/*
* qrencode - QR-code encoder
*
* Originally written by Y.Swetake
* Copyright (c)2003-2005 Y.Swetake
*
* Ported to C and modified by Kentaro Fukuchi
* 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.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "qrencode.h"
#include "qrspec.h"
#include "bitstream.h"
/******************************************************************************
* Error Correction Level
*****************************************************************************/
static QRenc_ErrorCorrectionLevel errorCorrectionLevel = QR_EC_LEVEL_L;
void QRenc_setErrorCorrectionLevel(QRenc_ErrorCorrectionLevel level)
{
errorCorrectionLevel = level;
}
QRenc_ErrorCorrectionLevel QRenc_getErrorCorrectionLevel(void)
{
return errorCorrectionLevel;
}
/******************************************************************************
* Version (size of the QR-code)
*****************************************************************************/
static int version = 0;
extern int QRenc_getVersion(void)
{
return version;
}
extern void QRenc_setVersion(int v)
{
version = v;
}
/******************************************************************************
* Input data stream
*****************************************************************************/
typedef struct _QRenc_List QRenc_List;
struct _QRenc_List {
QRenc_EncodeMode mode;
int size; ///< Size of data chunk (byte).
unsigned char *data; ///< Data chunk.
BitStream *bstream;
QRenc_List *next;
};
static QRenc_List *QRenc_newEntry(QRenc_EncodeMode mode, int size, unsigned char *data)
{
QRenc_List *entry;
entry = (QRenc_List *)malloc(sizeof(QRenc_List));
entry->mode = mode;
entry->size = size;
entry->data = (unsigned char *)malloc(size);
memcpy(entry->data, data, size);
entry->bstream = NULL;
entry->next = NULL;
return entry;
}
static QRenc_List *QRenc_freeEntry(QRenc_List *entry)
{
QRenc_List *next;
next = entry->next;
free(entry->data);
if(entry->bstream) {
BitStream_free(entry->bstream);
}
free(entry);
return next;
}
struct _QRenc_DataStream {
QRenc_List *head;
QRenc_List *tail;
};
QRenc_DataStream *QRenc_newData(void)
{
QRenc_DataStream *stream;
stream = (QRenc_DataStream *)malloc(sizeof(QRenc_DataStream));
stream->head = NULL;
stream->tail = NULL;
return stream;
}
int QRenc_appendData(QRenc_DataStream *stream, QRenc_EncodeMode mode, int size, unsigned char *data)
{
QRenc_List *entry;
entry = QRenc_newEntry(mode, size, data);
if(stream->tail == NULL) {
stream->head = entry;
stream->tail = entry;
} else {
stream->tail->next = entry;
stream->tail = entry;
}
return 0;
}
void QRenc_freeData(QRenc_DataStream *stream)
{
QRenc_List *list;
list = stream->head;
while(list != NULL) {
list = QRenc_freeEntry(list);
}
free(stream);
}
/******************************************************************************
* Estimation of the version number
*****************************************************************************/
/**
* Estimates the length of the encoded bit stream of numeric data.
* @param entry
* @return number of bits
*/
static int QRenc_estimateBitsModeNum(QRenc_List *entry)
{
int w;
int bits;
w = entry->size / 3;
bits = w * 10;
switch(entry->size - w * 3) {
case 1:
bits += 4;
break;
case 2:
bits += 7;
break;
default:
break;
}
return bits;
}
/**
* Estimates the length of the encoded bit stream of alphabet-numeric data.
* @param entry
* @return number of bits
*/
static int QRenc_estimateBitsModeAn(QRenc_List *entry)
{
int w;
int bits;
w = entry->size / 2;
bits = w * 11;
if(entry->size & 1) {
bits += 6;
}
return bits;
}
/**
* Estimates the length of the encoded bit stream of 8 bit data.
* @param entry
* @return number of bits
*/
static int QRenc_estimateBitsMode8(QRenc_List *entry)
{
return entry->size * 8;
}
/**
* Estimates the length of the encoded bit stream of kanji data.
