jpc_enc.c

用C语言实现的JPEG编码

	int i;
long startoff;
long mainhdrlen;
	jpc_enc_cp_t *cp;
	jpc_qcc_t *qcc;
	jpc_enc_tccp_t *tccp;
	uint_fast16_t cmptno;
	jpc_tsfb_band_t bandinfos[JPC_MAXBANDS];
	jpc_fix_t mctsynweight;
	jpc_enc_tcp_t *tcp;
	jpc_tsfb_t *tsfb;
	jpc_tsfb_band_t *bandinfo;
	uint_fast16_t numbands;
	uint_fast16_t bandno;
	uint_fast16_t rlvlno;
	uint_fast16_t analgain;
	jpc_fix_t absstepsize;
	char buf[1024];
	jpc_com_t *com;

	cp = enc->cp;

startoff = jas_stream_getrwcount(enc->out);

	/* Write SOC marker segment. */
	if (!(enc->mrk = jpc_ms_create(JPC_MS_SOC))) {
		return -1;
	}
	if (jpc_putms(enc->out, enc->cstate, enc->mrk)) {
		fprintf(stderr, "cannot write SOC marker\n");
		return -1;
	}
	jpc_ms_destroy(enc->mrk);
	enc->mrk = 0;

	/* Write SIZ marker segment. */
	if (!(enc->mrk = jpc_ms_create(JPC_MS_SIZ))) {
		return -1;
	}
	siz = &enc->mrk->parms.siz;
	siz->caps = 0;
	siz->xoff = cp->imgareatlx;
	siz->yoff = cp->imgareatly;
	siz->width = cp->refgrdwidth;
	siz->height = cp->refgrdheight;
	siz->tilexoff = cp->tilegrdoffx;
	siz->tileyoff = cp->tilegrdoffy;
	siz->tilewidth = cp->tilewidth;
	siz->tileheight = cp->tileheight;
	siz->numcomps = cp->numcmpts;
	siz->comps = jas_malloc(siz->numcomps * sizeof(jpc_sizcomp_t));
	assert(siz->comps);
	for (i = 0; i < JAS_CAST(int, cp->numcmpts); ++i) {
		siz->comps[i].prec = cp->ccps[i].prec;
		siz->comps[i].sgnd = cp->ccps[i].sgnd;
		siz->comps[i].hsamp = cp->ccps[i].sampgrdstepx;
		siz->comps[i].vsamp = cp->ccps[i].sampgrdstepy;
	}
	if (jpc_putms(enc->out, enc->cstate, enc->mrk)) {
		fprintf(stderr, "cannot write SIZ marker\n");
		return -1;
	}
	jpc_ms_destroy(enc->mrk);
	enc->mrk = 0;

	if (!(enc->mrk = jpc_ms_create(JPC_MS_COM))) {
		return -1;
	}
	sprintf(buf, "Creator: JasPer Version %s", jas_getversion());
	com = &enc->mrk->parms.com;
	com->len = strlen(buf);
	com->regid = JPC_COM_LATIN;
	if (!(com->data = JAS_CAST(uchar *, jas_strdup(buf)))) {
		abort();
	}
	if (jpc_putms(enc->out, enc->cstate, enc->mrk)) {
		fprintf(stderr, "cannot write COM marker\n");
		return -1;
	}
	jpc_ms_destroy(enc->mrk);
	enc->mrk = 0;

#if 0
	if (!(enc->mrk = jpc_ms_create(JPC_MS_CRG))) {
		return -1;
	}
	crg = &enc->mrk->parms.crg;
	crg->comps = jas_malloc(crg->numcomps * sizeof(jpc_crgcomp_t));
	if (jpc_putms(enc->out, enc->cstate, enc->mrk)) {
		fprintf(stderr, "cannot write CRG marker\n");
		return -1;
	}
	jpc_ms_destroy(enc->mrk);
	enc->mrk = 0;
#endif

