tesseract  5.0.0
osdetect.h
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1 // File: osdetect.h
3 // Description: Orientation and script detection.
4 // Author: Samuel Charron
5 // Ranjith Unnikrishnan
6 //
7 // (C) Copyright 2008, 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 //
19 
20 #ifndef TESSERACT_CCMAIN_OSDETECT_H_
21 #define TESSERACT_CCMAIN_OSDETECT_H_
22 
23 #include "export.h" // for TESS_API
24 
25 #include <vector> // for std::vector
26 
27 namespace tesseract {
28 
29 class BLOBNBOX;
30 class BLOBNBOX_CLIST;
31 class BLOB_CHOICE_LIST;
32 class TO_BLOCK_LIST;
33 class UNICHARSET;
34 
35 class Tesseract;
36 
37 // Max number of scripts in ICU + "NULL" + Japanese and Korean + Fraktur
38 const int kMaxNumberOfScripts = 116 + 1 + 2 + 1;
39 
40 struct OSBestResult {
42  : orientation_id(0), script_id(0), sconfidence(0.0), oconfidence(0.0) {}
44  int script_id;
45  float sconfidence;
46  float oconfidence;
47 };
48 
49 struct OSResults {
50  OSResults() : unicharset(nullptr) {
51  for (int i = 0; i < 4; ++i) {
52  for (int j = 0; j < kMaxNumberOfScripts; ++j) {
53  scripts_na[i][j] = 0;
54  }
55  orientations[i] = 0;
56  }
57  }
59  // Set the estimate of the orientation to the given id.
60  void set_best_orientation(int orientation_id);
61  // Update/Compute the best estimate of the script assuming the given
62  // orientation id.
63  void update_best_script(int orientation_id);
64  // Return the index of the script with the highest score for this orientation.
65  TESS_API int get_best_script(int orientation_id) const;
66  // Accumulate scores with given OSResults instance and update the best script.
67  void accumulate(const OSResults &osr);
68 
69  // Print statistics.
70  void print_scores(void) const;
71  void print_scores(int orientation_id) const;
72 
73  // Array holding scores for each orientation id [0,3].
74  // Orientation ids [0..3] map to [0, 270, 180, 90] degree orientations of the
75  // page respectively, where the values refer to the amount of clockwise
76  // rotation to be applied to the page for the text to be upright and readable.
77  float orientations[4];
78  // Script confidence scores for each of 4 possible orientations.
80 
83 };
84 
86 public:
87  OrientationDetector(const std::vector<int> *allowed_scripts,
88  OSResults *results);
89  bool detect_blob(BLOB_CHOICE_LIST *scores);
90  int get_orientation();
91 
92 private:
93  OSResults *osr_;
94  const std::vector<int> *allowed_scripts_;
95 };
96 
98 public:
99  ScriptDetector(const std::vector<int> *allowed_scripts, OSResults *osr,
100  tesseract::Tesseract *tess);
101  void detect_blob(BLOB_CHOICE_LIST *scores);
102  bool must_stop(int orientation) const;
103 
104 private:
105  OSResults *osr_;
106  static const char *korean_script_;
107  static const char *japanese_script_;
108  static const char *fraktur_script_;
109  int korean_id_;
110  int japanese_id_;
111  int katakana_id_;
112  int hiragana_id_;
113  int han_id_;
114  int hangul_id_;
115  int latin_id_;
116  int fraktur_id_;
117  tesseract::Tesseract *tess_;
118  const std::vector<int> *allowed_scripts_;
119 };
120 
121 int orientation_and_script_detection(const char *filename, OSResults *,
123 
124 int os_detect(TO_BLOCK_LIST *port_blocks, OSResults *osr,
125  tesseract::Tesseract *tess);
126 
127 int os_detect_blobs(const std::vector<int> *allowed_scripts,
128  BLOBNBOX_CLIST *blob_list, OSResults *osr,
129  tesseract::Tesseract *tess);
130 
133 
134 // Helper method to convert an orientation index to its value in degrees.
135 // The value represents the amount of clockwise rotation in degrees that must be
136 // applied for the text to be upright (readable).
137 TESS_API int OrientationIdToValue(const int &id);
138 
139 } // namespace tesseract
140 
141 #endif // TESSERACT_CCMAIN_OSDETECT_H_
TESS_API int OrientationIdToValue(const int &id)
Definition: osdetect.cpp:566
int os_detect_blobs(const std::vector< int > *allowed_scripts, BLOBNBOX_CLIST *blob_list, OSResults *osr, tesseract::Tesseract *tess)
Definition: osdetect.cpp:274
const int kMaxNumberOfScripts
Definition: osdetect.h:38
bool os_detect_blob(BLOBNBOX *bbox, OrientationDetector *o, ScriptDetector *s, OSResults *, tesseract::Tesseract *tess)
Definition: osdetect.cpp:323
int orientation_and_script_detection(const char *filename, OSResults *, tesseract::Tesseract *)
Definition: osdetect.cpp:188
int os_detect(TO_BLOCK_LIST *port_blocks, OSResults *osr, tesseract::Tesseract *tess)
Definition: osdetect.cpp:225
OSBestResult best_result
Definition: osdetect.h:82
TESS_API int get_best_script(int orientation_id) const
Definition: osdetect.cpp:113
UNICHARSET * unicharset
Definition: osdetect.h:81
float scripts_na[4][kMaxNumberOfScripts]
Definition: osdetect.h:79
void accumulate(const OSResults &osr)
Definition: osdetect.cpp:145
float orientations[4]
Definition: osdetect.h:77
void print_scores(void) const
Definition: osdetect.cpp:127
void update_best_orientation()
Definition: osdetect.cpp:63
void set_best_orientation(int orientation_id)
Definition: osdetect.cpp:85
void update_best_script(int orientation_id)
Definition: osdetect.cpp:90
bool detect_blob(BLOB_CHOICE_LIST *scores)
Definition: osdetect.cpp:371
OrientationDetector(const std::vector< int > *allowed_scripts, OSResults *results)
Definition: osdetect.cpp:364
void detect_blob(BLOB_CHOICE_LIST *scores)
Definition: osdetect.cpp:461
bool must_stop(int orientation) const
Definition: osdetect.cpp:558
ScriptDetector(const std::vector< int > *allowed_scripts, OSResults *osr, tesseract::Tesseract *tess)
Definition: osdetect.cpp:444
#define TESS_API
Definition: export.h:34