mirror/tesseract
1
0
Fork 0
mirror of https://github.com/tesseract-ocr/tesseract.git synced 2024-11-27 12:49:35 +08:00
Code Issues Actions 10 Packages Projects Releases Wiki Activity

doxygenify

Browse Source
This commit is contained in:
Jim O'Regan 2015-05-14 14:53:00 +01:00
parent 020eb00912
commit 524666d9fa
1 changed files with 74 additions and 71 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

145
wordrec/lm_state.h
View File

@ -33,28 +33,31 @@
namespace tesseract {
// Used for expressing various language model flags.
/// Used for expressing various language model flags.
typedef unsigned char LanguageModelFlagsType;
// The following structs are used for storing the state of the language model
// in the segmentation search graph. In this graph the nodes are BLOB_CHOICEs
// and the links are the relationships between the underlying blobs (see
// segsearch.h for a more detailed description).
// Each of the BLOB_CHOICEs contains LanguageModelState struct, which has
// a list of N best paths (list of ViterbiStateEntry) explored by the Viterbi
// search leading up to and including this BLOB_CHOICE.
// Each ViterbiStateEntry contains information from various components of the
// language model: dawgs in which the path is found, character ngram model
// probability of the path, script/chartype/font consistency info, state for
// language-specific heuristics (e.g. hyphenated and compound words, lower/upper
// case preferences, etc).
// Each ViterbiStateEntry also contains the parent pointer, so that the path
// that it represents (WERD_CHOICE) can be constructed by following these
// parent pointers.
/// The following structs are used for storing the state of the language model
/// in the segmentation search graph. In this graph the nodes are BLOB_CHOICEs
/// and the links are the relationships between the underlying blobs (see
/// segsearch.h for a more detailed description).
///
/// Each of the BLOB_CHOICEs contains LanguageModelState struct, which has
/// a list of N best paths (list of ViterbiStateEntry) explored by the Viterbi
/// search leading up to and including this BLOB_CHOICE.
///
/// Each ViterbiStateEntry contains information from various components of the
/// language model: dawgs in which the path is found, character ngram model
/// probability of the path, script/chartype/font consistency info, state for
/// language-specific heuristics (e.g. hyphenated and compound words, lower/upper
/// case preferences, etc).
///
/// Each ViterbiStateEntry also contains the parent pointer, so that the path
/// that it represents (WERD_CHOICE) can be constructed by following these
/// parent pointers.
// Struct for storing additional information used by Dawg language model
// component. It stores the set of active dawgs in which the sequence of
// letters on a path can be found.
/// Struct for storing additional information used by Dawg language model
/// component. It stores the set of active dawgs in which the sequence of
/// letters on a path can be found.
struct LanguageModelDawgInfo {
LanguageModelDawgInfo(DawgPositionVector *a, PermuterType pt) : permuter(pt) {
active_dawgs = new DawgPositionVector(*a);
@ -66,29 +69,29 @@ struct LanguageModelDawgInfo {
PermuterType permuter;
};
// Struct for storing additional information used by Ngram language model
// component.
/// Struct for storing additional information used by Ngram language model
/// component.
struct LanguageModelNgramInfo {
LanguageModelNgramInfo(const char *c, int l, bool p, float nc, float ncc)
: context(c), context_unichar_step_len(l), pruned(p), ngram_cost(nc),
ngram_and_classifier_cost(ncc) {}
STRING context; // context string
// Length of the context measured by advancing using UNICHAR::utf8_step()
// (should be at most the order of the character ngram model used).
STRING context; //< context string
/// Length of the context measured by advancing using UNICHAR::utf8_step()
/// (should be at most the order of the character ngram model used).
int context_unichar_step_len;
// The paths with pruned set are pruned out from the perspective of the
// character ngram model. They are explored further because they represent
// a dictionary match or a top choice. Thus ngram_info is still computed
// for them in order to calculate the combined cost.
/// The paths with pruned set are pruned out from the perspective of the
/// character ngram model. They are explored further because they represent
/// a dictionary match or a top choice. Thus ngram_info is still computed
/// for them in order to calculate the combined cost.
bool pruned;
// -ln(P_ngram_model(path))
/// -ln(P_ngram_model(path))
float ngram_cost;
// -[ ln(P_classifier(path)) + scale_factor * ln(P_ngram_model(path)) ]
/// -[ ln(P_classifier(path)) + scale_factor * ln(P_ngram_model(path)) ]
float ngram_and_classifier_cost;
};
// Struct for storing the information about a path in the segmentation graph
// explored by Viterbi search.
/// Struct for storing the information about a path in the segmentation graph
/// explored by Viterbi search.
struct ViterbiStateEntry : public ELIST_LINK {
ViterbiStateEntry(ViterbiStateEntry *pe,
BLOB_CHOICE *b, float c, float ol,
@ -122,8 +125,8 @@ struct ViterbiStateEntry : public ELIST_LINK {
delete ngram_info;
delete debug_str;
}
// Comparator function for sorting ViterbiStateEntry_LISTs in
// non-increasing order of costs.
/// Comparator function for sorting ViterbiStateEntry_LISTs in
/// non-increasing order of costs.
static int Compare(const void *e1, const void *e2) {
const ViterbiStateEntry *ve1 =
*reinterpret_cast<const ViterbiStateEntry * const *>(e1);
