tesseract  4.1.1
boxread.h File Reference
#include <cstdio>
#include "strngs.h"

Go to the source code of this file.

Classes

class  GenericVector< T >
 
class  GenericVector< T >
 

Functions

FILE * OpenBoxFile (const STRING &fname)
 
bool ReadAllBoxes (int target_page, bool skip_blanks, const STRING &filename, GenericVector< TBOX > *boxes, GenericVector< STRING > *texts, GenericVector< STRING > *box_texts, GenericVector< int > *pages)
 
bool ReadMemBoxes (int target_page, bool skip_blanks, const char *box_data, bool continue_on_failure, GenericVector< TBOX > *boxes, GenericVector< STRING > *texts, GenericVector< STRING > *box_texts, GenericVector< int > *pages)
 
STRING BoxFileName (const STRING &image_filename)
 
bool ReadNextBox (int *line_number, FILE *box_file, STRING *utf8_str, TBOX *bounding_box)
 
bool ReadNextBox (int target_page, int *line_number, FILE *box_file, STRING *utf8_str, TBOX *bounding_box)
 
bool ParseBoxFileStr (const char *boxfile_str, int *page_number, STRING *utf8_str, TBOX *bounding_box)
 
void MakeBoxFileStr (const char *unichar_str, const TBOX &box, int page_num, STRING *box_str)
 

Variables

const int kBoxReadBufSize = 1024
 

Function Documentation

◆ BoxFileName()

STRING BoxFileName ( const STRING image_filename)

Definition at line 106 of file boxread.cpp.

106  {
107  STRING box_filename = image_filename;
108  const char *lastdot = strrchr(box_filename.string(), '.');
109  if (lastdot != nullptr)
110  box_filename.truncate_at(lastdot - box_filename.string());
111 
112  box_filename += ".box";
113  return box_filename;
114 }

◆ MakeBoxFileStr()

void MakeBoxFileStr ( const char *  unichar_str,
const TBOX box,
int  page_num,
STRING box_str 
)

Definition at line 242 of file boxread.cpp.

243  {
244  *box_str = unichar_str;
245  box_str->add_str_int(" ", box.left());
246  box_str->add_str_int(" ", box.bottom());
247  box_str->add_str_int(" ", box.right());
248  box_str->add_str_int(" ", box.top());
249  box_str->add_str_int(" ", page_num);
250 }

◆ OpenBoxFile()

FILE* OpenBoxFile ( const STRING fname)

Definition at line 36 of file boxread.cpp.

36  {
37  STRING filename = BoxFileName(fname);
38  FILE* box_file = nullptr;
39  if (!(box_file = fopen(filename.string(), "rb"))) {
40  CANTOPENFILE.error("read_next_box", TESSEXIT, "Can't open box file %s",
41  filename.string());
42  }
43  return box_file;
44 }

◆ ParseBoxFileStr()

bool ParseBoxFileStr ( const char *  boxfile_str,
int *  page_number,
STRING utf8_str,
TBOX bounding_box 
)

Definition at line 174 of file boxread.cpp.

