tesseract  5.0.0
tesseract::SquishedDawg Class Reference

#include <dawg.h>

Inheritance diagram for tesseract::SquishedDawg:
tesseract::Dawg

Public Member Functions

 SquishedDawg (DawgType type, const std::string &lang, PermuterType perm, int debug_level)
 
 SquishedDawg (const char *filename, DawgType type, const std::string &lang, PermuterType perm, int debug_level)
 
 SquishedDawg (EDGE_ARRAY edges, int num_edges, DawgType type, const std::string &lang, PermuterType perm, int unicharset_size, int debug_level)
 
 ~SquishedDawg () override
 
bool Load (TFile *fp)
 
int NumEdges ()
 
EDGE_REF edge_char_of (NODE_REF node, UNICHAR_ID unichar_id, bool word_end) const override
 Returns the edge that corresponds to the letter out of this node. More...
 
void unichar_ids_of (NODE_REF node, NodeChildVector *vec, bool word_end) const override
 
NODE_REF next_node (EDGE_REF edge) const override
 
bool end_of_word (EDGE_REF edge_ref) const override
 
UNICHAR_ID edge_letter (EDGE_REF edge_ref) const override
 Returns UNICHAR_ID stored in the edge indicated by the given EDGE_REF. More...
 
void print_node (NODE_REF node, int max_num_edges) const override
 
bool write_squished_dawg (TFile *file)
 Writes the squished/reduced Dawg to a file. More...
 
bool write_squished_dawg (const char *filename)
 
- Public Member Functions inherited from tesseract::Dawg
DawgType type () const
 
const std::string & lang () const
 
PermuterType permuter () const
 
virtual ~Dawg ()
 
bool word_in_dawg (const WERD_CHOICE &word) const
 Returns true if the given word is in the Dawg. More...
 
bool prefix_in_dawg (const WERD_CHOICE &prefix, bool requires_complete) const
 
int check_for_words (const char *filename, const UNICHARSET &unicharset, bool enable_wildcard) const
 
void iterate_words (const UNICHARSET &unicharset, std::function< void(const WERD_CHOICE *)> cb) const
 
void iterate_words (const UNICHARSET &unicharset, const std::function< void(const char *)> &cb) const
 
virtual void unichar_id_to_patterns (UNICHAR_ID unichar_id, const UNICHARSET &unicharset, std::vector< UNICHAR_ID > *vec) const
 
virtual EDGE_REF pattern_loop_edge (EDGE_REF edge_ref, UNICHAR_ID unichar_id, bool word_end) const
 

Additional Inherited Members

- Static Public Attributes inherited from tesseract::Dawg
static const int16_t kDawgMagicNumber = 42
 Magic number to determine endianness when reading the Dawg from file. More...
 
static const UNICHAR_ID kPatternUnicharID = 0
 
- Protected Member Functions inherited from tesseract::Dawg
 Dawg (DawgType type, const std::string &lang, PermuterType perm, int debug_level)
 
NODE_REF next_node_from_edge_rec (const EDGE_RECORD &edge_rec) const
 Returns the next node visited by following this edge. More...
 
bool marker_flag_from_edge_rec (const EDGE_RECORD &edge_rec) const
 Returns the marker flag of this edge. More...
 
int direction_from_edge_rec (const EDGE_RECORD &edge_rec) const
 Returns the direction flag of this edge. More...
 
bool end_of_word_from_edge_rec (const EDGE_RECORD &edge_rec) const
 Returns true if this edge marks the end of a word. More...
 
UNICHAR_ID unichar_id_from_edge_rec (const EDGE_RECORD &edge_rec) const
 Returns UNICHAR_ID recorded in this edge. More...
 
void set_next_node_in_edge_rec (EDGE_RECORD *edge_rec, EDGE_REF value)
 Sets the next node link for this edge in the Dawg. More...
 
void set_marker_flag_in_edge_rec (EDGE_RECORD *edge_rec)
 Sets this edge record to be the last one in a sequence of edges. More...
 
int given_greater_than_edge_rec (NODE_REF next_node, bool word_end, UNICHAR_ID unichar_id, const EDGE_RECORD &edge_rec) const
 
bool edge_rec_match (NODE_REF next_node, bool word_end, UNICHAR_ID unichar_id, NODE_REF other_next_node, bool other_word_end, UNICHAR_ID other_unichar_id) const
 
void init (int unicharset_size)
 
bool match_words (WERD_CHOICE *word, uint32_t index, NODE_REF node, UNICHAR_ID wildcard) const
 
void iterate_words_rec (const WERD_CHOICE &word_so_far, NODE_REF to_explore, const std::function< void(const WERD_CHOICE *)> &cb) const
 
