(it);
// Force full initialization.
SetupWordPassN(1, &wd);
classify_word_and_language(pass_n, &it, &wd);
if (debug_noise_removal) {
tprintf("word xheight=%g, row=%g, range=[%g,%g]\n", word_res->x_height,
wd.row->x_height(), wd.word->raw_choice->min_x_height(),
wd.word->raw_choice->max_x_height());
}
float cert = wd.word->raw_choice->certainty();
float rat = wd.word->raw_choice->rating();
*c2 = rat > 0.0f ? cert * cert / rat : 0.0f;
*best_str = wd.word->raw_choice->unichar_string();
it.DeleteCurrentWord();
pr_it->ResetWordIterator();
return cert;
}
// Generic function for classifying a word. Can be used either for pass1 or
// pass2 according to the function passed to recognizer.
// word_data holds the word to be recognized, and its block and row, and
// pr_it points to the word as well, in case we are running LSTM and it wants
// to output multiple words.
// Recognizes in the current language, and if successful that is all.
// If recognition was not successful, tries all available languages until
// it gets a successful result or runs out of languages. Keeps the best result.
void Tesseract::classify_word_and_language(int pass_n, PAGE_RES_IT* pr_it,
WordData* word_data) {
WordRecognizer recognizer = pass_n == 1 ? &Tesseract::classify_word_pass1
: &Tesseract::classify_word_pass2;
// Best result so far.
PointerVector<WERD_RES> best_words;
// Points to the best result. May be word or in lang_words.
WERD_RES* word = word_data->word;
clock_t start_t = clock();
if (classify_debug_level || cube_debug_level) {
tprintf("%s word with lang %s at:",
word->done ? "Already done" : "Processing",
most_recently_used_->lang.string());
word->word->bounding_box().print();
}
if (word->done) {
// If done on pass1, leave it as-is.
if (!word->tess_failed)
most_recently_used_ = word->tesseract;
return;
}
int sub = sub_langs_.size();
if (most_recently_used_ != this) {
// Get the index of the most_recently_used_.
for (sub = 0; sub < sub_langs_.size() &&
most_recently_used_ != sub_langs_[sub]; ++sub) {}
}
most_recently_used_->RetryWithLanguage(
*word_data, recognizer, &word_data->lang_words[sub], &best_words);
Tesseract* best_lang_tess = most_recently_used_;
if (!WordsAcceptable(best_words)) {
// Try all the other languages to see if they are any better.
if (most_recently_used_ != this &&
this->RetryWithLanguage(*word_data, recognizer,
&word_data->lang_words[sub_langs_.size()],
&best_words) > 0) {
best_lang_tess = this;
}
for (int i = 0; !WordsAcceptable(best_words) && i < sub_langs_.size();
++i) {
if (most_recently_used_ != sub_langs_[i] &&
sub_langs_[i]->RetryWithLanguage(*word_data, recognizer,
&word_data->lang_words[i],
&best_words) > 0) {
best_lang_tess = sub_langs_[i];
}
}
}
most_recently_used_ = best_lang_tess;
if (!best_words.empty()) {
if (best_words.size() == 1 && !best_words[0]->combination) {
// Move the best single result to the main word.
word_data->word->ConsumeWordResults(best_words[0]);
} else {
// Words came from LSTM, and must be moved to the PAGE_RES properly.
word_data->word = best_words.back();
pr_it->ReplaceCurrentWord(&best_words);
}
ASSERT_HOST(word_data->word->box_word != NULL);
} else {
tprintf("no best words!!\n");
}
clock_t ocr_t = clock();
if (tessedit_timing_debug) {
tprintf("%s (ocr took %.2f sec)\n",
word->best_choice->unichar_string().string(),
static_cast<double>(ocr_t-start_t)/CLOCKS_PER_SEC);
}
}
/**
* classify_word_pass1
*
* Baseline normalize the word and pass it to Tess.
