#include <validate_indic.h>

Inheritance diagram for tesseract::ValidateIndic:

Public Member Functions
	ValidateIndic (ViramaScript script, bool report_errors)

	~ValidateIndic ()

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

Protected Member Functions
bool	ConsumeGraphemeIfValid () override

Validator::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 (unsigned length)

bool	UseMultiCode (unsigned 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_

unsigned	codes_used_

unsigned	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_indic.h.

Constructor & Destructor Documentation

◆ ValidateIndic()

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

inline

Definition at line 12 of file validate_indic.h.

13 : Validator(script, report_errors) {}

◆ ~ValidateIndic()

tesseract::ValidateIndic::~ValidateIndic ( )

inline

Definition at line 14 of file validate_indic.h.

14 {}

Member Function Documentation

◆ ConsumeGraphemeIfValid()

bool tesseract::ValidateIndic::ConsumeGraphemeIfValid ( )

overrideprotectedvirtual

Implements tesseract::Validator.

Definition at line 18 of file validate_indic.cpp.

                                            {
   switch (codes_[codes_used_].first) {
     case CharClass::kConsonant:
       return ConsumeConsonantHeadIfValid() && ConsumeConsonantTailIfValid();
     case CharClass::kVowel:
     case CharClass::kVedicMark:
       return ConsumeVowelIfValid();
     case CharClass::kZeroWidthJoiner:
     case CharClass::kZeroWidthNonJoiner:
       // Apart from within an aksara, joiners are silently dropped.
       if (report_errors_)
         tprintf("Dropping isolated joiner: 0x%x\n", codes_[codes_used_].second);
       ++codes_used_;
       return true;
     case CharClass::kOther:
       UseMultiCode(1);
       return true;
     default:
       if (report_errors_) {
         tprintf("Invalid start of grapheme sequence:%c=0x%x\n",
                 codes_[codes_used_].first, codes_[codes_used_].second);
       }
       return false;
   }
 }

◆ UnicodeToCharClass()

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

overrideprotectedvirtual

Implements tesseract::Validator.

Definition at line 44 of file validate_indic.cpp.

                                                                     {
   if (IsVedicAccent(ch)) return CharClass::kVedicMark;
   if (ch == kZeroWidthNonJoiner) return CharClass::kZeroWidthNonJoiner;
   if (ch == kZeroWidthJoiner) return CharClass::kZeroWidthJoiner;
   // Offset from the start of the relevant unicode code block aka code page.
   int base = static_cast<char32>(script_);
   int off = ch - base;
   // Anything in another code block is other.
   if (off < 0 || off >= kIndicCodePageSize) return CharClass::kOther;
   // Exception for Tamil. The aytham character is considered a letter.
   if (script_ == ViramaScript::kTamil && off == 0x03) return CharClass::kVowel;
   if (off < 0x4) return CharClass::kVowelModifier;
   if (script_ == ViramaScript::kSinhala) {
     // Sinhala is an exception.
     if (off <= 0x19) return CharClass::kVowel;
     if (off <= 0x49) return CharClass::kConsonant;
     if (off == 0x4a) return CharClass::kVirama;
     if (off <= 0x5f) return CharClass::kMatra;
   } else {
     if (off <= 0x14 || off == 0x50) return CharClass::kVowel;
     if (off <= 0x3b || (0x58 <= off && off <= 0x5f))
       return CharClass::kConsonant;
     // Sinhala doesn't have Nukta or Avagraha.
     if (off == 0x3c) return CharClass::kNukta;
     if (off == 0x3d) return CharClass::kVowel; // avagraha
     if (off <= 0x4c || (0x51 <= off && off <= 0x54)) return CharClass::kMatra;
     if (0x55 <= off && off <= 0x57) return CharClass::kMatraPiece;
     if (off == 0x4d) return CharClass::kVirama;
   }
   if (off == 0x60 || off == 0x61) return CharClass::kVowel;
   if (off == 0x62 || off == 0x63) return CharClass::kMatra;
   // Danda and digits up to 6f are OK as other.
   // 70-7f are script-specific.
   // 0BF0-0BF2 are Tamil numbers 10, 100 and 1000; treat as other.
   if (script_ == ViramaScript::kTamil && (0x70 <= off && off <= 0x72))
     return CharClass::kOther;
   // 0BF3-0BFA are other Tamil symbols.
   if (script_ == ViramaScript::kTamil && (0x73 <= off && off <= 0x7A))
     return CharClass::kOther;
   if (script_ == ViramaScript::kBengali && (off == 0x70 || off == 0x71))
     return CharClass::kConsonant;
   if (script_ == ViramaScript::kGurmukhi && (off == 0x72 || off == 0x73))
     return CharClass::kConsonant;
   if (script_ == ViramaScript::kSinhala && off == 0x70)
     return CharClass::kConsonant;
   if (script_ == ViramaScript::kDevanagari && off == 0x70)
     return CharClass::kOther;
   if (0x70 <= off && off <= 0x73) return CharClass::kVowelModifier;
   // Non Indic, Digits, Measures, danda, etc.
   return CharClass::kOther;
 }

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

/tesseract/src/training/validate_indic.h
/tesseract/src/training/validate_indic.cpp

Public Member Functions

Protected Member Functions