libopenjpeg/t2.c

   1 /*
   2  * Copyright (c) 2001-2003, David Janssens
   3  * Copyright (c) 2002-2003, Yannick Verschueren
   4  * Copyright (c) 2003-2005, Francois Devaux and Antonin Descampe
   5  * Copyright (c) 2005, Herv� Drolon, FreeImage Team
   6  * Copyright (c) 2002-2005, Communications and remote sensing Laboratory, Universite catholique de Louvain, Belgium
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
  19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include "opj_includes.h"
  32
  33 /** @defgroup T2 T2 - Implementation of a tier-2 coding */
  34 /*@{*/
  35
  36 /** @name Local static functions */
  37 /*@{*/
  38
  39 static void t2_putcommacode(opj_bio_t *bio, int n);
  40 static int t2_getcommacode(opj_bio_t *bio);
  41 /**
  42 Variable length code for signalling delta Zil (truncation point)
  43 @param bio Bit Input/Output component
  44 @param n delta Zil
  45 */
  46 static void t2_putnumpasses(opj_bio_t *bio, int n);
  47 static int t2_getnumpasses(opj_bio_t *bio);
  48 /**
  49 Encode a packet of a tile to a destination buffer
  50 @param tile Tile for which to write the packets
  51 @param tcp Tile coding parameters
  52 @param pi Packet identity
  53 @param dest Destination buffer
  54 @param len Length of the destination buffer
  55 @param image_info Structure to create an index file
  56 @param tileno Number of the tile encoded
  57 @return
  58 */
  59 static int t2_encode_packet(opj_tcd_tile_t *tile, opj_tcp_t *tcp, opj_pi_iterator_t *pi, unsigned char *dest, int len, opj_image_info_t *image_info, int tileno);
  60 /**
  61 @param seg
  62 @param cblksty
  63 @param first
  64 */
  65 static void t2_init_seg(opj_tcd_seg_t *seg, int cblksty, int first);
  66 /**
  67 Decode a packet of a tile from a source buffer
  68 @param t2 T2 handle
  69 @param src Source buffer
  70 @param len Length of the source buffer
  71 @param tile Tile for which to write the packets
  72 @param tcp Tile coding parameters
  73 @param pi Packet identity
  74 @return
  75 */
  76 static int t2_decode_packet(opj_t2_t* t2, unsigned char *src, int len, opj_tcd_tile_t *tile, opj_tcp_t *tcp, opj_pi_iterator_t *pi);
  77
  78 /*@}*/
  79
  80 /*@}*/
  81
  82 /* ----------------------------------------------------------------------- */
  83
  84 /* #define RESTART 0x04 */
  85
  86 static void t2_putcommacode(opj_bio_t *bio, int n) {
  87         while (--n >= 0) {
  88                 bio_write(bio, 1, 1);
  89         }
  90         bio_write(bio, 0, 1);
  91 }
  92
  93 static int t2_getcommacode(opj_bio_t *bio) {
  94         int n;
  95         for (n = 0; bio_read(bio, 1); n++) {
  96                 ;
  97         }
  98         return n;
  99 }
 100
 101 static void t2_putnumpasses(opj_bio_t *bio, int n) {
 102         if (n == 1) {
 103                 bio_write(bio, 0, 1);
 104         } else if (n == 2) {
 105                 bio_write(bio, 2, 2);
 106         } else if (n <= 5) {
 107                 bio_write(bio, 0xc | (n - 3), 4);
 108         } else if (n <= 36) {
 109                 bio_write(bio, 0x1e0 | (n - 6), 9);
 110         } else if (n <= 164) {
 111                 bio_write(bio, 0xff80 | (n - 37), 16);
 112         }
 113 }
 114
 115 static int t2_getnumpasses(opj_bio_t *bio) {
 116         int n;
 117         if (!bio_read(bio, 1))
 118                 return 1;
 119         if (!bio_read(bio, 1))
 120                 return 2;
 121         if ((n = bio_read(bio, 2)) != 3)
 122                 return (3 + n);
 123         if ((n = bio_read(bio, 5)) != 31)
 124                 return (6 + n);
 125         return (37 + bio_read(bio, 7));
 126 }
 127
 128 static int t2_encode_packet(opj_tcd_tile_t * tile, opj_tcp_t * tcp, opj_pi_iterator_t *pi, unsigned char *dest, int len, opj_image_info_t * image_info, int tileno) {
 129         int bandno, cblkno;
 130         unsigned char *sop = 0, *eph = 0;
 131         unsigned char *c = dest;
 132
 133         int compno = pi->compno;        /* component value */
 134         int resno  = pi->resno;         /* resolution level value */
