comparison mupdf-source/thirdparty/tesseract/src/ccstruct/blamer.h @ 2:b50eed0cc0ef upstream

ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. The directory name has changed: no version number in the expanded directory now.
author Franz Glasner <fzglas.hg@dom66.de>
date Mon, 15 Sep 2025 11:43:07 +0200
parents
children
comparison
equal deleted inserted replaced
1:1d09e1dec1d9 2:b50eed0cc0ef
1 ///////////////////////////////////////////////////////////////////////
2 // File: blamer.h
3 // Description: Module allowing precise error causes to be allocated.
4 // Author: Rike Antonova
5 // Refactored: Ray Smith
6 //
7 // (C) Copyright 2013, Google Inc.
8 // Licensed under the Apache License, Version 2.0 (the "License");
9 // you may not use this file except in compliance with the License.
10 // You may obtain a copy of the License at
11 // http://www.apache.org/licenses/LICENSE-2.0
12 // Unless required by applicable law or agreed to in writing, software
13 // distributed under the License is distributed on an "AS IS" BASIS,
14 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 // See the License for the specific language governing permissions and
16 // limitations under the License.
17 //
18 ///////////////////////////////////////////////////////////////////////
19
20 #ifndef TESSERACT_CCSTRUCT_BLAMER_H_
21 #define TESSERACT_CCSTRUCT_BLAMER_H_
22
23 #ifdef HAVE_CONFIG_H
24 # include "config_auto.h" // DISABLED_LEGACY_ENGINE
25 #endif
26 #include "boxword.h" // for BoxWord
27 #ifndef DISABLED_LEGACY_ENGINE
28 # include "params_training_featdef.h" // for ParamsTrainingBundle, ParamsTra...
29 #endif // ndef DISABLED_LEGACY_ENGINE
30 #include "ratngs.h" // for BLOB_CHOICE_LIST (ptr only)
31 #include "rect.h" // for TBOX
32 #include "tprintf.h" // for tprintf
33
34 #include <tesseract/unichar.h> // for UNICHAR_ID
35
36 #include <cstdint> // for int16_t
37 #include <cstring> // for memcpy
38 #include <vector> // for std::vector
39
40 namespace tesseract {
41
42 class DENORM;
43 class MATRIX;
44 class UNICHARSET;
45 class WERD_RES;
46
47 struct MATRIX_COORD;
48 struct TWERD;
49
50 class LMPainPoints;
51
52 static const int16_t kBlamerBoxTolerance = 5;
53
54 // Enum for expressing the source of error.
55 // Note: Please update kIncorrectResultReasonNames when modifying this enum.
56 enum IncorrectResultReason {
57 // The text recorded in best choice == truth text
58 IRR_CORRECT,
59 // Either: Top choice is incorrect and is a dictionary word (language model
60 // is unlikely to help correct such errors, so blame the classifier).
61 // Or: the correct unichar was not included in shortlist produced by the
62 // classifier at all.
63 IRR_CLASSIFIER,
64 // Chopper have not found one or more splits that correspond to the correct
65 // character bounding boxes recorded in BlamerBundle::truth_word.
66 IRR_CHOPPER,
67 // Classifier did include correct unichars for each blob in the correct
68 // segmentation, however its rating could have been too bad to allow the
69 // language model to pull out the correct choice. On the other hand the
70 // strength of the language model might have been too weak to favor the
71 // correct answer, this we call this case a classifier-language model
72 // tradeoff error.
73 IRR_CLASS_LM_TRADEOFF,
74 // Page layout failed to produce the correct bounding box. Blame page layout
75 // if the truth was not found for the word, which implies that the bounding
76 // box of the word was incorrect (no truth word had a similar bounding box).
77 IRR_PAGE_LAYOUT,
78 // SegSearch heuristic prevented one or more blobs from the correct
79 // segmentation state to be classified (e.g. the blob was too wide).
80 IRR_SEGSEARCH_HEUR,
81 // The correct segmentaiton state was not explored because of poor SegSearch
82 // pain point prioritization. We blame SegSearch pain point prioritization
83 // if the best rating of a choice constructed from correct segmentation is
84 // better than that of the best choice (i.e. if we got to explore the correct
85 // segmentation state, language model would have picked the correct choice).