*/
void Tesseract::classify_word_pass1(const WordData& word_data,
WERD_RES** in_word,
PointerVector<WERD_RES>* out_words) {
ROW* row = word_data.row;
BLOCK* block = word_data.block;
prev_word_best_choice_ = word_data.prev_word != NULL
? word_data.prev_word->word->best_choice : NULL;
#ifndef NO_CUBE_BUILD
// If we only intend to run cube - run it and return.
if (tessedit_ocr_engine_mode == OEM_CUBE_ONLY) {
cube_word_pass1(block, row, *in_word);
return;
}
#endif
WERD_RES* word = *in_word;
match_word_pass_n(1, word, row, block);
if (!word->tess_failed && !word->word->flag(W_REP_CHAR)) {
word->tess_would_adapt = AdaptableWord(word);
bool adapt_ok = word_adaptable(word, tessedit_tess_adaption_mode);
if (adapt_ok) {
// Send word to adaptive classifier for training.
word->BestChoiceToCorrectText();
LearnWord(NULL, word);
// Mark misadaptions if running blamer.
if (word->blamer_bundle != NULL) {
word->blamer_bundle->SetMisAdaptionDebug(word->best_choice,
wordrec_debug_blamer);
}
}
if (tessedit_enable_doc_dict && !word->IsAmbiguous())
tess_add_doc_word(word->best_choice);
}
}
// Helper to report the result of the xheight fix.
void Tesseract::ReportXhtFixResult(bool accept_new_word, float new_x_ht,
WERD_RES* word, WERD_RES* new_word) {
tprintf("New XHT Match:%s = %s ",
word->best_choice->unichar_string().string(),
word->best_choice->debug_string().string());
word->reject_map.print(debug_fp);
tprintf(" -> %s = %s ",
new_word->best_choice->unichar_string().string(),
new_word->best_choice->debug_string().string());
new_word->reject_map.print(debug_fp);
tprintf(" %s->%s %s %s\n",
word->guessed_x_ht ? "GUESS" : "CERT",
new_word->guessed_x_ht ? "GUESS" : "CERT",
new_x_ht > 0.1 ? "STILL DOUBT" : "OK",
accept_new_word ? "ACCEPTED" : "");
}
// Run the x-height fix-up, based on min/max top/bottom information in
// unicharset.
// Returns true if the word was changed.
// See the comment in fixxht.cpp for a description of the overall process.
bool Tesseract::TrainedXheightFix(WERD_RES *word, BLOCK* block, ROW *row) {
bool accept_new_x_ht = false;
int original_misfits = CountMisfitTops(word);
if (original_misfits == 0)
return false;
float baseline_shift = 0.0f;
float new_x_ht = ComputeCompatibleXheight(word, &baseline_shift);
if (baseline_shift != 0.0f) {
// Try the shift on its own first.
if (!TestNewNormalization(original_misfits, baseline_shift, word->x_height,
word, block, row))
return false;
original_misfits = CountMisfitTops(word);
if (original_misfits > 0) {
float new_baseline_shift;
// Now recompute the new x_height.
new_x_ht = ComputeCompatibleXheight(word, &new_baseline_shift);
if (new_x_ht >= kMinRefitXHeightFraction * word->x_height) {
// No test of return value here, as we are definitely making a change
// to the word by shifting the baseline.
TestNewNormalization(original_misfits, baseline_shift, new_x_ht,
word, block, row);
}
}
return true;
} else if (new_x_ht >= kMinRefitXHeightFraction * word->x_height) {
return TestNewNormalization(original_misfits, 0.0f, new_x_ht,
word, block, row);
} else {
return false;
}
}
// Runs recognition with the test baseline shift and x-height and returns true
// if there was an improvement in recognition result.