 135         int precno = pi->precno;        /* precinct value */
 136         int layno  = pi->layno;         /* quality layer value */
 137
 138         opj_tcd_tilecomp_t *tilec = &tile->comps[compno];
 139         opj_tcd_resolution_t *res = &tilec->resolutions[resno];
 140
 141         opj_bio_t *bio = NULL;  /* BIO component */
 142
 143         /* <SOP 0xff91> */
 144         if (tcp->csty & J2K_CP_CSTY_SOP) {
 145                 sop = (unsigned char *) opj_malloc(6 * sizeof(unsigned char));
 146                 sop[0] = 255;
 147                 sop[1] = 145;
 148                 sop[2] = 0;
 149                 sop[3] = 4;
 150                 sop[4] = (image_info->num % 65536) / 256;
 151                 sop[5] = (image_info->num % 65536) % 256;
 152                 memcpy(c, sop, 6);
 153                 opj_free(sop);
 154                 c += 6;
 155         }
 156         /* </SOP> */
 157
 158         if (!layno) {
 159                 for (bandno = 0; bandno < res->numbands; bandno++) {
 160                         opj_tcd_band_t *band = &res->bands[bandno];
 161                         opj_tcd_precinct_t *prc = &band->precincts[precno];
 162                         tgt_reset(prc->incltree);
 163                         tgt_reset(prc->imsbtree);
 164                         for (cblkno = 0; cblkno < prc->cw * prc->ch; cblkno++) {
 165                                 opj_tcd_cblk_t *cblk = &prc->cblks[cblkno];
 166                                 cblk->numpasses = 0;
 167                                 tgt_setvalue(prc->imsbtree, cblkno, band->numbps - cblk->numbps);
 168                         }
 169                 }
 170         }
 171
 172         bio = bio_create();
 173         bio_init_enc(bio, c, len);
 174         bio_write(bio, 1, 1);           /* Empty header bit */
 175
 176         /* Writing Packet header */
 177         for (bandno = 0; bandno < res->numbands; bandno++) {
 178                 opj_tcd_band_t *band = &res->bands[bandno];
 179                 opj_tcd_precinct_t *prc = &band->precincts[precno];
 180                 for (cblkno = 0; cblkno < prc->cw * prc->ch; cblkno++) {
 181                         opj_tcd_cblk_t *cblk = &prc->cblks[cblkno];
 182                         opj_tcd_layer_t *layer = &cblk->layers[layno];
 183                         if (!cblk->numpasses && layer->numpasses) {
 184                                 tgt_setvalue(prc->incltree, cblkno, layno);
 185                         }
 186                 }
 187                 for (cblkno = 0; cblkno < prc->cw * prc->ch; cblkno++) {
 188                         opj_tcd_cblk_t *cblk = &prc->cblks[cblkno];
 189                         opj_tcd_layer_t *layer = &cblk->layers[layno];
 190                         int increment = 0;
 191                         int nump = 0;
 192                         int len = 0, passno;
 193                         /* cblk inclusion bits */
 194                         if (!cblk->numpasses) {
 195                                 tgt_encode(bio, prc->incltree, cblkno, layno + 1);
 196                         } else {
 197                                 bio_write(bio, layer->numpasses != 0, 1);
 198                         }
 199                         /* if cblk not included, go to the next cblk  */
 200                         if (!layer->numpasses) {
 201                                 continue;
 202                         }
 203                         /* if first instance of cblk --> zero bit-planes information */
 204                         if (!cblk->numpasses) {
 205                                 cblk->numlenbits = 3;
 206                                 tgt_encode(bio, prc->imsbtree, cblkno, 999);
 207                         }
 208                         /* number of coding passes included */
 209                         t2_putnumpasses(bio, layer->numpasses);
 210
 211                         /* computation of the increase of the length indicator and insertion in the header     */
 212                         for (passno = cblk->numpasses; passno < cblk->numpasses + layer->numpasses; passno++) {
