#include <validate_grapheme.h>

Inheritance diagram for tesseract::ValidateGrapheme:

Public Member Functions
	ValidateGrapheme (ViramaScript script, bool report_errors)

	~ValidateGrapheme ()

Public Member Functions inherited from tesseract::Validator
virtual	~Validator ()

Protected Member Functions
bool	ConsumeGraphemeIfValid () override

CharClass	UnicodeToCharClass (char32 ch) const override

Protected Member Functions inherited from tesseract::Validator
	Validator (ViramaScript script, bool report_errors)

bool	ValidateCleanAndSegmentInternal (GraphemeNormMode g_mode, const std::vector< char32 > &src, std::vector< std::vector< char32 >> *dest)

void	MoveResultsToDest (GraphemeNormMode g_mode, std::vector< std::vector< char32 >> *dest)

bool	IsSubscriptScript () const

bool	CodeOnlyToOutput ()

void	MultiCodePart (int length)

bool	UseMultiCode (int length)

void	ComputeClassCodes (const std::vector< char32 > &text)

void	Clear ()

Additional Inherited Members
Static Public Member Functions inherited from tesseract::Validator
static bool	ValidateCleanAndSegment (GraphemeNormMode g_mode, bool report_errors, const std::vector< char32 > &src, std::vector< std::vector< char32 >> *dest)

static bool	IsZeroWidthMark (char32 ch)

Static Public Attributes inherited from tesseract::Validator
static const char32	kZeroWidthSpace = 0x200B

static const char32	kZeroWidthNonJoiner = 0x200C

static const char32	kZeroWidthJoiner = 0x200D

static const char32	kLeftToRightMark = 0x200E

static const char32	kRightToLeftMark = 0x200F

static const char32	kInvalid = 0xfffd

Protected Types inherited from tesseract::Validator
enum	CharClass { CharClass::kConsonant = 'C', CharClass::kVowel = 'V', CharClass::kVirama = 'H', CharClass::kMatra = 'M', CharClass::kMatraPiece = 'P', CharClass::kVowelModifier = 'D', CharClass::kZeroWidthNonJoiner = 'z', CharClass::kZeroWidthJoiner = 'Z', CharClass::kVedicMark = 'v', CharClass::kNukta = 'N', CharClass::kRobat = 'R', CharClass::kOther = 'O', CharClass::kWhitespace = ' ', CharClass::kCombiner = 'c' }

using	IndicPair = std::pair< CharClass, char32 >

Static Protected Member Functions inherited from tesseract::Validator
static std::unique_ptr< Validator >	ScriptValidator (ViramaScript script, bool report_errors)

static ViramaScript	MostFrequentViramaScript (const std::vector< char32 > &utf32)

static bool	IsVirama (char32 unicode)

static bool	IsVedicAccent (char32 unicode)

Protected Attributes inherited from tesseract::Validator
ViramaScript	script_

std::vector< IndicPair >	codes_

std::vector< std::vector< char32 > >	parts_

std::vector< char32 >	output_

int	codes_used_

int	output_used_

bool	report_errors_

Static Protected Attributes inherited from tesseract::Validator
static const int	kIndicCodePageSize = 128

static const char32	kMinIndicUnicode = 0x900

static const char32	kMaxSinhalaUnicode = 0xdff

static const char32	kMaxViramaScriptUnicode = 0x17ff

static const char32	kSinhalaVirama = 0xdca

static const char32	kMyanmarVirama = 0x1039

static const char32	kKhmerVirama = 0x17d2

static const char32	kJavaneseVirama = 0xa9c0

static const char32	kMaxJavaneseUnicode = 0xa9df

Detailed Description

Definition at line 10 of file validate_grapheme.h.

Constructor & Destructor Documentation

◆ ValidateGrapheme()

tesseract::ValidateGrapheme::ValidateGrapheme	(	ViramaScript	script,
		bool	report_errors
	)

inline

Definition at line 12 of file validate_grapheme.h.

