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-rw-r--r--zbar/decoder/code39.c336
1 files changed, 336 insertions, 0 deletions
diff --git a/zbar/decoder/code39.c b/zbar/decoder/code39.c
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+++ b/zbar/decoder/code39.c
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+/*------------------------------------------------------------------------
+ * Copyright 2008-2010 (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 <string.h> /* memmove */
+
+#include <zbar.h>
+
+#ifdef DEBUG_CODE39
+#define DEBUG_LEVEL (DEBUG_CODE39)
+#endif
+#include "debug.h"
+#include "decoder.h"
+
+#define NUM_CHARS (0x2c)
+
+static const unsigned char code39_hi[32] = {
+ 0x80 | 0x00, /* 2 next */
+ 0x40 | 0x02, /* 4 */
+ 0x80 | 0x06, /* 2 next */
+ 0xc0 | 0x08, /* 2 skip */
+ 0x40 | 0x0a, /* 4 */
+ 0x80 | 0x0e, /* 2 next */
+ 0xc0 | 0x10, /* 2 skip */
+ 0x00 | 0x12, /* direct */
+
+ 0x80 | 0x13, /* 2 next */
+ 0xc0 | 0x15, /* 2 skip */
+ 0x80 | 0x17, /* 2 next */
+ 0xff, 0xc0 | 0x19, /* 2 skip */
+ 0x00 | 0x1b, /* direct */
+ 0xff, 0xff,
+
+ 0x40 | 0x1c, /* 4 */
+ 0x80 | 0x20, /* 2 next */
+ 0xc0 | 0x22, /* 2 skip */
+ 0x00 | 0x24, /* direct */
+ 0x80 | 0x25, /* 2 next */
+ 0xff, 0x00 | 0x27, /* direct */
+ 0xff,
+
+ 0xc0 | 0x28, /* 2 skip */
+ 0x00 | 0x2a, /* direct */
+ 0xff, 0xff, 0x00 | 0x2b, /* direct */
+ 0xff, 0xff, 0xff,
+};
+
+typedef struct char39_s {
+ unsigned char chk, rev, fwd;
+} char39_t;
+
+static const char39_t code39_encodings[NUM_CHARS] = {
+ { 0x07, 0x1a, 0x20 }, /* 00 */
+ { 0x0d, 0x10, 0x03 }, /* 01 */
+ { 0x13, 0x17, 0x22 }, /* 02 */
+ { 0x16, 0x1d, 0x23 }, /* 03 */
+ { 0x19, 0x0d, 0x05 }, /* 04 */
+ { 0x1c, 0x13, 0x06 }, /* 05 */
+ { 0x25, 0x07, 0x0c }, /* 06 */
+ { 0x2a, 0x2a, 0x27 }, /* 07 */
+ { 0x31, 0x04, 0x0e }, /* 08 */
+ { 0x34, 0x00, 0x0f }, /* 09 */
+ { 0x43, 0x15, 0x25 }, /* 0a */
+ { 0x46, 0x1c, 0x26 }, /* 0b */
+ { 0x49, 0x0b, 0x08 }, /* 0c */
+ { 0x4c, 0x12, 0x09 }, /* 0d */
+ { 0x52, 0x19, 0x2b }, /* 0e */
+ { 0x58, 0x0f, 0x00 }, /* 0f */
+ { 0x61, 0x02, 0x11 }, /* 10 */
+ { 0x64, 0x09, 0x12 }, /* 11 */
+ { 0x70, 0x06, 0x13 }, /* 12 */
+ { 0x85, 0x24, 0x16 }, /* 13 */
+ { 0x8a, 0x29, 0x28 }, /* 14 */
+ { 0x91, 0x21, 0x18 }, /* 15 */
+ { 0x94, 0x2b, 0x19 }, /* 16 */
+ { 0xa2, 0x28, 0x29 }, /* 17 */
+ { 0xa8, 0x27, 0x2a }, /* 18 */
+ { 0xc1, 0x1f, 0x1b }, /* 19 */
+ { 0xc4, 0x26, 0x1c }, /* 1a */
+ { 0xd0, 0x23, 0x1d }, /* 1b */
+ { 0x03, 0x14, 0x1e }, /* 1c */
+ { 0x06, 0x1b, 0x1f }, /* 1d */
+ { 0x09, 0x0a, 0x01 }, /* 1e */
+ { 0x0c, 0x11, 0x02 }, /* 1f */
+ { 0x12, 0x18, 0x21 }, /* 20 */
+ { 0x18, 0x0e, 0x04 }, /* 21 */
+ { 0x21, 0x01, 0x0a }, /* 22 */
+ { 0x24, 0x08, 0x0b }, /* 23 */
+ { 0x30, 0x05, 0x0d }, /* 24 */
+ { 0x42, 0x16, 0x24 }, /* 25 */
+ { 0x48, 0x0c, 0x07 }, /* 26 */
+ { 0x60, 0x03, 0x10 }, /* 27 */
+ { 0x81, 0x1e, 0x14 }, /* 28 */
+ { 0x84, 0x25, 0x15 }, /* 29 */