 213                                 opj_tcd_pass_t *pass = &cblk->passes[passno];
 214                                 nump++;
 215                                 len += pass->len;
 216                                 if (pass->term || passno == (cblk->numpasses + layer->numpasses) - 1) {
 217                                         increment = int_max(increment, int_floorlog2(len) + 1 - (cblk->numlenbits + int_floorlog2(nump)));
 218                                         len = 0;
 219                                         nump = 0;
 220                                 }
 221                         }
 222                         t2_putcommacode(bio, increment);
 223
 224                         /* computation of the new Length indicator */
 225                         cblk->numlenbits += increment;
 226
 227                         /* insertion of the codeword segment length */
 228                         for (passno = cblk->numpasses; passno < cblk->numpasses + layer->numpasses; passno++) {
 229                                 opj_tcd_pass_t *pass = &cblk->passes[passno];
 230                                 nump++;
 231                                 len += pass->len;
 232                                 if (pass->term || passno == (cblk->numpasses + layer->numpasses) - 1) {
 233                                         bio_write(bio, len, cblk->numlenbits + int_floorlog2(nump));
 234                                         len = 0;
 235                                         nump = 0;
 236                                 }
 237                         }
 238                 }
 239         }
 240
 241         if (bio_flush(bio)) {
 242                 return -999;            /* modified to eliminate longjmp !! */
 243         }
 244
 245         c += bio_numbytes(bio);
 246
 247         bio_destroy(bio);
 248
 249         /* <EPH 0xff92> */
 250         if (tcp->csty & J2K_CP_CSTY_EPH) {
 251                 eph = (unsigned char *) opj_malloc(2 * sizeof(unsigned char));
 252                 eph[0] = 255;
 253                 eph[1] = 146;
 254                 memcpy(c, eph, 2);
 255                 opj_free(eph);
 256                 c += 2;
 257         }
 258         /* </EPH> */
 259
 260         /* Writing the packet body */
 261
 262         for (bandno = 0; bandno < res->numbands; bandno++) {
 263                 opj_tcd_band_t *band = &res->bands[bandno];
 264                 opj_tcd_precinct_t *prc = &band->precincts[precno];
 265                 for (cblkno = 0; cblkno < prc->cw * prc->ch; cblkno++) {
 266                         opj_tcd_cblk_t *cblk = &prc->cblks[cblkno];
 267                         opj_tcd_layer_t *layer = &cblk->layers[layno];
 268                         if (!layer->numpasses) {
 269                                 continue;
 270                         }
 271                         if (c + layer->len > dest + len) {
 272                                 return -999;
 273                         }
 274
 275                         memcpy(c, layer->data, layer->len);
 276                         cblk->numpasses += layer->numpasses;
 277                         c += layer->len;
 278                         /* ADD for index Cfr. Marcela --> delta disto by packet */
 279                         if(image_info && image_info->index_write && image_info->index_on) {
 280                                 opj_tile_info_t *info_TL = &image_info->tile[tileno];
 281                                 opj_packet_info_t *info_PK = &info_TL->packet[image_info->num];
 282                                 info_PK->disto += layer->disto;
 283                                 if (image_info->D_max < info_PK->disto) {
 284                                         image_info->D_max = info_PK->disto;
 285                                 }
 286                         }
 287                         /* </ADD> */
 288                 }
 289         }
 290
 291         return (c - dest);
 292 }
 293
 294 static void t2_init_seg(opj_tcd_seg_t * seg, int cblksty, int first) {
