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/*

 * Copyright (c) 1999-2000 Image Power, Inc. and the University of

 *   British Columbia.

 * Copyright (c) 2001-2003 Michael David Adams.

 * All rights reserved.

 */

/* __START_OF_JASPER_LICENSE__

 *

 * JasPer Software License

 *

 * IMAGE POWER JPEG-2000 PUBLIC LICENSE

 * ************************************

 *

 * GRANT:

 *

 * Permission is hereby granted, free of charge, to any person (the "User")

 * obtaining a copy of this software and associated documentation, to deal

 * in the JasPer Software without restriction, including without limitation

 * the right to use, copy, modify, merge, publish, distribute, sublicense,

 * and/or sell copies of the JasPer Software (in source and binary forms),

 * and to permit persons to whom the JasPer Software is furnished to do so,

 * provided further that the License Conditions below are met.

 *

 * License Conditions

 * ******************

 *

 * A.  Redistributions of source code must retain the above copyright notice,

 * and this list of conditions, and the following disclaimer.

 *

 * B.  Redistributions in binary form must reproduce the above copyright

 * notice, and this list of conditions, and the following disclaimer in

 * the documentation and/or other materials provided with the distribution.

 *

 * C.  Neither the name of Image Power, Inc. nor any other contributor

 * (including, but not limited to, the University of British Columbia and

 * Michael David Adams) may be used to endorse or promote products derived

 * from this software without specific prior written permission.

 *

 * D.  User agrees that it shall not commence any action against Image Power,

 * Inc., the University of British Columbia, Michael David Adams, or any

 * other contributors (collectively "Licensors") for infringement of any

 * intellectual property rights ("IPR") held by the User in respect of any

 * technology that User owns or has a right to license or sublicense and

 * which is an element required in order to claim compliance with ISO/IEC

 * 15444-1 (i.e., JPEG-2000 Part 1).  "IPR" means all intellectual property

 * rights worldwide arising under statutory or common law, and whether

 * or not perfected, including, without limitation, all (i) patents and

 * patent applications owned or licensable by User; (ii) rights associated

 * with works of authorship including copyrights, copyright applications,

 * copyright registrations, mask work rights, mask work applications,

 * mask work registrations; (iii) rights relating to the protection of

 * trade secrets and confidential information; (iv) any right analogous

 * to those set forth in subsections (i), (ii), or (iii) and any other

 * proprietary rights relating to intangible property (other than trademark,

 * trade dress, or service mark rights); and (v) divisions, continuations,

 * renewals, reissues and extensions of the foregoing (as and to the extent

 * applicable) now existing, hereafter filed, issued or acquired.

 *

 * E.  If User commences an infringement action against any Licensor(s) then

 * such Licensor(s) shall have the right to terminate User's license and

 * all sublicenses that have been granted hereunder by User to other parties.

 *

 * F.  This software is for use only in hardware or software products that

 * are compliant with ISO/IEC 15444-1 (i.e., JPEG-2000 Part 1).  No license

 * or right to this Software is granted for products that do not comply

 * with ISO/IEC 15444-1.  The JPEG-2000 Part 1 standard can be purchased

 * from the ISO.

 *

 * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS LICENSE.

 * NO USE OF THE JASPER SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER

 * THIS DISCLAIMER.  THE JASPER SOFTWARE IS PROVIDED BY THE LICENSORS AND

 * CONTRIBUTORS UNDER THIS LICENSE ON AN ``AS-IS'' BASIS, WITHOUT WARRANTY

 * OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION,

 * WARRANTIES THAT THE JASPER SOFTWARE IS FREE OF DEFECTS, IS MERCHANTABLE,

 * IS FIT FOR A PARTICULAR PURPOSE OR IS NON-INFRINGING.  THOSE INTENDING

 * TO USE THE JASPER SOFTWARE OR MODIFICATIONS THEREOF FOR USE IN HARDWARE

 * OR SOFTWARE PRODUCTS ARE ADVISED THAT THEIR USE MAY INFRINGE EXISTING

 * PATENTS, COPYRIGHTS, TRADEMARKS, OR OTHER INTELLECTUAL PROPERTY RIGHTS.

 * THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE JASPER SOFTWARE

 * IS WITH THE USER.  SHOULD ANY PART OF THE JASPER SOFTWARE PROVE DEFECTIVE

 * IN ANY RESPECT, THE USER (AND NOT THE INITIAL DEVELOPERS, THE UNIVERSITY

 * OF BRITISH COLUMBIA, IMAGE POWER, INC., MICHAEL DAVID ADAMS, OR ANY

 * OTHER CONTRIBUTOR) SHALL ASSUME THE COST OF ANY NECESSARY SERVICING,

 * REPAIR OR CORRECTION.  UNDER NO CIRCUMSTANCES AND UNDER NO LEGAL THEORY,

 * WHETHER TORT (INCLUDING NEGLIGENCE), CONTRACT, OR OTHERWISE, SHALL THE

 * INITIAL DEVELOPER, THE UNIVERSITY OF BRITISH COLUMBIA, IMAGE POWER, INC.,

 * MICHAEL DAVID ADAMS, ANY OTHER CONTRIBUTOR, OR ANY DISTRIBUTOR OF THE

 * JASPER SOFTWARE, OR ANY SUPPLIER OF ANY OF SUCH PARTIES, BE LIABLE TO

 * THE USER OR ANY OTHER PERSON FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR

 * CONSEQUENTIAL DAMAGES OF ANY CHARACTER INCLUDING, WITHOUT LIMITATION,

 * DAMAGES FOR LOSS OF GOODWILL, WORK STOPPAGE, COMPUTER FAILURE OR

 * MALFUNCTION, OR ANY AND ALL OTHER COMMERCIAL DAMAGES OR LOSSES, EVEN IF

 * SUCH PARTY HAD BEEN INFORMED, OR OUGHT TO HAVE KNOWN, OF THE POSSIBILITY

 * OF SUCH DAMAGES.  THE JASPER SOFTWARE AND UNDERLYING TECHNOLOGY ARE NOT

 * FAULT-TOLERANT AND ARE NOT DESIGNED, MANUFACTURED OR INTENDED FOR USE OR

 * RESALE AS ON-LINE CONTROL EQUIPMENT IN HAZARDOUS ENVIRONMENTS REQUIRING

 * FAIL-SAFE PERFORMANCE, SUCH AS IN THE OPERATION OF NUCLEAR FACILITIES,

 * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL, DIRECT

 * LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH THE FAILURE OF THE

 * JASPER SOFTWARE OR UNDERLYING TECHNOLOGY OR PRODUCT COULD LEAD DIRECTLY

 * TO DEATH, PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE

 * ("HIGH RISK ACTIVITIES").  LICENSOR SPECIFICALLY DISCLAIMS ANY EXPRESS

 * OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES.  USER WILL NOT

 * KNOWINGLY USE, DISTRIBUTE OR RESELL THE JASPER SOFTWARE OR UNDERLYING

 * TECHNOLOGY OR PRODUCTS FOR HIGH RISK ACTIVITIES AND WILL ENSURE THAT ITS

 * CUSTOMERS AND END-USERS OF ITS PRODUCTS ARE PROVIDED WITH A COPY OF THE

 * NOTICE SPECIFIED IN THIS SECTION.

 *

 * __END_OF_JASPER_LICENSE__

 */

/*

 * Tier 2 Decoder

 *

 * $Id: jpc_t2dec.c,v 1.1 2003/05/15 01:30:32 ace Exp $

 */

/******************************************************************************\

* Includes.

\******************************************************************************/

#include <stdio.h>

#include <stdlib.h>

#include <assert.h>

#include "jas_types.h"

#include "jas_fix.h"

#include "jas_malloc.h"

#include "jas_math.h"

#include "jas_stream.h"

#include "jas_debug.h"

#include "jpc_bs.h"

#include "jpc_dec.h"

#include "jpc_cs.h"

#include "jpc_mqdec.h"

#include "jpc_t2dec.h"

#include "jpc_t1cod.h"

#include "jpc_math.h"

/******************************************************************************\

*

\******************************************************************************/

long jpc_dec_lookahead(jas_stream_t *in);

static int jpc_getcommacode(jpc_bitstream_t *in);

static int jpc_getnumnewpasses(jpc_bitstream_t *in);

static int jpc_dec_decodepkt(jpc_dec_t *dec, jas_stream_t *pkthdrstream, jas_stream_t *in, int compno, int lvlno,

  int prcno, int lyrno);

/******************************************************************************\

* Code.

