/*------------------------------------------------------------------------ * Copyright 2008-2010 (c) Jeff Brown * * 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 #include #ifdef DEBUG_PDF417 # define DEBUG_LEVEL (DEBUG_PDF417) #endif #include "debug.h" #include "decoder.h" #include "pdf417_hash.h" #define PDF417_STOP 0xbff static inline signed short pdf417_decode8 (zbar_decoder_t *dcode) { /* build edge signature of character * from similar edge measurements */ unsigned s = dcode->pdf417.s8; dbprintf(2, " s=%d ", s); if(s < 8) return(-1); long sig = 0; signed char e; unsigned char i; for(i = 0; i < 7; i++) { if(get_color(dcode) == ZBAR_SPACE) e = decode_e(get_width(dcode, i) + get_width(dcode, i + 1), s, 17); else e = decode_e(get_width(dcode, 7 - i) + get_width(dcode, 6 - i), s, 17); dbprintf(4, "%x", e); if(e < 0 || e > 8) return(-1); sig = (sig << 3) ^ e; } dbprintf(2, " sig=%06lx", sig); /* determine cluster number */ int clst = ((sig & 7) - ((sig >> 3) & 7) + ((sig >> 12) & 7) - ((sig >> 15) & 7)); if(clst < 0) clst += 9; dbprintf(2, " k=%d", clst); zassert(clst >= 0 && clst < 9, -1, "dir=%x sig=%lx k=%x %s\n", dcode->pdf417.direction, sig, clst, _zbar_decoder_buf_dump(dcode->buf, dcode->pdf417.character)); if(clst != 0 && clst != 3 && clst != 6) { if(get_color(dcode) && clst == 7 && sig == 0x080007) return(PDF417_STOP); return(-1); } signed short g[3]; sig &= 0x3ffff; g[0] = pdf417_hash[(sig - (sig >> 10)) & PDF417_HASH_MASK]; g[1] = pdf417_hash[((sig >> 8) - sig) & PDF417_HASH_MASK]; g[2] = pdf417_hash[((sig >> 14) - (sig >> 1)) & PDF417_HASH_MASK]; zassert(g[0] >= 0 && g[1] >= 0 && g[2] >= 0, -1, "dir=%x sig=%lx k=%x g0=%03x g1=%03x g2=%03x %s\n", dcode->pdf417.direction, sig, clst, g[0], g[1], g[2], _zbar_decoder_buf_dump(dcode->buf, dcode->pdf417.character)); unsigned short c = (g[0] + g[1] + g[2]) & PDF417_HASH_MASK; dbprintf(2, " g0=%x g1=%x g2=%x c=%03d(%d)", g[0], g[1], g[2], c & 0x3ff, c >> 10); return(c); } static inline signed char pdf417_decode_start(zbar_decoder_t *dcode) { unsigned s = dcode->pdf417.s8; if(s < 8) return(0); int ei = decode_e(get_width(dcode, 0) + get_width(dcode, 1), s, 17); int ex = (get_color(dcode) == ZBAR_SPACE) ? 2 : 6; if(ei != ex) return(0); ei = decode_e(get_width(dcode, 1) + get_width(dcode, 2), s, 17); if(ei) return(0); ei = decode_e(get_width(dcode, 2) + get_width(dcode, 3), s, 17); ex = (get_color(dcode) == ZBAR_SPACE) ? 0 : 2; if(ei != ex) return(0); ei = decode_e(get_width(dcode, 3) + get_width(dcode, 4), s, 17); ex = (get_color(dcode) == ZBAR_SPACE) ? 0 : 2; if(ei != ex) return(0); ei = decode_e(get_width(dcode, 4) + get_width(dcode, 5), s, 17); if(ei) return(0); ei = decode_e(get_width(dcode, 5) + get_width(dcode, 6), s, 17); if(ei) return(0); ei = decode_e(get_width(dcode, 6) + get_width(dcode, 7), s, 17); ex = (get_color(dcode) == ZBAR_SPACE) ? 7 : 1; if(ei != ex) return(0); ei = decode_e(get_width(dcode, 7) + get_width(dcode, 8), s, 17); ex = (get_color(dcode) == ZBAR_SPACE) ? 8 : 1; if(get_color(dcode) == ZBAR_BAR) { /* stop character has extra bar */ if(ei != 1) return(0); ei = decode_e(get_width(dcode, 8) + get_width(dcode, 9), s, 17); } dbprintf(2, " pdf417[%c]: s=%d", (get_color(dcode)) ? '<' : '>', s); /* check quiet zone */ if(ei >= 0 && ei < ex) { dbprintf(2, " [invalid quiet]\n"); return(0); } /* lock shared resources */ if(acquire_lock(dcode, ZBAR_PDF417)) { dbprintf(2, " [locked %d]\n", dcode->lock); return(0); } pdf417_decoder_t *dcode417 = &dcode->pdf417; dcode417->direction = get_color(dcode); dcode417->element = 0; dcode417->character = 0; dbprintf(2, " [valid start]\n"); return(ZBAR_PARTIAL); } zbar_symbol_type_t _zbar_decode_pdf417 (zbar_decoder_t *dcode) { pdf417_decoder_t *dcode417 = &dcode->pdf417; /* update latest character width */ dcode417->s8 -= get_width(dcode, 8); dcode417->s8 += get_width(dcode, 0); if(dcode417->character < 0) { pdf417_decode_start(dcode); dbprintf(4, "\n"); return(0); } /* process every 8th element of active symbol */ if(++dcode417->element) return(0); dcode417->element = 0; dbprintf(2, " pdf417[%c%02d]:", (dcode417->direction) ? '<' : '>', dcode417->character); if(get_color(dcode) != dcode417->direction) { int c = dcode417->character; release_lock(dcode, ZBAR_PDF417); dcode417->character = -1; zassert(get_color(dcode) == dcode417->direction, ZBAR_NONE, "color=%x dir=%x char=%d elem=0 %s\n", get_color(dcode), dcode417->direction, c, _zbar_decoder_buf_dump(dcode->buf, c)); } signed short c = pdf417_decode8(dcode); if(c < 0 || size_buf(dcode, dcode417->character + 1)) { dbprintf(1, (c < 0) ? " [aborted]\n" : " [overflow]\n"); release_lock(dcode, ZBAR_PDF417); dcode417->character = -1; return(0); } /* FIXME TBD infer dimensions, save codewords */ if(c == PDF417_STOP) { dbprintf(1, " [valid stop]"); /* FIXME check trailing bar and qz */ dcode->direction = 1 - 2 * dcode417->direction; dcode->modifiers = 0; release_lock(dcode, ZBAR_PDF417); dcode417->character = -1; } dbprintf(2, "\n"); return(0); }