zbar-windows/zbar/decoder/code128.c
2021-10-07 16:38:06 +08:00

582 lines
20 KiB
C

/*------------------------------------------------------------------------
* Copyright 2007-2010 (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_CODE128
#define DEBUG_LEVEL (DEBUG_CODE128)
#endif
#include "debug.h"
#include "decoder.h"
#define NUM_CHARS 108 /* total number of character codes */
typedef enum code128_char_e {
FNC3 = 0x60,
FNC2 = 0x61,
SHIFT = 0x62,
CODE_C = 0x63,
CODE_B = 0x64,
CODE_A = 0x65,
FNC1 = 0x66,
START_A = 0x67,
START_B = 0x68,
START_C = 0x69,
STOP_FWD = 0x6a,
STOP_REV = 0x6b,
FNC4 = 0x6c,
} code128_char_t;
static const unsigned char characters[NUM_CHARS] = {
0x5c, 0xbf, 0xa1, /* [00] 00 */
0x2a, 0xc5, 0x0c, 0xa4, /* [03] 01 */
0x2d, 0xe3, 0x0f, /* [07] 02 */
0x5f, 0xe4, /* [0a] 03 */
0x6b, 0xe8, 0x69, 0xa7, 0xe7, /* [0c] 10 */
0xc1, 0x51, 0x1e, 0x83, 0xd9, 0x00, 0x84, 0x1f, /* [11] 11 */
0xc7, 0x0d, 0x33, 0x86, 0xb5, 0x0e, 0x15, 0x87, /* [19] 12 */
0x10, 0xda, 0x11, /* [21] 13 */
0x36, 0xe5, 0x18, 0x37, /* [24] 20 */
0xcc, 0x13, 0x39, 0x89, 0x97, 0x14, 0x1b, 0x8a, 0x3a, 0xbd, /* [28] 21 */
0xa2, 0x5e, 0x01, 0x85, 0xb0, 0x02, 0xa3, /* [32] 22 */
0xa5, 0x2c, 0x16, 0x88, 0xbc, 0x12, 0xa6, /* [39] 23 */
0x61, 0xe6, 0x56, 0x62, /* [40] 30 */
0x19, 0xdb, 0x1a, /* [44] 31 */
0xa8, 0x32, 0x1c, 0x8b, 0xcd, 0x1d, 0xa9, /* [47] 32 */
0xc3, 0x20, 0xc4, /* [4e] 33 */
0x50, 0x5d, 0xc0, /* [51] 0014 0025 0034 */
0x2b, 0xc6, /* [54] 0134 0143 */
0x2e, /* [56] 0243 */
0x53, 0x60, /* [57] 0341 0352 */
0x31, /* [59] 1024 */
0x52, 0xc2, /* [5a] 1114 1134 */
0x34, 0xc8, /* [5c] 1242 1243 */
0x55, /* [5e] 1441 */
0x57, 0x3e, 0xce, /* [5f] 4100 5200 4300 */
0x3b, 0xc9, /* [62] 4310 3410 */
0x6a, /* [64] 3420 */
0x54, 0x4f, /* [65] 1430 2530 */
0x38, /* [67] 4201 */
0x58, 0xcb, /* [68] 4111 4311 */
0x2f, 0xca, /* [6a] 2421 3421 */
};
static const unsigned char lo_base[8] = { 0x00, 0x07, 0x0c, 0x19,
0x24, 0x32, 0x40, 0x47 };
static const unsigned char lo_offset[0x80] = {
0xff, 0xf0, 0xff, 0x1f, 0xff, 0xf2, 0xff, 0xff, /* 00 [00] */
0xff, 0xff, 0xff, 0x3f, 0xf4, 0xf5, 0xff, 0x6f, /* 01 */
0xff, 0xff, 0xff, 0xff, 0xf0, 0xf1, 0xff, 0x2f, /* 02 [07] */
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x3f, 0x4f, /* 03 */
0xff, 0x0f, 0xf1, 0xf2, 0xff, 0x3f, 0xff, 0xf4, /* 10 [0c] */
0xf5, 0xf6, 0xf7, 0x89, 0xff, 0xab, 0xff, 0xfc, /* 11 */
0xff, 0xff, 0x0f, 0x1f, 0x23, 0x45, 0xf6, 0x7f, /* 12 [19] */
0xff, 0xff, 0xff, 0xff, 0xf8, 0xff, 0xf9, 0xaf, /* 13 */
0xf0, 0xf1, 0xff, 0x2f, 0xff, 0xf3, 0xff, 0xff, /* 20 [24] */