 295         seg->numpasses = 0;
 296         seg->len = 0;
 297         if (cblksty & J2K_CCP_CBLKSTY_TERMALL) {
 298                 seg->maxpasses = 1;
 299         }
 300         else if (cblksty & J2K_CCP_CBLKSTY_LAZY) {
 301                 if (first) {
 302                         seg->maxpasses = 10;
 303                 } else {
 304                         seg->maxpasses = (((seg - 1)->maxpasses == 1) || ((seg - 1)->maxpasses == 10)) ? 2 : 1;
 305                 }
 306         } else {
 307                 seg->maxpasses = 109;
 308         }
 309 }
 310
 311 static int t2_decode_packet(opj_t2_t* t2, unsigned char *src, int len, opj_tcd_tile_t *tile, opj_tcp_t *tcp, opj_pi_iterator_t *pi) {
 312         int bandno, cblkno;
 313         unsigned char *c = src;
 314
 315         opj_cp_t *cp = t2->cp;
 316
 317         int compno = pi->compno;        /* component value */
 318         int resno  = pi->resno;         /* resolution level value */
 319         int precno = pi->precno;        /* precinct value */
 320         int layno  = pi->layno;         /* quality layer value */
 321
 322         opj_tcd_tilecomp_t *tilec = &tile->comps[compno];
 323         opj_tcd_resolution_t *res = &tilec->resolutions[resno];
 324
 325         unsigned char *hd = NULL;
 326         int present;
 327
 328         opj_bio_t *bio = NULL;  /* BIO component */
 329
 330         if (layno == 0) {
 331                 for (bandno = 0; bandno < res->numbands; bandno++) {
 332                         opj_tcd_band_t *band = &res->bands[bandno];
 333                         opj_tcd_precinct_t *prc = &band->precincts[precno];
 334
 335                         if ((band->x1-band->x0 == 0)||(band->y1-band->y0 == 0)) continue;
 336
 337                         tgt_reset(prc->incltree);
 338                         tgt_reset(prc->imsbtree);
 339                         for (cblkno = 0; cblkno < prc->cw * prc->ch; cblkno++) {
 340                                 opj_tcd_cblk_t *cblk = &prc->cblks[cblkno];
 341                                 cblk->numsegs = 0;
 342                         }
 343                 }
 344         }
 345
 346         /* SOP markers */
 347
 348         if (tcp->csty & J2K_CP_CSTY_SOP) {
 349                 if ((*c) != 0xff || (*(c + 1) != 0x91)) {
 350                         opj_event_msg(t2->cinfo, EVT_WARNING, "Expected SOP marker\n");
 351                 } else {
 352                         c += 6;
 353                 }
 354
 355                 /** TODO : check the Nsop value */
 356         }
 357
 358         /*
 359         When the marker PPT/PPM is used the packet header are store in PPT/PPM marker
 360         This part deal with this caracteristic
 361         step 1: Read packet header in the saved structure
 362         step 2: Return to codestream for decoding
 363         */
 364
 365         bio = bio_create();
 366
 367         if (cp->ppm == 1) {             /* PPM */
 368                 hd = cp->ppm_data;
 369                 bio_init_dec(bio, hd, cp->ppm_len);
 370         } else if (tcp->ppt == 1) {     /* PPT */
 371                 hd = tcp->ppt_data;
 372                 bio_init_dec(bio, hd, tcp->ppt_len);
 373         } else {                        /* Normal Case */
 374                 hd = c;
 375                 bio_init_dec(bio, hd, src+len-hd);
 376         }
 377
 378         present = bio_read(bio, 1);
 379
 380         if (!present) {
 381                 bio_inalign(bio);
 382                 hd += bio_numbytes(bio);
 383                 bio_destroy(bio);
 384
 385                 /* EPH markers */
 386
 387                 if (tcp->csty & J2K_CP_CSTY_EPH) {
 388                         if ((*hd) != 0xff || (*(hd + 1) != 0x92)) {
 389                                 printf("Error : expected EPH marker\n");
 390                         } else {
 391                                 hd += 2;
 392                         }
 393                 }
 394
 395                 if (cp->ppm == 1) {             /* PPM case */
 396                         cp->ppm_len += cp->ppm_data-hd;