+ { 0x90, 0x22, 0x17 }, /* 2a */
+ { 0xc0, 0x20, 0x1a }, /* 2b */
+};
+
+static const unsigned char code39_characters[NUM_CHARS] =
+ "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-. $/+%*";
+
+static inline unsigned char code39_decode1(unsigned char enc, unsigned e,
+ unsigned s)
+{
+ unsigned char E = decode_e(e, s, 72);
+ if (E > 18)
+ return (0xff);
+ enc <<= 1;
+ if (E > 6) {
+ enc |= 1;
+ dbprintf(2, "1");
+ } else
+ dbprintf(2, "0");
+ return (enc);
+}
+
+static inline signed char code39_decode9(zbar_decoder_t *dcode)
+{
+ unsigned char i, enc = 0, idx;
+ const char39_t *c;
+ code39_decoder_t *dcode39 = &dcode->code39;
+
+ if (dcode39->s9 < 9)
+ return (-1);
+
+ /* threshold bar width ratios */
+ for (i = 0; i < 5; i++) {
+ enc = code39_decode1(enc, get_width(dcode, i), dcode39->s9);
+ if (enc == 0xff)
+ return (-1);
+ }
+ zassert(enc < 0x20, -1, " enc=%x s9=%x\n", enc, dcode39->s9);
+
+ /* lookup first 5 encoded widths for coarse decode */
+ idx = code39_hi[enc];
+ if (idx == 0xff)
+ return (-1);
+
+ /* encode remaining widths (NB first encoded width is lost) */
+ for (; i < 9; i++) {
+ enc = code39_decode1(enc, get_width(dcode, i), dcode39->s9);
+ if (enc == 0xff)
+ return (-1);
+ }
+
+ if ((idx & 0xc0) == 0x80)
+ idx = (idx & 0x3f) + ((enc >> 3) & 1);
+ else if ((idx & 0xc0) == 0xc0)
+ idx = (idx & 0x3f) + ((enc >> 2) & 1);
+ else if (idx & 0xc0)
+ idx = (idx & 0x3f) + ((enc >> 2) & 3);
+ zassert(idx < 0x2c, -1, " idx=%x enc=%x s9=%x\n", idx, enc, dcode39->s9);
+
+ c = &code39_encodings[idx];
+ dbprintf(2, " i=%02x chk=%02x c=%02x/%02x", idx, c->chk, c->fwd, c->rev);
+ if (enc != c->chk)
+ return (-1);
+
+ dcode39->width = dcode39->s9;
+ return ((dcode39->direction) ? c->rev : c->fwd);
+}
+
+static inline signed char code39_decode_start(zbar_decoder_t *dcode)
+{
+ signed char c;
+ unsigned quiet;
+ code39_decoder_t *dcode39 = &dcode->code39;
+ dbprintf(2, " s=%d ", dcode39->s9);
+
+ c = code39_decode9(dcode);
+ if (c != 0x19 && c != 0x2b) {
+ dbprintf(2, "\n");
+ return (ZBAR_NONE);
+ }
+ dcode39->direction ^= (c == 0x19);
+
+ /* check leading quiet zone - spec is 10x */
+ quiet = get_width(dcode, 9);
+ if (quiet && quiet < dcode39->s9 / 2) {
+ dbprintf(2, " [invalid quiet]\n");
+ return (ZBAR_NONE);
+ }
+
+ dcode39->element = 9;
+ dcode39->character = 0;
+ dbprintf(1, " dir=%x [valid start]\n", dcode39->direction);
+ return (ZBAR_PARTIAL);
+}
+
+static inline int code39_postprocess(zbar_decoder_t *dcode)
+{
+ int i;
+ code39_decoder_t *dcode39 = &dcode->code39;
+ dcode->direction = 1 - 2 * dcode39->direction;
+ if (dcode39->direction) {
+ /* reverse buffer */
+ dbprintf(2, " (rev)");
+ for (i = 0; i < dcode39->character / 2; i++) {
+ unsigned j = dcode39->character - 1 - i;
+ char code = dcode->buf[i];
+ dcode->buf[i] = dcode->buf[j];
+ dcode->buf[j] = code;
+ }
+ }
+ for (i = 0; i < dcode39->character; i++)
+ dcode->buf[i] = ((dcode->buf[i] < 0x2b) ?
