mirror of
https://github.com/tesseract-ocr/tesseract.git
synced 2024-12-15 17:49:29 +08:00
88 lines
3.4 KiB
C++
88 lines
3.4 KiB
C++
/**********************************************************************
|
|
* File: normstrngs.h
|
|
* Description: Utilities to normalize and manipulate UTF-32 and
|
|
* UTF-8 strings.
|
|
* Author: Ranjith Unnikrishnan
|
|
* Created: Thu July 4 2013
|
|
*
|
|
* (C) Copyright 2013, Google Inc.
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*
|
|
**********************************************************************/
|
|
|
|
#ifndef TESSERACT_CCUTIL_NORMSTRNGS_H_
|
|
#define TESSERACT_CCUTIL_NORMSTRNGS_H_
|
|
|
|
#include "genericvector.h"
|
|
#include "strngs.h"
|
|
|
|
typedef signed int char32;
|
|
|
|
namespace tesseract {
|
|
|
|
// UTF-8 to UTF-32 conversion function.
|
|
void UTF8ToUTF32(const char* utf8_str, GenericVector<char32>* str32);
|
|
|
|
// UTF-32 to UTF-8 convesion function.
|
|
void UTF32ToUTF8(const GenericVector<char32>& str32, STRING* utf8_str);
|
|
|
|
// Normalize a single char32 using NFKC + OCR-specific transformations.
|
|
// NOTE that proper NFKC may require multiple characters as input. The
|
|
// assumption of this function is that the input is already as fully composed
|
|
// as it can be, but may require some compatibility normalizations or just
|
|
// OCR evaluation related normalizations.
|
|
void NormalizeChar32(char32 ch, bool decompose, GenericVector<char32>* str);
|
|
|
|
// Normalize a UTF8 string. Same as above, but for UTF8-encoded strings, that
|
|
// can contain multiple UTF32 code points.
|
|
STRING NormalizeUTF8String(bool decompose, const char* str8);
|
|
// Default behavior is to compose, until it is proven that decomposed benefits
|
|
// at least one language.
|
|
inline STRING NormalizeUTF8String(const char* str8) {
|
|
return NormalizeUTF8String(false, str8);
|
|
}
|
|
|
|
// Apply just the OCR-specific normalizations and return the normalized char.
|
|
char32 OCRNormalize(char32 ch);
|
|
|
|
// Returns true if the OCRNormalized ch1 and ch2 are the same.
|
|
bool IsOCREquivalent(char32 ch1, char32 ch2);
|
|
|
|
// Returns true if the value lies in the range of valid unicodes.
|
|
bool IsValidCodepoint(const char32 ch);
|
|
|
|
// Returns true a code point has the White_Space Unicode property.
|
|
bool IsWhitespace(const char32 ch);
|
|
// Returns true if every char in the given (null-terminated) string has the
|
|
// White_Space Unicode property.
|
|
bool IsUTF8Whitespace(const char* text);
|
|
|
|
// Returns the length of bytes of the prefix of 'text' that have the White_Space
|
|
// unicode property.
|
|
int SpanUTF8Whitespace(const char* text);
|
|
|
|
// Returns the length of bytes of the prefix of 'text' that DO NOT have the
|
|
// White_Space unicode property.
|
|
int SpanUTF8NotWhitespace(const char* text);
|
|
|
|
// Returns true if the char is interchange valid i.e. no C0 or C1 control codes
|
|
// (other than CR LF HT FF) and no non-characters.
|
|
bool IsInterchangeValid(const char32 ch);
|
|
// Same as above but restricted to 7-bit ASCII.
|
|
bool IsInterchangeValid7BitAscii(const char32 ch);
|
|
|
|
// Convert a full-width UTF-8 string to half-width.
|
|
char32 FullwidthToHalfwidth(const char32 ch);
|
|
|
|
} // namespace tesseract
|
|
|
|
#endif // TESSERACT_CCUTIL_NORMSTRNGS_H_
|