1 files changed, 105 insertions, 0 deletions
diff --git a/zbar/decoder/qr_finder.c b/zbar/decoder/qr_finder.c
new file mode 100644
index 0000000..c932c03
--- /dev/null
+++ b/zbar/decoder/qr_finder.c
@@ -0,0 +1,105 @@
+/*------------------------------------------------------------------------
+ *  Copyright 2009-2010 (c) Jeff Brown <spadix@users.sourceforge.net>
+ *
+ *  This file is part of the ZBar Bar Code Reader.
+ *
+ *  The ZBar Bar Code Reader is free software; you can redistribute it
+ *  and/or modify it under the terms of the GNU Lesser Public License as
+ *  published by the Free Software Foundation; either version 2.1 of
+ *  the License, or (at your option) any later version.
+ *
+ *  The ZBar Bar Code Reader 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 Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser Public License
+ *  along with the ZBar Bar Code Reader; if not, write to the Free
+ *  Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ *  Boston, MA  02110-1301  USA
+ *
+ *  http://sourceforge.net/projects/zbar
+ *------------------------------------------------------------------------*/
+
+#include "config.h"
+#include <assert.h>
+
+#include <zbar.h>
+
+#ifdef DEBUG_QR_FINDER
+#define DEBUG_LEVEL (DEBUG_QR_FINDER)
+#endif
+#include "debug.h"
+#include "decoder.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);
+
+    dbprintf(2, "    qrf: s=%d", s);
+
+    ei = decode_e(pair_width(dcode, 1), s, 7);
+    dbprintf(2, " %d", ei);
+    if (ei)
+	goto invalid;
+
+    ei = decode_e(pair_width(dcode, 2), s, 7);
+    dbprintf(2, "%d", ei);
+    if (ei != 2)
+	goto invalid;
+
+    ei = decode_e(pair_width(dcode, 3), s, 7);
+    dbprintf(2, "%d", ei);
+    if (ei != 2)
+	goto invalid;
+
+    ei = decode_e(pair_width(dcode, 4), s, 7);
+    dbprintf(2, "%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;
+
+    dbprintf(2, " 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:
+    dbprintf(2, " [invalid]\n");
+    return (0);
+}