/* -*-C-*- ******************************************************************************** * * File: permute.c (Formerly permute.c) * Description: Choose OCR text given character-probability maps * for sequences of glyph fragments and a dictionary provided as * a Dual Acyclic Word Graph. * In this file, "permute" should be read "combine." * Author: Mark Seaman, OCR Technology * Created: Fri Sep 22 14:05:51 1989 * Modified: Thu Jan 3 16:38:46 1991 (Mark Seaman) marks@hpgrlt * Language: C * Package: N/A * Status: Experimental (Do Not Distribute) * * (c) Copyright 1989, Hewlett-Packard Company. ** 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. * *********************************************************************************/ /*---------------------------------------------------------------------- I n c l u d e s ---------------------------------------------------------------------*/ #ifdef _MSC_VER #pragma warning(disable:4244) // Conversion warnings #pragma warning(disable:4800) // int/bool warnings #endif #include #include #include "const.h" #include "permute.h" #include "callcpp.h" #include "ccutil.h" #include "dict.h" #include "freelist.h" #include "helpers.h" #include "image.h" #include "globals.h" #include "ndminx.h" #include "ratngs.h" #include "stopper.h" #include "tprintf.h" #include "trie.h" #include "params.h" #include "unicharset.h" namespace tesseract { /*---------------------------------------------------------------------- F u n c t i o n s ----------------------------------------------------------------------*/ /** * get_best_delete_other * * Returns the best of two choices and deletes the other (worse) choice. * A choice is better if it has a non-empty string and has a lower * rating than the other choice. If the ratings are the same, * choice2 is preferred over choice1. */ WERD_CHOICE *get_best_delete_other(WERD_CHOICE *choice1, WERD_CHOICE *choice2) { if (!choice1) return choice2; if (!choice2) return choice1; if (choice1->rating() < choice2->rating() || choice2->length() == 0) { delete choice2; return choice1; } else { delete choice1; return choice2; } } /** * Returns the n-th choice in the given blob_list (top-K choices). * If n > K, the last choice is returned. */ BLOB_CHOICE* get_nth_choice(BLOB_CHOICE_LIST* blob_list, int n) { BLOB_CHOICE_IT c_it(blob_list); while (n-- > 0 && !c_it.at_last()) c_it.forward(); return c_it.data(); } /** Returns the top choice char id. A helper function to make code cleaner. */ UNICHAR_ID get_top_choice_uid(BLOB_CHOICE_LIST *blob_list) { if (!blob_list) return INVALID_UNICHAR_ID; BLOB_CHOICE_IT blob_choice_it(blob_list); return (blob_choice_it.data()) ? blob_choice_it.data()->unichar_id() : INVALID_UNICHAR_ID; } /** * Returns the rank (starting at 0) of a given unichar ID in the char * choice list, or -1 if not found. */ int find_choice_by_uid(BLOB_CHOICE_LIST *blob_list, UNICHAR_ID target_uid) { BLOB_CHOICE_IT c_it(blob_list); int pos = 0; while (1) { if (c_it.data()->unichar_id() == target_uid) return pos; if (c_it.at_last()) break; c_it.forward(); pos++; } return -1; } /** * Returns a WERD formed by taking the specified position (nth choice) string * from char_choices starting at the given position. * For example, if start_pos=2, pos_str="0121" will form a word using the * 1st choice of char 3, 2nd choice of char 4, 3rd choice of char 5, 2nd choice * of char 6. If n > number of choice, the closest (last) one is used. */ WERD_CHOICE* get_choice_from_posstr(const UNICHARSET *unicharset, const BLOB_CHOICE_LIST_VECTOR &char_choices, int start_pos, const char* pos_str, float *certainties) { int pos_str_len = strlen(pos_str); WERD_CHOICE* wchoice = new WERD_CHOICE(unicharset); if (start_pos + pos_str_len > char_choices.length()) { wchoice->make_bad(); return wchoice; } for (int x = 0; x < pos_str_len; x++) { int pos = pos_str[x]-'0'; if (pos < 0) pos = 0; // use the top choice by default, eg. '.' if (pos >= 10) tprintf("PosStr[%d](%d)=%c %d\n", x, pos_str_len, pos_str[x], pos); ASSERT_HOST(pos < 10); BLOB_CHOICE* blob_it = get_nth_choice(char_choices.get(start_pos+x), pos); wchoice->set_permuter(NO_PERM); wchoice->append_unichar_id(blob_it->unichar_id(), 1, blob_it->rating(), blob_it->certainty()); if (certainties != NULL) certainties[x] = blob_it->certainty(); } return wchoice; } /** * Given a WERD_CHOICE, find the corresponding position string from * char_choices. Pos_str must have been allocated already. * This is the reverse of get_choice_from_posstr. */ void get_posstr_from_choice(const BLOB_CHOICE_LIST_VECTOR &char_choices, WERD_CHOICE* word_choice, int start_pos, char* pos_str) { for (int i = 0; i < word_choice->length(); i++) { UNICHAR_ID target_id = word_choice->unichar_id(i); BLOB_CHOICE_LIST* blob_choice_list = char_choices.get(start_pos + i); int pos = find_choice_by_uid(blob_choice_list, target_id); if (pos < 0) pos = 0; pos_str[i] = pos + '0'; } pos_str[word_choice->length()] = '\0'; } /** * Iterate through all the character choices (for a single blob) and * return the first that matches the given type, which is one of 'aA0px*', * for lower, upper, digit, punctuation, other, and 'any', respectively. * If not match is found, a NULL is returned. */ BLOB_CHOICE* find_choice_by_type( BLOB_CHOICE_LIST *blob_choices, char target_type, const UNICHARSET &unicharset) { BLOB_CHOICE_IT c_it(blob_choices); for (c_it.mark_cycle_pt(); !c_it.cycled_list(); c_it.forward()) { if (c_it.data() && unicharset.get_chartype(c_it.data()->unichar_id()) == target_type) return c_it.data(); } return NULL; } /** * Iterate through all the character choices (for a single blob) and * return the first that matches the target script ID. If backup_sid * is not 0, then a match on either the target or backup sid is allowed. * Note that there is no preference between a target or backup sid. * To search for another sid only if no target_sid matched, use * secondary_sid. * So for example, to find first Han or Common char choice, do * find_choice_by_script(cchoice, han_sid, common_sid, 0); * To find first Han choice, but allow Common if none is found, do * find_choice_by_script(cchoice, han_sid, 0, common_sid); */ BLOB_CHOICE* find_choice_by_script( BLOB_CHOICE_LIST *blob_choices, int target_sid, int backup_sid, int secondary_sid) { BLOB_CHOICE_IT c_it(blob_choices); for (c_it.mark_cycle_pt(); !c_it.cycled_list(); c_it.forward()) { bool