	tcp = &cp->tcp;
	tccp = &cp->tccp;
	for (cmptno = 0; cmptno < cp->numcmpts; ++cmptno) {
		tsfb = jpc_cod_gettsfb(tccp->qmfbid, tccp->maxrlvls - 1);
		jpc_tsfb_getbands(tsfb, 0, 0, 1 << tccp->maxrlvls, 1 << tccp->maxrlvls,
		  bandinfos);
		jpc_tsfb_destroy(tsfb);
		mctsynweight = jpc_mct_getsynweight(tcp->mctid, cmptno);
		numbands = 3 * tccp->maxrlvls - 2;
		for (bandno = 0, bandinfo = bandinfos; bandno < numbands;
		  ++bandno, ++bandinfo) {
			rlvlno = (bandno) ? ((bandno - 1) / 3 + 1) : 0;
			analgain = JPC_NOMINALGAIN(tccp->qmfbid, tccp->maxrlvls,
			  rlvlno, bandinfo->orient);
			if (!tcp->intmode) {
				absstepsize = jpc_fix_div(jpc_inttofix(1 <<
				  (analgain + 1)), bandinfo->synenergywt);
			} else {
				absstepsize = jpc_inttofix(1);
			}	
			cp->ccps[cmptno].stepsizes[bandno] =
			  jpc_abstorelstepsize(absstepsize,
			  cp->ccps[cmptno].prec + analgain);
		}
		cp->ccps[cmptno].numstepsizes = numbands;
	}

	if (!(enc->mrk = jpc_ms_create(JPC_MS_COD))) {
		return -1;
	}
	cod = &enc->mrk->parms.cod;
	cod->csty = cp->tccp.csty | cp->tcp.csty;
	cod->compparms.csty = cp->tccp.csty | cp->tcp.csty;
	cod->compparms.numdlvls = cp->tccp.maxrlvls - 1;
	cod->compparms.numrlvls = cp->tccp.maxrlvls;
	cod->prg = cp->tcp.prg;
	cod->numlyrs = cp->tcp.numlyrs;
	cod->compparms.cblkwidthval = JPC_COX_CBLKSIZEEXPN(cp->tccp.cblkwidthexpn);
	cod->compparms.cblkheightval = JPC_COX_CBLKSIZEEXPN(cp->tccp.cblkheightexpn);
	cod->compparms.cblksty = cp->tccp.cblksty;
	cod->compparms.qmfbid = cp->tccp.qmfbid;
	cod->mctrans = (cp->tcp.mctid != JPC_MCT_NONE);
	if (tccp->csty & JPC_COX_PRT) {
		for (rlvlno = 0; rlvlno < tccp->maxrlvls; ++rlvlno) {
			cod->compparms.rlvls[rlvlno].parwidthval = tccp->prcwidthexpns[rlvlno];
			cod->compparms.rlvls[rlvlno].parheightval = tccp->prcheightexpns[rlvlno];
		}
	}
	if (jpc_putms(enc->out, enc->cstate, enc->mrk)) {
		fprintf(stderr, "cannot write COD marker\n");
		return -1;
	}
	jpc_ms_destroy(enc->mrk);
	enc->mrk = 0;

	if (!(enc->mrk = jpc_ms_create(JPC_MS_QCD))) {
		return -1;
	}
	qcd = &enc->mrk->parms.qcd;
	qcd->compparms.qntsty = (tccp->qmfbid == JPC_COX_INS) ?
	  JPC_QCX_SEQNT : JPC_QCX_NOQNT;
	qcd->compparms.numstepsizes = cp->ccps[0].numstepsizes;
	qcd->compparms.numguard = cp->tccp.numgbits;
	qcd->compparms.stepsizes = cp->ccps[0].stepsizes;
	if (jpc_putms(enc->out, enc->cstate, enc->mrk)) {
		return -1;
	}
	/* We do not want the step size array to be freed! */
	qcd->compparms.stepsizes = 0;
	jpc_ms_destroy(enc->mrk);
	enc->mrk = 0;

	tccp = &cp->tccp;
	for (cmptno = 1; cmptno < cp->numcmpts; ++cmptno) {
		if (!(enc->mrk = jpc_ms_create(JPC_MS_QCC))) {
			return -1;
		}
		qcc = &enc->mrk->parms.qcc;
		qcc->compno = cmptno;
		qcc->compparms.qntsty = (tccp->qmfbid == JPC_COX_INS) ?
		  JPC_QCX_SEQNT : JPC_QCX_NOQNT;
		qcc->compparms.numstepsizes = cp->ccps[cmptno].numstepsizes;
		qcc->compparms.numguard = cp->tccp.numgbits;
		qcc->compparms.stepsizes = cp->ccps[cmptno].stepsizes;
		if (jpc_putms(enc->out, enc->cstate, enc->mrk)) {
			return -1;
		}
		/* We do not want the step size array to be freed! */
		qcc->compparms.stepsizes = 0;
		jpc_ms_destroy(enc->mrk);
		enc->mrk = 0;
	}

#define MAINTLRLEN	2
	mainhdrlen = jas_stream_getrwcount(enc->out) - startoff;
	enc->len += mainhdrlen;
	if (enc->cp->totalsize != UINT_FAST32_MAX) {
		uint_fast32_t overhead;
		overhead = mainhdrlen + MAINTLRLEN;
		enc->mainbodysize = (enc->cp->totalsize >= overhead) ?
		  (enc->cp->totalsize - overhead) : 0;
	} else {
		enc->mainbodysize = UINT_FAST32_MAX;
	}

	return 0;
}

static int jpc_enc_encodemainbody(jpc_enc_t *enc)
{
	int tileno;
	int tilex;
	int tiley;
	int i;
	jpc_sot_t *sot;
	jpc_enc_tcmpt_t *comp;
	jpc_enc_tcmpt_t *endcomps;
	jpc_enc_band_t *band;
	jpc_enc_band_t *endbands;
	jpc_enc_rlvl_t *lvl;
	int rlvlno;
	jpc_qcc_t *qcc;
	jpc_cod_t *cod;
	int adjust;
	int j;
	int absbandno;
	long numbytes;
	long tilehdrlen;
	long tilelen;
	jpc_enc_tile_t *tile;
	jpc_enc_cp_t *cp;
	double rho;
	int lyrno;
	int cmptno;
	int samestepsizes;
	jpc_enc_ccp_t *ccps;
	jpc_enc_tccp_t *tccp;
int bandno;
uint_fast32_t x;
uint_fast32_t y;
int mingbits;
int actualnumbps;
jpc_fix_t mxmag;
jpc_fix_t mag;
int numgbits;

	cp = enc->cp;

	/* Avoid compile warnings. */
	numbytes = 0;

	for (tileno = 0; tileno < JAS_CAST(int, cp->numtiles); ++tileno) {
		tilex = tileno % cp->numhtiles;
		tiley = tileno / cp->numhtiles;

		if (!(enc->curtile = jpc_enc_tile_create(enc->cp, enc->image, tileno))) {
			abort();
		}

		tile = enc->curtile;

		if (jas_getdbglevel() >= 10) {
			jpc_enc_dump(enc);
		}

		endcomps = &tile->tcmpts[tile->numtcmpts];
		for (cmptno = 0, comp = tile->tcmpts; cmptno < tile->numtcmpts; ++cmptno, ++comp) {
			if (!cp->ccps[cmptno].sgnd) {
				adjust = 1 << (cp->ccps[cmptno].prec - 1);
				for (i = 0; i < jas_matrix_numrows(comp->data); ++i) {
					for (j = 0; j < jas_matrix_numcols(comp->data); ++j) {
						*jas_matrix_getref(comp->data, i, j) -= adjust;
					}
				}
			}
		}

		if (!tile->intmode) {
				endcomps = &tile->tcmpts[tile->numtcmpts];
				for (comp = tile->tcmpts; comp != endcomps; ++comp) {
					jas_matrix_asl(comp->data, JPC_FIX_FRACBITS);
				}
		}

		switch (tile->mctid) {
		case JPC_MCT_RCT:
assert(jas_image_numcmpts(enc->image) == 3);
			jpc_rct(tile->tcmpts[0].data, tile->tcmpts[1].data,
			  tile->tcmpts[2].data);
			break;
		case JPC_MCT_ICT:
assert(jas_image_numcmpts(enc->image) == 3);
			jpc_ict(tile->tcmpts[0].data, tile->tcmpts[1].data,
			  tile->tcmpts[2].data);
			break;
		default:
			break;
		}

		for (i = 0; i < jas_image_numcmpts(enc->image); ++i) {
			comp = &tile->tcmpts[i];
			jpc_tsfb_analyze(comp->tsfb, ((comp->qmfbid == JPC_COX_RFT) ? JPC_TSFB_RITIMODE : 0), comp->data);

		}


		endcomps = &tile->tcmpts[tile->numtcmpts];
		for (cmptno = 0, comp = tile->tcmpts; comp != endcomps; ++cmptno, ++comp) {
			mingbits = 0;
			absbandno = 0;
			/* All bands must have a corresponding quantizer step size,
			  even if they contain no samples and are never coded. */
			/* Some bands may not be hit by the loop below, so we must
			  initialize all of the step sizes to a sane value. */
			memset(comp->stepsizes, 0, sizeof(comp->stepsizes));
			for (rlvlno = 0, lvl = comp->rlvls; rlvlno < comp->numrlvls; ++rlvlno, ++lvl) {
				if (!lvl->bands) {
					absbandno += rlvlno ? 3 : 1;
					continue;
				}
				endbands = &lvl->bands[lvl->numbands];
				for (band = lvl->bands; band != endbands; ++band) {
					if (!band->data) {
						++absbandno;
						continue;
					}
					actualnumbps = 0;
					mxmag = 0;
					for (y = 0; y < JAS_CAST(uint_fast32_t, jas_matrix_numrows(band->data)); ++y) {
						for (x = 0; x < JAS_CAST(uint_fast32_t, jas_matrix_numcols(band->data)); ++x) {
							mag = abs(jas_matrix_get(band->data, y, x));
							if (mag > mxmag) {
								mxmag = mag;
							}
						}
					}
					if (tile->intmode) {
						actualnumbps = jpc_firstone(mxmag) + 1;
					} else {
						actualnumbps = jpc_firstone(mxmag) + 1 - JPC_FIX_FRACBITS;
					}
					numgbits = actualnumbps - (cp->ccps[cmptno].prec - 1 +
					  band->analgain);
#if 0
fprintf(stderr, "%d %d mag=%d actual=%d numgbits=%d\n", cp->ccps[cmptno].prec, band->analgain, mxmag, actualnumbps, numgbits);
#endif
					if (numgbits > mingbits) {
						mingbits = numgbits;
					}
					if (!tile->intmode) {
						band->absstepsize = jpc_fix_div(jpc_inttofix(1
						  << (band->analgain + 1)),
						  band->synweight);
					} else {
						band->absstepsize = jpc_inttofix(1);
					}
					band->stepsize = jpc_abstorelstepsize(
					  band->absstepsize, cp->ccps[cmptno].prec +
					  band->analgain);
					band->numbps = cp->tccp.numgbits +
					  JPC_QCX_GETEXPN(band->stepsize) - 1;

					if ((!tile->intmode) && band->data) {
						quantize(band->data, band->absstepsize);
					}

					comp->stepsizes[absbandno] = band->stepsize;
					++absbandno;
				}
			}

			assert(JPC_FIX_FRACBITS >= JPC_NUMEXTRABITS);
			if (!tile->intmode) {
				jas_matrix_divpow2(comp->data, JPC_FIX_FRACBITS - JPC_NUMEXTRABITS);
			} else {
				jas_matrix_asl(comp->data, JPC_NUMEXTRABITS);
			}