\******************************************************************************/

static int jpc_getcommacode(jpc_bitstream_t *in)

{

        int n;

        int v;

        n = 0;

        for (;;) {

                if ((v = jpc_bitstream_getbit(in)) < 0) {

                        return -1;

                }

                if (jpc_bitstream_eof(in)) {

                        return -1;

                }

                if (!v) {

                        break;

                }

                ++n;

        }

        return n;

}

static int jpc_getnumnewpasses(jpc_bitstream_t *in)

{

        int n;

        if ((n = jpc_bitstream_getbit(in)) > 0) {

                if ((n = jpc_bitstream_getbit(in)) > 0) {

                        if ((n = jpc_bitstream_getbits(in, 2)) == 3) {

                                if ((n = jpc_bitstream_getbits(in, 5)) == 31) {

                                        if ((n = jpc_bitstream_getbits(in, 7)) >= 0) {

                                                n += 36 + 1;

                                        }

                                } else if (n >= 0) {

                                        n += 5 + 1;

                                }

                        } else if (n >= 0) {

                                n += 2 + 1;

                        }

                } else if (!n) {

                        n += 2;

                }

        } else if (!n) {

                ++n;

        }

        return n;

}

static int jpc_dec_decodepkt(jpc_dec_t *dec, jas_stream_t *pkthdrstream, jas_stream_t *in, int compno, int rlvlno,

  int prcno, int lyrno)

{

        jpc_bitstream_t *inb;

        jpc_dec_tcomp_t *tcomp;

        jpc_dec_rlvl_t *rlvl;

        jpc_dec_band_t *band;

        jpc_dec_cblk_t *cblk;

        int n;

        int m;

        int i;

        jpc_tagtreenode_t *leaf;

        int included;

        int ret;

        int numnewpasses;

        jpc_dec_seg_t *seg;

        int len;

        int present;

        int savenumnewpasses;

        int mycounter;

        jpc_ms_t *ms;

        jpc_dec_tile_t *tile;

        jpc_dec_ccp_t *ccp;

        jpc_dec_cp_t *cp;

        int bandno;

        jpc_dec_prc_t *prc;

        int usedcblkcnt;

        int cblkno;

        uint_fast32_t bodylen;

        bool discard;

        int passno;

        int maxpasses;

        int hdrlen;

        int hdroffstart;

        int hdroffend;

        /* Avoid compiler warning about possible use of uninitialized

          variable. */

        bodylen = 0;

        discard = (lyrno >= dec->maxlyrs);

        tile = dec->curtile;

        cp = tile->cp;

        ccp = &cp->ccps[compno];

        /*

         * Decode the packet header.

         */

        /* Decode the SOP marker segment if present. */

        if (cp->csty & JPC_COD_SOP) {

                if (jpc_dec_lookahead(in) == JPC_MS_SOP) {

                        if (!(ms = jpc_getms(in, dec->cstate))) {

                                return -1;

                        }

                        if (jpc_ms_gettype(ms) != JPC_MS_SOP) {

                                jpc_ms_destroy(ms);

                                fprintf(stderr, "missing SOP marker segment\n");

                                return -1;

                        }

                        jpc_ms_destroy(ms);

                }

        }

hdroffstart = jas_stream_getrwcount(pkthdrstream);

        if (!(inb = jpc_bitstream_sopen(pkthdrstream, "r"))) {

                return -1;

        }

        if ((present = jpc_bitstream_getbit(inb)) < 0) {

                return 1;

        }

        JAS_DBGLOG(10, ("\n", present));

        JAS_DBGLOG(10, ("present=%d ", present));

        /* Is the packet non-empty? */

        if (present) {

                /* The packet is non-empty. */

                tcomp = &tile->tcomps[compno];

                rlvl = &tcomp->rlvls[rlvlno];

                bodylen = 0;

                for (bandno = 0, band = rlvl->bands; bandno < rlvl->numbands;

                  ++bandno, ++band) {

                        if (!band->data) {

                                continue;

                        }

                        prc = &band->prcs[prcno];

                        if (!prc->cblks) {

                                continue;

                        }

                        usedcblkcnt = 0;

                        for (cblkno = 0, cblk = prc->cblks; cblkno < prc->numcblks;

                          ++cblkno, ++cblk) {

                                ++usedcblkcnt;

                                if (!cblk->numpasses) {

                                        leaf = jpc_tagtree_getleaf(prc->incltagtree, usedcblkcnt - 1);