* @param entry
* @return number of bits
*/
static int QRenc_estimateBitsModeKanji(QRenc_List *entry)
{
return (entry->size / 2) * 13;
}
/**
* Estimates the length of the encoded bit stream on the current version.
* @param entry
* @param version version of the symbol
* @return number of bits
*/
static int QRenc_estimateBitStreamSizeOfEntry(QRenc_List *entry, int version)
{
int bits = 0;
int l, m;
int num;
assert(entry != NULL);
switch(entry->mode) {
case QR_MODE_NUM:
bits = QRenc_estimateBitsModeNum(entry);
break;
case QR_MODE_AN:
bits = QRenc_estimateBitsModeAn(entry);
break;
case QR_MODE_8:
bits = QRenc_estimateBitsMode8(entry);
break;
case QR_MODE_KANJI:
bits = QRenc_estimateBitsModeKanji(entry);
break;
}
l = QRspec_lengthIndicator(entry->mode, version);
m = 1 << l;
num = (bits + m - 1) / m;
bits += num * (4 + l); // mode indicator (4bits) + length indicator
return bits;
}
/**
* Estimates the length of the encoded bit stream of the data stream.
* @param stream data stream
* @param version version of the symbol
* @return number of bits
*/
int QRenc_estimateBitStreamSize(QRenc_DataStream *stream, int version)
{
QRenc_List *list;
int bits = 0;
assert(stream != NULL);
list = stream->head;
while(list != NULL) {
bits += QRenc_estimateBitStreamSizeOfEntry(list, version);
list = list->next;
}
return bits;
}
/**
* Estimates the required version number of the symbol.
* @param stream data stream
* @return required version number
*/
static int QRenc_estimateVersion(QRenc_DataStream *stream)
{
int bits;
int new, prev;
new = 0;
do {
prev = new;
bits = QRenc_estimateBitStreamSize(stream, prev);
new = QRspec_getMinVersion((bits + 7) / 8);
if (new == -1) {
return -1;
}
} while (new > prev);
return new;
}
/******************************************************************************
* Data conversion
*****************************************************************************/
/**
* Convert the number data stream to a bit stream.
* @param entry
* @return number of bits
*/
static int QRenc_encodeModeNum(QRenc_List *entry)
{
int words;
QRenc_List *st1, *st2;
int bits1, bits2;
words = QRspec_maximumWords(QR_MODE_NUM, version);
if(words > entry->size) {
st1 = QRenc_newEntry(QR_MODE_NUM, words, entry->data);
st2 = QRenc_newEntry(QR_MODE_NUM, entry->size - words, &entry->data[words]);
bits1 = QRenc_encodeModeNum(st1);
bits2 = QRenc_encodeModeNum(st2);
entry->bstream = BitStream_new(bits1 + bits2);
BitStream_appendBitStream(entry->bstream, st1->bstream);
BitStream_appendBitStream(entry->bstream, st2->bstream);
} else {
}
}
/**
* Convert the data stream in the data chunk to a bit stream.
* @param entry
* @return number of bits
*/
static int QRenc_encodeBitStream(QRenc_List *entry)
{
assert(entry != NULL);
switch(entry->mode) {
case QR_MODE_NUM:
return QRenc_encodeModeNum(entry);
break;
case QR_MODE_AN:
// return QRenc_encodeModeAn(entry);
break;
case QR_MODE_8:
// return QRenc_encodeMode8(entry);
break;
case QR_MODE_KANJI:
// return QRenc_encodeModeKanji(entry);
break;
}
}
/**
* Convert the input data stream to a bit stream.
* @param stream input data stream.
* @return bit stream.
*/
int QRenc_createBitStream(QRenc_DataStream *stream)
{
QRenc_List *list;
int bits = 0;
BitStream *bstream;
assert(stream != NULL);
list = stream->head;
while(list != NULL) {
bits += QRenc_encodeBitStream(list);
list = list->next;
}
return bits;
}