 397                         cp->ppm_data = hd;
 398                         return (c - src);
 399                 }
 400                 if (tcp->ppt == 1) {    /* PPT case */
 401                         tcp->ppt_len+=tcp->ppt_data-hd;
 402                         tcp->ppt_data = hd;
 403                         return (c - src);
 404                 }
 405
 406                 return (hd - src);
 407         }
 408
 409         for (bandno = 0; bandno < res->numbands; bandno++) {
 410                 opj_tcd_band_t *band = &res->bands[bandno];
 411                 opj_tcd_precinct_t *prc = &band->precincts[precno];
 412
 413                 if ((band->x1-band->x0 == 0)||(band->y1-band->y0 == 0)) continue;
 414
 415                 for (cblkno = 0; cblkno < prc->cw * prc->ch; cblkno++) {
 416                         int included, increment, n;
 417                         opj_tcd_cblk_t *cblk = &prc->cblks[cblkno];
 418                         opj_tcd_seg_t *seg = NULL;
 419                         /* if cblk not yet included before --> inclusion tagtree */
 420                         if (!cblk->numsegs) {
 421                                 included = tgt_decode(bio, prc->incltree, cblkno, layno + 1);
 422                                 /* else one bit */
 423                         } else {
 424                                 included = bio_read(bio, 1);
 425                         }
 426                         /* if cblk not included */
 427                         if (!included) {
 428                                 cblk->numnewpasses = 0;
 429                                 continue;
 430                         }
 431                         /* if cblk not yet included --> zero-bitplane tagtree */
 432                         if (!cblk->numsegs) {
 433                                 int i, numimsbs;
 434                                 for (i = 0; !tgt_decode(bio, prc->imsbtree, cblkno, i); i++) {
 435                                         ;
 436                                 }
 437                                 numimsbs = i - 1;
 438                                 cblk->numbps = band->numbps - numimsbs;
 439                                 cblk->numlenbits = 3;
 440                         }
 441                         /* number of coding passes */
 442                         cblk->numnewpasses = t2_getnumpasses(bio);
 443                         increment = t2_getcommacode(bio);
 444                         /* length indicator increment */
 445                         cblk->numlenbits += increment;
 446                         if (!cblk->numsegs) {
 447                                 seg = &cblk->segs[0];
 448                                 t2_init_seg(seg, tcp->tccps[compno].cblksty, 1);
 449                         } else {
 450                                 seg = &cblk->segs[cblk->numsegs - 1];
 451                                 if (seg->numpasses == seg->maxpasses) {
 452                                         t2_init_seg(++seg, tcp->tccps[compno].cblksty, 0);
 453                                 }
 454                         }
 455                         n = cblk->numnewpasses;
 456
 457                         do {
 458                                 seg->numnewpasses = int_min(seg->maxpasses - seg->numpasses, n);
 459                                 seg->newlen = bio_read(bio, cblk->numlenbits + int_floorlog2(seg->numnewpasses));
 460                                 n -= seg->numnewpasses;
 461                                 if (n > 0) {
 462                                         t2_init_seg(++seg, tcp->tccps[compno].cblksty, 0);
 463                                 }
 464                         } while (n > 0);
 465                 }
 466         }
 467
 468         if (bio_inalign(bio)) {
 469                 bio_destroy(bio);
 470                 return -999;
 471         }
 472
 473         hd += bio_numbytes(bio);
 474         bio_destroy(bio);
 475
 476         /* EPH markers */
 477         if (tcp->csty & J2K_CP_CSTY_EPH) {