0x4f, 0x5f, 0x67, 0x89, 0xfa, 0xbf, 0xff, 0xcd, /* 21 */
0xf0, 0xf1, 0xf2, 0x3f, 0xf4, 0x56, 0xff, 0xff, /* 22 [32] */
0xff, 0xff, 0x7f, 0x8f, 0x9a, 0xff, 0xbc, 0xdf, /* 23 */
0x0f, 0x1f, 0xf2, 0xff, 0xff, 0x3f, 0xff, 0xff, /* 30 [40] */
0xf4, 0xff, 0xf5, 0x6f, 0xff, 0xff, 0xff, 0xff, /* 31 */
0x0f, 0x1f, 0x23, 0xff, 0x45, 0x6f, 0xff, 0xff, /* 32 [47] */
0xf7, 0xff, 0xf8, 0x9f, 0xff, 0xff, 0xff, 0xff, /* 33 */
};
static inline signed char decode_lo(int sig)
{
unsigned char offset = (((sig >> 1) & 0x01) | ((sig >> 3) & 0x06) |
((sig >> 5) & 0x18) | ((sig >> 7) & 0x60));
unsigned char idx = lo_offset[offset];
unsigned char base, c;
if (sig & 1)
idx &= 0xf;
else
idx >>= 4;
if (idx == 0xf)
return (-1);
base = (sig >> 11) | ((sig >> 9) & 1);
zassert(base < 8, -1, "sig=%x offset=%x idx=%x base=%x\n", sig, offset, idx,
base);
idx += lo_base[base];
zassert(idx <= 0x50, -1, "sig=%x offset=%x base=%x idx=%x\n", sig, offset,
base, idx);
c = characters[idx];
dbprintf(2, " %02x(%x(%02x)/%x(%02x)) => %02x", idx, base, lo_base[base],
offset, lo_offset[offset], (unsigned char)c);
return (c);
}
static inline signed char decode_hi(int sig)
{
unsigned char rev = (sig & 0x4400) != 0;
unsigned char idx, c;
if (rev)
sig = (((sig >> 12) & 0x000f) | ((sig >> 4) & 0x00f0) |
((sig << 4) & 0x0f00) | ((sig << 12) & 0xf000));
dbprintf(2, " rev=%x", rev != 0);
switch (sig) {
case 0x0014:
idx = 0x0;
break;
case 0x0025:
idx = 0x1;
break;
case 0x0034:
idx = 0x2;
break;
case 0x0134:
idx = 0x3;
break;
case 0x0143:
idx = 0x4;
break;
case 0x0243:
idx = 0x5;
break;
case 0x0341:
idx = 0x6;
break;
case 0x0352:
idx = 0x7;
break;
case 0x1024:
idx = 0x8;
break;
case 0x1114:
idx = 0x9;
break;
case 0x1134:
idx = 0xa;
break;
case 0x1242:
idx = 0xb;
break;
case 0x1243:
idx = 0xc;
break;
case 0x1441:
idx = 0xd;
rev = 0;
break;
default:
return (-1);
}
if (rev)
idx += 0xe;
c = characters[0x51 + idx];
dbprintf(2, " %02x => %02x", idx, c);
return (c);
}
static inline unsigned char calc_check(unsigned char c)
{
if (!(c & 0x80))
return (0x18);
c &= 0x7f;
if (c < 0x3d)
return ((c < 0x30 && c != 0x17) ? 0x10 : 0x20);
if (c < 0x50)
return ((c == 0x4d) ? 0x20 : 0x10);
return ((c < 0x67) ? 0x20 : 0x10);
}
static inline signed char decode6(zbar_decoder_t *dcode)
{
int sig;
signed char c, chk;
unsigned bars;
/* build edge signature of character */
unsigned s = dcode->code128.s6;
dbprintf(2, " s=%d", s);
if (s < 5)
return (-1);
/* calculate similar edge measurements */
sig =
(get_color(dcode) == ZBAR_BAR) ?