                                        if ((included = jpc_tagtree_decode(prc->incltagtree, leaf, lyrno + 1, inb)) < 0) {

                                                return -1;

                                        }

                                } else {

                                        if ((included = jpc_bitstream_getbit(inb)) < 0) {

                                                return -1;

                                        }

                                }

                                JAS_DBGLOG(10, ("\n"));

                                JAS_DBGLOG(10, ("included=%d ", included));

                                if (!included) {

                                        continue;

                                }

                                if (!cblk->numpasses) {

                                        i = 1;

                                        leaf = jpc_tagtree_getleaf(prc->numimsbstagtree, usedcblkcnt - 1);

                                        for (;;) {

                                                if ((ret = jpc_tagtree_decode(prc->numimsbstagtree, leaf, i, inb)) < 0) {

                                                        return -1;

                                                }

                                                if (ret) {

                                                        break;

                                                }

                                                ++i;

                                        }

                                        cblk->numimsbs = i - 1;

                                        cblk->firstpassno = cblk->numimsbs * 3;

                                }

                                if ((numnewpasses = jpc_getnumnewpasses(inb)) < 0) {

                                        return -1;

                                }

                                JAS_DBGLOG(10, ("numnewpasses=%d ", numnewpasses));

                                seg = cblk->curseg;

                                savenumnewpasses = numnewpasses;

                                mycounter = 0;

                                if (numnewpasses > 0) {

                                        if ((m = jpc_getcommacode(inb)) < 0) {

                                                return -1;

                                        }

                                        cblk->numlenbits += m;

                                        JAS_DBGLOG(10, ("increment=%d ", m));

                                        while (numnewpasses > 0) {

                                                passno = cblk->firstpassno + cblk->numpasses + mycounter;

        /* XXX - the maxpasses is not set precisely but this doesn't matter... */

                                                maxpasses = JPC_SEGPASSCNT(passno, cblk->firstpassno, 10000, (ccp->cblkctx & JPC_COX_LAZY) != 0, (ccp->cblkctx & JPC_COX_TERMALL) != 0);

                                                if (!discard && !seg) {

                                                        if (!(seg = jpc_seg_alloc())) {

                                                                return -1;

                                                        }

                                                        jpc_seglist_insert(&cblk->segs, cblk->segs.tail, seg);

                                                        if (!cblk->curseg) {

                                                                cblk->curseg = seg;

                                                        }

                                                        seg->passno = passno;

                                                        seg->type = JPC_SEGTYPE(seg->passno, cblk->firstpassno, (ccp->cblkctx & JPC_COX_LAZY) != 0);

                                                        seg->maxpasses = maxpasses;

                                                }

                                                n = JAS_MIN(numnewpasses, maxpasses);

                                                mycounter += n;

                                                numnewpasses -= n;

                                                if ((len = jpc_bitstream_getbits(inb, cblk->numlenbits + jpc_floorlog2(n))) < 0) {

                                                        return -1;

                                                }

                                                JAS_DBGLOG(10, ("len=%d ", len));

                                                if (!discard) {

                                                        seg->lyrno = lyrno;

                                                        seg->numpasses += n;

                                                        seg->cnt = len;

                                                        seg = seg->next;

                                                }

                                                bodylen += len;

                                        }

                                }

                                cblk->numpasses += savenumnewpasses;

                        }

                }

                jpc_bitstream_inalign(inb, 0, 0);

        } else {

                if (jpc_bitstream_inalign(inb, 0x7f, 0)) {

                        fprintf(stderr, "alignment failed\n");

                        return -1;

                }

        }

        jpc_bitstream_close(inb);

        hdroffend = jas_stream_getrwcount(pkthdrstream);

        hdrlen = hdroffend - hdroffstart;

        if (jas_getdbglevel() >= 5) {

                fprintf(stderr, "hdrlen=%lu bodylen=%lu \n", (unsigned long) hdrlen,

                  (unsigned long) bodylen);

        }

        if (cp->csty & JPC_COD_EPH) {

                if (jpc_dec_lookahead(pkthdrstream) == JPC_MS_EPH) {

                        if (!(ms = jpc_getms(pkthdrstream, dec->cstate))) {

                                fprintf(stderr, "cannot get (EPH) marker segment\n");

                                return -1;

                        }

                        if (jpc_ms_gettype(ms) != JPC_MS_EPH) {

                                jpc_ms_destroy(ms);

