env/opencv-4.8.0/3rdparty/libjasper/jpc_t1dec.c

/*
 * 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 License Version 2.0
 *
 * Copyright (c) 2001-2006 Michael David Adams
 * Copyright (c) 1999-2000 Image Power, Inc.
 * Copyright (c) 1999-2000 The University of British Columbia
 *
 * All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person (the
 * "User") obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, and/or sell copies of the Software, and to permit
 * persons to whom the Software is furnished to do so, subject to the
 * following conditions:
 *
 * 1.  The above copyright notices and this permission notice (which
 * includes the disclaimer below) shall be included in all copies or
 * substantial portions of the Software.
 *
 * 2.  The name of a copyright holder shall not be used to endorse or
 * promote products derived from the Software without specific prior
 * written permission.
 *
 * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS
 * LICENSE.  NO USE OF THE SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER
 * THIS DISCLAIMER.  THE SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS
 * "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.  IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL
 * INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING
 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.  NO ASSURANCES ARE
 * PROVIDED BY THE COPYRIGHT HOLDERS THAT THE SOFTWARE DOES NOT INFRINGE
 * THE PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OF ANY OTHER ENTITY.
 * EACH COPYRIGHT HOLDER DISCLAIMS ANY LIABILITY TO THE USER FOR CLAIMS
 * BROUGHT BY ANY OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL
 * PROPERTY RIGHTS OR OTHERWISE.  AS A CONDITION TO EXERCISING THE RIGHTS
 * GRANTED HEREUNDER, EACH USER HEREBY ASSUMES SOLE RESPONSIBILITY TO SECURE
 * ANY OTHER INTELLECTUAL PROPERTY RIGHTS NEEDED, IF ANY.  THE SOFTWARE
 * IS NOT FAULT-TOLERANT AND IS NOT INTENDED FOR USE IN MISSION-CRITICAL
 * SYSTEMS, SUCH AS THOSE USED IN THE OPERATION OF NUCLEAR FACILITIES,
 * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL
 * SYSTEMS, DIRECT LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH
 * THE FAILURE OF THE SOFTWARE OR SYSTEM COULD LEAD DIRECTLY TO DEATH,
 * PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH
 * RISK ACTIVITIES").  THE COPYRIGHT HOLDERS SPECIFICALLY DISCLAIM ANY
 * EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES.
 *
 * __END_OF_JASPER_LICENSE__
 */

/*
 * Tier 1 Decoder
 *
 * $Id: jpc_t1dec.c,v 1.2 2008-05-26 09:40:52 vp153 Exp $
 */

/******************************************************************************\
* Includes.
\******************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>

#include "jasper/jas_fix.h"
#include "jasper/jas_stream.h"
#include "jasper/jas_math.h"

#include "jpc_bs.h"
#include "jpc_mqdec.h"
#include "jpc_t1dec.h"
#include "jpc_t1cod.h"
#include "jpc_dec.h"

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

static int jpc_dec_decodecblk(jpc_dec_t *dec, jpc_dec_tile_t *tile, jpc_dec_tcomp_t *tcomp, jpc_dec_band_t *band,
  jpc_dec_cblk_t *cblk, int dopartial, int maxlyrs);
static int dec_sigpass(jpc_dec_t *dec, jpc_mqdec_t *mqdec, int bitpos, int orient,
  int vcausalflag, jas_matrix_t *flags, jas_matrix_t *data);
static int dec_rawsigpass(jpc_dec_t *dec, jpc_bitstream_t *in, int bitpos,
  int vcausalflag, jas_matrix_t *flags, jas_matrix_t *data);
static int dec_refpass(jpc_dec_t *dec, jpc_mqdec_t *mqdec, int bitpos, int vcausalflag,
  jas_matrix_t *flags, jas_matrix_t *data);
static int dec_rawrefpass(jpc_dec_t *dec, jpc_bitstream_t *in, int bitpos,
  int vcausalflag, jas_matrix_t *flags, jas_matrix_t *data);
static int dec_clnpass(jpc_dec_t *dec, jpc_mqdec_t *mqdec, int bitpos, int orient,
  int vcausalflag, int segsymflag, jas_matrix_t *flags, jas_matrix_t *data);

#if defined(DEBUG)
static long t1dec_cnt = 0;
#endif

#if !defined(DEBUG)
#define	JPC_T1D_GETBIT(mqdec, v, passtypename, symtypename) \
    ((v) = jpc_mqdec_getbit(mqdec))
#else
#define	JPC_T1D_GETBIT(mqdec, v, passtypename, symtypename) \
{ \
    (v) = jpc_mqdec_getbit(mqdec); \
    if (jas_getdbglevel() >= 100) { \
        jas_eprintf("index = %ld; passtype = %s; symtype = %s; sym = %d\n", t1dec_cnt, passtypename, symtypename, v); \
        ++t1dec_cnt; \
    } \
}
#endif
#define	JPC_T1D_GETBITNOSKEW(mqdec, v, passtypename, symtypename) \
    JPC_T1D_GETBIT(mqdec, v, passtypename, symtypename)

#if !defined(DEBUG)
#define	JPC_T1D_RAWGETBIT(bitstream, v, passtypename, symtypename) \
    ((v) = jpc_bitstream_getbit(bitstream))
#else
#define	JPC_T1D_RAWGETBIT(bitstream, v, passtypename, symtypename) \
{ \
    (v) = jpc_bitstream_getbit(bitstream); \
    if (jas_getdbglevel() >= 100) { \
        jas_eprintf("index = %ld; passtype = %s; symtype = %s; sym = %d\n", t1dec_cnt, passtypename, symtypename, v); \
        ++t1dec_cnt; \
    } \
}
#endif

/******************************************************************************\
* Code.
\******************************************************************************/

int jpc_dec_decodecblks(jpc_dec_t *dec, jpc_dec_tile_t *tile)
{
    jpc_dec_tcomp_t *tcomp;
    int compcnt;
    jpc_dec_rlvl_t *rlvl;
    int rlvlcnt;
    jpc_dec_band_t *band;
    int bandcnt;
    jpc_dec_prc_t *prc;
    int prccnt;
    jpc_dec_cblk_t *cblk;
    int cblkcnt;

    for (compcnt = dec->numcomps, tcomp = tile->tcomps; compcnt > 0;
      --compcnt, ++tcomp) {
        for (rlvlcnt = tcomp->numrlvls, rlvl = tcomp->rlvls;
          rlvlcnt > 0; --rlvlcnt, ++rlvl) {
            if (!rlvl->bands) {
                continue;
            }
            for (bandcnt = rlvl->numbands, band = rlvl->bands;
              bandcnt > 0; --bandcnt, ++band) {
                if (!band->data) {
                    continue;
                }
                for (prccnt = rlvl->numprcs, prc = band->prcs;
                  prccnt > 0; --prccnt, ++prc) {
                    if (!prc->cblks) {
                        continue;
                    }
                    for (cblkcnt = prc->numcblks,
                      cblk = prc->cblks; cblkcnt > 0;
                      --cblkcnt, ++cblk) {
                        if (jpc_dec_decodecblk(dec, tile, tcomp,
                          band, cblk, 1, JPC_MAXLYRS)) {
                            return -1;
                        }
                    }
                }

            }
        }
    }

    return 0;
}

static int jpc_dec_decodecblk(jpc_dec_t *dec, jpc_dec_tile_t *tile, jpc_dec_tcomp_t *tcomp, jpc_dec_band_t *band,
  jpc_dec_cblk_t *cblk, int dopartial, int maxlyrs)
{
    jpc_dec_seg_t *seg;
    int i;
    int bpno;
    int passtype;
    int ret;
    int compno;
    int filldata;
    int fillmask;
    jpc_dec_ccp_t *ccp;

    compno = tcomp - tile->tcomps;

    if (!cblk->flags) {
        /* Note: matrix is assumed to be zeroed */
        if (!(cblk->flags = jas_matrix_create(jas_matrix_numrows(cblk->data) +
          2, jas_matrix_numcols(cblk->data) + 2))) {
            return -1;
        }
    }

    seg = cblk->segs.head;
    while (seg && (seg != cblk->curseg || dopartial) && (maxlyrs < 0 ||
      seg->lyrno < maxlyrs)) {
        assert(seg->numpasses >= seg->maxpasses || dopartial);
        assert(seg->stream);
        jas_stream_rewind(seg->stream);
        jas_stream_setrwcount(seg->stream, 0);
        if (seg->type == JPC_SEG_MQ) {
            if (!cblk->mqdec) {
                if (!(cblk->mqdec = jpc_mqdec_create(JPC_NUMCTXS, 0))) {
                    return -1;
                }
                jpc_mqdec_setctxs(cblk->mqdec, JPC_NUMCTXS, jpc_mqctxs);
            }
            jpc_mqdec_setinput(cblk->mqdec, seg->stream);
            jpc_mqdec_init(cblk->mqdec);
        } else {
            assert(seg->type == JPC_SEG_RAW);
            if (!cblk->nulldec) {
                if (!(cblk->nulldec = jpc_bitstream_sopen(seg->stream, "r"))) {
                    assert(0);
                }
            }
        }


        for (i = 0; i < seg->numpasses; ++i) {
            if (cblk->numimsbs > band->numbps) {
                ccp = &tile->cp->ccps[compno];
                if (ccp->roishift <= 0) {
                    jas_eprintf("warning: corrupt code stream\n");
                } else {
                    if (cblk->numimsbs < ccp->roishift - band->numbps) {
                        jas_eprintf("warning: corrupt code stream\n");
                    }
                }
            }
            bpno = band->roishift + band->numbps - 1 - (cblk->numimsbs +
              (seg->passno + i - cblk->firstpassno + 2) / 3);
if (bpno < 0) {
    goto premature_exit;
}
#if 1
            passtype = (seg->passno + i + 2) % 3;
#else
            passtype = JPC_PASSTYPE(seg->passno + i + 2);
#endif
            assert(bpno >= 0 && bpno < 31);
            switch (passtype) {
            case JPC_SIGPASS:
                ret = (seg->type == JPC_SEG_MQ) ? dec_sigpass(dec,
                  cblk->mqdec, bpno, band->orient,
                  (tile->cp->ccps[compno].cblkctx & JPC_COX_VSC) != 0,
                  cblk->flags, cblk->data) :
                  dec_rawsigpass(dec, cblk->nulldec, bpno,
                  (tile->cp->ccps[compno].cblkctx & JPC_COX_VSC) != 0,
                  cblk->flags, cblk->data);
                break;
            case JPC_REFPASS:
                ret = (seg->type == JPC_SEG_MQ) ?
                  dec_refpass(dec, cblk->mqdec, bpno,
                  (tile->cp->ccps[compno].cblkctx & JPC_COX_VSC) != 0,
                  cblk->flags, cblk->data) :
                  dec_rawrefpass(dec, cblk->nulldec, bpno,
                  (tile->cp->ccps[compno].cblkctx & JPC_COX_VSC) != 0,
                  cblk->flags, cblk->data);
                break;
            case JPC_CLNPASS:
                assert(seg->type == JPC_SEG_MQ);
                ret = dec_clnpass(dec, cblk->mqdec, bpno,
                  band->orient, (tile->cp->ccps[compno].cblkctx &
                  JPC_COX_VSC) != 0, (tile->cp->ccps[compno].cblkctx &
                  JPC_COX_SEGSYM) != 0, cblk->flags,
                  cblk->data);
                break;
            default:
                ret = -1;
                break;
            }
            /* Do we need to reset after each coding pass? */
            if (tile->cp->ccps[compno].cblkctx & JPC_COX_RESET) {
                jpc_mqdec_setctxs(cblk->mqdec, JPC_NUMCTXS, jpc_mqctxs);
            }

            if (ret) {
                jas_eprintf("coding pass failed passtype=%d segtype=%d\n", passtype, seg->type);
                return -1;
            }

        }

        if (seg->type == JPC_SEG_MQ) {
/* Note: dont destroy mq decoder because context info will be lost */
        } else {
            assert(seg->type == JPC_SEG_RAW);
            if (tile->cp->ccps[compno].cblkctx & JPC_COX_PTERM) {
                fillmask = 0x7f;
                filldata = 0x2a;
            } else {
                fillmask = 0;
                filldata = 0;
            }
            if ((ret = jpc_bitstream_inalign(cblk->nulldec, fillmask,
              filldata)) < 0) {
                return -1;
            } else if (ret > 0) {
                jas_eprintf("warning: bad termination pattern detected\n");
            }
            jpc_bitstream_close(cblk->nulldec);
            cblk->nulldec = 0;
        }

        cblk->curseg = seg->next;
        jpc_seglist_remove(&cblk->segs, seg);
        jpc_seg_destroy(seg);
        seg = cblk->curseg;
    }

    assert(dopartial ? (!cblk->curseg) : 1);

premature_exit:
    return 0;
}

/******************************************************************************\
* Code for significance pass.
\******************************************************************************/

#define	jpc_sigpass_step(fp, frowstep, dp, bitpos, oneplushalf, orient, mqdec, vcausalflag) \
{ \
    int f; \
    int v; \
    f = *(fp); \
    if ((f & JPC_OTHSIGMSK) && !(f & (JPC_SIG | JPC_VISIT))) { \
        jpc_mqdec_setcurctx((mqdec), JPC_GETZCCTXNO(f, (orient))); \
        JPC_T1D_GETBIT((mqdec), v, "SIG", "ZC"); \
        if (v) { \
            jpc_mqdec_setcurctx((mqdec), JPC_GETSCCTXNO(f)); \
            JPC_T1D_GETBIT((mqdec), v, "SIG", "SC"); \
            v ^= JPC_GETSPB(f); \
            JPC_UPDATEFLAGS4((fp), (frowstep), v, (vcausalflag)); \
            *(fp) |= JPC_SIG; \
            *(dp) = (v) ? (-(oneplushalf)) : (oneplushalf); \
        } \
        *(fp) |= JPC_VISIT; \
    } \
}

static int dec_sigpass(jpc_dec_t *dec, register jpc_mqdec_t *mqdec, int bitpos, int orient,
  int vcausalflag, jas_matrix_t *flags, jas_matrix_t *data)
{
    int i;
    int j;
    int one;
    int half;
    int oneplushalf;
    int vscanlen;
    int width;
    int height;
    jpc_fix_t *fp;
    int frowstep;
    int fstripestep;
    jpc_fix_t *fstripestart;
    jpc_fix_t *fvscanstart;
    jpc_fix_t *dp;
    int drowstep;
    int dstripestep;
    jpc_fix_t *dstripestart;
    jpc_fix_t *dvscanstart;
    int k;

    /* Avoid compiler warning about unused parameters. */
    dec = 0;

    width = jas_matrix_numcols(data);
    height = jas_matrix_numrows(data);
    frowstep = jas_matrix_rowstep(flags);
    drowstep = jas_matrix_rowstep(data);
    fstripestep = frowstep << 2;
    dstripestep = drowstep << 2;

    one = 1 << bitpos;
    half = one >> 1;
    oneplushalf = one | half;

    fstripestart = jas_matrix_getref(flags, 1, 1);
    dstripestart = jas_matrix_getref(data, 0, 0);
    for (i = height; i > 0; i -= 4, fstripestart += fstripestep,
      dstripestart += dstripestep) {
        fvscanstart = fstripestart;
        dvscanstart = dstripestart;
        vscanlen = JAS_MIN(i, 4);
        for (j = width; j > 0; --j, ++fvscanstart, ++dvscanstart) {
            fp = fvscanstart;
            dp = dvscanstart;
            k = vscanlen;

            /* Process first sample in vertical scan. */
            jpc_sigpass_step(fp, frowstep, dp, bitpos, oneplushalf,
              orient, mqdec, vcausalflag);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process second sample in vertical scan. */
            jpc_sigpass_step(fp, frowstep, dp, bitpos, oneplushalf,
              orient, mqdec, 0);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process third sample in vertical scan. */
            jpc_sigpass_step(fp, frowstep, dp, bitpos, oneplushalf,
              orient, mqdec, 0);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process fourth sample in vertical scan. */
            jpc_sigpass_step(fp, frowstep, dp, bitpos, oneplushalf,
              orient, mqdec, 0);
        }
    }
    return 0;
}

#define	jpc_rawsigpass_step(fp, frowstep, dp, oneplushalf, in, vcausalflag) \
{ \
    jpc_fix_t f = *(fp); \
    jpc_fix_t v; \
    if ((f & JPC_OTHSIGMSK) && !(f & (JPC_SIG | JPC_VISIT))) { \
        JPC_T1D_RAWGETBIT(in, v, "SIG", "ZC"); \
        if (v < 0) { \
            return -1; \
        } \
        if (v) { \
            JPC_T1D_RAWGETBIT(in, v, "SIG", "SC"); \
            if (v < 0) { \
                return -1; \
            } \
            JPC_UPDATEFLAGS4((fp), (frowstep), v, (vcausalflag)); \
            *(fp) |= JPC_SIG; \
            *(dp) = v ? (-oneplushalf) : (oneplushalf); \
        } \
        *(fp) |= JPC_VISIT; \
    } \
}

static int dec_rawsigpass(jpc_dec_t *dec, jpc_bitstream_t *in, int bitpos, int vcausalflag,
  jas_matrix_t *flags, jas_matrix_t *data)
{
    int i;
    int j;
    int k;
    int one;
    int half;
    int oneplushalf;
    int vscanlen;
    int width;
    int height;
    jpc_fix_t *fp;
    int frowstep;
    int fstripestep;
    jpc_fix_t *fstripestart;
    jpc_fix_t *fvscanstart;
    jpc_fix_t *dp;
    int drowstep;
    int dstripestep;
    jpc_fix_t *dstripestart;
    jpc_fix_t *dvscanstart;

    /* Avoid compiler warning about unused parameters. */
    dec = 0;

    width = jas_matrix_numcols(data);
    height = jas_matrix_numrows(data);
    frowstep = jas_matrix_rowstep(flags);
    drowstep = jas_matrix_rowstep(data);
    fstripestep = frowstep << 2;
    dstripestep = drowstep << 2;

    one = 1 << bitpos;
    half = one >> 1;
    oneplushalf = one | half;

    fstripestart = jas_matrix_getref(flags, 1, 1);
    dstripestart = jas_matrix_getref(data, 0, 0);
    for (i = height; i > 0; i -= 4, fstripestart += fstripestep,
      dstripestart += dstripestep) {
        fvscanstart = fstripestart;
        dvscanstart = dstripestart;
        vscanlen = JAS_MIN(i, 4);
        for (j = width; j > 0; --j, ++fvscanstart, ++dvscanstart) {
            fp = fvscanstart;
            dp = dvscanstart;
            k = vscanlen;

            /* Process first sample in vertical scan. */
            jpc_rawsigpass_step(fp, frowstep, dp, oneplushalf,
              in, vcausalflag);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process second sample in vertical scan. */
            jpc_rawsigpass_step(fp, frowstep, dp, oneplushalf,
              in, 0);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process third sample in vertical scan. */
            jpc_rawsigpass_step(fp, frowstep, dp, oneplushalf,
              in, 0);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process fourth sample in vertical scan. */
            jpc_rawsigpass_step(fp, frowstep, dp, oneplushalf,
              in, 0);

        }
    }
    return 0;
}

/******************************************************************************\
* Code for refinement pass.
\******************************************************************************/

#define	jpc_refpass_step(fp, dp, poshalf, neghalf, mqdec, vcausalflag) \
{ \
    int v; \
    int t; \
    if (((*(fp)) & (JPC_SIG | JPC_VISIT)) == JPC_SIG) { \
        jpc_mqdec_setcurctx((mqdec), JPC_GETMAGCTXNO(*(fp))); \
        JPC_T1D_GETBITNOSKEW((mqdec), v, "REF", "MR"); \
        t = (v ? (poshalf) : (neghalf)); \
        *(dp) += (*(dp) < 0) ? (-t) : t; \
        *(fp) |= JPC_REFINE; \
    } \
}

static int dec_refpass(jpc_dec_t *dec, register jpc_mqdec_t *mqdec, int bitpos,
  int vcausalflag, jas_matrix_t *flags, jas_matrix_t *data)
{
    int i;
    int j;
    int vscanlen;
    int width;
    int height;
    int one;
    int poshalf;
    int neghalf;
    jpc_fix_t *fp;
    int frowstep;
    int fstripestep;
    jpc_fix_t *fstripestart;
    jpc_fix_t *fvscanstart;
    jpc_fix_t *dp;
    int drowstep;
    int dstripestep;
    jpc_fix_t *dstripestart;
    jpc_fix_t *dvscanstart;
    int k;

    /* Avoid compiler warning about unused parameters. */
    dec = 0;
    vcausalflag = 0;

    width = jas_matrix_numcols(data);
    height = jas_matrix_numrows(data);
    frowstep = jas_matrix_rowstep(flags);
    drowstep = jas_matrix_rowstep(data);
    fstripestep = frowstep << 2;
    dstripestep = drowstep << 2;

    one = 1 << bitpos;
    poshalf = one >> 1;
    neghalf = (bitpos > 0) ? (-poshalf) : (-1);

    fstripestart = jas_matrix_getref(flags, 1, 1);
    dstripestart = jas_matrix_getref(data, 0, 0);
    for (i = height; i > 0; i -= 4, fstripestart += fstripestep,
      dstripestart += dstripestep) {
        fvscanstart = fstripestart;
        dvscanstart = dstripestart;
        vscanlen = JAS_MIN(i, 4);
        for (j = width; j > 0; --j, ++fvscanstart, ++dvscanstart) {
            fp = fvscanstart;
            dp = dvscanstart;
            k = vscanlen;

            /* Process first sample in vertical scan. */
            jpc_refpass_step(fp, dp, poshalf, neghalf, mqdec,
              vcausalflag);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process second sample in vertical scan. */
            jpc_refpass_step(fp, dp, poshalf, neghalf, mqdec, 0);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process third sample in vertical scan. */
            jpc_refpass_step(fp, dp, poshalf, neghalf, mqdec, 0);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process fourth sample in vertical scan. */
            jpc_refpass_step(fp, dp, poshalf, neghalf, mqdec, 0);
        }
    }

    return 0;
}

#define	jpc_rawrefpass_step(fp, dp, poshalf, neghalf, in, vcausalflag) \
{ \
    jpc_fix_t v; \
    jpc_fix_t t; \
    if (((*(fp)) & (JPC_SIG | JPC_VISIT)) == JPC_SIG) { \
        JPC_T1D_RAWGETBIT(in, v, "REF", "MAGREF"); \
        if (v < 0) { \
            return -1; \
        } \
        t = (v ? poshalf : neghalf); \
        *(dp) += (*(dp) < 0) ? (-t) : t; \
        *(fp) |= JPC_REFINE; \
    } \
}

static int dec_rawrefpass(jpc_dec_t *dec, jpc_bitstream_t *in, int bitpos, int vcausalflag,
  jas_matrix_t *flags, jas_matrix_t *data)
{
    int i;
    int j;
    int k;
    int vscanlen;
    int width;
    int height;
    int one;
    int poshalf;
    int neghalf;
    jpc_fix_t *fp;
    int frowstep;
    int fstripestep;
    jpc_fix_t *fstripestart;
    jpc_fix_t *fvscanstart;
    jpc_fix_t *dp;
    int drowstep;
    int dstripestep;
    jpc_fix_t *dstripestart;
    jpc_fix_t *dvscanstart;

    /* Avoid compiler warning about unused parameters. */
    dec = 0;
    vcausalflag = 0;

    width = jas_matrix_numcols(data);
    height = jas_matrix_numrows(data);
    frowstep = jas_matrix_rowstep(flags);
    drowstep = jas_matrix_rowstep(data);
    fstripestep = frowstep << 2;
    dstripestep = drowstep << 2;

    one = 1 << bitpos;
    poshalf = one >> 1;
    neghalf = (bitpos > 0) ? (-poshalf) : (-1);

    fstripestart = jas_matrix_getref(flags, 1, 1);
    dstripestart = jas_matrix_getref(data, 0, 0);
    for (i = height; i > 0; i -= 4, fstripestart += fstripestep,
      dstripestart += dstripestep) {
        fvscanstart = fstripestart;
        dvscanstart = dstripestart;
        vscanlen = JAS_MIN(i, 4);
        for (j = width; j > 0; --j, ++fvscanstart, ++dvscanstart) {
            fp = fvscanstart;
            dp = dvscanstart;
            k = vscanlen;

            /* Process first sample in vertical scan. */
            jpc_rawrefpass_step(fp, dp, poshalf, neghalf, in,
              vcausalflag);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process second sample in vertical scan. */
            jpc_rawrefpass_step(fp, dp, poshalf, neghalf, in, 0);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process third sample in vertical scan. */
            jpc_rawrefpass_step(fp, dp, poshalf, neghalf, in, 0);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process fourth sample in vertical scan. */
            jpc_rawrefpass_step(fp, dp, poshalf, neghalf, in, 0);
        }
    }
    return 0;
}

/******************************************************************************\
* Code for cleanup pass.
\******************************************************************************/

#define	jpc_clnpass_step(f, fp, frowstep, dp, oneplushalf, orient, mqdec, flabel, plabel, vcausalflag) \
{ \
    int v; \
flabel \
    if (!((f) & (JPC_SIG | JPC_VISIT))) { \
        jpc_mqdec_setcurctx((mqdec), JPC_GETZCCTXNO((f), (orient))); \
        JPC_T1D_GETBIT((mqdec), v, "CLN", "ZC"); \
        if (v) { \
plabel \
            /* Coefficient is significant. */ \
            jpc_mqdec_setcurctx((mqdec), JPC_GETSCCTXNO(f)); \
            JPC_T1D_GETBIT((mqdec), v, "CLN", "SC"); \
            v ^= JPC_GETSPB(f); \
            *(dp) = (v) ? (-(oneplushalf)) : (oneplushalf); \
            JPC_UPDATEFLAGS4((fp), (frowstep), v, (vcausalflag)); \
            *(fp) |= JPC_SIG; \
        } \
    } \
    /* XXX - Is this correct?  Can aggregation cause some VISIT bits not to be reset?  Check. */ \
    *(fp) &= ~JPC_VISIT; \
}

static int dec_clnpass(jpc_dec_t *dec, register jpc_mqdec_t *mqdec, int bitpos, int orient,
  int vcausalflag, int segsymflag, jas_matrix_t *flags, jas_matrix_t *data)
{
    int i;
    int j;
    int k;
    int vscanlen;
    int v;
    int half;
    int runlen;
    int f;
    int width;
    int height;
    int one;
    int oneplushalf;

    jpc_fix_t *fp;
    int frowstep;
    int fstripestep;
    jpc_fix_t *fstripestart;
    jpc_fix_t *fvscanstart;

    jpc_fix_t *dp;
    int drowstep;
    int dstripestep;
    jpc_fix_t *dstripestart;
    jpc_fix_t *dvscanstart;

    /* Avoid compiler warning about unused parameters. */
    dec = 0;

    one = 1 << bitpos;
    half = one >> 1;
    oneplushalf = one | half;

    width = jas_matrix_numcols(data);
    height = jas_matrix_numrows(data);

    frowstep = jas_matrix_rowstep(flags);
    drowstep = jas_matrix_rowstep(data);
    fstripestep = frowstep << 2;
    dstripestep = drowstep << 2;

    fstripestart = jas_matrix_getref(flags, 1, 1);
    dstripestart = jas_matrix_getref(data, 0, 0);
    for (i = 0; i < height; i += 4, fstripestart += fstripestep,
      dstripestart += dstripestep) {
        fvscanstart = fstripestart;
        dvscanstart = dstripestart;
        vscanlen = JAS_MIN(4, height - i);
        for (j = width; j > 0; --j, ++fvscanstart, ++dvscanstart) {
            fp = fvscanstart;
            if (vscanlen >= 4 && (!((*fp) & (JPC_SIG | JPC_VISIT |
              JPC_OTHSIGMSK))) && (fp += frowstep, !((*fp) & (JPC_SIG |
              JPC_VISIT | JPC_OTHSIGMSK))) && (fp += frowstep, !((*fp) &
              (JPC_SIG | JPC_VISIT | JPC_OTHSIGMSK))) && (fp += frowstep,
              !((*fp) & (JPC_SIG | JPC_VISIT | JPC_OTHSIGMSK)))) {

                jpc_mqdec_setcurctx(mqdec, JPC_AGGCTXNO);
                JPC_T1D_GETBIT(mqdec, v, "CLN", "AGG");
                if (!v) {
                    continue;
                }
                jpc_mqdec_setcurctx(mqdec, JPC_UCTXNO);
                JPC_T1D_GETBITNOSKEW(mqdec, v, "CLN", "RL");
                runlen = v;
                JPC_T1D_GETBITNOSKEW(mqdec, v, "CLN", "RL");
                runlen = (runlen << 1) | v;
                f = *(fp = fvscanstart + frowstep * runlen);
                dp = dvscanstart + drowstep * runlen;
                k = vscanlen - runlen;
                switch (runlen) {
                case 0:
                    goto clnpass_partial0;
                    break;
                case 1:
                    goto clnpass_partial1;
                    break;
                case 2:
                    goto clnpass_partial2;
                    break;
                case 3:
                    goto clnpass_partial3;
                    break;
                }
            } else {
                f = *(fp = fvscanstart);
                dp = dvscanstart;
                k = vscanlen;
                goto clnpass_full0;
            }

            /* Process first sample in vertical scan. */
            jpc_clnpass_step(f, fp, frowstep, dp, oneplushalf, orient,
              mqdec, clnpass_full0:, clnpass_partial0:,
              vcausalflag);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process second sample in vertical scan. */
            f = *fp;
            jpc_clnpass_step(f, fp, frowstep, dp, oneplushalf, orient,
                mqdec, ;, clnpass_partial1:, 0);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process third sample in vertical scan. */
            f = *fp;
            jpc_clnpass_step(f, fp, frowstep, dp, oneplushalf, orient,
                mqdec, ;, clnpass_partial2:, 0);
            if (--k <= 0) {
                continue;
            }
            fp += frowstep;
            dp += drowstep;

            /* Process fourth sample in vertical scan. */
            f = *fp;
            jpc_clnpass_step(f, fp, frowstep, dp, oneplushalf, orient,
                mqdec, ;, clnpass_partial3:, 0);
        }
    }

    if (segsymflag) {
        int segsymval;
        segsymval = 0;
        jpc_mqdec_setcurctx(mqdec, JPC_UCTXNO);
        JPC_T1D_GETBITNOSKEW(mqdec, v, "CLN", "SEGSYM");
        segsymval = (segsymval << 1) | (v & 1);
        JPC_T1D_GETBITNOSKEW(mqdec, v, "CLN", "SEGSYM");
        segsymval = (segsymval << 1) | (v & 1);
        JPC_T1D_GETBITNOSKEW(mqdec, v, "CLN", "SEGSYM");
        segsymval = (segsymval << 1) | (v & 1);
        JPC_T1D_GETBITNOSKEW(mqdec, v, "CLN", "SEGSYM");
        segsymval = (segsymval << 1) | (v & 1);
        if (segsymval != 0xa) {
            jas_eprintf("warning: bad segmentation symbol\n");
        }
    }

    return 0;
}