bool Tesseract::TestNewNormalization(int original_misfits,
float baseline_shift, float new_x_ht,
WERD_RES *word, BLOCK* block, ROW *row) {
bool accept_new_x_ht = false;
WERD_RES new_x_ht_word(word->word);
if (word->blamer_bundle != NULL) {
new_x_ht_word.blamer_bundle = new BlamerBundle();
new_x_ht_word.blamer_bundle->CopyTruth(*(word->blamer_bundle));
}
new_x_ht_word.x_height = new_x_ht;
new_x_ht_word.baseline_shift = baseline_shift;
new_x_ht_word.caps_height = 0.0;
new_x_ht_word.SetupForRecognition(
unicharset, this, BestPix(), tessedit_ocr_engine_mode, NULL,
classify_bln_numeric_mode, textord_use_cjk_fp_model,
poly_allow_detailed_fx, row, block);
match_word_pass_n(2, &new_x_ht_word, row, block);
if (!new_x_ht_word.tess_failed) {
int new_misfits = CountMisfitTops(&new_x_ht_word);
if (debug_x_ht_level >= 1) {
tprintf("Old misfits=%d with x-height %f, new=%d with x-height %f\n",
original_misfits, word->x_height,
new_misfits, new_x_ht);
tprintf("Old rating= %f, certainty=%f, new=%f, %f\n",
word->best_choice->rating(), word->best_choice->certainty(),
new_x_ht_word.best_choice->rating(),
new_x_ht_word.best_choice->certainty());
}
// The misfits must improve and either the rating or certainty.
accept_new_x_ht = new_misfits < original_misfits &&
(new_x_ht_word.best_choice->certainty() >
word->best_choice->certainty() ||
new_x_ht_word.best_choice->rating() <
word->best_choice->rating());
if (debug_x_ht_level >= 1) {
ReportXhtFixResult(accept_new_x_ht, new_x_ht, word, &new_x_ht_word);
}
}
if (accept_new_x_ht) {
word->ConsumeWordResults(&new_x_ht_word);
return true;
}
return false;
}
/**
* classify_word_pass2
*
* Control what to do with the word in pass 2
*/
void Tesseract::classify_word_pass2(const WordData& word_data,
WERD_RES** in_word,
PointerVector<WERD_RES>* out_words) {
// Return if we do not want to run Tesseract.
if (tessedit_ocr_engine_mode != OEM_TESSERACT_ONLY &&
tessedit_ocr_engine_mode != OEM_TESSERACT_CUBE_COMBINED &&
word_data.word->best_choice != NULL)
return;
if (tessedit_ocr_engine_mode == OEM_CUBE_ONLY) {
return;
}
ROW* row = word_data.row;
BLOCK* block = word_data.block;
WERD_RES* word = *in_word;
prev_word_best_choice_ = word_data.prev_word != NULL
? word_data.prev_word->word->best_choice : NULL;
set_global_subloc_code(SUBLOC_NORM);
check_debug_pt(word, 30);
if (!word->done) {
word->caps_height = 0.0;
if (word->x_height == 0.0f)
word->x_height = row->x_height();
match_word_pass_n(2, word, row, block);
check_debug_pt(word, 40);
}
SubAndSuperscriptFix(word);
if (!word->tess_failed && !word->word->flag(W_REP_CHAR)) {
if (unicharset.top_bottom_useful() && unicharset.script_has_xheight() &&
block->classify_rotation().y() == 0.0f) {
// Use the tops and bottoms since they are available.
TrainedXheightFix(word, block, row);
}
set_global_subloc_code(SUBLOC_NORM);
}
#ifndef GRAPHICS_DISABLED
if (tessedit_display_outwords) {
if (fx_win == NULL)
create_fx_win();
clear_fx_win();
word->rebuild_word->plot(fx_win);
TBOX wbox = word->rebuild_word->bounding_box();
fx_win->ZoomToRectangle(wbox.left(), wbox.top(),
wbox.right(), wbox.bottom());
ScrollView::Update();
}
#endif
set_global_subloc_code(SUBLOC_NORM);
check_debug_pt(word, 50);
}
/**
* match_word_pass2
*
* Baseline normalize the word and pass it to Tess.
*/
void Tesseract::match_word_pass_n(int pass_n, WERD_RES *word,
ROW *row, BLOCK* block) {
if (word->tess_failed) return;
tess_segment_pass_n(pass_n, word);
if (!word->tess_failed) {
if (!word->word->flag (W_REP_CHAR)) {
word->fix_quotes();
if (tessedit_fix_hyphens)
word->fix_hyphens();
/* Don't trust fix_quotes! - though I think I've fixed the bug */
if (word->best_choice->length() != word->box_word->length()) {
tprintf("POST FIX_QUOTES FAIL String:\"%s\"; Strlen=%d;"
" #Blobs=%d\n",
word->best_choice->debug_string().string(),
word->best_choice->length(),
word->box_word->length());
}
word->tess_accepted = tess_acceptable_word(word);
// Also sets word->done flag
make_reject_map(word, row, pass_n);
}
}
set_word_fonts(word);
ASSERT_HOST(word->raw_choice != NULL);
}
// Helper to return the best rated BLOB_CHOICE in the whole word that matches
// the given char_id, or NULL if none can be found.
static BLOB_CHOICE* FindBestMatchingChoice(UNICHAR_ID char_id,
WERD_RES* word_res) {
// Find the corresponding best BLOB_CHOICE from any position in the word_res.