                                fprintf(stderr, "missing EPH marker segment\n");

                                return -1;

                        }

                        jpc_ms_destroy(ms);

                }

        }

        /* decode the packet body. */

        if (jas_getdbglevel() >= 1) {

                fprintf(stderr, "packet body offset=%06ld\n", (long) jas_stream_getrwcount(in));

        }

        if (!discard) {

                tcomp = &tile->tcomps[compno];

                rlvl = &tcomp->rlvls[rlvlno];

                for (bandno = 0, band = rlvl->bands; bandno < rlvl->numbands;

                  ++bandno, ++band) {

                        if (!band->data) {

                                continue;

                        }

                        prc = &band->prcs[prcno];

                        if (!prc->cblks) {

                                continue;

                        }

                        for (cblkno = 0, cblk = prc->cblks; cblkno < prc->numcblks;

                          ++cblkno, ++cblk) {

                                seg = cblk->curseg;

                                while (seg) {

                                        if (!seg->stream) {

                                                if (!(seg->stream = jas_stream_memopen(0, 0))) {

                                                        return -1;

                                                }

                                        }

#if 0

fprintf(stderr, "lyrno=%02d, compno=%02d, lvlno=%02d, prcno=%02d, bandno=%02d, cblkno=%02d, passno=%02d numpasses=%02d cnt=%d numbps=%d, numimsbs=%d\n", lyrno, compno, rlvlno, prcno, band - rlvl->bands, cblk - prc->cblks, seg->passno, seg->numpasses, seg->cnt, band->numbps, cblk->numimsbs);

#endif

                                        if (seg->cnt > 0) {

                                                if (jpc_getdata(in, seg->stream, seg->cnt) < 0) {

                                                        return -1;

                                                }

                                                seg->cnt = 0;

                                        }

                                        if (seg->numpasses >= seg->maxpasses) {

                                                cblk->curseg = seg->next;

                                        }

                                        seg = seg->next;

                                }

                        }

                }

        } else {

                if (jas_stream_gobble(in, bodylen) != JAS_CAST(int, bodylen)) {

                        return -1;

                }

        }

        return 0;

}

/********************************************************************************************/

/********************************************************************************************/

int jpc_dec_decodepkts(jpc_dec_t *dec, jas_stream_t *pkthdrstream, jas_stream_t *in)

{

        jpc_dec_tile_t *tile;

        jpc_pi_t *pi;

        int ret;

        tile = dec->curtile;

        pi = tile->pi;

        for (;;) {

if (!tile->pkthdrstream || jas_stream_peekc(tile->pkthdrstream) == EOF) {

                switch (jpc_dec_lookahead(in)) {

                case JPC_MS_EOC:

                case JPC_MS_SOT:

                        return 0;

                        break;

                case JPC_MS_SOP:

                case JPC_MS_EPH:

                case 0:

                        break;

                default:

                        return -1;

                        break;

                }

}

                if ((ret = jpc_pi_next(pi))) {

                        return ret;

                }

if (dec->maxpkts >= 0 && dec->numpkts >= dec->maxpkts) {

        fprintf(stderr, "warning: stopping decode prematurely as requested\n");

        return 0;

}

                if (jas_getdbglevel() >= 1) {

                        fprintf(stderr, "packet offset=%08ld prg=%d cmptno=%02d "

                          "rlvlno=%02d prcno=%03d lyrno=%02d\n", (long)

                          jas_stream_getrwcount(in), jpc_pi_prg(pi), jpc_pi_cmptno(pi),

                          jpc_pi_rlvlno(pi), jpc_pi_prcno(pi), jpc_pi_lyrno(pi));

                }

                if (jpc_dec_decodepkt(dec, pkthdrstream, in, jpc_pi_cmptno(pi), jpc_pi_rlvlno(pi),

                  jpc_pi_prcno(pi), jpc_pi_lyrno(pi))) {

                        return -1;

                }

++dec->numpkts;

        }

        return 0;

}

jpc_pi_t *jpc_dec_pi_create(jpc_dec_t *dec, jpc_dec_tile_t *tile)

{

        jpc_pi_t *pi;

        int compno;

        jpc_picomp_t *picomp;

        jpc_pirlvl_t *pirlvl;

        jpc_dec_tcomp_t *tcomp;

        int rlvlno;

        jpc_dec_rlvl_t *rlvl;

        int prcno;

        int *prclyrno;

        jpc_dec_cmpt_t *cmpt;

        if (!(pi = jpc_pi_create0())) {

                return 0;

