tesseract  4.1.1
ocrclass.h
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1 /**********************************************************************
2  * File: ocrclass.h
3  * Description: Class definitions and constants for the OCR API.
4  * Author: Hewlett-Packard Co
5  *
6  * (C) Copyright 1996, Hewlett-Packard Co.
7  ** Licensed under the Apache License, Version 2.0 (the "License");
8  ** you may not use this file except in compliance with the License.
9  ** You may obtain a copy of the License at
10  ** http://www.apache.org/licenses/LICENSE-2.0
11  ** Unless required by applicable law or agreed to in writing, software
12  ** distributed under the License is distributed on an "AS IS" BASIS,
13  ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  ** See the License for the specific language governing permissions and
15  ** limitations under the License.
16  *
17  **********************************************************************/
18 
19 /**********************************************************************
20  * This file contains typedefs for all the structures used by
21  * the HP OCR interface.
22  * The structures are designed to allow them to be used with any
23  * structure alignment up to 8.
24  **********************************************************************/
25 
26 #ifndef CCUTIL_OCRCLASS_H_
27 #define CCUTIL_OCRCLASS_H_
28 
29 #include <chrono>
30 #include <ctime>
31 #ifdef _WIN32
32 #include <winsock2.h> // for timeval
33 #endif
34 
35 /**********************************************************************
36  * EANYCODE_CHAR
37  * Description of a single character. The character code is defined by
38  * the character set of the current font.
39  * Output text is sent as an array of these structures.
40  * Spaces and line endings in the output are represented in the
41  * structures of the surrounding characters. They are not directly
42  * represented as characters.
43  * The first character in a word has a positive value of blanks.
44  * Missing information should be set to the defaults in the comments.
45  * If word bounds are known, but not character bounds, then the top and
46  * bottom of each character should be those of the word. The left of the
47  * first and right of the last char in each word should be set. All other
48  * lefts and rights should be set to -1.
49  * If set, the values of right and bottom are left+width and top+height.
50  * Most of the members come directly from the parameters to ocr_append_char.
51  * The formatting member uses the enhancement parameter and combines the
52  * line direction stuff into the top 3 bits.
53  * The coding is 0=RL char, 1=LR char, 2=DR NL, 3=UL NL, 4=DR Para,
54  * 5=UL Para, 6=TB char, 7=BT char. API users do not need to know what
55  * the coding is, only that it is backwards compatible with the previous
56  * version.
57  **********************************************************************/
58 
59 typedef struct { /*single character */
60  // It should be noted that the format for char_code for version 2.0 and beyond
61  // is UTF8 which means that ASCII characters will come out as one structure
62  // but other characters will be returned in two or more instances of this
63  // structure with a single byte of the UTF8 code in each, but each will have
64  // the same bounding box. Programs which want to handle languagues with
65  // different characters sets will need to handle extended characters
66  // appropriately, but *all* code needs to be prepared to receive UTF8 coded
67  // characters for characters such as bullet and fancy quotes.
68  uint16_t char_code; /*character itself */
69  int16_t left; /*of char (-1) */
70  int16_t right; /*of char (-1) */
71  int16_t top; /*of char (-1) */
72  int16_t bottom; /*of char (-1) */
73  int16_t font_index; /*what font (0) */
74  uint8_t confidence; /*0=perfect, 100=reject (0/100) */
75  uint8_t point_size; /*of char, 72=i inch, (10) */
76  int8_t blanks; /*no of spaces before this char (1) */
77  uint8_t formatting; /*char formatting (0) */
78 } EANYCODE_CHAR; /*single character */
79 
80 /**********************************************************************
81  * ETEXT_DESC
82  * Description of the output of the OCR engine.
83  * This structure is used as both a progress monitor and the final
84  * output header, since it needs to be a valid progress monitor while
85  * the OCR engine is storing its output to shared memory.
86  * During progress, all the buffer info is -1.
87  * Progress starts at 0 and increases to 100 during OCR. No other constraint.
88  * Additionally the progress callback contains the bounding box of the word that
89  * is currently being processed.
90  * Every progress callback, the OCR engine must set ocr_alive to 1.
91  * The HP side will set ocr_alive to 0. Repeated failure to reset
92  * to 1 indicates that the OCR engine is dead.
93  * If the cancel function is not null then it is called with the number of
94  * user words found. If it returns true then operation is cancelled.