 478                 if ((*hd) != 0xff || (*(hd + 1) != 0x92)) {
 479                         opj_event_msg(t2->cinfo, EVT_ERROR, "Expected EPH marker\n");
 480                 } else {
 481                         hd += 2;
 482                 }
 483         }
 484
 485         if (cp->ppm==1) {
 486                 cp->ppm_len+=cp->ppm_data-hd;
 487                 cp->ppm_data = hd;
 488         } else if (tcp->ppt == 1) {
 489                 tcp->ppt_len+=tcp->ppt_data-hd;
 490                 tcp->ppt_data = hd;
 491         } else {
 492                 c=hd;
 493         }
 494
 495         for (bandno = 0; bandno < res->numbands; bandno++) {
 496                 opj_tcd_band_t *band = &res->bands[bandno];
 497                 opj_tcd_precinct_t *prc = &band->precincts[precno];
 498
 499                 if ((band->x1-band->x0 == 0)||(band->y1-band->y0 == 0)) continue;
 500
 501                 for (cblkno = 0; cblkno < prc->cw * prc->ch; cblkno++) {
 502                         opj_tcd_cblk_t *cblk = &prc->cblks[cblkno];
 503                         opj_tcd_seg_t *seg = NULL;
 504                         if (!cblk->numnewpasses)
 505                                 continue;
 506                         if (!cblk->numsegs) {
 507                                 seg = &cblk->segs[0];
 508                                 cblk->numsegs++;
 509                                 cblk->len = 0;
 510                         } else {
 511                                 seg = &cblk->segs[cblk->numsegs - 1];
 512                                 if (seg->numpasses == seg->maxpasses) {
 513                                         seg++;
 514                                         cblk->numsegs++;
 515                                 }
 516                         }
 517
 518                         do {
 519                                 if (c + seg->newlen > src + len) {
 520                                         return -999;
 521                                 }
 522
 523                                 memcpy(cblk->data + cblk->len, c, seg->newlen);
 524                                 if (seg->numpasses == 0) {
 525                                         seg->data = cblk->data + cblk->len;
 526                                 }
 527                                 c += seg->newlen;
 528                                 cblk->len += seg->newlen;
 529                                 seg->len += seg->newlen;
 530                                 seg->numpasses += seg->numnewpasses;
 531                                 cblk->numnewpasses -= seg->numnewpasses;
 532                                 if (cblk->numnewpasses > 0) {
 533                                         seg++;
 534                                         cblk->numsegs++;
 535                                 }
 536                         } while (cblk->numnewpasses > 0);
 537                 }
 538         }
 539
 540         return (c - src);
 541 }
 542
 543 /* ----------------------------------------------------------------------- */
 544
 545 int t2_encode_packets(opj_t2_t* t2, int tileno, opj_tcd_tile_t *tile, int maxlayers, unsigned char *dest, int len, opj_image_info_t *image_info) {
 546         unsigned char *c = dest;
 547         int e = 0;
 548         opj_pi_iterator_t *pi = NULL;
 549         int pino;
 550
 551         opj_image_t *image = t2->image;
 552         opj_cp_t *cp = t2->cp;
 553
 554         /* create a packet iterator */
 555         pi = pi_create(image, cp, tileno);
 556         if(!pi) {
 557                 /* TODO: throw an error */
 558                 return -999;
 559         }
 560
 561         if(image_info) {
 562                 image_info->num = 0;
 563         }
 564
 565         for (pino = 0; pino <= cp->tcps[tileno].numpocs; pino++) {
 566                 while (pi_next(&pi[pino])) {
 567                         if (pi[pino].layno < maxlayers) {
 568                                 e = t2_encode_packet(tile, &cp->tcps[tileno], &pi[pino], c, dest + len - c, image_info, tileno);
 569                                 if (e == -999) {
