/**
* qrencode - QR Code encoder
*
* Copyright (C) 2006 Kentaro Fukuchi
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/** \mainpage
* Libqrencode is a library for encoding data in a QR Code symbol, a kind of 2D
* symbology.
*
* <h2>Encoding</h2>
*
* There are two ways to encode data: <b>encoding a string</b> or
* <b>encoding a structured data</b>.
*
* <h3>Encoding a string</h3>
* You can encode a string by calling QRcode_encodeString().
* The given string is parsed automatically and encoded. If you want to encode
* data that can be represented as a C string style (NUL terminated), you can
* simply use this way.
*
* If the input data contains Kanji (Shift-JIS) characters and you want to
* encode them as Kanji in QR Code, you should give QR_MODE_KANJI as a hint.
* Otherwise, all of non-alphanumeric characters are encoded as 8 bit data.
*
* Please note that a C string can not contain NUL character. If your data
* contains NUL, you should chose the second way.
*
* <h3>Encoding a structured data</h3>
* You can construct a structured input data manually. If the structure of the
* input data is known, you can use this way.
* At first, you must create a ::QRinput object by QRinput_new(). Then, you can
* add input data to the QRinput object by QRinput_append().
* Finally you can call QRcode_encodeInput() to encode the QRinput data.
* You can reuse the QRinput data again to encode it in other symbols with
* different parameters.
*
* <h2>Result</h2>
* The encoded symbol is resulted as a ::QRcode object. It will contain
* its version number, width of the symbol and an array represents the symbol.
* See ::QRcode for the details. You can free the object by QRcode_free().
*
* Please note that the version of the result may be larger than specified.
* In such cases, the input data would be too large to be encoded in the
* symbol of the specified version.
*
*/
#ifndef __QRENCODE_H__
#define __QRENCODE_H__
/**
* Encoding mode.
*/
typedef enum {
QR_MODE_NUM = 0, ///< Numeric mode
QR_MODE_AN, ///< Alphabet-numeric mode
QR_MODE_8, ///< 8-bit data mode
QR_MODE_KANJI ///< Kanji (shift-jis) mode
} QRencodeMode;
/**
* Level of error correction.
*/
typedef enum {
QR_ECLEVEL_L = 0, ///< lowest
QR_ECLEVEL_M,
QR_ECLEVEL_Q,
QR_ECLEVEL_H ///< highest
} QRecLevel;
/******************************************************************************
* Input data
*****************************************************************************/
/**
* Data structure to store input data.
*/
typedef struct _QRinput QRinput;
/**
* Instantiate an input data object.
* @return input object (initialized).
*/
extern QRinput *QRinput_new(void);
/**
* Append data to the input object.
* The data is copied and appended to the input object.
* @param input input object.
* @param mode encoding mode.
* @param size size of data (byte).
* @param data a pointer to the memory area of the input data.
* @return -1 when the input data is invalid. Otherwise, return 0.
*/
extern int QRinput_append(QRinput *input, QRencodeMode mode, int size, const unsigned char *data);
/**
* Free the input object.
* All of data chunks in the input object are freed too.
* @param input input object.
*/
extern void QRinput_free(QRinput *input);
/**
* Validate the input data.
* @param mode
* @param size
* @param data
* @return result return -1 if the input is invalid. Otherwise, return 0.
*/
extern int QRinput_check(QRencodeMode mode, int size, const unsigned char *data);
/******************************************************************************
* QRcode output
*****************************************************************************/
/**
* QRcode class.
* Symbol data is represented as an array contains width*width uchars.
* Each uchar represents a module (dot). If the less significant bit of
* the uchar is 1, the corresponding module is black. The other bits are
* meaningless for usual applications, but here the specification is described.
*
* <pre>
* MSB 76543210 LSB
* |||||||`- 1=black/0=white
* ||||||`-- data and ecc code area
* |||||`--- format information
* ||||`---- version information
* |||`----- timing pattern
* ||`------ alignment pattern
* |`------- finder pattern and separator
* `-------- non-data modules (format, timing, etc.)
* </pre>
*/
typedef struct {
int version; ///< version of the symbol
int width; ///< width of the symbol
unsigned char *data; ///< symbol data
} QRcode;
/**
* Create a symbol from the input data.
* @param input input data.
* @param version version of the symbol. If 0, the library chooses the minimum
* version for the input data.
* @param level error correction level.
* @return an instance of QRcode class. The version of the result QRcode may
* be larger than the designated version.
*/
extern QRcode *QRcode_encodeInput(QRinput *input, int version, QRecLevel level);
/**
* Create a symbol from the string. The library automatically parses the input
* string and encodes in a QR Code symbol.
* @param string input string. It should be NULL terminated.
* @param version version of the symbol. If 0, the library chooses the minimum
* version for the input data.
* @param level error correction level.
* @param hint tell the library how non-alphanumerical characters should be
* encoded. If QR_MODE_KANJI is given, kanji characters will be
* encoded as Shif-JIS characters. If QR_MODE_8 is given, all of
* non-alphanumerical characters will be encoded as is. If you want
* to embed UTF-8 string, choose this.
* @return an instance of QRcode class. The version of the result QRcode may
* be larger than the designated version.
*/
extern QRcode *QRcode_encodeString(const char *string, int version, QRecLevel level, QRencodeMode hint);
/**
* Free the instance of QRcode class.
* @param qrcode an instance of QRcode class.
*/
extern void QRcode_free(QRcode *qrcode);
#endif /* __QRENCODE_H__ */