((decode_e(get_width(dcode, 0) + get_width(dcode, 1), s, 11)
<< 12) |
(decode_e(get_width(dcode, 1) + get_width(dcode, 2), s, 11) << 8) |
(decode_e(get_width(dcode, 2) + get_width(dcode, 3), s, 11) << 4) |
(decode_e(get_width(dcode, 3) + get_width(dcode, 4), s, 11))) :
((decode_e(get_width(dcode, 5) + get_width(dcode, 4), s, 11)
<< 12) |
(decode_e(get_width(dcode, 4) + get_width(dcode, 3), s, 11) << 8) |
(decode_e(get_width(dcode, 3) + get_width(dcode, 2), s, 11) << 4) |
(decode_e(get_width(dcode, 2) + get_width(dcode, 1), s, 11)));
if (sig < 0)
return (-1);
dbprintf(2, " sig=%04x", sig);
/* lookup edge signature */
c = (sig & 0x4444) ? decode_hi(sig) : decode_lo(sig);
if (c == -1)
return (-1);
/* character validation */
bars =
(get_color(dcode) == ZBAR_BAR) ?
(get_width(dcode, 0) + get_width(dcode, 2) + get_width(dcode, 4)) :
(get_width(dcode, 1) + get_width(dcode, 3) + get_width(dcode, 5));
bars = bars * 11 * 4 / s;
chk = calc_check(c);
dbprintf(2, " bars=%d chk=%d", bars, chk);
if (chk - 7 > bars || bars > chk + 7)
return (-1);
return (c & 0x7f);
}
static inline unsigned char validate_checksum(zbar_decoder_t *dcode)
{
unsigned idx, sum, i, acc = 0;
unsigned char check, err;
code128_decoder_t *dcode128 = &dcode->code128;
if (dcode128->character < 3)
return (1);
/* add in irregularly weighted start character */
idx = (dcode128->direction) ? dcode128->character - 1 : 0;
sum = dcode->buf[idx];
if (sum >= 103)
sum -= 103;
/* calculate sum in reverse to avoid multiply operations */
for (i = dcode128->character - 3; i; i--) {
zassert(sum < 103, -1, "dir=%x i=%x sum=%x acc=%x %s\n",
dcode128->direction, i, sum, acc,
_zbar_decoder_buf_dump(dcode->buf, dcode128->character));
idx = (dcode128->direction) ? dcode128->character - 1 - i : i;
acc += dcode->buf[idx];
if (acc >= 103)
acc -= 103;
zassert(acc < 103, -1, "dir=%x i=%x sum=%x acc=%x %s\n",
dcode128->direction, i, sum, acc,
_zbar_decoder_buf_dump(dcode->buf, dcode128->character));
sum += acc;
if (sum >= 103)
sum -= 103;
}
/* and compare to check character */
idx = (dcode128->direction) ? 1 : dcode128->character - 2;
check = dcode->buf[idx];
dbprintf(2, " chk=%02x(%02x)", sum, check);
err = (sum != check);
if (err)
dbprintf(1, " [checksum error]\n");
return (err);
}
/* expand and decode character set C */
static inline unsigned postprocess_c(zbar_decoder_t *dcode, unsigned start,
unsigned end, unsigned dst)
{
unsigned i, j;
/* expand buffer to accommodate 2x set C characters (2 digits per-char) */
unsigned delta = end - start;
unsigned newlen = dcode->code128.character + delta;
if (size_buf(dcode, newlen)) {
dbprintf(2, " [overflow]\n");
return ZBAR_NONE;
}
/* relocate unprocessed data to end of buffer */
memmove(dcode->buf + start + delta, dcode->buf + start,
dcode->code128.character - start);
dcode->code128.character = newlen;
for (i = 0, j = dst; i < delta; i++, j += 2) {
/* convert each set C character into two ASCII digits */
unsigned char code = dcode->buf[start + delta + i];
dcode->buf[j] = '0';
if (code >= 50) {
code -= 50;
dcode->buf[j] += 5;
}
if (code >= 30) {
code -= 30;
dcode->buf[j] += 3;
}
if (code >= 20) {
code -= 20;
dcode->buf[j] += 2;
}
if (code >= 10) {
code -= 10;
dcode->buf[j] += 1;
}
zassert(dcode->buf[j] <= '9', delta, "start=%x end=%x i=%x j=%x %s\n",
start, end, i, j,
_zbar_decoder_buf_dump(dcode->buf, dcode->code128.character));
zassert(code <= 9, delta, "start=%x end=%x i=%x j=%x %s\n", start, end,
i, j,
_zbar_decoder_buf_dump(dcode->buf, dcode->code128.character));
dcode->buf[j + 1] = '0' + code;
}
return (delta);
}
/* resolve scan direction and convert to ASCII */