86 IRR_SEGSEARCH_PP,
87 // Same as IRR_CLASS_LM_TRADEOFF, but used when we only run chopper on a word,
88 // and thus use the old language model (permuters).
89 // TODO(antonova): integrate the new language mode with chopper
90 IRR_CLASS_OLD_LM_TRADEOFF,
91 // If there is an incorrect adaptive template match with a better score than
92 // a correct one (either pre-trained or adapted), mark this as adaption error.
93 IRR_ADAPTION,
94 // split_and_recog_word() failed to find a suitable split in truth.
95 IRR_NO_TRUTH_SPLIT,
96 // Truth is not available for this word (e.g. when words in corrected content
97 // file are turned into ~~~~ because an appropriate alignment was not found.
98 IRR_NO_TRUTH,
99 // The text recorded in best choice != truth text, but none of the above
100 // reasons are set.
101 IRR_UNKNOWN,
102
103 IRR_NUM_REASONS
104 };
105
106 // Blamer-related information to determine the source of errors.
107 struct BlamerBundle {
108 static const char *IncorrectReasonName(IncorrectResultReason irr);
109 BlamerBundle()
110 : truth_has_char_boxes_(false)
111 , incorrect_result_reason_(IRR_CORRECT)
112 , lattice_data_(nullptr) {
113 ClearResults();
114 }
115 BlamerBundle(const BlamerBundle &other) {
116 this->CopyTruth(other);
117 this->CopyResults(other);
118 }
119 ~BlamerBundle() {
120 delete[] lattice_data_;
121 }
122
123 // Accessors.
124 std::string TruthString() const {
125 std::string truth_str;
126 for (auto &text : truth_text_) {
127 truth_str += text;
128 }
129 return truth_str;
130 }
131 IncorrectResultReason incorrect_result_reason() const {
132 return incorrect_result_reason_;
133 }
134 bool NoTruth() const {
135 return incorrect_result_reason_ == IRR_NO_TRUTH || incorrect_result_reason_ == IRR_PAGE_LAYOUT;
136 }
137 bool HasDebugInfo() const {
138 return debug_.length() > 0 || misadaption_debug_.length() > 0;
139 }
140 const std::string &debug() const {
141 return debug_;
142 }
143 const std::string &misadaption_debug() const {
144 return misadaption_debug_;
145 }
146 void UpdateBestRating(float rating) {
147 if (rating < best_correctly_segmented_rating_) {
148 best_correctly_segmented_rating_ = rating;
149 }
150 }
151 int correct_segmentation_length() const {
152 return correct_segmentation_cols_.size();
153 }
154 // Returns true if the given ratings matrix col,row position is included
155 // in the correct segmentation path at the given index.
156 bool MatrixPositionCorrect(int index, const MATRIX_COORD &coord) {
157 return correct_segmentation_cols_[index] == coord.col &&
158 correct_segmentation_rows_[index] == coord.row;
159 }
160 void set_best_choice_is_dict_and_top_choice(bool value) {
161 best_choice_is_dict_and_top_choice_ = value;
162 }
163 const char *lattice_data() const {
164 return lattice_data_;
165 }
166 int lattice_size() const {
167 return lattice_size_; // size of lattice_data in bytes
168 }
169 void set_lattice_data(const char *data, int size) {
170 lattice_size_ = size;
171 delete[] lattice_data_;
172 lattice_data_ = new char[lattice_size_];
173 memcpy(lattice_data_, data, lattice_size_);
174 }
175 #ifndef DISABLED_LEGACY_ENGINE
176 const tesseract::ParamsTrainingBundle &params_training_bundle() const {
177 return params_training_bundle_;
178 }
179 // Adds a new ParamsTrainingHypothesis to the current hypothesis list.
180 void AddHypothesis(const tesseract::ParamsTrainingHypothesis &hypo) {
181 params_training_bundle_.AddHypothesis(hypo);
182 }
183 #endif // ndef DISABLED_LEGACY_ENGINE
184
185 // Functions to setup the blamer.
186 // Whole word string, whole word bounding box.
187 void SetWordTruth(const UNICHARSET &unicharset, const char *truth_str, const TBOX &word_box);
188 // Single "character" string, "character" bounding box.
