tesseract/training/validate_myanmar.h

48 lines
1.8 KiB
C
Raw Normal View History

#ifndef TESSERACT_TRAINING_VALIDATE_MYANMAR_H_
#define TESSERACT_TRAINING_VALIDATE_MYANMAR_H_
#include "validator.h"
namespace tesseract {
// Subclass of Validator that validates and segments Myanmar.
class ValidateMyanmar : public Validator {
public:
ValidateMyanmar(ViramaScript script, bool report_errors)
: Validator(script, report_errors) {}
~ValidateMyanmar() {}
protected:
// Returns whether codes matches the pattern for a Myanmar Grapheme.
// Consumes the next Grapheme in codes_[codes_used_++...] and copies it to
// parts_ and output_. Returns true if a valid Grapheme was consumed,
// otherwise does not increment codes_used_.
bool ConsumeGraphemeIfValid() override;
// Returns the CharClass corresponding to the given Unicode ch.
Validator::CharClass UnicodeToCharClass(char32 ch) const override;
private:
// Helper consumes/copies a virama and any subscript consonant.
// Returns true if the end of input is reached.
bool ConsumeSubscriptIfPresent();
// Helper consumes/copies a series of optional signs.
// Returns true if the end of input is reached.
bool ConsumeOptionalSignsIfPresent();
// Returns true if the unicode is a Myanmar "letter" including consonants
// and independent vowels. Although table 16-3 distinguishes between some
// base consonants and vowels, the extensions make no such distinction, so we
// put them all into a single bucket.
static bool IsMyanmarLetter(char32 ch);
// Returns true if ch is a Myanmar digit or other symbol that does not take
// part in being a syllable.
static bool IsMyanmarOther(char32 ch);
// Some special unicodes used only for Myanmar processing.
static const char32 kMyanmarAsat = 0x103a;
static const char32 kMyanmarMedialYa = 0x103b;
};
} // namespace tesseract
#endif // TESSERACT_TRAINING_VALIDATE_MYANMAR_H_