#if 0
fprintf(stderr, "mingbits %d\n", mingbits);
#endif
			if (mingbits > cp->tccp.numgbits) {
				fprintf(stderr, "error: too few guard bits (need at least %d)\n",
				  mingbits);
				return -1;
			}
		}

		if (!(enc->tmpstream = jas_stream_memopen(0, 0))) {
			fprintf(stderr, "cannot open tmp file\n");
			return -1;
		}

		/* Write the tile header. */
		if (!(enc->mrk = jpc_ms_create(JPC_MS_SOT))) {
			return -1;
		}
		sot = &enc->mrk->parms.sot;
		sot->len = 0;
		sot->tileno = tileno;
		sot->partno = 0;
		sot->numparts = 1;
		if (jpc_putms(enc->tmpstream, enc->cstate, enc->mrk)) {
			fprintf(stderr, "cannot write SOT marker\n");
			return -1;
		}
		jpc_ms_destroy(enc->mrk);
		enc->mrk = 0;

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

		tccp = &cp->tccp;
		for (cmptno = 0; cmptno < JAS_CAST(int, cp->numcmpts); ++cmptno) {
			comp = &tile->tcmpts[cmptno];
			if (comp->numrlvls != tccp->maxrlvls) {
				if (!(enc->mrk = jpc_ms_create(JPC_MS_COD))) {
					return -1;
				}
/* XXX = this is not really correct. we are using comp #0's precint sizes
and other characteristics */
				comp = &tile->tcmpts[0];
				cod = &enc->mrk->parms.cod;
				cod->compparms.csty = 0;
				cod->compparms.numdlvls = comp->numrlvls - 1;
				cod->prg = tile->prg;
				cod->numlyrs = tile->numlyrs;
				cod->compparms.cblkwidthval = JPC_COX_CBLKSIZEEXPN(comp->cblkwidthexpn);
				cod->compparms.cblkheightval = JPC_COX_CBLKSIZEEXPN(comp->cblkheightexpn);
				cod->compparms.cblksty = comp->cblksty;
				cod->compparms.qmfbid = comp->qmfbid;
				cod->mctrans = (tile->mctid != JPC_MCT_NONE);
				for (i = 0; i < comp->numrlvls; ++i) {
					cod->compparms.rlvls[i].parwidthval = comp->rlvls[i].prcwidthexpn;
					cod->compparms.rlvls[i].parheightval = comp->rlvls[i].prcheightexpn;
				}
				if (jpc_putms(enc->tmpstream, enc->cstate, enc->mrk)) {
					return -1;
				}
				jpc_ms_destroy(enc->mrk);
				enc->mrk = 0;
			}
		}

		for (cmptno = 0, comp = tile->tcmpts; cmptno < JAS_CAST(int, cp->numcmpts); ++cmptno, ++comp) {
			ccps = &cp->ccps[cmptno];
			if (JAS_CAST(int, ccps->numstepsizes) == comp->numstepsizes) {
				samestepsizes = 1;
				for (bandno = 0; bandno < JAS_CAST(int, ccps->numstepsizes); ++bandno) {
					if (ccps->stepsizes[bandno] != comp->stepsizes[bandno]) {
						samestepsizes = 0;
						break;
					}
				}
			} else {
				samestepsizes = 0;
			}
			if (!samestepsizes) {
				if (!(enc->mrk = jpc_ms_create(JPC_MS_QCC))) {
					return -1;
				}
				qcc = &enc->mrk->parms.qcc;
				qcc->compno = cmptno;
				qcc->compparms.numguard = cp->tccp.numgbits;
				qcc->compparms.qntsty = (comp->qmfbid == JPC_COX_INS) ?
				  JPC_QCX_SEQNT : JPC_QCX_NOQNT;
				qcc->compparms.numstepsizes = comp->numstepsizes;
				qcc->compparms.stepsizes = comp->stepsizes;
				if (jpc_putms(enc->tmpstream, enc->cstate, enc->mrk)) {
					return -1;
				}
				qcc->compparms.stepsizes = 0;
				jpc_ms_destroy(enc->mrk);
				enc->mrk = 0;
			}