jpc_dec.c

用C语言实现的JPEG编码

}

	for (pchgno = 0; pchgno < jpc_pchglist_numpchgs(tile->cp->pchglist);
	  ++pchgno) {
		pchg = jpc_pchg_copy(jpc_pchglist_get(tile->cp->pchglist, pchgno));
		assert(pchg);
		jpc_pi_addpchg(tile->pi, pchg);
	}
	jpc_pi_init(tile->pi);

	return 0;
}

static int jpc_dec_tilefini(jpc_dec_t *dec, jpc_dec_tile_t *tile)
{
	jpc_dec_tcomp_t *tcomp;
	int compno;
	int bandno;
	int rlvlno;
	jpc_dec_band_t *band;
	jpc_dec_rlvl_t *rlvl;
	int prcno;
	jpc_dec_prc_t *prc;
	jpc_dec_seg_t *seg;
	jpc_dec_cblk_t *cblk;
	int cblkno;

if (tile->tcomps) {

	for (compno = 0, tcomp = tile->tcomps; compno < dec->numcomps;
	  ++compno, ++tcomp) {
		for (rlvlno = 0, rlvl = tcomp->rlvls; rlvlno < tcomp->numrlvls;
		  ++rlvlno, ++rlvl) {
if (!rlvl->bands) {
	continue;
}
			for (bandno = 0, band = rlvl->bands; bandno < rlvl->numbands; ++bandno, ++band) {
if (band->prcs) {
				for (prcno = 0, prc = band->prcs; prcno <
				  rlvl->numprcs; ++prcno, ++prc) {
if (!prc->cblks) {
	continue;
}
					for (cblkno = 0, cblk = prc->cblks; cblkno < prc->numcblks; ++cblkno, ++cblk) {

	while (cblk->segs.head) {
		seg = cblk->segs.head;
		jpc_seglist_remove(&cblk->segs, seg);
		jpc_seg_destroy(seg);
	}
	jas_matrix_destroy(cblk->data);
	if (cblk->mqdec) {
		jpc_mqdec_destroy(cblk->mqdec);
	}
	if (cblk->nulldec) {
		jpc_bitstream_close(cblk->nulldec);
	}
	if (cblk->flags) {
		jas_matrix_destroy(cblk->flags);
	}
					}
					if (prc->incltagtree) {
						jpc_tagtree_destroy(prc->incltagtree);
					}
					if (prc->numimsbstagtree) {
						jpc_tagtree_destroy(prc->numimsbstagtree);
					}
					if (prc->cblks) {
						jas_free(prc->cblks);
					}
				}
}
				if (band->data) {
					jas_matrix_destroy(band->data);
				}
				if (band->prcs) {
					jas_free(band->prcs);
				}
			}
			if (rlvl->bands) {
				jas_free(rlvl->bands);
			}
		}
		if (tcomp->rlvls) {
			jas_free(tcomp->rlvls);
		}
		if (tcomp->data) {
			jas_matrix_destroy(tcomp->data);
		}
		if (tcomp->tsfb) {
			jpc_tsfb_destroy(tcomp->tsfb);
		}
	}
}
	if (tile->cp) {
		jpc_dec_cp_destroy(tile->cp);
		tile->cp = 0;
	}
	if (tile->tcomps) {
		jas_free(tile->tcomps);
		tile->tcomps = 0;
	}
	if (tile->pi) {
		jpc_pi_destroy(tile->pi);
		tile->pi = 0;
	}
	if (tile->pkthdrstream) {
		jas_stream_close(tile->pkthdrstream);
		tile->pkthdrstream = 0;
	}
	if (tile->pptstab) {
		jpc_ppxstab_destroy(tile->pptstab);
		tile->pptstab = 0;
	}

	tile->state = JPC_TILE_DONE;

	return 0;
}

static int jpc_dec_tiledecode(jpc_dec_t *dec, jpc_dec_tile_t *tile)
{
	int i;
	int j;
	jpc_dec_tcomp_t *tcomp;
	jpc_dec_rlvl_t *rlvl;
	jpc_dec_band_t *band;
	int compno;
	int rlvlno;
	int bandno;
	int adjust;
	int v;
	jpc_dec_ccp_t *ccp;
	jpc_dec_cmpt_t *cmpt;

	if (jpc_dec_decodecblks(dec, tile)) {
		fprintf(stderr, "jpc_dec_decodecblks failed\n");
		return -1;
	}