BLOB_CHOICE* best_choice = NULL;
for (int i = 0; i < word_res->best_choice->length(); ++i) {
BLOB_CHOICE* choice = FindMatchingChoice(char_id,
word_res->GetBlobChoices(i));
if (choice != NULL) {
if (best_choice == NULL || choice->rating() < best_choice->rating())
best_choice = choice;
}
}
return best_choice;
}
// Helper to insert blob_choice in each location in the leader word if there is
// no matching BLOB_CHOICE there already, and correct any incorrect results
// in the best_choice.
static void CorrectRepcharChoices(BLOB_CHOICE* blob_choice,
WERD_RES* word_res) {
WERD_CHOICE* word = word_res->best_choice;
for (int i = 0; i < word_res->best_choice->length(); ++i) {
BLOB_CHOICE* choice = FindMatchingChoice(blob_choice->unichar_id(),
word_res->GetBlobChoices(i));
if (choice == NULL) {
BLOB_CHOICE_IT choice_it(word_res->GetBlobChoices(i));
choice_it.add_before_stay_put(new BLOB_CHOICE(*blob_choice));
}
}
// Correct any incorrect results in word.
for (int i = 0; i < word->length(); ++i) {
if (word->unichar_id(i) != blob_choice->unichar_id())
word->set_unichar_id(blob_choice->unichar_id(), i);
}
}
/**
* fix_rep_char()
* The word is a repeated char. (Leader.) Find the repeated char character.
* Create the appropriate single-word or multi-word sequence according to
* the size of spaces in between blobs, and correct the classifications
* where some of the characters disagree with the majority.
*/
void Tesseract::fix_rep_char(PAGE_RES_IT* page_res_it) {
WERD_RES *word_res = page_res_it->word();
const WERD_CHOICE &word = *(word_res->best_choice);
// Find the frequency of each unique character in the word.
SortHelper<UNICHAR_ID> rep_ch(word.length());
for (int i = 0; i < word.length(); ++i) {
rep_ch.Add(word.unichar_id(i), 1);
}
// Find the most frequent result.
UNICHAR_ID maxch_id = INVALID_UNICHAR_ID; // most common char
int max_count = rep_ch.MaxCount(&maxch_id);
// Find the best exemplar of a classifier result for maxch_id.
BLOB_CHOICE* best_choice = FindBestMatchingChoice(maxch_id, word_res);
if (best_choice == NULL) {
tprintf("Failed to find a choice for %s, occurring %d times\n",
word_res->uch_set->debug_str(maxch_id).string(), max_count);
return;
}
word_res->done = TRUE;
// Measure the mean space.
int gap_count = 0;
WERD* werd = word_res->word;
C_BLOB_IT blob_it(werd->cblob_list());
C_BLOB* prev_blob = blob_it.data();
for (blob_it.forward(); !blob_it.at_first(); blob_it.forward()) {
C_BLOB* blob = blob_it.data();
int gap = blob->bounding_box().left();
gap -= prev_blob->bounding_box().right();
++gap_count;
prev_blob = blob;
}
// Just correct existing classification.