@ -137,8 +140,8 @@ struct ViterbiStateEntry : public ELIST_LINK {
}
return consistency_info.Consistent();
}
// Returns true if this VSE has an alphanumeric character as its classifier
// result.
/// Returns true if this VSE has an alphanumeric character as its classifier
/// result.
bool HasAlnumChoice(const UNICHARSET& unicharset) {
if (curr_b == NULL) return false;
UNICHAR_ID unichar_id = curr_b->unichar_id();
@ -149,48 +152,48 @@ struct ViterbiStateEntry : public ELIST_LINK {
}
void Print(const char *msg) const;
// The cost is an adjusted ratings sum, that is adjusted by all the language
// model components that use Viterbi search.
/// The cost is an adjusted ratings sum, that is adjusted by all the language
/// model components that use Viterbi search.
float cost;
// Pointers to BLOB_CHOICE and parent ViterbiStateEntry (not owned by this).
/// Pointers to BLOB_CHOICE and parent ViterbiStateEntry (not owned by this).
BLOB_CHOICE *curr_b;
ViterbiStateEntry *parent_vse;
// Pointer to a case-competing ViterbiStateEntry in the same list that
// represents a path ending in the same letter of the opposite case.
/// Pointer to a case-competing ViterbiStateEntry in the same list that
/// represents a path ending in the same letter of the opposite case.
ViterbiStateEntry *competing_vse;
// Various information about the characters on the path represented
// by this ViterbiStateEntry.
float ratings_sum; // sum of ratings of character on the path
float min_certainty; // minimum certainty on the path
int adapted; // number of BLOB_CHOICES from adapted templates
int length; // number of characters on the path
float outline_length; // length of the outline so far
LMConsistencyInfo consistency_info; // path consistency info
AssociateStats associate_stats; // character widths/gaps/seams
/// Various information about the characters on the path represented
/// by this ViterbiStateEntry.
float ratings_sum; //< sum of ratings of character on the path
float min_certainty; //< minimum certainty on the path
int adapted; //< number of BLOB_CHOICES from adapted templates
int length; //< number of characters on the path
float outline_length; //< length of the outline so far
LMConsistencyInfo consistency_info; //< path consistency info
AssociateStats associate_stats; //< character widths/gaps/seams
// Flags for marking the entry as a top choice path with
// the smallest rating or lower/upper case letters).
/// Flags for marking the entry as a top choice path with
/// the smallest rating or lower/upper case letters).
LanguageModelFlagsType top_choice_flags;
// Extra information maintained by Dawg laguage model component
// (owned by ViterbiStateEntry).
/// Extra information maintained by Dawg laguage model component
/// (owned by ViterbiStateEntry).
LanguageModelDawgInfo *dawg_info;
// Extra information maintained by Ngram laguage model component
// (owned by ViterbiStateEntry).
/// Extra information maintained by Ngram laguage model component
/// (owned by ViterbiStateEntry).
LanguageModelNgramInfo *ngram_info;
bool updated; // set to true if the entry has just been created/updated
// UTF8 string representing the path corresponding to this vse.
// Populated only in when language_model_debug_level > 0.
bool updated; //< set to true if the entry has just been created/updated
/// UTF8 string representing the path corresponding to this vse.
/// Populated only in when language_model_debug_level > 0.
STRING *debug_str;
};
ELISTIZEH(ViterbiStateEntry);
// Struct to store information maintained by various language model components.
/// Struct to store information maintained by various language model components.
struct LanguageModelState {
LanguageModelState() :
viterbi_state_entries_prunable_length(0),
@ -198,21 +201,21 @@ struct LanguageModelState {
viterbi_state_entries_length(0) {}
~LanguageModelState() {}
// Clears the viterbi search state back to its initial conditions.
/// Clears the viterbi search state back to its initial conditions.
void Clear();
void Print(const char *msg);
// Storage for the Viterbi state.
/// Storage for the Viterbi state.
ViterbiStateEntry_LIST viterbi_state_entries;
// Number and max cost of prunable paths in viterbi_state_entries.
/// Number and max cost of prunable paths in viterbi_state_entries.
int viterbi_state_entries_prunable_length;
float viterbi_state_entries_prunable_max_cost;
// Total number of entries in viterbi_state_entries.
/// Total number of entries in viterbi_state_entries.
int viterbi_state_entries_length;
};
// Bundle together all the things pertaining to the best choice/state.
/// Bundle together all the things pertaining to the best choice/state.
struct BestChoiceBundle {
explicit BestChoiceBundle(int matrix_dimension)
: updated(false), best_vse(NULL) {
@ -222,15 +225,15 @@ struct BestChoiceBundle {
}
~BestChoiceBundle() {}
// Flag to indicate whether anything was changed.
/// Flag to indicate whether anything was changed.
bool updated;
// Places to try to fix the word suggested by ambiguity checking.
/// Places to try to fix the word suggested by ambiguity checking.
DANGERR fixpt;
// The beam. One LanguageModelState containing a list of ViterbiStateEntry per
// row in the ratings matrix containing all VSEs whose BLOB_CHOICE is
// somewhere in the corresponding row.
/// The beam. One LanguageModelState containing a list of ViterbiStateEntry
/// per row in the ratings matrix containing all VSEs whose BLOB_CHOICE is
/// somewhere in the corresponding row.
PointerVector<LanguageModelState> beam;
// Best ViterbiStateEntry and BLOB_CHOICE.
/// Best ViterbiStateEntry and BLOB_CHOICE.
ViterbiStateEntry *best_vse;
};