found = false; if (c_it.data()->script_id() == 0) continue; if (c_it.data()->script_id() == target_sid) found = true; if (backup_sid > 0 && c_it.data()->script_id() == backup_sid) found = true; if (found) return c_it.data(); } if (secondary_sid > 0) { c_it.set_to_list(blob_choices); for (c_it.mark_cycle_pt(); !c_it.cycled_list(); c_it.forward()) { if (c_it.data()->script_id() == 0) continue; if (c_it.data()->script_id() == secondary_sid) return c_it.data(); } } return NULL; } PermuterState::PermuterState() { unicharset_ = NULL; char_choices_ = NULL; adjust_factor_ = 1.0f; allow_collision_ = false; word_length_ = 0; debug_ = false; } void PermuterState::Init(const BLOB_CHOICE_LIST_VECTOR& char_choices, const UNICHARSET& unicharset, float default_bias, bool debug) { ASSERT_HOST(char_choices.length() < MAX_PERM_LENGTH); unicharset_ = &unicharset; char_choices_ = &char_choices; word_length_ = char_choices.length(); for (int i = 0; i < word_length_; ++i) perm_state_[i] = kPosFree; perm_state_[word_length_] = '\0'; // Skip fragment choice and the mark positions so they remain unchanged. for (int i = 0; i < word_length_; ++i) { UNICHAR_ID unichar_id = get_top_choice_uid(char_choices.get(i)); if (unicharset.get_fragment(unichar_id) != NULL) perm_state_[i] = '1'; } adjust_factor_ = default_bias; allow_collision_ = false; debug_ = debug; } // Promote char positions specified in pos_str with given weight. // For example, AddPreference(5, "234", 0.95f) // would promote the 3rd, 4th and 5th choice for character 5, 6, 7 // (starting at 0) in the word with a rating adjustment of 0.95. void PermuterState::AddPreference(int start_pos, char* pos_str, float weight) { ASSERT_HOST(char_choices_ != NULL); ASSERT_HOST(start_pos + strlen(pos_str) - 1 < word_length_); if (debug_) { tprintf("Copy over %s -> %s @ %d ", pos_str, perm_state_, start_pos); } // copy over preferred position without the terminating null if (!allow_collision_) { int len = strlen(pos_str); for (int i = 0; i < len; ++i) if (position_marked(start_pos + i)) return; } strncpy(&perm_state_[start_pos], pos_str, strlen(pos_str)); adjust_factor_ *= weight; if (debug_) tprintf("==> %s %f\n", perm_state_, adjust_factor_); } // Promote the input blob_choice at specified position with given weight. void PermuterState::AddPreference(int char_pos, BLOB_CHOICE* blob_choice, float weight) { ASSERT_HOST(char_choices_ != NULL); ASSERT_HOST(char_pos < word_length_); // avoid collision (but this doesn't work if the first choice is favored! if (!allow_collision_ && position_marked(char_pos)) return; if (debug_) { tprintf("Set UID %d -> %s @ %d ", blob_choice->unichar_id(), perm_state_, char_pos); } int pos = find_choice_by_uid(char_choices_->get(char_pos), blob_choice->unichar_id()); perm_state_[char_pos] = pos + '0'; adjust_factor_ *= weight; if (debug_) tprintf("==> %s %f\n", perm_state_, adjust_factor_); } // Get the best word permutation so far. Caller should destroy WERD_CHOICE. WERD_CHOICE* PermuterState::GetPermutedWord(float *certainties, float *adjust_factor) { ASSERT_HOST(char_choices_ != NULL); WERD_CHOICE *word_choice = get_choice_from_posstr( unicharset_, *char_choices_, 0, perm_state_, certainties); float rating = word_choice->rating() * adjust_factor_; word_choice->set_rating(rating); *adjust_factor = adjust_factor_; return word_choice; } /********************************************************************** * permute_all * * Permute all the characters together using all of the different types * of permuters/selectors available. Each of the characters must have * a non-NULL choice list. * * Note: order of applying permuters does matter, since the latter * permuter will be recorded if the resulting word ratings are the same. * * Note: the function assumes that best_choice and raw_choice are not NULL. * * Note: Since permuter_all maybe called recursively (through permuter_ * compound_words), there must be a separate instance of permuter_state * for each invocation. **********************************************************************/ WERD_CHOICE *Dict::permute_all(const BLOB_CHOICE_LIST_VECTOR &char_choices, const WERD_CHOICE *best_choice, WERD_CHOICE *raw_choice) { WERD_CHOICE *result1 = NULL; WERD_CHOICE *result2 = NULL; BOOL8 any_alpha; float top_choice_rating_limit = best_choice->rating(); int word_script_id = get_top_word_script(char_choices, getUnicharset()); PermuterState permuter_state; if (getUnicharset().han_sid() != getUnicharset().null_sid() && word_script_id == getUnicharset().han_sid()) { permuter_state.Init(char_choices, getUnicharset(), 1.0f, permute_debug); result1 = get_top_choice_word(char_choices); // Note that we no longer need the returned word from these permuters, // except to delete the memory. The word choice from all permutations // is returned by permuter_state.GetpermutedWord() at the end. if (permute_fixed_length_dawg) { result2 = permute_fixed_length_words(char_choices, &permuter_state); delete result2; } if (permute_chartype_word) { result2 = permute_chartype_words(char_choices, &permuter_state); delete result2; } if (permute_script_word) { result2 = permute_script_words(char_choices, &permuter_state); delete result2; } float certainties[MAX_PERM_LENGTH]; float adjust_factor; result2 = permuter_state.GetPermutedWord(certainties, &adjust_factor); LogNewChoice(adjust_factor, certainties, false, result2); result1 = get_best_delete_other(result1, result2); if (segment_segcost_rating) incorporate_segcost(result1); } else { result1 = permute_top_choice(char_choices, &top_choice_rating_limit, raw_choice, &any_alpha); if (result1 == NULL) return (NULL); if (permute_only_top) return result1; if (permute_chartype_word) { permuter_state.Init(char_choices, getUnicharset(), segment_penalty_garbage, permute_debug); result2 = permute_chartype_words(char_choices, &permuter_state); result1 = get_best_delete_other(result1, result2); } // Permute character fragments if necessary. if (result1 == NULL || result1->fragment_mark()) { result2 = top_fragments_permute_and_select(char_choices, top_choice_rating_limit); result1 = get_best_delete_other(result1, result2); } result2 = dawg_permute_and_select(char_choices, best_choice->rating()); result1 = get_best_delete_other(result1, result2); result2 = permute_compound_words(char_choices, best_choice->rating()); result1 = get_best_delete_other(result1, result2); } return result1; } /** * Incorporate segmentation cost into the word rating. This is done * through a multiplier wordseg_rating_adjust_factor_ which is determined * in bestfirst.cpp during state evaluation. This is not the cleanest * way to do this. It would be better to reorganize the SEARCH_STATE * to keep track of associated states, or do the rating adjustment * outside the permuter in evalaute_state. */ void Dict::incorporate_segcost(WERD_CHOICE *word) { if (!word || wordseg_rating_adjust_factor_ <= 0) return; float old_rating = word->rating(); float new_rating = old_rating * wordseg_rating_adjust_factor_; word->set_rating(new_rating); if (permute_debug) tprintf("Permute segadjust %f * %f --> %f\n", old_rating, wordseg_rating_adjust_factor_, new_rating); } /** * Perform search on fixed-length dictionaries within a word. * This is used for non-space delimited languages like CJK when a "word" * corresponds to a "phrase" consisted of multiple short words. * It iterates over every character position looking for longest matches * against a set of fixed-length dawgs. Each dictionary hit is rewarded * with a rating bonus. * Note: this is very slow as it is performed on every segmentation state. */ WERD_CHOICE* Dict::permute_fixed_length_words( const BLOB_CHOICE_LIST_VECTOR &char_choices, PermuterState *permuter_state) { if (permute_debug) print_char_choices_list("\n\nPermute FixedLength Word", char_choices, getUnicharset(), false); WERD_CHOICE* best_choice = new WERD_CHOICE(&getUnicharset(), char_choices.length()); const int max_dict_len = max_fixed_length_dawgs_wdlen_; const int min_dict_len = 2; char posstr[256]; int match_score = 0; int anchor_pos = 0; while (anchor_pos < char_choices.length()) { // search from longest phrase to shortest, stop when we find a match WERD_CHOICE* part_choice = NULL; int step = max_dict_len; while (step >= min_dict_len) { int end_pos = anchor_pos + step - 1; if (end_pos < char_choices.length()) { part_choice = dawg_permute_and_select(char_choices, 200.0, // rate limit step, anchor_pos); if (part_choice->length() == step) { if (permute_debug) tprintf("match found at pos=%d len=%d\n%s\n", anchor_pos, step, part_choice->unichar_string().string()); break; } delete part_choice; part_choice = NULL; } step--; } if (part_choice && step > 1) { // found lexicon match get_posstr_from_choice(char_choices, part_choice, anchor_pos, posstr); float adjust_factor = pow(0.95, 1.0 + step*2.0/char_choices.length()); if (permuter_state) permuter_state->AddPreference(anchor_pos, posstr, adjust_factor); match_score += step - 1; // single chars don't count if (permute_debug) tprintf("Promote word rating %d-len%d\n%s\n", anchor_pos, step, part_choice->unichar_string().string()); } else { // no lexicon match step = 1; part_choice = get_choice_from_posstr(&getUnicharset(), char_choices, anchor_pos, "0", NULL); if (permute_debug) tprintf("Single char %d %s\n", anchor_pos, part_choice->unichar_string().string()); } if (part_choice && part_choice->length() > 0) (*best_choice) += (*part_choice); if (part_choice) delete part_choice; anchor_pos += step; } if (match_score > 0) { float adjust_factor = pow(0.8, // 1.0/segment_penalty_dict_nonword, match_score * 2.0 / char_choices.length()); float adjusted_score = best_choice->rating() * adjust_factor; if (permute_debug) tprintf("Adjusting score %f @ %d -> %f\n", best_choice->rating(), match_score, adjusted_score); best_choice->set_rating(adjusted_score); } if (permute_debug) tprintf("Found Best CJK word %f: %s\n", best_choice->rating(), best_choice->unichar_string().string()); return best_choice; } /********************************************************************** * Returns the dominant chartype for the word. Only the "main" chartype * of each character is used, and a consistent chartype is defined by * the majority chartype from non-ambiguous character positions. * If pos_chartypes is not NULL, then the "main" chartype at each pos * is also returned. The caller must allocate and deallocate the space. **********************************************************************/ char Dict::top_word_chartype(const BLOB_CHOICE_LIST_VECTOR &char_choices, char* pos_chartypes) { const UNICHARSET &unicharset = getUnicharset(); const int hist_size = 128; // to contain 'A','a','0','x','p' int chprop[hist_size]; int x; for (x = 0; x < hist_size; x++) chprop[x] = 0; for (x = 0; x < char_choices.length(); ++x) { UNICHAR_ID unichar_id = get_top_choice_uid(char_choices.get(x)); char ctype = unicharset.get_chartype(unichar_id); if (pos_chartypes) pos_chartypes[x] = ctype; if (ctype == 0 || ctype == 'p') continue; if (getUnicharAmbigs().OneToOneDefiniteAmbigs(unichar_id) != NULL) continue; chprop[ctype]++; if (x == 0 && ctype == 'A') // first-cap also counts as lower chprop['a']++; } int max_prop = 0; for (x = 1; x < hist_size; x++) if (chprop[x] >= chprop[max_prop]) max_prop = x; return (chprop[max_prop] > 0) ? max_prop : 0; } /********************************************************************** * Promote consistent character type based on neighboring characters. * For each character position, if the top choice property is inconsistent * with that of the word or previous character, then its likely * subsitutions, as defined by DangAmbigs, will be examined and the one * with a matching property will be selected. **********************************************************************/ WERD_CHOICE* Dict::permute_chartype_words( const BLOB_CHOICE_LIST_VECTOR &char_choices, PermuterState *permuter_state) { if (char_choices.length() >= MAX_PERM_LENGTH) return NULL; // Store main character property of top choice at every position char pos_chartypes[MAX_PERM_LENGTH]; char word_type = top_word_chartype(char_choices, pos_chartypes); if (word_type == 0 || word_type == 'p') return NULL; // skip if word type is punctuation or unknown if (permute_debug) { tprintf("\n\nPermuteCharType[%c]\n", word_type); print_char_choices_list("", char_choices, getUnicharset(), true); } WERD_CHOICE *current_word = new WERD_CHOICE(&getUnicharset()); BLOB_CHOICE_IT blob_choice_it; const UNICHARSET& unicharset = getUnicharset(); bool replaced = false; // has any character choice been replaced int prev_unambig_type = 0; // the last chartype of an unambiguous char float certainties[MAX_PERM_LENGTH + 1]; for (int x = 0; x < char_choices.length(); ++x) { BLOB_CHOICE_LIST* pos_choice = char_choices.get(x); UNICHAR_ID unichar_id = get_top_choice_uid(pos_choice); if (unichar_id == 0) { delete current_word; return NULL; } blob_choice_it.set_to_list(pos_choice); BLOB_CHOICE *first_choice = blob_choice_it.data(); ASSERT_HOST(first_choice != NULL); const UnicharIdVector* ambig_uids = getUnicharAmbigs().OneToOneDefiniteAmbigs(unichar_id); bool is_ambiguous = (ambig_uids != NULL); bool is_punct = unicharset.get_ispunctuation(unichar_id); bool is_consistent = is_punct || unicharset.get_chartype(unichar_id) == prev_unambig_type || unicharset.get_chartype(unichar_id) == word_type; bool is_fragment = getUnicharset().get_fragment(unichar_id) != NULL; if (permute_debug) tprintf("char[%d]:%s is_ambig %c is_punct %c is_consistent %c\n", x, unicharset.id_to_unichar(unichar_id), is_ambiguous?'T':'F', is_punct?'T':'F', is_consistent?'T':'F'); if (is_fragment) { // Ignore any fragmented characters by skipping them to next choice // (originally first choice). first_choice = get_nth_choice(pos_choice, 1); ASSERT_HOST(first_choice != NULL); } else if (is_ambiguous && !is_consistent) { // Check every confusable blob choice where the top choice is inconsistent // with the character type of the previous unambiguous character. if (permute_debug) { tprintf("Checking %s r%g PrevCharType %c\n", unicharset.id_to_unichar(unichar_id), first_choice->rating(), prev_unambig_type); print_ratings_list("\t", pos_choice, getUnicharset()); } BLOB_CHOICE* c_it = NULL; if (c_it == NULL) { c_it = find_choice_by_type(pos_choice, word_type, unicharset); } // Prefer a character choice whose type is the same as the previous // unambiguous character and the confusion appears in the ambig list. if (c_it == NULL && prev_unambig_type > 0) { c_it = find_choice_by_type(pos_choice, prev_unambig_type, unicharset); if (c_it && UnicharIdArrayUtils::find_in(*ambig_uids, c_it->unichar_id()) < 0) c_it = NULL; } // Otherwise, perfer a punctuation if (c_it == NULL) { c_it = find_choice_by_type(pos_choice, 'p', unicharset); if (c_it && UnicharIdArrayUtils::find_in(*ambig_uids, c_it->unichar_id()) < 0) c_it = NULL; } // save any preference other than the top choice if (c_it != NULL) { if (permute_debug) { tprintf("Replacing %s r%g ==> %s r%g\n", unicharset.id_to_unichar(unichar_id), first_choice->rating(), unicharset.id_to_unichar(c_it->unichar_id()), c_it->rating()); tprintf("\n\nPermuteCharType[%c]\n", word_type); print_char_choices_list("", char_choices, getUnicharset(), false); } if (permuter_state) permuter_state->AddPreference(x, c_it, segment_reward_chartype); first_choice = c_it; replaced = true; } } else if (!is_ambiguous && !is_punct) { // keep the last unambiguous character type prev_unambig_type = pos_chartypes[x]; } current_word->append_unichar_id(first_choice->unichar_id(), 1, first_choice->rating(), first_choice->certainty()); certainties[x] = first_choice->certainty(); } // All permuter choices should go through adjust_non_word so the choice // rating would be adjusted on the same scale. adjust_non_word(current_word, certainties, permute_debug); if (replaced) { // Apply a reward multiplier on rating if an chartype permutation is made. float rating = current_word->rating(); current_word->set_rating(rating * segment_reward_chartype); if (permute_debug) current_word->print("<== permute_chartype_word **"); } return current_word; } /** * Try flipping characters in a word to get better script consistency. * Similar to how upper/lower case checking is done in top_choice_permuter, * this permuter tries to suggest a more script-consistent choice AND * modifies the rating. So it combines both the case_ok check and * adjust_non_word functionality. However, instead of penalizing an * inconsistent word with a > 1 multiplier, we reward the script-consistent * choice with a < 1 multiplier. */ WERD_CHOICE* Dict::permute_script_words( const BLOB_CHOICE_LIST_VECTOR &char_choices, PermuterState *permuter_state) { if (char_choices.length() >= MAX_WERD_LENGTH) return NULL; int word_sid = get_top_word_script(char_choices, getUnicharset()); if (word_sid == getUnicharset().null_sid()) return NULL; if (permute_debug) { tprintf("\n\nPermuteScript %s\n", getUnicharset().get_script_from_script_id(word_sid)); print_char_choices_list("", char_choices, getUnicharset(), permute_debug > 1); } WERD_CHOICE *current_word = new WERD_CHOICE(&getUnicharset()); BLOB_CHOICE_IT blob_choice_it; bool replaced = false; bool prev_is_consistent = false; float certainties[MAX_PERM_LENGTH + 1]; for (int x = 0; x < char_choices.length(); ++x) { blob_choice_it.set_to_list(char_choices.get(x)); BLOB_CHOICE *first_choice = blob_choice_it.data(); if (!first_choice) { delete current_word; return NULL; } UNICHAR_ID unichar_id = first_choice->unichar_id(); if (unichar_id == 0) { delete current_word; return NULL; } bool sid_consistent = (getUnicharset().get_script(unichar_id) == word_sid); bool this_is_punct = getUnicharset().get_chartype(unichar_id) == 'p'; bool is_fragment = getUnicharset().get_fragment(unichar_id) != NULL; if (is_fragment) { // Ignore any fragmented characters by skipping them to next choice // (originally first choice). first_choice = get_nth_choice(char_choices.get(x), 1); ASSERT_HOST(first_choice != NULL); } else if (!sid_consistent && !this_is_punct && prev_is_consistent) { // If the previous char is CJK, we prefer a cjk over non-cjk char if (permute_debug) { tprintf("Checking %s r%g\n", getUnicharset().id_to_unichar(unichar_id), first_choice->rating()); print_ratings_list("\t", char_choices.get(x), getUnicharset()); } // prefer a script consistent choice BLOB_CHOICE* c_it = find_choice_by_script(char_choices.get(x), word_sid, 0, 0); // otherwise, prefer a punctuation if (c_it == NULL) c_it = find_choice_by_type(char_choices.get(x), 'p', getUnicharset()); if (c_it != NULL) { if (permute_debug) tprintf("Replacing %s r%g ==> %s r%g\n", getUnicharset().id_to_unichar(unichar_id), first_choice->rating(), getUnicharset().id_to_unichar(c_it->unichar_id()), c_it->rating()); if (permuter_state) permuter_state->AddPreference(x, c_it, segment_reward_script); first_choice = c_it; replaced = true; } } current_word->append_unichar_id(first_choice->unichar_id(), 1, first_choice->rating(), first_choice->certainty()); certainties[x] = first_choice->certainty(); prev_is_consistent = sid_consistent; } // All permuter choices should go through adjust_non_word so the choice // rating would be adjusted on the same scale. adjust_non_word(current_word, certainties, permute_debug); if (replaced) { // Apply a reward multiplier on rating if an script permutation is made. float rating = current_word->rating(); current_word->set_rating(rating * segment_reward_script); if (permute_debug) current_word->print("<== permute_script_word **"); } return current_word; } /** * permute_characters * * Permute these characters together according to each of the different * permuters that are enabled. * Returns true if best_choice was updated. */ bool Dict::permute_characters(const BLOB_CHOICE_LIST_VECTOR &char_choices, WERD_CHOICE *best_choice, WERD_CHOICE *raw_choice) { if (permute_debug) { tprintf("\n\n\n##### Permute_Characters #######\n"); print_char_choices_list("\n==> Input CharChoices", char_choices, getUnicharset(), segment_debug > 1); tprintf("\n"); } if (char_choices.length() == 1 && get_top_choice_uid(char_choices.get(0)) == 0) return false; WERD_CHOICE *this_choice = permute_all(char_choices, best_choice, raw_choice); if (this_choice && this_choice->rating() < best_choice->rating()) { *best_choice = *this_choice; if (permute_debug) { best_choice->print("\n**** Populate BestChoice"); cprintf("populate best_choice\n\t%s\n", best_choice->debug_string().string()); } delete this_choice; return true; } delete this_choice; return false; } /** * permute_compound_words * * Return the top choice for each character as the choice for the word. */ WERD_CHOICE *Dict::permute_compound_words( const BLOB_CHOICE_LIST_VECTOR &char_choices, float rating_limit) { BLOB_CHOICE *first_choice; WERD_CHOICE *best_choice = NULL; WERD_CHOICE current_word(&getUnicharset(), MAX_WERD_LENGTH); int first_index = 0; int x; BLOB_CHOICE_IT blob_choice_it; if (char_choices.length() > MAX_WERD_LENGTH) { WERD_CHOICE *bad_word_choice = new WERD_CHOICE(&getUnicharset()); bad_word_choice->make_bad(); return bad_word_choice; } UNICHAR_ID slash = getUnicharset().unichar_to_id("/"); UNICHAR_ID dash = getUnicharset().unichar_to_id("-"); for (x = 0; x < char_choices.length(); ++x) { blob_choice_it.set_to_list(char_choices.get(x)); first_choice = blob_choice_it.data(); if (first_choice->unichar_id() == slash || first_choice->unichar_id() == dash) { if (x > first_index) { if (segment_debug) cprintf ("Hyphenated word found\n"); permute_subword(char_choices, rating_limit, first_index, x - 1, ¤t_word); if (current_word.rating() > rating_limit) break; } // Append hyphen/slash separator to current_word. current_word.append_unichar_id_space_allocated( first_choice->unichar_id(), 1, first_choice->rating(), first_choice->certainty()); first_index = x + 1; // update first_index } } if (first_index > 0 && first_index < x && current_word.rating() <= rating_limit) { permute_subword(char_choices, rating_limit, first_index, x - 1, ¤t_word); best_choice = new WERD_CHOICE(current_word); best_choice->set_permuter(COMPOUND_PERM); } return (best_choice); } /** * permute_subword * * Permute a part of a compound word this subword is bounded by hyphens * and the start and end of the word. Call the standard word permute * function on a set of choices covering only part of the original * word. When it is done reclaim the memory that was used in the * exercise. */ void Dict::permute_subword(const BLOB_CHOICE_LIST_VECTOR &char_choices, float rating_limit, int start, int end, WERD_CHOICE *current_word) { int x; BLOB_CHOICE_LIST_VECTOR subchoices; WERD_CHOICE *best_choice = NULL; WERD_CHOICE raw_choice(&getUnicharset()); raw_choice.make_bad(); DisableChoiceAccum(); for (x = start; x <= end; x++) { if (char_choices.get(x) != NULL) { subchoices += char_choices.get(x); } } if (!subchoices.empty()) { WERD_CHOICE initial_choice(&getUnicharset()); initial_choice.make_bad(); initial_choice.set_rating(rating_limit); best_choice = permute_all(subchoices, &initial_choice, &raw_choice); if (best_choice && best_choice->length() > 0) { *current_word += *best_choice; } else { current_word->set_rating(MAX_FLOAT32); } } else { current_word->set_rating(MAX_FLOAT32); } if (best_choice) delete best_choice; if (segment_debug && current_word->rating() < MAX_FLOAT32) { cprintf ("Subword permuted = %s, %5.2f, %5.2f\n\n", current_word->debug_string().string(), current_word->rating(), current_word->certainty()); } EnableChoiceAccum(); } /** * Return the top choice for each character as the choice for the word. */ WERD_CHOICE *Dict::get_top_choice_word( const BLOB_CHOICE_LIST_VECTOR &char_choices) { WERD_CHOICE *top_word = new WERD_CHOICE(&getUnicharset(), MAX_PERM_LENGTH); float certainties[MAX_PERM_LENGTH]; top_word->set_permuter(TOP_CHOICE_PERM); for (int x = 0; x < char_choices.length(); x++) { BLOB_CHOICE_IT blob_choice_it; blob_choice_it.set_to_list(char_choices.get(x)); BLOB_CHOICE *top_choice = blob_choice_it.data(); top_word->append_unichar_id_space_allocated(top_choice->unichar_id(), 1, top_choice->rating(), top_choice->certainty()); certainties[x] = top_choice->certainty(); } LogNewChoice(1.0, certainties, true, top_word); return top_word; } /** * permute_top_choice * * Return the top choice for each character as the choice for the word. * In addition a choice is created for the best lower and upper case * non-words. In each character position the best lower (or upper) case * character is substituted for the best overall character. */ WERD_CHOICE *Dict::permute_top_choice( const BLOB_CHOICE_LIST_VECTOR &char_choices, float* rating_limit, WERD_CHOICE *raw_choice, BOOL8 *any_alpha) { BLOB_CHOICE *first_choice; const char *first_char; //first choice const char *second_char; //second choice const char *third_char; //third choice char prev_char[UNICHAR_LEN + 1]; //prev in word const char *next_char = ""; //next in word const char *next_next_char = ""; //after next next in word WERD_CHOICE word(&getUnicharset(), MAX_PERM_LENGTH); word.set_permuter(TOP_CHOICE_PERM); WERD_CHOICE capital_word(&getUnicharset(), MAX_PERM_LENGTH); capital_word.set_permuter(UPPER_CASE_PERM); WERD_CHOICE lower_word(&getUnicharset(), MAX_PERM_LENGTH); lower_word.set_permuter(LOWER_CASE_PERM); int x; BOOL8 char_alpha; float first_rating = 0; float certainties[MAX_PERM_LENGTH + 1]; float lower_certainties[MAX_PERM_LENGTH + 1]; float