CorrectRepcharChoices(best_choice, word_res);
word_res->reject_map.initialise(word.length());
}
ACCEPTABLE_WERD_TYPE Tesseract::acceptable_word_string(
const UNICHARSET& char_set, const char *s, const char *lengths) {
int i = 0;
int offset = 0;
int leading_punct_count;
int upper_count = 0;
int hyphen_pos = -1;
ACCEPTABLE_WERD_TYPE word_type = AC_UNACCEPTABLE;
if (strlen (lengths) > 20)
return word_type;
/* Single Leading punctuation char*/
if (s[offset] != '\0' && STRING(chs_leading_punct).contains(s[offset]))
offset += lengths[i++];
leading_punct_count = i;
/* Initial cap */
while (s[offset] != '\0' && char_set.get_isupper(s + offset, lengths[i])) {
offset += lengths[i++];
upper_count++;
}
if (upper_count > 1) {
word_type = AC_UPPER_CASE;
} else {
/* Lower case word, possibly with an initial cap */
while (s[offset] != '\0' && char_set.get_islower(s + offset, lengths[i])) {
offset += lengths[i++];
}
if (i - leading_punct_count < quality_min_initial_alphas_reqd)
goto not_a_word;
/*
Allow a single hyphen in a lower case word
- don't trust upper case - I've seen several cases of "H" -> "I-I"
*/
if (lengths[i] == 1 && s[offset] == '-') {
hyphen_pos = i;
offset += lengths[i++];
if (s[offset] != '\0') {
while ((s[offset] != '\0') &&
char_set.get_islower(s + offset, lengths[i])) {
offset += lengths[i++];
}
if (i < hyphen_pos + 3)
goto not_a_word;
}
} else {
/* Allow "'s" in NON hyphenated lower case words */
if (lengths[i] == 1 && (s[offset] == '\'') &&
lengths[i + 1] == 1 && (s[offset + lengths[i]] == 's')) {
offset += lengths[i++];
offset += lengths[i++];
}
}
if (upper_count > 0)
word_type = AC_INITIAL_CAP;
else
word_type = AC_LOWER_CASE;
}
/* Up to two different, constrained trailing punctuation chars */
if (lengths[i] == 1 && s[offset] != '\0' &&
STRING(chs_trailing_punct1).contains(s[offset]))
offset += lengths[i++];
if (lengths[i] == 1 && s[offset] != '\0' && i > 0 &&
s[offset - lengths[i - 1]] != s[offset] &&
STRING(chs_trailing_punct2).contains (s[offset]))
offset += lengths[i++];
if (s[offset] != '\0')
word_type = AC_UNACCEPTABLE;
not_a_word:
if (word_type == AC_UNACCEPTABLE) {
/* Look for abbreviation string */
i = 0;
offset = 0;
if (s[0] != '\0' && char_set.get_isupper(s, lengths[0])) {
word_type = AC_UC_ABBREV;
while (s[offset] != '\0' &&
char_set.get_isupper(s + offset, lengths[i]) &&
lengths[i + 1] == 1 && s[offset + lengths[i]] == '.') {
offset += lengths[i++];
offset += lengths[i++];
}
}
else if (s[0] != '\0' && char_set.get_islower(s, lengths[0])) {
word_type = AC_LC_ABBREV;
while (s[offset] != '\0' &&
char_set.get_islower(s + offset, lengths[i]) &&
lengths[i + 1] == 1 && s[offset + lengths[i]] == '.') {
offset += lengths[i++];
offset += lengths[i++];
}
}
if (s[offset] != '\0')
word_type = AC_UNACCEPTABLE;
}
return word_type;
}
BOOL8 Tesseract::check_debug_pt(WERD_RES *word, int location) {
BOOL8 show_map_detail = FALSE;
inT16 i;
if (!test_pt)
return FALSE;
tessedit_rejection_debug.set_value (FALSE);
debug_x_ht_level.set_value(0);
if (word->word->bounding_box ().contains (FCOORD (test_pt_x, test_pt_y))) {
if (location < 0)
return TRUE; // For breakpoint use
tessedit_rejection_debug.set_value (TRUE);
debug_x_ht_level.set_value(2);
tprintf ("\n\nTESTWD::");
switch (location) {
case 0:
tprintf ("classify_word_pass1 start\n");
word->word->print();
break;
case 10:
tprintf ("make_reject_map: initial map");
break;
case 20:
tprintf ("make_reject_map: after NN");
break;
case 30:
tprintf ("classify_word_pass2 - START");