static inline unsigned char postprocess(zbar_decoder_t *dcode)
{
unsigned i, j, cexp;
unsigned char code = 0, charset;
code128_decoder_t *dcode128 = &dcode->code128;
dbprintf(2, "\n postproc len=%d", dcode128->character);
dcode->modifiers = 0;
dcode->direction = 1 - 2 * dcode128->direction;
if (dcode128->direction) {
/* reverse buffer */
dbprintf(2, " (rev)");
for (i = 0; i < dcode128->character / 2; i++) {
unsigned j = dcode128->character - 1 - i;
code = dcode->buf[i];
dcode->buf[i] = dcode->buf[j];
dcode->buf[j] = code;
}
zassert(dcode->buf[dcode128->character - 1] == STOP_REV, 1,
"dir=%x %s\n", dcode128->direction,
_zbar_decoder_buf_dump(dcode->buf, dcode->code128.character));
} else
zassert(dcode->buf[dcode128->character - 1] == STOP_FWD, 1,
"dir=%x %s\n", dcode128->direction,
_zbar_decoder_buf_dump(dcode->buf, dcode->code128.character));
code = dcode->buf[0];
zassert(code >= START_A && code <= START_C, 1, "%s\n",
_zbar_decoder_buf_dump(dcode->buf, dcode->code128.character));
charset = code - START_A;
cexp = (code == START_C) ? 1 : 0;
dbprintf(2, " start=%c", 'A' + charset);
for (i = 1, j = 0; i < dcode128->character - 2; i++) {
unsigned char code = dcode->buf[i];
zassert(!(code & 0x80), 1,
"i=%x j=%x code=%02x charset=%x cexp=%x %s\n", i, j, code,
charset, cexp,
_zbar_decoder_buf_dump(dcode->buf, dcode->code128.character));
if ((charset & 0x2) && (code < 100))
/* defer character set C for expansion */
continue;
else if (code < 0x60) {
/* convert character set B to ASCII */
code = code + 0x20;
if ((!charset || (charset == 0x81)) && (code >= 0x60))
/* convert character set A to ASCII */
code -= 0x60;
dcode->buf[j++] = code;
if (charset & 0x80)
charset &= 0x7f;
} else {
dbprintf(2, " %02x", code);
if (charset & 0x2) {
unsigned delta;
/* expand character set C to ASCII */
zassert(cexp, 1, "i=%x j=%x code=%02x charset=%x cexp=%x %s\n",
i, j, code, charset, cexp,
_zbar_decoder_buf_dump(dcode->buf,
dcode->code128.character));
delta = postprocess_c(dcode, cexp, i, j);
i += delta;
j += delta * 2;
cexp = 0;
}
if (code < CODE_C) {
if (code == SHIFT)
charset |= 0x80;
else if (code == FNC2) {
/* FIXME FNC2 - message append */
} else if (code == FNC3) {
/* FIXME FNC3 - initialize */
}
} else if (code == FNC1) {
/* FNC1 - Code 128 subsets or ASCII 0x1d */
if (i == 1)
dcode->modifiers |= MOD(ZBAR_MOD_GS1);
else if (i == 2)
dcode->modifiers |= MOD(ZBAR_MOD_AIM);
else if (i < dcode->code128.character - 3)
dcode->buf[j++] = 0x1d;
/*else drop trailing FNC1 */
} else if (code >= START_A) {
dbprintf(1, " [truncated]\n");
return (1);
} else {
unsigned char newset = CODE_A - code;
zassert(code >= CODE_C && code <= CODE_A, 1,
"i=%x j=%x code=%02x charset=%x cexp=%x %s\n", i, j,
code, charset, cexp,
_zbar_decoder_buf_dump(dcode->buf,
dcode->code128.character));
if (newset != charset)
charset = newset;
else {
/* FIXME FNC4 - extended ASCII */
}
}
if (charset & 0x2)
cexp = i + 1;
}
}
if (charset & 0x2) {
zassert(cexp, 1, "i=%x j=%x code=%02x charset=%x cexp=%x %s\n", i, j,
code, charset, cexp,
_zbar_decoder_buf_dump(dcode->buf, dcode->code128.character));
j += postprocess_c(dcode, cexp, i, j) * 2;
}
zassert(j < dcode->buf_alloc, 1, "j=%02x %s\n", j,
_zbar_decoder_buf_dump(dcode->buf, dcode->code128.character));
dcode->buflen = j;
dcode->buf[j] = '\0';
dcode->code128.character = j;
return (0);
}
zbar_symbol_type_t _zbar_decode_code128(zbar_decoder_t *dcode)
{
code128_decoder_t *dcode128 = &dcode->code128;
signed char c;
/* update latest character width */
dcode128->s6 -= get_width(dcode, 6);
dcode128->s6 += get_width(dcode, 0);
if ((dcode128->character < 0) ?