- Protected Attributes inherited from tesseract::Dawg
std::string lang_
 
DawgType type_
 
PermuterType perm_
 Permuter code that should be used if the word is found in this Dawg. More...
 
uint64_t next_node_mask_ = 0
 
uint64_t flags_mask_ = 0
 
uint64_t letter_mask_ = 0
 
int unicharset_size_
 
int flag_start_bit_ = 0
 
int next_node_start_bit_ = 0
 
int debug_level_
 

Detailed Description

Concrete class that can operate on a compacted (squished) Dawg (read, search and write to file). This class is read-only in the sense that new words can not be added to an instance of SquishedDawg. The underlying representation of the nodes and edges in SquishedDawg is stored as a contiguous EDGE_ARRAY (read from file or given as an argument to the constructor).

Definition at line 408 of file dawg.h.

Constructor & Destructor Documentation

◆ SquishedDawg() [1/3]

tesseract::SquishedDawg::SquishedDawg ( DawgType  type,
const std::string &  lang,
PermuterType  perm,
int  debug_level 
)
inline

Definition at line 410 of file dawg.h.

412  : Dawg(type, lang, perm, debug_level) {}
const std::string & lang() const
Definition: dawg.h:122
Dawg(DawgType type, const std::string &lang, PermuterType perm, int debug_level)
Definition: dawg.h:201
DawgType type() const
Definition: dawg.h:119

◆ SquishedDawg() [2/3]

tesseract::SquishedDawg::SquishedDawg ( const char *  filename,
DawgType  type,
const std::string &  lang,
PermuterType  perm,
int  debug_level 
)
inline

Definition at line 413 of file dawg.h.

415  : Dawg(type, lang, perm, debug_level) {
416  TFile file;
417  ASSERT_HOST(file.Open(filename, nullptr));
418  ASSERT_HOST(read_squished_dawg(&file));
419  num_forward_edges_in_node0 = num_forward_edges(0);
420  }
#define ASSERT_HOST(x)
Definition: errcode.h:59
static FILE * Open(const std::string &filename, const std::string &mode)
Definition: fileio.cpp:41

◆ SquishedDawg() [3/3]

tesseract::SquishedDawg::SquishedDawg ( EDGE_ARRAY  edges,
int  num_edges,
DawgType  type,
const std::string &  lang,
PermuterType  perm,
int  unicharset_size,
int  debug_level 
)
inline

Definition at line 421 of file dawg.h.

424  : Dawg(type, lang, perm, debug_level),
425  edges_(edges),
426  num_edges_(num_edges) {
427  init(unicharset_size);
428  num_forward_edges_in_node0 = num_forward_edges(0);
429  if (debug_level > 3) {
430  print_all("SquishedDawg:");
431  }
432  }
void init(int unicharset_size)
Definition: dawg.cpp:178

◆ ~SquishedDawg()

tesseract::SquishedDawg::~SquishedDawg ( )
override

Definition at line 194 of file dawg.cpp.

194  {
195  delete[] edges_;
196 }

Member Function Documentation

◆ edge_char_of()

EDGE_REF tesseract::SquishedDawg::edge_char_of ( NODE_REF  node,
UNICHAR_ID  unichar_id,
bool  word_end 
) const
overridevirtual

Returns the edge that corresponds to the letter out of this node.

Implements tesseract::Dawg.

Definition at line 198 of file dawg.cpp.

199  {
200  EDGE_REF edge = node;
201  if (node == 0) { // binary search
202  EDGE_REF start = 0;
203  EDGE_REF end = num_forward_edges_in_node0 - 1;
204  int compare;
205  while (start <= end) {
206  edge = (start + end) >> 1; // (start + end) / 2
207  compare = given_greater_than_edge_rec(NO_EDGE, word_end, unichar_id,
208  edges_[edge]);
209  if (compare == 0) { // given == vec[k]
210  return edge;
211  } else if (compare == 1) { // given > vec[k]
212  start = edge + 1;
213  } else { // given < vec[k]
214  end = edge - 1;
215  }
216  }
217  } else { // linear search
218  if (edge != NO_EDGE && edge_occupied(edge)) {
219  do {
220  if ((unichar_id_from_edge_rec(edges_[edge]) == unichar_id) &&
221  (!word_end || end_of_word_from_edge_rec(edges_[edge]))) {
222  return (edge);
223  }
224  } while (!last_edge(edge++));
225  }
226  }
227  return (NO_EDGE); // not found
228 }
int64_t EDGE_REF
Definition: dawg.h:49
int given_greater_than_edge_rec(NODE_REF next_node, bool word_end, UNICHAR_ID unichar_id, const EDGE_RECORD &edge_rec) const
Definition: dawg.h:247
bool end_of_word_from_edge_rec(const EDGE_RECORD &edge_rec) const
Returns true if this edge marks the end of a word.
Definition: dawg.h:223
UNICHAR_ID unichar_id_from_edge_rec(const EDGE_RECORD &edge_rec) const
Returns UNICHAR_ID recorded in this edge.
Definition: dawg.h:227

◆ edge_letter()

UNICHAR_ID tesseract::SquishedDawg::edge_letter ( EDGE_REF  edge_ref) const
inlineoverridevirtual

Returns UNICHAR_ID stored in the edge indicated by the given EDGE_REF.

