mirror of
https://github.com/tesseract-ocr/tesseract.git
synced 2024-12-28 11:08:15 +08:00
d8b1456dd5
git-svn-id: https://tesseract-ocr.googlecode.com/svn/trunk@305 d0cd1f9f-072b-0410-8dd7-cf729c803f20
86 lines
2.9 KiB
C++
86 lines
2.9 KiB
C++
///////////////////////////////////////////////////////////////////////
|
|
// File: unichar.h
|
|
// Description: Unicode character/ligature class.
|
|
// Author: Ray Smith
|
|
// Created: Wed Jun 28 17:05:01 PDT 2006
|
|
//
|
|
// (C) Copyright 2006, 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_UNICHAR_H__
|
|
#define TESSERACT_CCUTIL_UNICHAR_H__
|
|
|
|
#include <memory.h>
|
|
#include <string.h>
|
|
|
|
// Maximum number of characters that can be stored in a UNICHAR. Must be
|
|
// at least 4. Must not exceed 31 without changing the coding of length.
|
|
#define UNICHAR_LEN 24
|
|
|
|
// A UNICHAR_ID is the unique id of a unichar.
|
|
typedef int UNICHAR_ID;
|
|
|
|
// A variable to indicate an invalid or uninitialized unichar id.
|
|
static const int INVALID_UNICHAR_ID = -1;
|
|
// A special unichar that corresponds to INVALID_UNICHAR_ID.
|
|
static const char INVALID_UNICHAR[] = "__INVALID_UNICHAR__";
|
|
|
|
// The UNICHAR class holds a single classification result. This may be
|
|
// a single Unicode character (stored as between 1 and 4 utf8 bytes) or
|
|
// multple Unicode characters representing the NFKC expansion of a ligature
|
|
// such as fi, ffl etc. These are also stored as utf8.
|
|
class UNICHAR {
|
|
public:
|
|
UNICHAR() {
|
|
memset(chars, 0, UNICHAR_LEN);
|
|
}
|
|
|
|
// Construct from a utf8 string. If len<0 then the string is null terminated.
|
|
// If the string is too long to fit in the UNICHAR then it takes only what
|
|
// will fit.
|
|
UNICHAR(const char* utf8_str, int len);
|
|
|
|
// Construct from a single UCS4 character.
|
|
explicit UNICHAR(int unicode);
|
|
|
|
// Default copy constructor and operator= are OK.
|
|
|
|
// Get the first character as UCS-4.
|
|
int first_uni() const;
|
|
|
|
// Get the length of the UTF8 string.
|
|
int utf8_len() const {
|
|
int len = chars[UNICHAR_LEN - 1];
|
|
return len >=0 && len < UNICHAR_LEN ? len : UNICHAR_LEN;
|
|
}
|
|
|
|
// Get a UTF8 string, but NOT NULL terminated.
|
|
const char* utf8() const {
|
|
return chars;
|
|
}
|
|
|
|
// Get a terminated UTF8 string: Must delete[] it after use.
|
|
char* utf8_str() const;
|
|
|
|
// Get the number of bytes in the first character of the given utf8 string.
|
|
static int utf8_step(const char* utf8_str);
|
|
|
|
private:
|
|
// A UTF-8 representation of 1 or more Unicode characters.
|
|
// The last element (chars[UNICHAR_LEN - 1]) is a length if
|
|
// its value < UNICHAR_LEN, otherwise it is a genuine character.
|
|
char chars[UNICHAR_LEN];
|
|
};
|
|
|
|
#endif // TESSERACT_CCUTIL_UNICHAR_H__
|