get_color(dcode) != ZBAR_SPACE :
(/* process every 6th element of active symbol */
++dcode128->element != 6 ||
/* decode color based on direction */
get_color(dcode) != dcode128->direction))
return (0);
dcode128->element = 0;
dbprintf(2, " code128[%c%02d+%x]:", (dcode128->direction) ? '<' : '>',
dcode128->character, dcode128->element);
c = decode6(dcode);
if (dcode128->character < 0) {
unsigned qz;
dbprintf(2, " c=%02x", c);
if (c < START_A || c > STOP_REV || c == STOP_FWD) {
dbprintf(2, " [invalid]\n");
return (0);
}
qz = get_width(dcode, 6);
if (qz && qz < (dcode128->s6 * 3) / 4) {
dbprintf(2, " [invalid qz %d]\n", qz);
return (0);
}
/* decoded valid start/stop */
/* initialize state */
dcode128->character = 1;
if (c == STOP_REV) {
dcode128->direction = ZBAR_BAR;
dcode128->element = 7;
} else
dcode128->direction = ZBAR_SPACE;
dcode128->start = c;
dcode128->width = dcode128->s6;
dbprintf(2, " dir=%x [valid start]\n", dcode128->direction);
return (0);
} else if (c < 0 || size_buf(dcode, dcode128->character + 1)) {
dbprintf(1, (c < 0) ? " [aborted]\n" : " [overflow]\n");
if (dcode128->character > 1)
release_lock(dcode, ZBAR_CODE128);
dcode128->character = -1;
return (0);
} else {
unsigned dw;
if (dcode128->width > dcode128->s6)
dw = dcode128->width - dcode128->s6;
else
dw = dcode128->s6 - dcode128->width;
dw *= 4;
if (dw > dcode128->width) {
dbprintf(1, " [width var]\n");
if (dcode128->character > 1)
release_lock(dcode, ZBAR_CODE128);
dcode128->character = -1;
return (0);
}
}
dcode128->width = dcode128->s6;
zassert(dcode->buf_alloc > dcode128->character, 0,
"alloc=%x idx=%x c=%02x %s\n", dcode->buf_alloc,
dcode128->character, c,
_zbar_decoder_buf_dump(dcode->buf, dcode->buf_alloc));
if (dcode128->character == 1) {
/* lock shared resources */
if (acquire_lock(dcode, ZBAR_CODE128)) {
dcode128->character = -1;
return (0);
}
dcode->buf[0] = dcode128->start;
}
dcode->buf[dcode128->character++] = c;
if (dcode128->character > 2 &&
((dcode128->direction) ? c >= START_A && c <= START_C :
c == STOP_FWD)) {
/* FIXME STOP_FWD should check extra bar (and QZ!) */
zbar_symbol_type_t sym = ZBAR_CODE128;
if (validate_checksum(dcode) || postprocess(dcode))
sym = ZBAR_NONE;
else if (dcode128->character < CFG(*dcode128, ZBAR_CFG_MIN_LEN) ||
(CFG(*dcode128, ZBAR_CFG_MAX_LEN) > 0 &&
dcode128->character > CFG(*dcode128, ZBAR_CFG_MAX_LEN))) {
dbprintf(2, " [invalid len]\n");
sym = ZBAR_NONE;
} else
dbprintf(2, " [valid end]\n");
dcode128->character = -1;
if (!sym)
release_lock(dcode, ZBAR_CODE128);
return (sym);
}
dbprintf(2, "\n");
return (0);
}