13 : Validator(script, report_errors) {}

tesseract::Validator::Validator

Validator(ViramaScript script, bool report_errors)

Definition: validator.h:136

◆ ~ValidateGrapheme()

tesseract::ValidateGrapheme::~ValidateGrapheme ( )

inline

Definition at line 14 of file validate_grapheme.h.

14 {}

Member Function Documentation

◆ ConsumeGraphemeIfValid()

bool tesseract::ValidateGrapheme::ConsumeGraphemeIfValid ( )

overrideprotectedvirtual

Implements tesseract::Validator.

Definition at line 7 of file validate_grapheme.cpp.

                                               {
   int num_codes = codes_.size();
   char32 prev_prev_ch = ' ';
   char32 prev_ch = ' ';
   CharClass prev_cc = CharClass::kWhitespace;
   int num_codes_in_grapheme = 0;
   while (codes_used_ < num_codes) {
     CharClass cc = codes_[codes_used_].first;
     char32 ch = codes_[codes_used_].second;
     const bool is_combiner =
         cc == CharClass::kCombiner || cc == CharClass::kVirama;
     // Reject easily detected badly formed sequences.
     if (prev_cc == CharClass::kWhitespace && is_combiner) {
       if (report_errors_) tprintf("Word started with a combiner:0x%x\n", ch);
       return false;
     }
     if (prev_cc == CharClass::kVirama && cc == CharClass::kVirama) {
       if (report_errors_)
         tprintf("Two grapheme links in a row:0x%x 0x%x\n", prev_ch, ch);
       return false;
     }
     if (prev_cc != CharClass::kWhitespace && cc != CharClass::kWhitespace &&
         IsBadlyFormed(prev_ch, ch)) {
       return false;
     }
     bool prev_is_fwd_combiner =
         prev_ch == kZeroWidthJoiner || prev_cc == CharClass::kVirama ||
         (prev_ch == kZeroWidthNonJoiner &&
          (cc == CharClass::kVirama || prev_prev_ch == kZeroWidthJoiner));
     if (num_codes_in_grapheme > 0 && !is_combiner && !prev_is_fwd_combiner)
       break;
     CodeOnlyToOutput();
     ++num_codes_in_grapheme;
     prev_prev_ch = prev_ch;
     prev_ch = ch;
     prev_cc = cc;
   }
   if (num_codes_in_grapheme > 0) MultiCodePart(num_codes_in_grapheme);
   return true;
 }

◆ UnicodeToCharClass()

Validator::CharClass tesseract::ValidateGrapheme::UnicodeToCharClass ( char32 ch ) const

overrideprotectedvirtual

Implements tesseract::Validator.

Definition at line 48 of file validate_grapheme.cpp.

                                                                        {
   if (IsVedicAccent(ch)) return CharClass::kVedicMark;
   // The ZeroWidth[Non]Joiner characters are mapped to kCombiner as they
   // always combine with the previous character.
   if (u_hasBinaryProperty(ch, UCHAR_GRAPHEME_LINK)) return CharClass::kVirama;
   if (u_isUWhiteSpace(ch)) return CharClass::kWhitespace;
   // Workaround for Javanese Aksara's Taling, do not label it as a combiner
   if (ch == 0xa9ba) return CharClass::kConsonant;
   int char_type = u_charType(ch);
   if (char_type == U_NON_SPACING_MARK || char_type == U_ENCLOSING_MARK ||
       char_type == U_COMBINING_SPACING_MARK || ch == kZeroWidthNonJoiner ||
       ch == kZeroWidthJoiner)
     return CharClass::kCombiner;
   return CharClass::kOther;
 }

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

/usr/src/tesseract-ocr.master/src/training/validate_grapheme.h
/usr/src/tesseract-ocr.master/src/training/validate_grapheme.cpp

Public Member Functions

Protected Member Functions