break;
case 40:
tprintf ("classify_word_pass2 - Pre Xht");
break;
case 50:
tprintf ("classify_word_pass2 - END");
show_map_detail = TRUE;
break;
case 60:
tprintf ("fixspace");
break;
case 70:
tprintf ("MM pass START");
break;
case 80:
tprintf ("MM pass END");
break;
case 90:
tprintf ("After Poor quality rejection");
break;
case 100:
tprintf ("unrej_good_quality_words - START");
break;
case 110:
tprintf ("unrej_good_quality_words - END");
break;
case 120:
tprintf ("Write results pass");
show_map_detail = TRUE;
break;
}
if (word->best_choice != NULL) {
tprintf(" \"%s\" ", word->best_choice->unichar_string().string());
word->reject_map.print(debug_fp);
tprintf("\n");
if (show_map_detail) {
tprintf("\"%s\"\n", word->best_choice->unichar_string().string());
for (i = 0; word->best_choice->unichar_string()[i] != '\0'; i++) {
tprintf("**** \"%c\" ****\n", word->best_choice->unichar_string()[i]);
word->reject_map[i].full_print(debug_fp);
}
}
} else {
tprintf("null best choice\n");
}
tprintf ("Tess Accepted: %s\n", word->tess_accepted ? "TRUE" : "FALSE");
tprintf ("Done flag: %s\n\n", word->done ? "TRUE" : "FALSE");
return TRUE;
} else {
return FALSE;
}
}
/**
* find_modal_font
*
* Find the modal font and remove from the stats.
*/
static void find_modal_font( //good chars in word
STATS *fonts, //font stats
inT16 *font_out, //output font
inT8 *font_count //output count
) {
inT16 font; //font index
inT32 count; //pile couat
if (fonts->get_total () > 0) {
font = (inT16) fonts->mode ();
*font_out = font;
count = fonts->pile_count (font);
*font_count = count < MAX_INT8 ? count : MAX_INT8;
fonts->add (font, -*font_count);
}
else {
*font_out = -1;
*font_count = 0;
}
}
/**
* set_word_fonts
*
* Get the fonts for the word.
*/
void Tesseract::set_word_fonts(WERD_RES *word) {
// Don't try to set the word fonts for a cube word, as the configs
// will be meaningless.
if (word->chopped_word == NULL) return;
ASSERT_HOST(word->best_choice != NULL);
int fontinfo_size = get_fontinfo_table().size();
if (fontinfo_size == 0) return;
GenericVector<int> font_total_score;
font_total_score.init_to_size(fontinfo_size, 0);
word->italic = 0;
word->bold = 0;
// Compute the font scores for the word
if (tessedit_debug_fonts) {
tprintf("Examining fonts in %s\n",
word->best_choice->debug_string().string());
}
for (int b = 0; b < word->best_choice->length(); ++b) {
BLOB_CHOICE* choice = word->GetBlobChoice(b);
if (choice == NULL) continue;
const GenericVector<ScoredFont>& fonts = choice->fonts();
for (int f = 0; f < fonts.size(); ++f) {
int fontinfo_id = fonts[f].fontinfo_id;
if (0 <= fontinfo_id && fontinfo_id < fontinfo_size) {
font_total_score[fontinfo_id] += fonts[f].score;
}
}
}
// Find the top and 2nd choice for the word.
int score1 = 0, score2 = 0;
inT16 font_id1 = -1, font_id2 = -1;
for (int f = 0; f < fontinfo_size; ++f) {
if (tessedit_debug_fonts && font_total_score[f] > 0) {
tprintf("Font %s, total score = %d\n",
fontinfo_table_.get(f).name, font_total_score[f]);
}
if (font_total_score[f] > score1) {
score2 = score1;
font_id2 = font_id1;
score1 = font_total_score[f];
font_id1 = f;
} else if (font_total_score[f] > score2) {
score2 = font_total_score[f];
font_id2 = f;
}
}
word->fontinfo = font_id1 >= 0 ? &fontinfo_table_.get(font_id1) : NULL;
word->fontinfo2 = font_id2 >= 0 ? &fontinfo_table_.get(font_id2) : NULL;
// Each score has a limit of MAX_UINT16, so divide by that to get the number
// of "votes" for that font, ie number of perfect scores.
