Logo Search packages:      
Sourcecode: qrencode version File versions  Download package

qrencode.c

/*
 * qrencode - QR Code encoder
 *
 * Copyright (C) 2006, 2007, 2008 Kentaro Fukuchi <fukuchi@megaui.net>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "qrencode.h"
#include "qrencode_inner.h"
#include "qrspec.h"
#include "bitstream.h"
#include "qrinput.h"
#include "rscode.h"
#include "split.h"
#include "mask.h"

/******************************************************************************
 * Raw code
 *****************************************************************************/

static void RSblock_init(RSblock *block, int dl, unsigned char *data, int el)
{
      RS *rs;

      block->dataLength = dl;
      block->data = data;
      block->eccLength = el;
      block->ecc = (unsigned char *)malloc(el);

      rs = init_rs(8, 0x11d, 0, 1, el, 255 - dl - el);
      encode_rs_char(rs, data, block->ecc);
}

QRRawCode *QRraw_new(QRinput *input)
{
      QRRawCode *raw;
      int *spec;
      int i;
      RSblock *rsblock;
      unsigned char *p;

      p = QRinput_getByteStream(input);
      if(p == NULL) {
            return NULL;
      }

      raw = (QRRawCode *)malloc(sizeof(QRRawCode));
      raw->datacode = p;
      spec = QRspec_getEccSpec(input->version, input->level);
      raw->version = input->version;
      raw->blocks = QRspec_rsBlockNum(spec);
      raw->rsblock = (RSblock *)malloc(sizeof(RSblock) * raw->blocks);

      rsblock = raw->rsblock;
      p = raw->datacode;
      for(i=0; i<QRspec_rsBlockNum1(spec); i++) {
            RSblock_init(rsblock, QRspec_rsDataCodes1(spec), p,
                                    QRspec_rsEccCodes1(spec));
            p += QRspec_rsDataCodes1(spec);
            rsblock++;
      }
      for(i=0; i<QRspec_rsBlockNum2(spec); i++) {
            RSblock_init(rsblock, QRspec_rsDataCodes2(spec), p,
                                    QRspec_rsEccCodes2(spec));
            p += QRspec_rsDataCodes2(spec);
            rsblock++;
      }

      raw->b1 = QRspec_rsBlockNum1(spec);
      raw->dataLength = QRspec_rsBlockNum1(spec) * QRspec_rsDataCodes1(spec)
                              + QRspec_rsBlockNum2(spec) * QRspec_rsDataCodes2(spec);
      raw->eccLength = QRspec_rsBlockNum(spec) * QRspec_rsEccCodes1(spec);
      raw->count = 0;

      free(spec);

      return raw;
}

/**
 * Return a code (byte).
 * This function can be called iteratively.
 * @param raw raw code.
 * @return code
 */
unsigned char QRraw_getCode(QRRawCode *raw)
{
      int col, row;
      unsigned char ret;

      if(raw->count < raw->dataLength) {
            row = raw->count % raw->blocks;
            col = raw->count / raw->blocks;
            if(col >= raw->rsblock[row].dataLength) {
                  row += raw->b1;
            }
            ret = raw->rsblock[row].data[col];
      } else if(raw->count < raw->dataLength + raw->eccLength) {
            row = (raw->count - raw->dataLength) % raw->blocks;
            col = (raw->count - raw->dataLength) / raw->blocks;
            ret = raw->rsblock[row].ecc[col];
      } else {
            return 0;
      }
      raw->count++;
      return ret;
}

void QRraw_free(QRRawCode *raw)
{
      int i;

      free(raw->datacode);
      for(i=0; i<raw->blocks; i++) {
            free(raw->rsblock[i].ecc);
      }
      free(raw->rsblock);
      free(raw);
}

/******************************************************************************
 * Frame filling
 *****************************************************************************/

typedef struct {
      int width;
      unsigned char *frame;
      int x, y;
      int dir;
      int bit;
} FrameFiller;

static FrameFiller *FrameFiller_new(int width, unsigned char *frame)
{
      FrameFiller *filler;

      filler = (FrameFiller *)malloc(sizeof(FrameFiller));
      filler->width = width;
      filler->frame = frame;
      filler->x = width - 1;
      filler->y = width - 1;
      filler->dir = -1;
      filler->bit = -1;

      return filler;
}

static unsigned char *FrameFiller_next(FrameFiller *filler)
{
      unsigned char *p;
      int x, y, w;

      if(filler->bit == -1) {
            filler->bit = 0;
            return filler->frame + filler->y * filler->width + filler->x;
      }

      x = filler->x;
      y = filler->y;
      p = filler->frame;
      w = filler->width;

      if(filler->bit == 0) {
            x--;
            filler->bit++;
      } else {
            x++;
            y += filler->dir;
            filler->bit--;
      }

      if(filler->dir < 0) {
            if(y < 0) {
                  y = 0;
                  x -= 2;
                  filler->dir = 1;
                  if(x == 6) {
                        x--;
                        y = 9;
                  }
            }
      } else {
            if(y == w) {
                  y = w - 1;
                  x -= 2;
                  filler->dir = -1;
                  if(x == 6) {
                        x--;
                        y -= 8;
                  }
            }
      }
      if(x < 0 || y < 0) return NULL;

      filler->x = x;
      filler->y = y;

      if(p[y * w + x] & 0x80) {
            // This tail recursion could be optimized.
            return FrameFiller_next(filler);
      }
      return &p[y * w + x];
}

unsigned char *FrameFiller_fillerTest(int version)
{
      int width, length;
      unsigned char *frame, *p;
      FrameFiller *filler;
      int i, j;
      unsigned char cl = 1;
      unsigned char ch = 0;

      width = QRspec_getWidth(version);
      frame = QRspec_newFrame(version);
      filler = FrameFiller_new(width, frame);
      length = QRspec_getDataLength(version, QR_ECLEVEL_L)
                  + QRspec_getECCLength(version, QR_ECLEVEL_L);

      for(i=0; i<length; i++) {
            for(j=0; j<8; j++) {
                  p = FrameFiller_next(filler);
                  *p = ch | cl;
                  cl++;
                  if(cl == 9) {
                        cl = 1;
                        ch += 0x10;
                  }
            }
      }
      length = QRspec_getRemainder(version);
      for(i=0; i<length; i++) {
            p = FrameFiller_next(filler);
            *p = 0xa0;
      }
      p = FrameFiller_next(filler);
      free(filler);
      if(p != NULL) {
            return NULL;
      }

      return frame;
}

/******************************************************************************
 * Format information
 *****************************************************************************/

int QRcode_writeFormatInformation(int width, unsigned char *frame, int mask, QRecLevel level)
{
      unsigned int format;
      unsigned char v;
      int i;
      int blacks = 0;

      format =  QRspec_getFormatInfo(mask, level);

      for(i=0; i<8; i++) {
            if(format & 1) {
                  blacks += 2;
                  v = 0x85;
            } else {
                  v = 0x84;
            }
            frame[width * 8 + width - 1 - i] = v;
            if(i < 6) {
                  frame[width * i + 8] = v;
            } else {
                  frame[width * (i + 1) + 8] = v;
            }
            format= format >> 1;
      }
      for(i=0; i<7; i++) {
            if(format & 1) {
                  blacks += 2;
                  v = 0x85;
            } else {
                  v = 0x84;
            }
            frame[width * (width - 7 + i) + 8] = v;
            if(i == 0) {
                  frame[width * 8 + 7] = v;
            } else {
                  frame[width * 8 + 6 - i] = v;
            }
            format= format >> 1;
      }

      return blacks;
}

/******************************************************************************
 * QR-code encoding
 *****************************************************************************/

static QRcode *QRcode_new(int version, int width, unsigned char *data)
{
      QRcode *qrcode;

      qrcode = (QRcode *)malloc(sizeof(QRcode));
      qrcode->version = version;
      qrcode->width = width;
      qrcode->data = data;

      return qrcode;
}

void QRcode_free(QRcode *qrcode)
{
      if(qrcode == NULL) return;

      if(qrcode->data != NULL) {
            free(qrcode->data);
      }
      free(qrcode);
}

QRcode *QRcode_encodeMask(QRinput *input, int version, QRecLevel level, int mask)
{
      int width;
      QRRawCode *raw;
      unsigned char *frame, *masked, *p, code, bit;
      FrameFiller *filler;
      int i, j;
      QRcode *qrcode;

      QRinput_setVersion(input, version);
      QRinput_setErrorCorrectionLevel(input, level);

      raw = QRraw_new(input);
      if(raw == NULL) {
            return NULL;
      }
      version = raw->version;
      width = QRspec_getWidth(version);
      frame = QRspec_newFrame(version);
      filler = FrameFiller_new(width, frame);

      /* inteleaved data and ecc codes */
      for(i=0; i<raw->dataLength + raw->eccLength; i++) {
            code = QRraw_getCode(raw);
            bit = 0x80;
            for(j=0; j<8; j++) {
                  p = FrameFiller_next(filler);
                  *p = 0x02 | ((bit & code) != 0);
                  bit = bit >> 1;
            }
      }
      QRraw_free(raw);
      /* remainder bits */
      j = QRspec_getRemainder(version);
      for(i=0; i<j; i++) {
            p = FrameFiller_next(filler);
            *p = 0x02;
      }
      free(filler);
      /* masking */
      if(mask < 0) {
            masked = Mask_mask(width, frame, level);
      } else {
            masked = Mask_makeMask(width, frame, mask);
            QRcode_writeFormatInformation(width, masked, mask, QRinput_getErrorCorrectionLevel(input));
      }
      qrcode = QRcode_new(version, width, masked);

      free(frame);

      return qrcode;
}

QRcode *QRcode_encodeInput(QRinput *input, int version, QRecLevel level)
{
      return QRcode_encodeMask(input, version, level, -1);
}

QRcode *QRcode_encodeString8bit(const char *string, int version, QRecLevel level)
{
      QRinput *input;
      QRcode *code;

      input = QRinput_new();
      QRinput_append(input, QR_MODE_8, strlen(string), (unsigned char *)string);
      code = QRcode_encodeInput(input, version, level);
      QRinput_free(input);

      return code;
}

QRcode *QRcode_encodeString(const char *string, int version, QRecLevel level, QRencodeMode hint, int casesensitive)
{
      QRinput *input;
      QRcode *code;

      if(hint != QR_MODE_8 && hint != QR_MODE_KANJI) {
            return NULL;
      }

      input = QRinput_new();
      Split_splitStringToQRinput(string, input, version, hint, casesensitive);
      code = QRcode_encodeInput(input, version, level);
      QRinput_free(input);

      return code;
}

Generated by  Doxygen 1.6.0   Back to index