95  **********************************************************************/
96 class ETEXT_DESC;
97 
98 using CANCEL_FUNC = bool (*)(void*, int);
99 using PROGRESS_FUNC = bool (*)(int, int, int, int, int);
100 using PROGRESS_FUNC2 = bool (*)(ETEXT_DESC*, int, int, int, int);
101 
102 class ETEXT_DESC { // output header
103  public:
104  int16_t count{0};
105  int16_t progress{0};
106 
109  int8_t more_to_come{0};
110  volatile int8_t ocr_alive{0};
111  int8_t err_code{0};
112  CANCEL_FUNC cancel{nullptr};
114  nullptr};
116  void* cancel_this{nullptr};
117  struct timeval end_time;
121 
122  ETEXT_DESC() : progress_callback2(&default_progress_func) {
123  auto chrono_end_time = std::chrono::time_point<std::chrono::steady_clock,
124  std::chrono::milliseconds>();
125  timePointToTimeval(chrono_end_time, &end_time);
126  }
127 
128  // Sets the end time to be deadline_msecs milliseconds from now.
129  void set_deadline_msecs(int32_t deadline_msecs) {
130  if (deadline_msecs > 0) {
131  auto chrono_end_time = std::chrono::steady_clock::now() +
132  std::chrono::milliseconds(deadline_msecs);
133  timePointToTimeval(chrono_end_time, &end_time);
134  }
135  }
136 
137  // Returns false if we've not passed the end_time, or have not set a deadline.
138  bool deadline_exceeded() const {
139  if (end_time.tv_sec == 0 && end_time.tv_usec == 0)
140  return false;
141  auto chrono_now = std::chrono::steady_clock::now();
142  struct timeval now;
143  timePointToTimeval(chrono_now, &now);
144  return (now.tv_sec > end_time.tv_sec ||
145  (now.tv_sec == end_time.tv_sec && now.tv_usec > end_time.tv_usec));
146  }
147 
148  private:
149  static void timePointToTimeval(
150  std::chrono::steady_clock::time_point chrono_point, struct timeval* tv) {
151  auto millisecs = std::chrono::duration_cast<std::chrono::milliseconds>(
152  chrono_point.time_since_epoch());
153  tv->tv_sec = millisecs.count() / 1000;
154  tv->tv_usec = (millisecs.count() % 1000) * 1000;
155  }
156 
157  static bool default_progress_func(ETEXT_DESC* ths, int left, int right,
158  int top, int bottom) {
159  if (ths->progress_callback != nullptr) {
160  return (*(ths->progress_callback))(ths->progress, left, right, top,
161  bottom);
162  }
163  return true;
164  }
165 };
166 
167 #endif // CCUTIL_OCRCLASS_H_
int16_t count
Definition: ocrclass.h:104
int16_t font_index
Definition: ocrclass.h:73
uint8_t formatting
Definition: ocrclass.h:77
uint16_t char_code
Definition: ocrclass.h:68
CANCEL_FUNC cancel
for errcode use
Definition: ocrclass.h:112
int16_t progress
chars in this buffer(0)
Definition: ocrclass.h:105
ETEXT_DESC()
character data
Definition: ocrclass.h:122
uint8_t confidence
Definition: ocrclass.h:74
int16_t top
Definition: ocrclass.h:71
int8_t err_code
ocr sets to 1, HP 0
Definition: ocrclass.h:111
volatile int8_t ocr_alive
true if not last
Definition: ocrclass.h:110
bool deadline_exceeded() const
Definition: ocrclass.h:138
int8_t more_to_come
percent complete increasing (0-100)
Definition: ocrclass.h:109
EANYCODE_CHAR text[1]
Definition: ocrclass.h:120
PROGRESS_FUNC progress_callback
returns true to cancel
Definition: ocrclass.h:113
bool(*)(void *, int) CANCEL_FUNC
Definition: ocrclass.h:98
int16_t right
Definition: ocrclass.h:70
struct timeval end_time
this or other data for cancel
Definition: ocrclass.h:117
bool(*)(int, int, int, int, int) PROGRESS_FUNC
Definition: ocrclass.h:99
int8_t blanks
Definition: ocrclass.h:76
bool(*)(ETEXT_DESC *, int, int, int, int) PROGRESS_FUNC2
Definition: ocrclass.h:100
void set_deadline_msecs(int32_t deadline_msecs)
Definition: ocrclass.h:129
PROGRESS_FUNC2 progress_callback2
called whenever progress increases
Definition: ocrclass.h:115
void * cancel_this
monitor-aware progress callback
Definition: ocrclass.h:116
int16_t left
Definition: ocrclass.h:69
int16_t bottom
Definition: ocrclass.h:72
uint8_t point_size
Definition: ocrclass.h:75