+ code39_characters[(unsigned)dcode->buf[i]] :
+ '?');
+ zassert(i < dcode->buf_alloc, -1, "i=%02x %s\n", i,
+ _zbar_decoder_buf_dump(dcode->buf, dcode39->character));
+ dcode->buflen = i;
+ dcode->buf[i] = '\0';
+ dcode->modifiers = 0;
+ return (0);
+}
+
+static inline int check_width(unsigned ref, unsigned w)
+{
+ unsigned dref = ref;
+ ref *= 4;
+ w *= 4;
+ return (ref - dref <= w && w <= ref + dref);
+}
+
+zbar_symbol_type_t _zbar_decode_code39(zbar_decoder_t *dcode)
+{
+ code39_decoder_t *dcode39 = &dcode->code39;
+ signed char c;
+
+ /* update latest character width */
+ dcode39->s9 -= get_width(dcode, 9);
+ dcode39->s9 += get_width(dcode, 0);
+
+ if (dcode39->character < 0) {
+ if (get_color(dcode) != ZBAR_BAR)
+ return (ZBAR_NONE);
+ dbprintf(2, " code39:");
+ return (code39_decode_start(dcode));
+ }
+
+ if (++dcode39->element < 9)
+ return (ZBAR_NONE);
+
+ dbprintf(2, " code39[%c%02d+%x]", (dcode39->direction) ? '<' : '>',
+ dcode39->character, dcode39->element);
+
+ if (dcode39->element == 10) {
+ unsigned space = get_width(dcode, 0);
+ if (dcode39->character &&
+ dcode->buf[dcode39->character - 1] == 0x2b) { /* STOP */
+ zbar_symbol_type_t sym;
+ /* trim STOP character */
+ dcode39->character--;
+ sym = ZBAR_NONE;
+
+ /* trailing quiet zone check */
+ if (space && space < dcode39->width / 2)
+ dbprintf(2, " [invalid qz]\n");
+ else if (dcode39->character < CFG(*dcode39, ZBAR_CFG_MIN_LEN) ||
+ (CFG(*dcode39, ZBAR_CFG_MAX_LEN) > 0 &&
+ dcode39->character > CFG(*dcode39, ZBAR_CFG_MAX_LEN)))
+ dbprintf(2, " [invalid len]\n");
+ else if (!code39_postprocess(dcode)) {
+ /* FIXME checksum */
+ dbprintf(2, " [valid end]\n");
+ sym = ZBAR_CODE39;
+ }
+ dcode39->character = -1;
+ if (!sym)
+ release_lock(dcode, ZBAR_CODE39);
+ return (sym);
+ }
+ if (space > dcode39->width / 2) {
+ /* inter-character space check failure */
+ dbprintf(2, " ics>%d [invalid ics]", dcode39->width);
+ if (dcode39->character)
+ release_lock(dcode, ZBAR_CODE39);
+ dcode39->character = -1;
+ }
+ dcode39->element = 0;
+ dbprintf(2, "\n");
+ return (ZBAR_NONE);
+ }
+
+ dbprintf(2, " s=%d ", dcode39->s9);
+ if (!check_width(dcode39->width, dcode39->s9)) {
+ dbprintf(2, " [width]\n");
+ if (dcode39->character)
+ release_lock(dcode, ZBAR_CODE39);
+ dcode39->character = -1;
+ return (ZBAR_NONE);
+ }
+
+ c = code39_decode9(dcode);
+ dbprintf(2, " c=%d", c);
+
+ /* lock shared resources */
+ if (!dcode39->character && acquire_lock(dcode, ZBAR_CODE39)) {
+ dcode39->character = -1;
+ return (ZBAR_PARTIAL);
+ }
+
+ if (c < 0 || size_buf(dcode, dcode39->character + 1)) {
+ dbprintf(1, (c < 0) ? " [aborted]\n" : " [overflow]\n");
+ release_lock(dcode, ZBAR_CODE39);
+ dcode39->character = -1;
+ return (ZBAR_NONE);
+ } else {
+ zassert(c < 0x2c, ZBAR_NONE, "c=%02x s9=%x\n", c, dcode39->s9);
+ dbprintf(2, "\n");
+ }
+
+ dcode->buf[dcode39->character++] = c;
+
+ return (ZBAR_NONE);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-07 11:18:13 +0000