 570                                         break;
 571                                 } else {
 572                                         c += e;
 573                                 }
 574
 575                                 /* INDEX >> */
 576                                 if(image_info && image_info->index_on) {
 577                                         if(image_info->index_write) {
 578                                                 opj_tile_info_t *info_TL = &image_info->tile[tileno];
 579                                                 opj_packet_info_t *info_PK = &info_TL->packet[image_info->num];
 580                                                 if (!image_info->num) {
 581                                                         info_PK->start_pos = info_TL->end_header + 1;
 582                                                 } else {
 583                                                         info_PK->start_pos = info_TL->packet[image_info->num - 1].end_pos + 1;
 584                                                 }
 585                                                 info_PK->end_pos = info_PK->start_pos + e - 1;
 586                                         }
 587
 588                                         image_info->num++;
 589                                 }
 590                                 /* << INDEX */
 591                         }
 592                 }
 593         }
 594
 595         /* don't forget to release pi */
 596         pi_destroy(pi, cp, tileno);
 597
 598         if (e == -999) {
 599                 return e;
 600         }
 601
 602     return (c - dest);
 603 }
 604
 605 int t2_decode_packets(opj_t2_t *t2, unsigned char *src, int len, int tileno, opj_tcd_tile_t *tile) {
 606         unsigned char *c = src;
 607         opj_pi_iterator_t *pi;
 608         int pino, e = 0;
 609         int n = 0;
 610
 611         opj_image_t *image = t2->image;
 612         opj_cp_t *cp = t2->cp;
 613
 614         /* create a packet iterator */
 615         pi = pi_create(image, cp, tileno);
 616         if(!pi) {
 617                 /* TODO: throw an error */
 618                 return -999;
 619         }
 620
 621         for (pino = 0; pino <= cp->tcps[tileno].numpocs; pino++) {
 622                 while (pi_next(&pi[pino])) {
 623                         if ((cp->layer==0) || (cp->layer>=((pi[pino].layno)+1))) {
 624                                 e = t2_decode_packet(t2, c, src + len - c, tile, &cp->tcps[tileno], &pi[pino]);
 625                         } else {
 626                                 e = 0;
 627                         }
 628
 629                         /* progression in resolution */
 630                         image->comps[pi[pino].compno].resno_decoded =
 631                                 (e > 0) ?
 632                                 int_max(pi[pino].resno, image->comps[pi[pino].compno].resno_decoded)
 633                                 : image->comps[pi[pino].compno].resno_decoded;
 634                         n++;
 635
 636                         if (e == -999) {                /* ADD */
 637                                 break;
 638                         } else {
 639                                 c += e;
 640                         }
 641                 }
 642         }
 643
 644         /* don't forget to release pi */
 645         pi_destroy(pi, cp, tileno);
 646
 647         if (e == -999) {
 648                 return e;
 649         }
 650
 651     return (c - src);
 652 }
 653
 654 /* ----------------------------------------------------------------------- */
 655
 656 opj_t2_t* t2_create(opj_common_ptr cinfo, opj_image_t *image, opj_cp_t *cp) {
 657         /* create the tcd structure */
 658         opj_t2_t *t2 = (opj_t2_t*)opj_malloc(sizeof(opj_t2_t));
 659         if(!t2) return NULL;
 660         t2->cinfo = cinfo;
 661         t2->image = image;
 662         t2->cp = cp;
 663
 664         return t2;
 665 }
 666
 667 void t2_destroy(opj_t2_t *t2) {
 668         if(t2) {
 669                 opj_free(t2);
 670         }
 671 }
 672