        }

        pi->numcomps = dec->numcomps;

        if (!(pi->picomps = jas_malloc(pi->numcomps * sizeof(jpc_picomp_t)))) {

                jpc_pi_destroy(pi);

                return 0;

        }

        for (compno = 0, picomp = pi->picomps; compno < pi->numcomps; ++compno,

          ++picomp) {

                picomp->pirlvls = 0;

        }

        for (compno = 0, tcomp = tile->tcomps, picomp = pi->picomps;

          compno < pi->numcomps; ++compno, ++tcomp, ++picomp) {

                picomp->numrlvls = tcomp->numrlvls;

                if (!(picomp->pirlvls = jas_malloc(picomp->numrlvls *

                  sizeof(jpc_pirlvl_t)))) {

                        jpc_pi_destroy(pi);

                        return 0;

                }

                for (rlvlno = 0, pirlvl = picomp->pirlvls; rlvlno <

                  picomp->numrlvls; ++rlvlno, ++pirlvl) {

                        pirlvl->prclyrnos = 0;

                }

                for (rlvlno = 0, pirlvl = picomp->pirlvls, rlvl = tcomp->rlvls;

                  rlvlno < picomp->numrlvls; ++rlvlno, ++pirlvl, ++rlvl) {

/* XXX sizeof(long) should be sizeof different type */

                        pirlvl->numprcs = rlvl->numprcs;

                        if (!(pirlvl->prclyrnos = jas_malloc(pirlvl->numprcs *

                          sizeof(long)))) {

                                jpc_pi_destroy(pi);

                                return 0;

                        }

                }

        }

        pi->maxrlvls = 0;

        for (compno = 0, tcomp = tile->tcomps, picomp = pi->picomps, cmpt =

          dec->cmpts; compno < pi->numcomps; ++compno, ++tcomp, ++picomp,

          ++cmpt) {

                picomp->hsamp = cmpt->hstep;

                picomp->vsamp = cmpt->vstep;

                for (rlvlno = 0, pirlvl = picomp->pirlvls, rlvl = tcomp->rlvls;

                  rlvlno < picomp->numrlvls; ++rlvlno, ++pirlvl, ++rlvl) {

                        pirlvl->prcwidthexpn = rlvl->prcwidthexpn;

                        pirlvl->prcheightexpn = rlvl->prcheightexpn;

                        for (prcno = 0, prclyrno = pirlvl->prclyrnos;

                          prcno < pirlvl->numprcs; ++prcno, ++prclyrno) {

                                *prclyrno = 0;

                        }

                        pirlvl->numhprcs = rlvl->numhprcs;

                }

                if (pi->maxrlvls < tcomp->numrlvls) {

                        pi->maxrlvls = tcomp->numrlvls;

                }

        }

        pi->numlyrs = tile->cp->numlyrs;

        pi->xstart = tile->xstart;

        pi->ystart = tile->ystart;

        pi->xend = tile->xend;

        pi->yend = tile->yend;

        pi->picomp = 0;

        pi->pirlvl = 0;

        pi->x = 0;

        pi->y = 0;

        pi->compno = 0;

        pi->rlvlno = 0;

        pi->prcno = 0;

        pi->lyrno = 0;

        pi->xstep = 0;

        pi->ystep = 0;

        pi->pchgno = -1;

        pi->defaultpchg.prgord = tile->cp->prgord;

        pi->defaultpchg.compnostart = 0;

        pi->defaultpchg.compnoend = pi->numcomps;

        pi->defaultpchg.rlvlnostart = 0;

        pi->defaultpchg.rlvlnoend = pi->maxrlvls;

        pi->defaultpchg.lyrnoend = pi->numlyrs;

        pi->pchg = 0;

        pi->valid = 0;

        return pi;

}

long jpc_dec_lookahead(jas_stream_t *in)

{

        uint_fast16_t x;

        if (jpc_getuint16(in, &x)) {

                return -1;

        }

        if (jas_stream_ungetc(in, x & 0xff) == EOF ||

          jas_stream_ungetc(in, x >> 8) == EOF) {

                return -1;

        }

        if (x >= JPC_MS_INMIN && x <= JPC_MS_INMAX) {

                return x;

        }

        return 0;

}