189 // May be called multiple times to indicate the characters in a word.
190 void SetSymbolTruth(const UNICHARSET &unicharset, const char *char_str, const TBOX &char_box);
191 // Marks that there is something wrong with the truth text, like it contains
192 // reject characters.
193 void SetRejectedTruth();
194
195 // Returns true if the provided word_choice is correct.
196 bool ChoiceIsCorrect(const WERD_CHOICE *word_choice) const;
197
198 void ClearResults() {
199 norm_truth_word_.DeleteAllBoxes();
200 norm_box_tolerance_ = 0;
201 if (!NoTruth()) {
202 incorrect_result_reason_ = IRR_CORRECT;
203 }
204 debug_ = "";
205 segsearch_is_looking_for_blame_ = false;
206 best_correctly_segmented_rating_ = WERD_CHOICE::kBadRating;
207 correct_segmentation_cols_.clear();
208 correct_segmentation_rows_.clear();
209 best_choice_is_dict_and_top_choice_ = false;
210 delete[] lattice_data_;
211 lattice_data_ = nullptr;
212 lattice_size_ = 0;
213 }
214 void CopyTruth(const BlamerBundle &other) {
215 truth_has_char_boxes_ = other.truth_has_char_boxes_;
216 truth_word_ = other.truth_word_;
217 truth_text_ = other.truth_text_;
218 incorrect_result_reason_ = (other.NoTruth() ? other.incorrect_result_reason_ : IRR_CORRECT);
219 }
220 void CopyResults(const BlamerBundle &other) {
221 norm_truth_word_ = other.norm_truth_word_;
222 norm_box_tolerance_ = other.norm_box_tolerance_;
223 incorrect_result_reason_ = other.incorrect_result_reason_;
224 segsearch_is_looking_for_blame_ = other.segsearch_is_looking_for_blame_;
225 best_correctly_segmented_rating_ = other.best_correctly_segmented_rating_;
226 correct_segmentation_cols_ = other.correct_segmentation_cols_;
227 correct_segmentation_rows_ = other.correct_segmentation_rows_;
228 best_choice_is_dict_and_top_choice_ = other.best_choice_is_dict_and_top_choice_;
229 if (other.lattice_data_ != nullptr) {
230 lattice_data_ = new char[other.lattice_size_];
231 memcpy(lattice_data_, other.lattice_data_, other.lattice_size_);
232 lattice_size_ = other.lattice_size_;
233 } else {
234 lattice_data_ = nullptr;
235 }
236 }
237 const char *IncorrectReason() const;
238
239 // Appends choice and truth details to the given debug string.
240 void FillDebugString(const std::string &msg, const WERD_CHOICE *choice, std::string &debug);
241
242 // Sets up the norm_truth_word from truth_word using the given DENORM.
243 void SetupNormTruthWord(const DENORM &denorm);
244
245 // Splits *this into two pieces in bundle1 and bundle2 (preallocated, empty
246 // bundles) where the right edge/ of the left-hand word is word1_right,
247 // and the left edge of the right-hand word is word2_left.
248 void SplitBundle(int word1_right, int word2_left, bool debug, BlamerBundle *bundle1,
249 BlamerBundle *bundle2) const;
250 // "Joins" the blames from bundle1 and bundle2 into *this.
251 void JoinBlames(const BlamerBundle &bundle1, const BlamerBundle &bundle2, bool debug);
252
253 // If a blob with the same bounding box as one of the truth character
254 // bounding boxes is not classified as the corresponding truth character
255 // blames character classifier for incorrect answer.
256 void BlameClassifier(const UNICHARSET &unicharset, const TBOX &blob_box,
257 const BLOB_CHOICE_LIST &choices, bool debug);
258
259 // Checks whether chops were made at all the character bounding box
260 // boundaries in word->truth_word. If not - blames the chopper for an
261 // incorrect answer.
262 void SetChopperBlame(const WERD_RES *word, bool debug);
263 // Blames the classifier or the language model if, after running only the
264 // chopper, best_choice is incorrect and no blame has been yet set.
265 // Blames the classifier if best_choice is classifier's top choice and is a
266 // dictionary word (i.e. language model could not have helped).
267 // Otherwise, blames the language model (formerly permuter word adjustment).