175  {
176  *bounding_box = TBOX(); // Initialize it to empty.
177  *utf8_str = "";
178  char uch[kBoxReadBufSize];
179  const char *buffptr = boxfile_str;
180  // Read the unichar without messing up on Tibetan.
181  // According to issue 253 the utf-8 surrogates 85 and A0 are treated
182  // as whitespace by sscanf, so it is more reliable to just find
183  // ascii space and tab.
184  int uch_len = 0;
185  // Skip unicode file designation, if present.
186  const auto *ubuf = reinterpret_cast<const unsigned char*>(buffptr);
187  if (ubuf[0] == 0xef && ubuf[1] == 0xbb && ubuf[2] == 0xbf)
188  buffptr += 3;
189  // Allow a single blank as the UTF-8 string. Check for empty string and
190  // then blindly eat the first character.
191  if (*buffptr == '\0') return false;
192  do {
193  uch[uch_len++] = *buffptr++;
194  } while (*buffptr != '\0' && *buffptr != ' ' && *buffptr != '\t' &&
195  uch_len < kBoxReadBufSize - 1);
196  uch[uch_len] = '\0';
197  if (*buffptr != '\0') ++buffptr;
198  int x_min = INT_MAX;
199  int y_min = INT_MAX;
200  int x_max = INT_MIN;
201  int y_max = INT_MIN;
202  *page_number = 0;
203  std::stringstream stream(buffptr);
204  stream.imbue(std::locale::classic());
205  stream >> x_min;
206  stream >> y_min;
207  stream >> x_max;
208  stream >> y_max;
209  stream >> *page_number;
210  if (x_max < x_min || y_max < y_min) {
211  tprintf("Bad box coordinates in boxfile string! %s\n", ubuf);
212  return false;
213  }
214  // Test for long space-delimited string label.
215  if (strcmp(uch, kMultiBlobLabelCode) == 0 &&
216  (buffptr = strchr(buffptr, '#')) != nullptr) {
217  strncpy(uch, buffptr + 1, kBoxReadBufSize - 1);
218  uch[kBoxReadBufSize - 1] = '\0'; // Prevent buffer overrun.
219  chomp_string(uch);
220  uch_len = strlen(uch);
221  }
222  // Validate UTF8 by making unichars with it.
223  int used = 0;
224  while (used < uch_len) {
225  tesseract::UNICHAR ch(uch + used, uch_len - used);
226  int new_used = ch.utf8_len();
227  if (new_used == 0) {
228  tprintf("Bad UTF-8 str %s starts with 0x%02x at col %d\n",
229  uch + used, uch[used], used + 1);
230  return false;
231  }
232  used += new_used;
233  }
234  *utf8_str = uch;
235  if (x_min > x_max) Swap(&x_min, &x_max);
236  if (y_min > y_max) Swap(&y_min, &y_max);
237  bounding_box->set_to_given_coords(x_min, y_min, x_max, y_max);
238  return true; // Successfully read a box.
239 }

◆ ReadAllBoxes()

bool ReadAllBoxes ( int  target_page,
bool  skip_blanks,
const STRING filename,
GenericVector< TBOX > *  boxes,
GenericVector< STRING > *  texts,
GenericVector< STRING > *  box_texts,
GenericVector< int > *  pages 
)

Definition at line 53 of file boxread.cpp.

57  {
58  GenericVector<char> box_data;
59  if (!tesseract::LoadDataFromFile(BoxFileName(filename).c_str(), &box_data))
60  return false;
61  // Convert the array of bytes to a string, so it can be used by the parser.
62  box_data.push_back('\0');
63  return ReadMemBoxes(target_page, skip_blanks, &box_data[0],
64  /*continue_on_failure*/ true, boxes, texts, box_texts,
65  pages);
66 }

◆ ReadMemBoxes()

bool ReadMemBoxes ( int  target_page,
bool  skip_blanks,
const char *  box_data,
bool  continue_on_failure,
GenericVector< TBOX > *  boxes,
GenericVector< STRING > *  texts,
GenericVector< STRING > *  box_texts,
GenericVector< int > *  pages 
)

Definition at line 69 of file boxread.cpp.

74  {
75  STRING box_str(box_data);
77  box_str.split('\n', &lines);
78  if (lines.empty()) return false;
79  int num_boxes = 0;
80  for (int i = 0; i < lines.size(); ++i) {
81  int page = 0;
82  STRING utf8_str;
83  TBOX box;
84  if (!ParseBoxFileStr(lines[i].string(), &page, &utf8_str, &box)) {
85  if (continue_on_failure)
86  continue;
87  else
88  return false;
89  }
90  if (skip_blanks && (utf8_str == " " || utf8_str == "\t")) continue;
91  if (target_page >= 0 && page != target_page) continue;
92  if (boxes != nullptr) boxes->push_back(box);
93  if (texts != nullptr) texts->push_back(utf8_str);
94  if (box_texts != nullptr) {
95  STRING full_text;
96  MakeBoxFileStr(utf8_str.string(), box, target_page, &full_text);
97  box_texts->push_back(full_text);
98  }
99  if (pages != nullptr) pages->push_back(page);
100  ++num_boxes;
101  }
102  return num_boxes > 0;
103 }

◆ ReadNextBox() [1/2]

bool ReadNextBox ( int *  line_number,
FILE *  box_file,
STRING utf8_str,
TBOX bounding_box 
)

Definition at line 127 of file boxread.cpp.