	/* Perform dequantization. */
	for (compno = 0, tcomp = tile->tcomps; compno < dec->numcomps;
	  ++compno, ++tcomp) {
		ccp = &tile->cp->ccps[compno];
		for (rlvlno = 0, rlvl = tcomp->rlvls; rlvlno < tcomp->numrlvls;
		  ++rlvlno, ++rlvl) {
			if (!rlvl->bands) {
				continue;
			}
			for (bandno = 0, band = rlvl->bands;
			  bandno < rlvl->numbands; ++bandno, ++band) {
				if (!band->data) {
					continue;
				}
				jpc_undo_roi(band->data, band->roishift, ccp->roishift -
				  band->roishift, band->numbps);
				if (tile->realmode) {
					jas_matrix_asl(band->data, JPC_FIX_FRACBITS);
					jpc_dequantize(band->data, band->absstepsize);
				}

			}
		}
	}

	/* Apply an inverse wavelet transform if necessary. */
	for (compno = 0, tcomp = tile->tcomps; compno < dec->numcomps;
	  ++compno, ++tcomp) {
		ccp = &tile->cp->ccps[compno];
		jpc_tsfb_synthesize(tcomp->tsfb, ((ccp->qmfbid ==
		  JPC_COX_RFT) ? JPC_TSFB_RITIMODE : 0), tcomp->data);
	}


	/* Apply an inverse intercomponent transform if necessary. */
	switch (tile->cp->mctid) {
	case JPC_MCT_RCT:
		assert(dec->numcomps == 3);
		jpc_irct(tile->tcomps[0].data, tile->tcomps[1].data,
		  tile->tcomps[2].data);
		break;
	case JPC_MCT_ICT:
		assert(dec->numcomps == 3);
		jpc_iict(tile->tcomps[0].data, tile->tcomps[1].data,
		  tile->tcomps[2].data);
		break;
	}

	/* Perform rounding and convert to integer values. */
	if (tile->realmode) {
		for (compno = 0, tcomp = tile->tcomps; compno < dec->numcomps;
		  ++compno, ++tcomp) {
			for (i = 0; i < jas_matrix_numrows(tcomp->data); ++i) {
				for (j = 0; j < jas_matrix_numcols(tcomp->data); ++j) {
					v = jas_matrix_get(tcomp->data, i, j);
					v = jpc_fix_round(v);
					jas_matrix_set(tcomp->data, i, j, jpc_fixtoint(v));
				}
			}
		}
	}

	/* Perform level shift. */
	for (compno = 0, tcomp = tile->tcomps, cmpt = dec->cmpts; compno <
	  dec->numcomps; ++compno, ++tcomp, ++cmpt) {
		adjust = cmpt->sgnd ? 0 : (1 << (cmpt->prec - 1));
		for (i = 0; i < jas_matrix_numrows(tcomp->data); ++i) {
			for (j = 0; j < jas_matrix_numcols(tcomp->data); ++j) {
				*jas_matrix_getref(tcomp->data, i, j) += adjust;
			}
		}
	}

	/* Perform clipping. */
	for (compno = 0, tcomp = tile->tcomps, cmpt = dec->cmpts; compno <
	  dec->numcomps; ++compno, ++tcomp, ++cmpt) {
		jpc_fix_t mn;
		jpc_fix_t mx;
		mn = cmpt->sgnd ? (-(1 << (cmpt->prec - 1))) : (0);
		mx = cmpt->sgnd ? ((1 << (cmpt->prec - 1)) - 1) : ((1 <<
		  cmpt->prec) - 1);
		jas_matrix_clip(tcomp->data, mn, mx);
	}

	/* XXX need to free tsfb struct */

	/* Write the data for each component of the image. */
	for (compno = 0, tcomp = tile->tcomps, cmpt = dec->cmpts; compno <
	  dec->numcomps; ++compno, ++tcomp, ++cmpt) {
		if (jas_image_writecmpt(dec->image, compno, tcomp->xstart -
		  JPC_CEILDIV(dec->xstart, cmpt->hstep), tcomp->ystart -
		  JPC_CEILDIV(dec->ystart, cmpt->vstep), jas_matrix_numcols(
		  tcomp->data), jas_matrix_numrows(tcomp->data), tcomp->data)) {
			fprintf(stderr, "write component failed\n");
			return -4;
		}
	}

	return 0;
}

static int jpc_dec_process_eoc(jpc_dec_t *dec, jpc_ms_t *ms)
{
	int tileno;
	jpc_dec_tile_t *tile;