Implements tesseract::Dawg.

Definition at line 481 of file dawg.h.

481  {
482  return unichar_id_from_edge_rec((edges_[edge_ref]));
483  }

◆ end_of_word()

bool tesseract::SquishedDawg::end_of_word ( EDGE_REF  edge_ref) const
inlineoverridevirtual

Returns true if the edge indicated by the given EDGE_REF marks the end of a word.

Implements tesseract::Dawg.

Definition at line 476 of file dawg.h.

476  {
477  return end_of_word_from_edge_rec((edges_[edge_ref]));
478  }

◆ Load()

bool tesseract::SquishedDawg::Load ( TFile fp)
inline

Definition at line 436 of file dawg.h.

436  {
437  if (!read_squished_dawg(fp)) {
438  return false;
439  }
440  num_forward_edges_in_node0 = num_forward_edges(0);
441  return true;
442  }

◆ next_node()

NODE_REF tesseract::SquishedDawg::next_node ( EDGE_REF  edge) const
inlineoverridevirtual

Returns the next node visited by following the edge indicated by the given EDGE_REF.

Implements tesseract::Dawg.

Definition at line 470 of file dawg.h.

470  {
471  return next_node_from_edge_rec((edges_[edge]));
472  }
NODE_REF next_node_from_edge_rec(const EDGE_RECORD &edge_rec) const
Returns the next node visited by following this edge.
Definition: dawg.h:210

◆ NumEdges()

int tesseract::SquishedDawg::NumEdges ( )
inline

Definition at line 444 of file dawg.h.

444  {
445  return num_edges_;
446  }

◆ print_node()

void tesseract::SquishedDawg::print_node ( NODE_REF  node,
int  max_num_edges 
) const
overridevirtual

Prints the contents of the node indicated by the given NODE_REF. At most max_num_edges will be printed.

Implements tesseract::Dawg.

Definition at line 243 of file dawg.cpp.

243  {
244  if (node == NO_EDGE) {
245  return; // nothing to print
246  }
247 
248  EDGE_REF edge = node;
249  const char *forward_string = "FORWARD";
250  const char *backward_string = " ";
251 
252  const char *last_string = "LAST";
253  const char *not_last_string = " ";
254 
255  const char *eow_string = "EOW";
256  const char *not_eow_string = " ";
257 
258  const char *direction;
259  const char *is_last;
260  const char *eow;
261 
262  UNICHAR_ID unichar_id;
263 
264  if (edge_occupied(edge)) {
265  do {
266  direction = forward_edge(edge) ? forward_string : backward_string;
267  is_last = last_edge(edge) ? last_string : not_last_string;
268  eow = end_of_word(edge) ? eow_string : not_eow_string;
269 
270  unichar_id = edge_letter(edge);
271  tprintf(REFFORMAT " : next = " REFFORMAT ", unichar_id = %d, %s %s %s\n",
272  edge, next_node(edge), unichar_id, direction, is_last, eow);
273 
274  if (edge - node > max_num_edges) {
275  return;
276  }
277  } while (!last_edge(edge++));
278 
279  if (edge < num_edges_ && edge_occupied(edge) && backward_edge(edge)) {
280  do {
281  direction = forward_edge(edge) ? forward_string : backward_string;
282  is_last = last_edge(edge) ? last_string : not_last_string;
283  eow = end_of_word(edge) ? eow_string : not_eow_string;
284 
285  unichar_id = edge_letter(edge);
286  tprintf(REFFORMAT " : next = " REFFORMAT
287  ", unichar_id = %d, %s %s %s\n",
288  edge, next_node(edge), unichar_id, direction, is_last, eow);
289 
290  if (edge - node > MAX_NODE_EDGES_DISPLAY) {
291  return;
292  }
293  } while (!last_edge(edge++));
294  }
295  } else {
296  tprintf(REFFORMAT " : no edges in this node\n", node);
297  }
298  tprintf("\n");
299 }
#define MAX_NODE_EDGES_DISPLAY
Definition: dawg.h:79
#define REFFORMAT
Definition: dawg.h:85
void tprintf(const char *format,...)
Definition: tprintf.cpp:41
int UNICHAR_ID
Definition: unichar.h:36
bool end_of_word(EDGE_REF edge_ref) const override
Definition: dawg.h:476
UNICHAR_ID edge_letter(EDGE_REF edge_ref) const override
Returns UNICHAR_ID stored in the edge indicated by the given EDGE_REF.
Definition: dawg.h:481
NODE_REF next_node(EDGE_REF edge) const override
Definition: dawg.h:470