268 void BlameClassifierOrLangModel(const WERD_RES *word, const UNICHARSET &unicharset,
269 bool valid_permuter, bool debug);
270 // Sets up the correct_segmentation_* to mark the correct bounding boxes.
271 void SetupCorrectSegmentation(const TWERD *word, bool debug);
272
273 // Returns true if a guided segmentation search is needed.
274 bool GuidedSegsearchNeeded(const WERD_CHOICE *best_choice) const;
275 // Setup ready to guide the segmentation search to the correct segmentation.
276 void InitForSegSearch(const WERD_CHOICE *best_choice, MATRIX *ratings, UNICHAR_ID wildcard_id,
277 bool debug, std::string &debug_str, tesseract::LMPainPoints *pain_points,
278 double max_char_wh_ratio, WERD_RES *word_res);
279 // Returns true if the guided segsearch is in progress.
280 bool GuidedSegsearchStillGoing() const;
281 // The segmentation search has ended. Sets the blame appropriately.
282 void FinishSegSearch(const WERD_CHOICE *best_choice, bool debug, std::string &debug_str);
283
284 // If the bundle is null or still does not indicate the correct result,
285 // fix it and use some backup reason for the blame.
286 static void LastChanceBlame(bool debug, WERD_RES *word);
287
288 // Sets the misadaption debug if this word is incorrect, as this word is
289 // being adapted to.
290 void SetMisAdaptionDebug(const WERD_CHOICE *best_choice, bool debug);
291
292 private:
293 // Copy assignment operator (currently unused, therefore private).
294 BlamerBundle &operator=(const BlamerBundle &other) = delete;
295 void SetBlame(IncorrectResultReason irr, const std::string &msg, const WERD_CHOICE *choice,
296 bool debug) {
297 incorrect_result_reason_ = irr;
298 debug_ = IncorrectReason();
299 debug_ += " to blame: ";
300 FillDebugString(msg, choice, debug_);
301 if (debug) {
302 tprintf("SetBlame(): %s", debug_.c_str());
303 }
304 }
305
306 private:
307 // Set to true when bounding boxes for individual unichars are recorded.
308 bool truth_has_char_boxes_;
309 // Variables used by the segmentation search when looking for the blame.
310 // Set to true while segmentation search is continued after the usual
311 // termination condition in order to look for the blame.
312 bool segsearch_is_looking_for_blame_;
313 // Set to true if best choice is a dictionary word and
314 // classifier's top choice.
315 bool best_choice_is_dict_and_top_choice_;
316 // Tolerance for bounding box comparisons in normalized space.
317 int norm_box_tolerance_;
318 // The true_word (in the original image coordinate space) contains ground
319 // truth bounding boxes for this WERD_RES.
320 tesseract::BoxWord truth_word_;
321 // Same as above, but in normalized coordinates
322 // (filled in by WERD_RES::SetupForRecognition()).
323 tesseract::BoxWord norm_truth_word_;
324 // Contains ground truth unichar for each of the bounding boxes in truth_word.
325 std::vector<std::string> truth_text_;
326 // The reason for incorrect OCR result.
327 IncorrectResultReason incorrect_result_reason_;
328 // Debug text associated with the blame.
329 std::string debug_;
330 // Misadaption debug information (filled in if this word was misadapted to).
331 std::string misadaption_debug_;
332 // Vectors populated by SegSearch to indicate column and row indices that
333 // correspond to blobs with correct bounding boxes.
334 std::vector<int> correct_segmentation_cols_;
335 std::vector<int> correct_segmentation_rows_;
336 // Best rating for correctly segmented path
337 // (set and used by SegSearch when looking for blame).
338 float best_correctly_segmented_rating_;
339 int lattice_size_; // size of lattice_data in bytes
340 // Serialized segmentation search lattice.
341 char *lattice_data_;
342 // Information about hypotheses (paths) explored by the segmentation search.
343 #ifndef DISABLED_LEGACY_ENGINE
344 tesseract::ParamsTrainingBundle params_training_bundle_;
345 #endif // ndef DISABLED_LEGACY_ENGINE
346 };
347
348 } // namespace tesseract
349
350 #endif // TESSERACT_CCSTRUCT_BLAMER_H_