	/* Eliminate compiler warnings about unused variables. */
	ms = 0;

	for (tileno = 0, tile = dec->tiles; tileno < dec->numtiles; ++tileno,
	  ++tile) {
		if (tile->state == JPC_TILE_ACTIVE) {
			if (jpc_dec_tiledecode(dec, tile)) {
				return -1;
			}
		}
		jpc_dec_tilefini(dec, tile);
	}

	/* We are done processing the code stream. */
	dec->state = JPC_MT;

	return 1;
}

static int jpc_dec_process_siz(jpc_dec_t *dec, jpc_ms_t *ms)
{
	jpc_siz_t *siz = &ms->parms.siz;
	int compno;
	int tileno;
	jpc_dec_tile_t *tile;
	jpc_dec_tcomp_t *tcomp;
	int htileno;
	int vtileno;
	jpc_dec_cmpt_t *cmpt;

	dec->xstart = siz->xoff;
	dec->ystart = siz->yoff;
	dec->xend = siz->width;
	dec->yend = siz->height;
	dec->tilewidth = siz->tilewidth;
	dec->tileheight = siz->tileheight;
	dec->tilexoff = siz->tilexoff;
	dec->tileyoff = siz->tileyoff;
	dec->numcomps = siz->numcomps;
	if (!(dec->cp = jpc_dec_cp_create(dec->numcomps))) {
		return -1;
	}

	if (!(dec->cmpts = jas_malloc(dec->numcomps * sizeof(jpc_dec_cmpt_t)))) {
		return -1;
	}

	for (compno = 0, cmpt = dec->cmpts; compno < dec->numcomps; ++compno,
	  ++cmpt) {
		cmpt->prec = siz->comps[compno].prec;
		cmpt->sgnd = siz->comps[compno].sgnd;
		cmpt->hstep = siz->comps[compno].hsamp;
		cmpt->vstep = siz->comps[compno].vsamp;
		cmpt->width = JPC_CEILDIV(dec->xend, cmpt->hstep) -
		  JPC_CEILDIV(dec->xstart, cmpt->hstep);
		cmpt->height = JPC_CEILDIV(dec->yend, cmpt->vstep) -
		  JPC_CEILDIV(dec->ystart, cmpt->vstep);
		cmpt->hsubstep = 0;
		cmpt->vsubstep = 0;
	}

	dec->image = 0;

	dec->numhtiles = JPC_CEILDIV(dec->xend - dec->tilexoff, dec->tilewidth);
	dec->numvtiles = JPC_CEILDIV(dec->yend - dec->tileyoff, dec->tileheight);
	dec->numtiles = dec->numhtiles * dec->numvtiles;
	if (!(dec->tiles = jas_malloc(dec->numtiles * sizeof(jpc_dec_tile_t)))) {
		return -1;
	}

	for (tileno = 0, tile = dec->tiles; tileno < dec->numtiles; ++tileno,
	  ++tile) {
		htileno = tileno % dec->numhtiles;
		vtileno = tileno / dec->numhtiles;
		tile->realmode = 0;
		tile->state = JPC_TILE_INIT;
		tile->xstart = JAS_MAX(dec->tilexoff + htileno * dec->tilewidth,
		  dec->xstart);
		tile->ystart = JAS_MAX(dec->tileyoff + vtileno * dec->tileheight,
		  dec->ystart);
		tile->xend = JAS_MIN(dec->tilexoff + (htileno + 1) *
		  dec->tilewidth, dec->xend);
		tile->yend = JAS_MIN(dec->tileyoff + (vtileno + 1) *
		  dec->tileheight, dec->yend);
		tile->numparts = 0;
		tile->partno = 0;
		tile->pkthdrstream = 0;
		tile->pkthdrstreampos = 0;
		tile->pptstab = 0;
		tile->cp = 0;
		if (!(tile->tcomps = jas_malloc(dec->numcomps *
		  sizeof(jpc_dec_tcomp_t)))) {
			return -1;
		}
		for (compno = 0, cmpt = dec->cmpts, tcomp = tile->tcomps;
		  compno < dec->numcomps; ++compno, ++cmpt, ++tcomp) {
			tcomp->rlvls = 0;
			tcomp->data = 0;
			tcomp->xstart = JPC_CEILDIV(tile->xstart, cmpt->hstep);
			tcomp->ystart = JPC_CEILDIV(tile->ystart, cmpt->vstep);
			tcomp->xend = JPC_CEILDIV(tile->xend, cmpt->hstep);
			tcomp->yend = JPC_CEILDIV(tile->yend, cmpt->vstep);
			tcomp->tsfb = 0;
		}
	}