word->fontinfo_id_count = ClipToRange(score1 / MAX_UINT16, 1, MAX_INT8);
word->fontinfo_id2_count = ClipToRange(score2 / MAX_UINT16, 0, MAX_INT8);
if (score1 > 0) {
FontInfo fi = fontinfo_table_.get(font_id1);
if (tessedit_debug_fonts) {
if (word->fontinfo_id2_count > 0) {
tprintf("Word modal font=%s, score=%d, 2nd choice %s/%d\n",
fi.name, word->fontinfo_id_count,
fontinfo_table_.get(font_id2).name,
word->fontinfo_id2_count);
} else {
tprintf("Word modal font=%s, score=%d. No 2nd choice\n",
fi.name, word->fontinfo_id_count);
}
}
word->italic = (fi.is_italic() ? 1 : -1) * word->fontinfo_id_count;
word->bold = (fi.is_bold() ? 1 : -1) * word->fontinfo_id_count;
}
}
/**
* font_recognition_pass
*
* Smooth the fonts for the document.
*/
void Tesseract::font_recognition_pass(PAGE_RES* page_res) {
PAGE_RES_IT page_res_it(page_res);
WERD_RES *word; // current word
STATS doc_fonts(0, font_table_size_); // font counters
// Gather font id statistics.
for (page_res_it.restart_page(); page_res_it.word() != NULL;
page_res_it.forward()) {
word = page_res_it.word();
if (word->fontinfo != NULL) {
doc_fonts.add(word->fontinfo->universal_id, word->fontinfo_id_count);
}
if (word->fontinfo2 != NULL) {
doc_fonts.add(word->fontinfo2->universal_id, word->fontinfo_id2_count);
}
}
inT16 doc_font; // modal font
inT8 doc_font_count; // modal font
find_modal_font(&doc_fonts, &doc_font, &doc_font_count);
if (doc_font_count == 0)
return;
// Get the modal font pointer.
const FontInfo* modal_font = NULL;
for (page_res_it.restart_page(); page_res_it.word() != NULL;
page_res_it.forward()) {
word = page_res_it.word();
if (word->fontinfo != NULL && word->fontinfo->universal_id == doc_font) {
modal_font = word->fontinfo;
break;
}
if (word->fontinfo2 != NULL && word->fontinfo2->universal_id == doc_font) {
modal_font = word->fontinfo2;
break;
}
}
ASSERT_HOST(modal_font != NULL);
// Assign modal font to weak words.
for (page_res_it.restart_page(); page_res_it.word() != NULL;
page_res_it.forward()) {
word = page_res_it.word();
int length = word->best_choice->length();
int count = word->fontinfo_id_count;
if (!(count == length || (length > 3 && count >= length * 3 / 4))) {
word->fontinfo = modal_font;
// Counts only get 1 as it came from the doc.
word->fontinfo_id_count = 1;
word->italic = modal_font->is_italic() ? 1 : -1;
word->bold = modal_font->is_bold() ? 1 : -1;
}
}
}
// If a word has multiple alternates check if the best choice is in the
// dictionary. If not, replace it with an alternate that exists in the
// dictionary.
void Tesseract::dictionary_correction_pass(PAGE_RES *page_res) {
PAGE_RES_IT word_it(page_res);
for (WERD_RES* word = word_it.word(); word != NULL;
word = word_it.forward()) {
if (word->best_choices.singleton())
continue; // There are no alternates.
WERD_CHOICE* best = word->best_choice;
if (word->tesseract->getDict().valid_word(*best) != 0)
continue; // The best choice is in the dictionary.
WERD_CHOICE_IT choice_it(&word->best_choices);
for (choice_it.mark_cycle_pt(); !choice_it.cycled_list();
choice_it.forward()) {
WERD_CHOICE* alternate = choice_it.data();
if (word->tesseract->getDict().valid_word(*alternate)) {
// The alternate choice is in the dictionary.
if (tessedit_bigram_debug) {
tprintf("Dictionary correction replaces best choice '%s' with '%s'\n",
best->unichar_string().string(),
alternate->unichar_string().string());
}
// Replace the 'best' choice with a better choice.
word->ReplaceBestChoice(alternate);
break;
}
}
}
}
} // namespace tesseract