upper_certainties[MAX_PERM_LENGTH + 1]; BLOB_CHOICE_IT blob_choice_it; UNICHAR_ID temp_id; UNICHAR_ID unichar_id; UNICHAR_ID space = getUnicharset().unichar_to_id(" "); register const char* ch; register inT8 lower_done; register inT8 upper_done; prev_char[0] = '\0'; if (any_alpha != NULL) *any_alpha = FALSE; if (char_choices.length() > MAX_PERM_LENGTH) { return (NULL); } for (x = 0; x < char_choices.length(); ++x) { if (x + 1 < char_choices.length()) { unichar_id = get_top_choice_uid(char_choices.get(x+1)); next_char = unichar_id != INVALID_UNICHAR_ID ? getUnicharset().id_to_unichar(unichar_id) : ""; } else { next_char = ""; } if (x + 2 < char_choices.length()) { unichar_id = get_top_choice_uid(char_choices.get(x+2)); next_next_char = unichar_id != INVALID_UNICHAR_ID ? getUnicharset().id_to_unichar(unichar_id) : ""; } else { next_next_char = ""; } blob_choice_it.set_to_list(char_choices.get(x)); ASSERT_HOST(!blob_choice_it.empty()); first_choice = NULL; for (blob_choice_it.mark_cycle_pt(); !blob_choice_it.cycled_list(); blob_choice_it.forward()) { // find the best non-fragment char choice temp_id = blob_choice_it.data()->unichar_id(); if (!(getUnicharset().get_fragment(temp_id))) { first_choice = blob_choice_it.data(); break; } else if (char_choices.length() > 1) { word.set_fragment_mark(true); capital_word.set_fragment_mark(true); lower_word.set_fragment_mark(true); } } if (first_choice == NULL) { cprintf("Permuter found only fragments for" " character at position %d; word=%s\n", x, word.debug_string().string()); } ASSERT_HOST(first_choice != NULL); unichar_id = first_choice->unichar_id() != INVALID_UNICHAR_ID ? first_choice->unichar_id() : space; first_char = getUnicharset().id_to_unichar(unichar_id); first_rating = first_choice->rating(); word.append_unichar_id_space_allocated( unichar_id, 1, first_choice->rating(), first_choice->certainty()); capital_word.append_unichar_id_space_allocated( unichar_id, 1, first_choice->rating(), first_choice->certainty()); lower_word.append_unichar_id_space_allocated( unichar_id, 1, first_choice->rating(), first_choice->certainty()); certainties[x] = first_choice->certainty(); lower_certainties[x] = first_choice->certainty(); upper_certainties[x] = first_choice->certainty(); lower_done = FALSE; upper_done = FALSE; char_alpha = FALSE; second_char = ""; third_char = ""; for (; !blob_choice_it.cycled_list(); blob_choice_it.forward()) { unichar_id = blob_choice_it.data()->unichar_id(); if (getUnicharset().eq(unichar_id, "l") && !blob_choice_it.at_last() && blob_choice_it.data_relative(1)->rating() == first_rating) { temp_id = blob_choice_it.data_relative(1)->unichar_id(); if (getUnicharset().eq(temp_id, "1") || getUnicharset().eq(temp_id, "I")) { second_char = getUnicharset().id_to_unichar(temp_id); blob_choice_it.forward(); if (!blob_choice_it.at_last() && blob_choice_it.data_relative(1)->rating() == first_rating) { temp_id = blob_choice_it.data_relative(1)->unichar_id(); if (getUnicharset().eq(temp_id, "1") || getUnicharset().eq(temp_id, "I")) { third_char = getUnicharset().id_to_unichar(temp_id); blob_choice_it.forward(); } } ch = choose_il1 (first_char, second_char, third_char, prev_char, next_char, next_next_char); unichar_id = (ch != NULL && *ch != '\0') ? getUnicharset().unichar_to_id(ch) : INVALID_UNICHAR_ID; if (strcmp(ch, "l") != 0 && getUnicharset().eq(word.unichar_id(x), "l")) { word.set_unichar_id(unichar_id, x); lower_word.set_unichar_id(unichar_id, x); capital_word.set_unichar_id(unichar_id, x); } } } if (unichar_id != INVALID_UNICHAR_ID) { /* Find lower case */ if (!lower_done && (getUnicharset().get_islower(unichar_id) || (getUnicharset().get_isupper(unichar_id) && x == 0))) { lower_word.set_unichar_id(unichar_id, x); lower_word.set_rating(lower_word.rating() - first_choice->rating() + blob_choice_it.data()->rating()); if (blob_choice_it.data()->certainty() < lower_word.certainty()) { lower_word.set_certainty(blob_choice_it.data()->certainty()); } lower_certainties[x] = blob_choice_it.data()->certainty(); lower_done = TRUE; } /* Find upper case */ if (!upper_done && getUnicharset().get_isupper(unichar_id)) { capital_word.set_unichar_id(unichar_id, x); capital_word.set_rating(capital_word.rating() - first_choice->rating() + blob_choice_it.data()->rating()); if (blob_choice_it.data()->certainty() < capital_word.certainty()) { capital_word.set_certainty(blob_choice_it.data()->certainty()); } upper_certainties[x] = blob_choice_it.data()->certainty(); upper_done = TRUE; } if (!char_alpha) { const CHAR_FRAGMENT *fragment = getUnicharset().get_fragment(unichar_id); temp_id = !fragment ? unichar_id : getUnicharset().unichar_to_id(fragment->get_unichar()); if (getUnicharset().get_isalpha(temp_id)) { char_alpha = TRUE; } } if (lower_done && upper_done) break; } } if (char_alpha && any_alpha != NULL) *any_alpha = TRUE; if (word.rating() > bestrate_pruning_factor * *rating_limit) { if (permute_debug) tprintf("\n***** Aborting high-cost word: %g > limit %g\n", word.rating(), bestrate_pruning_factor * *rating_limit); return (NULL); } *prev_char = '\0'; temp_id = word.unichar_id(word.length()-1); if (temp_id != INVALID_UNICHAR_ID) { strcpy(prev_char, getUnicharset().id_to_unichar(temp_id)); } } if (raw_choice != NULL && word.rating() < raw_choice->rating()) { *raw_choice = word; LogNewChoice(1.0, certainties, true, raw_choice); } float rating = word.rating(); adjust_non_word(&word, certainties, permute_debug); float lower_rating = lower_word.rating(); adjust_non_word(&lower_word, lower_certainties, permute_debug); float upper_rating = capital_word.rating(); adjust_non_word(&capital_word, upper_certainties, permute_debug); WERD_CHOICE *best_choice = &word; *rating_limit = rating; if (lower_word.rating() < best_choice->rating()) { best_choice = &lower_word; *rating_limit = lower_rating; } if (capital_word.rating() < best_choice->rating()) { best_choice = &capital_word; *rating_limit = upper_rating; } return new WERD_CHOICE(*best_choice); } /** * @name choose_il1 * * Choose between the candidate il1 chars. * @param first_char first choice * @param second_char second choice * @param third_char third choice * @param prev_char prev in word * @param next_char next in word * @param next_next_char after next next in word */ const char* Dict::choose_il1(const char *first_char, const char *second_char, const char *third_char, const char *prev_char, const char *next_char, const char *next_next_char) { inT32 type1; //1/I/l type of first choice inT32 type2; //1/I/l type of second choice inT32 type3; //1/I/l type of third choice int first_char_length = strlen(first_char); int prev_char_length = strlen(prev_char); int next_char_length = strlen(next_char); int next_next_char_length = strlen(next_next_char); if (*first_char == 'l' && *second_char != '\0') { if (*second_char == 'I' && (((prev_char_length != 0 && getUnicharset().get_isupper (prev_char, prev_char_length)) && (next_char_length == 0 || !getUnicharset().get_islower (next_char, next_char_length)) && (next_char_length == 0 || !getUnicharset().get_isdigit (next_char, next_char_length))) || ((next_char_length != 0 && getUnicharset().get_isupper (next_char, next_char_length)) && (prev_char_length == 0 || !getUnicharset().get_islower (prev_char, prev_char_length)) && (prev_char_length == 0 || !getUnicharset().get_isdigit (prev_char, prev_char_length))))) first_char = second_char; //override else if (*second_char == '1' || *third_char == '1') { if ((next_char_length != 0 && getUnicharset().get_isdigit (next_char, next_char_length)) || (prev_char_length != 0 && getUnicharset().get_isdigit (prev_char, prev_char_length)) || (*next_char == 'l' && (next_next_char_length != 0 && getUnicharset().get_isdigit (next_next_char, next_next_char_length)))) { first_char = "1"; first_char_length = 1; } else if ((prev_char_length == 0 || !getUnicharset().get_islower (prev_char, prev_char_length)) && ((next_char_length == 0 || !getUnicharset().get_islower (next_char, next_char_length)) || (*next_char == 's' && *next_next_char == 't'))) { if (((*prev_char != '\'' && *prev_char != '`') || *next_char != '\0') && ((*next_char != '\'' && *next_char != '`') || *prev_char != '\0')) { first_char = "1"; first_char_length = 1; } } } if (*first_char == 'l' && *next_char != '\0' && (prev_char_length == 0 || !getUnicharset().get_isalpha (prev_char, prev_char_length))) { type1 = 2; if (*second_char == '1') type2 = 0; else if (*second_char == 'I') type2 = 1; else if (*second_char == 'l') type2 = 2; else type2 = type1; if (*third_char == '1') type3 = 0; else if (*third_char == 'I') type3 = 1; else if (*third_char == 'l') type3 = 2; else type3 = type1; #if 0 if (bigram_counts[*next_char][type2] > bigram_counts[*next_char][type1]) { first_char = second_char; type1 = type2; } if (bigram_counts[*next_char][type3] > bigram_counts[*next_char][type1]) { first_char = third_char; } #endif } } return first_char; } /** * @name fragment_state * * Given the current char choice and information about previously seen * fragments, determines whether adjacent character fragments are * present and whether they can be concatenated. * * The given prev_char_frag_info contains: * - fragment: if not NULL contains information about immediately * preceeding fragmented character choice * - num_fragments: number of fragments that have been used so far * to construct a character * - certainty: certainty of the current choice or minimum * certainty of all fragments concatenated so far * - rating: rating of the current choice or sum of fragment * ratings concatenated so far * * The output char_frag_info is filled in as follows: * - character: is set to be NULL if the choice is a non-matching * or non-ending fragment piece; is set to unichar of the given choice * if it represents a regular character or a matching ending fragment * - fragment,num_fragments,certainty,rating are set as described above * * @returns false if a non-matching fragment is discovered, true otherwise. */ bool Dict::fragment_state_okay(UNICHAR_ID curr_unichar_id, float curr_rating, float curr_certainty, const CHAR_FRAGMENT_INFO *prev_char_frag_info, const char *debug, int word_ending, CHAR_FRAGMENT_INFO *char_frag_info) { const CHAR_FRAGMENT *this_fragment = getUnicharset().get_fragment(curr_unichar_id); const CHAR_FRAGMENT *prev_fragment = prev_char_frag_info != NULL ? prev_char_frag_info->fragment : NULL; // Print debug info for fragments. if (debug && (prev_fragment || this_fragment)) { cprintf("%s check fragments: choice=%s word_ending=%d\n", debug, getUnicharset().debug_str(curr_unichar_id).string(), word_ending); if (prev_fragment) { cprintf("prev_fragment %s\n", prev_fragment->to_string().string()); } if (this_fragment) { cprintf("this_fragment %s\n", this_fragment->to_string().string()); } } char_frag_info->unichar_id = curr_unichar_id; char_frag_info->fragment = this_fragment; char_frag_info->rating = curr_rating; char_frag_info->certainty = curr_certainty; char_frag_info->num_fragments = 1; if (prev_fragment && !this_fragment) { if (debug) tprintf("Skip choice with incomplete fragment\n"); return false; } if (this_fragment) { // We are dealing with a fragment. char_frag_info->unichar_id = INVALID_UNICHAR_ID; if (prev_fragment) { if (!this_fragment->is_continuation_of(prev_fragment)) { if (debug) tprintf("Non-matching fragment piece\n"); return false; } if (this_fragment->is_ending()) { char_frag_info->unichar_id = getUnicharset().unichar_to_id(this_fragment->get_unichar()); char_frag_info->fragment = NULL; if (debug) { tprintf("Built character %s from fragments\n", getUnicharset().debug_str( char_frag_info->unichar_id).string()); } } else { if (debug) tprintf("Record fragment continuation\n"); char_frag_info->fragment = this_fragment; } // Update certainty and rating. char_frag_info->rating = prev_char_frag_info->rating + curr_rating; char_frag_info->num_fragments = prev_char_frag_info->num_fragments + 1; char_frag_info->certainty = MIN(curr_certainty, prev_char_frag_info->certainty); } else { if (this_fragment->is_beginning()) { if (debug) cprintf("Record fragment beginning\n"); } else { if (debug) { tprintf("Non-starting fragment piece with no prev_fragment\n"); } return false; } } } if (word_ending && char_frag_info->fragment) { if (debug) tprintf("Word can not end with a fragment\n"); return false; } return true; } /** * top_fragments_permute_and_select * * Creates a copy of character choices list that contain only fragments * and the best non-fragmented character choice. * Permutes character in this shortened list, builds characters from * fragments if possible and returns a better choice if found. */ WERD_CHOICE *Dict::top_fragments_permute_and_select( const BLOB_CHOICE_LIST_VECTOR &char_choices, float rating_limit) { if (char_choices.length() <= 1 || char_choices.length() > MAX_PERM_LENGTH) { return NULL; } // See it would be possible to benefit from permuting fragments. int x; float min_rating = 0.0; BLOB_CHOICE_IT blob_choice_it; for (x = 0; x < char_choices.length(); ++x) { blob_choice_it.set_to_list(char_choices.get(x)); if (blob_choice_it.data()) { min_rating += blob_choice_it.data()->rating(); } if (min_rating >= rating_limit) { return NULL; } } if (fragments_debug > 1) { tprintf("A choice with fragment beats top choice\n"); tprintf("Running fragment permuter...