	dec->pkthdrstreams = 0;

	/* We should expect to encounter other main header marker segments
	  or an SOT marker segment next. */
	dec->state = JPC_MH;

	return 0;
}

static int jpc_dec_process_cod(jpc_dec_t *dec, jpc_ms_t *ms)
{
	jpc_cod_t *cod = &ms->parms.cod;
	jpc_dec_tile_t *tile;

	switch (dec->state) {
	case JPC_MH:
		jpc_dec_cp_setfromcod(dec->cp, cod);
		break;
	case JPC_TPH:
		if (!(tile = dec->curtile)) {
			return -1;
		}
		if (tile->partno != 0) {
			return -1;
		}
		jpc_dec_cp_setfromcod(tile->cp, cod);
		break;
	}
	return 0;
}

static int jpc_dec_process_coc(jpc_dec_t *dec, jpc_ms_t *ms)
{
	jpc_coc_t *coc = &ms->parms.coc;
	jpc_dec_tile_t *tile;

	if (JAS_CAST(int, coc->compno) > dec->numcomps) {
		fprintf(stderr,
		  "invalid component number in COC marker segment\n");
		return -1;
	}
	switch (dec->state) {
	case JPC_MH:
		jpc_dec_cp_setfromcoc(dec->cp, coc);
		break;
	case JPC_TPH:
		if (!(tile = dec->curtile)) {
			return -1;
		}
		if (tile->partno > 0) {
			return -1;
		}
		jpc_dec_cp_setfromcoc(tile->cp, coc);
		break;
	}
	return 0;
}

static int jpc_dec_process_rgn(jpc_dec_t *dec, jpc_ms_t *ms)
{
	jpc_rgn_t *rgn = &ms->parms.rgn;
	jpc_dec_tile_t *tile;

	if (JAS_CAST(int, rgn->compno) > dec->numcomps) {
		fprintf(stderr,
		  "invalid component number in RGN marker segment\n");
		return -1;
	}
	switch (dec->state) {
	case JPC_MH:
		jpc_dec_cp_setfromrgn(dec->cp, rgn);
		break;
	case JPC_TPH:
		if (!(tile = dec->curtile)) {
			return -1;
		}
		if (tile->partno > 0) {
			return -1;
		}
		jpc_dec_cp_setfromrgn(tile->cp, rgn);
		break;
	}

	return 0;
}

static int jpc_dec_process_qcd(jpc_dec_t *dec, jpc_ms_t *ms)
{
	jpc_qcd_t *qcd = &ms->parms.qcd;
	jpc_dec_tile_t *tile;

	switch (dec->state) {
	case JPC_MH:
		jpc_dec_cp_setfromqcd(dec->cp, qcd);
		break;
	case JPC_TPH:
		if (!(tile = dec->curtile)) {
			return -1;
		}
		if (tile->partno > 0) {
			return -1;
		}
		jpc_dec_cp_setfromqcd(tile->cp, qcd);
		break;
	}
	return 0;
}

static int jpc_dec_process_qcc(jpc_dec_t *dec, jpc_ms_t *ms)
{
	jpc_qcc_t *qcc = &ms->parms.qcc;
	jpc_dec_tile_t *tile;

	if (JAS_CAST(int, qcc->compno) > dec->numcomps) {
		fprintf(stderr,
		  "invalid component number in QCC marker segment\n");
		return -1;
	}
	switch (dec->state) {
	case JPC_MH:
		jpc_dec_cp_setfromqcc(dec->cp, qcc);