/*
 * 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) 1999-2000 Image Power, Inc.
 * Copyright (c) 1999-2000 The University of British Columbia
 * Copyright (c) 2001-2003 Michael David Adams
 * 
 * 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 1.1 2005/05/22 18:33:05 malaterre 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) { \
    fprintf(stderr, "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) { \
    fprintf(stderr, "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) {
          fprintf(stderr, "warning: corrupt code stream\n");
        } else {
          if (cblk->numimsbs < ccp->roishift - band->numbps) {
            fprintf(stderr, "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) {
        fprintf(stderr, "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) {
        fprintf(stderr, "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) {
      fprintf(stderr, "warning: bad segmentation symbol\n");
    }
  }

  return 0;
}