◆ unichar_ids_of()

void tesseract::SquishedDawg::unichar_ids_of ( NODE_REF  node,
NodeChildVector vec,
bool  word_end 
) const
inlineoverridevirtual

Fills the given NodeChildVector with all the unichar ids (and the corresponding EDGE_REFs) for which there is an edge out of this node.

Implements tesseract::Dawg.

Definition at line 454 of file dawg.h.

455  {
456  EDGE_REF edge = node;
457  if (!edge_occupied(edge) || edge == NO_EDGE) {
458  return;
459  }
460  assert(forward_edge(edge)); // we don't expect any backward edges to
461  do { // be present when this function is called
462  if (!word_end || end_of_word_from_edge_rec(edges_[edge])) {
463  vec->push_back(NodeChild(unichar_id_from_edge_rec(edges_[edge]), edge));
464  }
465  } while (!last_edge(edge++));
466  }

◆ write_squished_dawg() [1/2]

bool tesseract::SquishedDawg::write_squished_dawg ( const char *  filename)
inline

Opens the file with the given filename and writes the squished/reduced Dawg to the file.

Definition at line 494 of file dawg.h.

494  {
495  TFile file;
496  file.OpenWrite(nullptr);
497  if (!this->write_squished_dawg(&file)) {
498  tprintf("Error serializing %s\n", filename);
499  return false;
500  }
501  if (!file.CloseWrite(filename, nullptr)) {
502  tprintf("Error writing file %s\n", filename);
503  return false;
504  }
505  return true;
506  }
bool write_squished_dawg(TFile *file)
Writes the squished/reduced Dawg to a file.
Definition: dawg.cpp:391

◆ write_squished_dawg() [2/2]

bool tesseract::SquishedDawg::write_squished_dawg ( TFile file)

Writes the squished/reduced Dawg to a file.

Definition at line 391 of file dawg.cpp.

391  {
392  EDGE_REF edge;
393  int32_t num_edges;
394  int32_t node_count = 0;
395  EDGE_REF old_index;
396  EDGE_RECORD temp_record;
397 
398  if (debug_level_) {
399  tprintf("write_squished_dawg\n");
400  }
401 
402  std::unique_ptr<EDGE_REF[]> node_map(build_node_map(&node_count));
403 
404  // Write the magic number to help detecting a change in endianness.
405  int16_t magic = kDawgMagicNumber;
406  if (!file->Serialize(&magic)) {
407  return false;
408  }
409  if (!file->Serialize(&unicharset_size_)) {
410  return false;
411  }
412 
413  // Count the number of edges in this Dawg.
414  num_edges = 0;
415  for (edge = 0; edge < num_edges_; edge++) {
416  if (forward_edge(edge)) {
417  num_edges++;
418  }
419  }
420 
421  // Write edge count to file.
422  if (!file->Serialize(&num_edges)) {
423  return false;
424  }
425 
426  if (debug_level_) {
427  tprintf("%d nodes in DAWG\n", node_count);
428  tprintf("%d edges in DAWG\n", num_edges);
429  }
430 
431  for (edge = 0; edge < num_edges_; edge++) {
432  if (forward_edge(edge)) { // write forward edges
433  do {
434  old_index = next_node_from_edge_rec(edges_[edge]);
435  set_next_node(edge, node_map[old_index]);
436  temp_record = edges_[edge];
437  if (!file->Serialize(&temp_record)) {
438  return false;
439  }
440  set_next_node(edge, old_index);
441  } while (!last_edge(edge++));
442 
443  if (edge >= num_edges_) {
444  break;
445  }
446  if (backward_edge(edge)) { // skip back links
447  while (!last_edge(edge++)) {
448  ;
449  }
450  }
451 
452  edge--;
453  }
454  }
455  return true;
456 }
uint64_t EDGE_RECORD
Definition: dawg.h:47
int unicharset_size_
Definition: dawg.h:313
int debug_level_
Definition: dawg.h:317
static const int16_t kDawgMagicNumber
Magic number to determine endianness when reading the Dawg from file.
Definition: dawg.h:113

The documentation for this class was generated from the following files: