80 lines
2.1 KiB
C
80 lines
2.1 KiB
C
#include <zbar_config.h>
|
|
#include <assert.h>
|
|
|
|
#include <zbar.h>
|
|
#include "decoder.h"
|
|
#include "zbar_utils.h"
|
|
|
|
/* at this point lengths are all decode unit offsets from the decode edge
|
|
* NB owned by finder
|
|
*/
|
|
qr_finder_line *_zbar_decoder_get_qr_finder_line (zbar_decoder_t *dcode)
|
|
{
|
|
return(&dcode->qrf.line);
|
|
}
|
|
|
|
zbar_symbol_type_t _zbar_find_qr (zbar_decoder_t *dcode)
|
|
{
|
|
qr_finder_t *qrf = &dcode->qrf;
|
|
unsigned s, qz, w;
|
|
int ei;
|
|
|
|
/* update latest finder pattern width */
|
|
qrf->s5 -= get_width(dcode, 6);
|
|
qrf->s5 += get_width(dcode, 1);
|
|
s = qrf->s5;
|
|
|
|
/*TODO: The 2005 standard allows reflectance-reversed codes (light on dark
|
|
instead of dark on light).
|
|
If we find finder patterns with the opposite polarity, we should invert
|
|
the final binarized image and use them to search for QR codes in that.*/
|
|
if(get_color(dcode) != ZBAR_SPACE || s < 7)
|
|
return(0);
|
|
|
|
QR_DBG_PRINT(" qrf: s=%d", s);
|
|
|
|
ei = decode_e(pair_width(dcode, 1), s, 7);
|
|
QR_DBG_PRINT(" %d", ei);
|
|
if(ei)
|
|
goto invalid;
|
|
|
|
ei = decode_e(pair_width(dcode, 2), s, 7);
|
|
QR_DBG_PRINT("%d", ei);
|
|
if(ei != 2)
|
|
goto invalid;
|
|
|
|
ei = decode_e(pair_width(dcode, 3), s, 7);
|
|
QR_DBG_PRINT("%d", ei);
|
|
if(ei != 2)
|
|
goto invalid;
|
|
|
|
ei = decode_e(pair_width(dcode, 4), s, 7);
|
|
QR_DBG_PRINT("%d", ei);
|
|
if(ei)
|
|
goto invalid;
|
|
|
|
/* valid QR finder symbol
|
|
* mark positions needed by decoder
|
|
*/
|
|
qz = get_width(dcode, 0);
|
|
w = get_width(dcode, 1);
|
|
qrf->line.eoffs = qz + (w + 1) / 2;
|
|
qrf->line.len = qz + w + get_width(dcode, 2);
|
|
qrf->line.pos[0] = qrf->line.len + get_width(dcode, 3);
|
|
qrf->line.pos[1] = qrf->line.pos[0];
|
|
w = get_width(dcode, 5);
|
|
qrf->line.boffs = qrf->line.pos[0] + get_width(dcode, 4) + (w + 1) / 2;
|
|
|
|
QR_DBG_PRINT(" boff=%d pos=%d len=%d eoff=%d [valid]\n",
|
|
qrf->line.boffs, qrf->line.pos[0], qrf->line.len,
|
|
qrf->line.eoffs);
|
|
|
|
dcode->direction = 0;
|
|
dcode->buflen = 0;
|
|
return(ZBAR_QRCODE);
|
|
|
|
invalid:
|
|
QR_DBG_PRINT(" [invalid]\n");
|
|
return(0);
|
|
}
|