128  {
129  return ReadNextBox(-1, line_number, box_file, utf8_str, bounding_box);
130 }

◆ ReadNextBox() [2/2]

bool ReadNextBox ( int  target_page,
int *  line_number,
FILE *  box_file,
STRING utf8_str,
TBOX bounding_box 
)

Definition at line 135 of file boxread.cpp.

136  {
137  int page = 0;
138  char buff[kBoxReadBufSize]; // boxfile read buffer
139  char *buffptr = buff;
140 
141  while (fgets(buff, sizeof(buff) - 1, box_file)) {
142  (*line_number)++;
143 
144  buffptr = buff;
145  const auto *ubuf = reinterpret_cast<const unsigned char*>(buffptr);
146  if (ubuf[0] == 0xef && ubuf[1] == 0xbb && ubuf[2] == 0xbf)
147  buffptr += 3; // Skip unicode file designation.
148  // Check for blank lines in box file
149  if (*buffptr == '\n' || *buffptr == '\0') continue;
150  // Skip blank boxes.
151  if (*buffptr == ' ' || *buffptr == '\t') continue;
152  if (*buffptr != '\0') {
153  if (!ParseBoxFileStr(buffptr, &page, utf8_str, bounding_box)) {
154  tprintf("Box file format error on line %i; ignored\n", *line_number);
155  continue;
156  }
157  if (target_page >= 0 && target_page != page)
158  continue; // Not on the appropriate page.
159  return true; // Successfully read a box.
160  }
161  }
162  fclose(box_file);
163  return false; // EOF
164 }

Variable Documentation

◆ kBoxReadBufSize

const int kBoxReadBufSize = 1024

Definition at line 32 of file boxread.h.

TBOX
Definition: rect.h:34
chomp_string
void chomp_string(char *str)
Definition: helpers.h:77
tesseract::LoadDataFromFile
bool LoadDataFromFile(const char *filename, GenericVector< char > *data)
Definition: genericvector.h:375
STRING::string
const char * string() const
Definition: strngs.cpp:194
TESSEXIT
@ TESSEXIT
Definition: errcode.h:44
STRING::add_str_int
void add_str_int(const char *str, int number)
Definition: strngs.cpp:377
TBOX::right
int16_t right() const
Definition: rect.h:79
GenericVector< char >
CANTOPENFILE
constexpr ERRCODE CANTOPENFILE("Can't open file")
kBoxReadBufSize
const int kBoxReadBufSize
Definition: boxread.h:32
ERRCODE::error
void error(const char *caller, TessErrorLogCode action, const char *format,...) const
Definition: errcode.cpp:35
ParseBoxFileStr
bool ParseBoxFileStr(const char *boxfile_str, int *page_number, STRING *utf8_str, TBOX *bounding_box)
Definition: boxread.cpp:174
TBOX::left
int16_t left() const
Definition: rect.h:72
tprintf
DLLSYM void tprintf(const char *format,...)
Definition: tprintf.cpp:35
tesseract::UNICHAR
Definition: unichar.h:57
TBOX::top
int16_t top() const
Definition: rect.h:58
Swap
void Swap(T *p1, T *p2)
Definition: helpers.h:95
TBOX::set_to_given_coords
void set_to_given_coords(int x_min, int y_min, int x_max, int y_max)
Definition: rect.h:271
ReadMemBoxes
bool ReadMemBoxes(int target_page, bool skip_blanks, const char *box_data, bool continue_on_failure, GenericVector< TBOX > *boxes, GenericVector< STRING > *texts, GenericVector< STRING > *box_texts, GenericVector< int > *pages)
Definition: boxread.cpp:69
ReadNextBox
bool ReadNextBox(int *line_number, FILE *box_file, STRING *utf8_str, TBOX *bounding_box)
Definition: boxread.cpp:127
GenericVector::size
int size() const
Definition: genericvector.h:72
STRING::truncate_at
void truncate_at(int32_t index)
Definition: strngs.cpp:265
STRING
Definition: strngs.h:45
MakeBoxFileStr
void MakeBoxFileStr(const char *unichar_str, const TBOX &box, int page_num, STRING *box_str)
Definition: boxread.cpp:242
GenericVector::empty
bool empty() const
Definition: genericvector.h:91
BoxFileName
STRING BoxFileName(const STRING &image_filename)
Definition: boxread.cpp:106
TBOX::bottom
int16_t bottom() const
Definition: rect.h:65
GenericVector::push_back
int push_back(T object)
Definition: genericvector.h:837