\n"); } // Construct a modified choices list that contains (for each position): // the best choice, all fragments and at least one choice for // a non-fragmented character. BLOB_CHOICE_LIST_VECTOR frag_char_choices(char_choices.length()); for (x = 0; x < char_choices.length(); ++x) { bool need_nonfrag_char = true; BLOB_CHOICE_LIST *frag_choices = new BLOB_CHOICE_LIST(); BLOB_CHOICE_IT frag_choices_it; frag_choices_it.set_to_list(frag_choices); blob_choice_it.set_to_list(char_choices.get(x)); for (blob_choice_it.mark_cycle_pt(); !blob_choice_it.cycled_list(); blob_choice_it.forward()) { if (getUnicharset().get_fragment(blob_choice_it.data()->unichar_id())) { frag_choices_it.add_after_then_move( new BLOB_CHOICE(*(blob_choice_it.data()))); } else if (need_nonfrag_char) { frag_choices_it.add_after_then_move( new BLOB_CHOICE(*(blob_choice_it.data()))); need_nonfrag_char = false; } } frag_char_choices += frag_choices; } WERD_CHOICE *best_choice = new WERD_CHOICE(&getUnicharset()); best_choice->make_bad(); WERD_CHOICE word(&getUnicharset(), MAX_PERM_LENGTH); word.set_permuter(TOP_CHOICE_PERM); float certainties[MAX_PERM_LENGTH]; this->go_deeper_fxn_ = &tesseract::Dict::go_deeper_top_fragments_fxn; int attempts_left = max_permuter_attempts; permute_choices((fragments_debug > 1) ? "fragments_debug" : NULL, frag_char_choices, 0, NULL, &word, certainties, &rating_limit, best_choice, &attempts_left, NULL); frag_char_choices.delete_data_pointers(); return best_choice; } /** * permute_choices * * Call append_choices() for each BLOB_CHOICE in BLOB_CHOICE_LIST * with the given char_choice_index in char_choices. */ void Dict::permute_choices( const char *debug, const BLOB_CHOICE_LIST_VECTOR &char_choices, int char_choice_index, const CHAR_FRAGMENT_INFO *prev_char_frag_info, WERD_CHOICE *word, float certainties[], float *limit, WERD_CHOICE *best_choice, int *attempts_left, void *more_args) { if (debug) { tprintf("%s permute_choices: char_choice_index=%d" " limit=%g rating=%g, certainty=%g word=%s\n", debug, char_choice_index, *limit, word->rating(), word->certainty(), word->debug_string().string()); } if (char_choice_index < char_choices.length()) { BLOB_CHOICE_IT blob_choice_it; blob_choice_it.set_to_list(char_choices.get(char_choice_index)); for (blob_choice_it.mark_cycle_pt(); !blob_choice_it.cycled_list(); blob_choice_it.forward()) { (*attempts_left)--; append_choices(debug, char_choices, *(blob_choice_it.data()), char_choice_index, prev_char_frag_info, word, certainties, limit, best_choice, attempts_left, more_args); if (*attempts_left <= 0) { if (debug) tprintf("permute_choices(): attempts_left is 0\n"); break; } } } } /** * append_choices * * Checks to see whether or not the next choice is worth appending to * the word being generated. If so then keeps going deeper into the word. * * This function assumes that Dict::go_deeper_fxn_ is set. */ void Dict::append_choices( const char *debug, const BLOB_CHOICE_LIST_VECTOR &char_choices, const BLOB_CHOICE &blob_choice, int char_choice_index, const CHAR_FRAGMENT_INFO *prev_char_frag_info, WERD_CHOICE *word, float certainties[], float *limit, WERD_CHOICE *best_choice, int *attempts_left, void *more_args) { int word_ending = (char_choice_index == char_choices.length() - 1) ? true : false; // Deal with fragments. CHAR_FRAGMENT_INFO char_frag_info; if (!fragment_state_okay(blob_choice.unichar_id(), blob_choice.rating(), blob_choice.certainty(), prev_char_frag_info, debug, word_ending, &char_frag_info)) { return; // blob_choice must be an invalid fragment } // Search the next letter if this character is a fragment. if (char_frag_info.unichar_id == INVALID_UNICHAR_ID) { permute_choices(debug, char_choices, char_choice_index + 1, &char_frag_info, word, certainties, limit, best_choice, attempts_left, more_args); return; } // Add the next unichar. float old_rating = word->rating(); float old_certainty = word->certainty(); uinT8 old_permuter = word->permuter(); certainties[word->length()] = char_frag_info.certainty; word->append_unichar_id_space_allocated( char_frag_info.unichar_id, char_frag_info.num_fragments, char_frag_info.rating, char_frag_info.certainty); // Explore the next unichar. (this->*go_deeper_fxn_)(debug, char_choices, char_choice_index, &char_frag_info, word_ending, word, certainties, limit, best_choice, attempts_left, more_args); // Remove the unichar we added to explore other choices in it's place. word->remove_last_unichar_id(); word->set_rating(old_rating); word->set_certainty(old_certainty); word->set_permuter(old_permuter); } /** * go_deeper_top_fragments_fxn * * While the choice being composed so far could be better * than best_choice keeps exploring char_choices. * If the end of the word is reached and the word is better than * best_choice, copies word to best_choice and logs the new word choice. */ void Dict::go_deeper_top_fragments_fxn( const char *debug, const BLOB_CHOICE_LIST_VECTOR &char_choices, int char_choice_index, const CHAR_FRAGMENT_INFO *prev_char_frag_info, bool word_ending, WERD_CHOICE *word, float certainties[], float *limit, WERD_CHOICE *best_choice, int *attempts_left, void *more_args) { if (word->rating() < *limit) { if (word_ending) { if (fragments_debug > 1) { tprintf("fragments_debug new choice = %s\n", word->debug_string().string()); } *limit = word->rating(); adjust_non_word(word, certainties, permute_debug); update_best_choice(*word, best_choice); } else { // search the next letter permute_choices(debug, char_choices, char_choice_index + 1, prev_char_frag_info, word, certainties, limit, best_choice, attempts_left, more_args); } } else { if (fragments_debug > 1) { tprintf("fragments_debug pruned word (%s, rating=%4.2f, limit=%4.2f)\n", word->debug_string().string(), word->rating(), *limit); } } } } // namespace tesseract