[wxWidgets.git] / src / tiff / tif_predict.c

/* $Header$ */

/*
 * Copyright (c) 1988-1997 Sam Leffler
 * Copyright (c) 1991-1997 Silicon Graphics, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and
 * its documentation for any purpose is hereby granted without fee, provided
 * that (i) the above copyright notices and this permission notice appear in
 * all copies of the software and related documentation, and (ii) the names of
 * Sam Leffler and Silicon Graphics may not be used in any advertising or
 * publicity relating to the software without the specific, prior written
 * permission of Sam Leffler and Silicon Graphics.
 *
 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
 *
 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */

/*
 * TIFF Library.
 *
 * Predictor Tag Support (used by multiple codecs).
 */
#include "tiffiop.h"
/* Watcom C++ (or its make utility) doesn't like long filenames */
#ifdef wxUSE_SHORTNAMES
#include "tif_pred.h"
#else
#include "tif_predict.h"
#endif

#include <assert.h>

#define	PredictorState(tif)	((TIFFPredictorState*) (tif)->tif_data)

static	void LINKAGEMODE horAcc8(TIFF*, tidata_t, tsize_t);
static	void LINKAGEMODE horAcc16(TIFF*, tidata_t, tsize_t);
static	void LINKAGEMODE swabHorAcc16(TIFF*, tidata_t, tsize_t);
static	void LINKAGEMODE horDiff8(TIFF*, tidata_t, tsize_t);
static	void LINKAGEMODE horDiff16(TIFF*, tidata_t, tsize_t);
static	int LINKAGEMODE PredictorDecodeRow(TIFF*, tidata_t, tsize_t, tsample_t);
static	int LINKAGEMODE PredictorDecodeTile(TIFF*, tidata_t, tsize_t, tsample_t);
static	int LINKAGEMODE PredictorEncodeRow(TIFF*, tidata_t, tsize_t, tsample_t);
static	int LINKAGEMODE PredictorEncodeTile(TIFF*, tidata_t, tsize_t, tsample_t);

static int
PredictorSetup(TIFF* tif)
{
	TIFFPredictorState* sp = PredictorState(tif);
	TIFFDirectory* td = &tif->tif_dir;

	if (sp->predictor == 1)		/* no differencing */
		return (1);
	if (sp->predictor != 2) {
		TIFFError(tif->tif_name, "\"Predictor\" value %d not supported",
		    sp->predictor);
		return (0);
	}
	if (td->td_bitspersample != 8 && td->td_bitspersample != 16) {
		TIFFError(tif->tif_name,
    "Horizontal differencing \"Predictor\" not supported with %d-bit samples",
		    td->td_bitspersample);
		return (0);
	}
	sp->stride = (td->td_planarconfig == PLANARCONFIG_CONTIG ?
	    td->td_samplesperpixel : 1);
	/*
	 * Calculate the scanline/tile-width size in bytes.
	 */
	if (isTiled(tif))
		sp->rowsize = TIFFTileRowSize(tif);
	else
		sp->rowsize = TIFFScanlineSize(tif);
	return (1);
}

static int
PredictorSetupDecode(TIFF* tif)
{
	TIFFPredictorState* sp = PredictorState(tif);
	TIFFDirectory* td = &tif->tif_dir;

	if (!(*sp->setupdecode)(tif) || !PredictorSetup(tif))
		return (0);
	if (sp->predictor == 2) {
		switch (td->td_bitspersample) {
		case 8:  sp->pfunc = horAcc8; break;
		case 16: sp->pfunc = horAcc16; break;
		}
		/*
		 * Override default decoding method with
		 * one that does the predictor stuff.
		 */
		sp->coderow = tif->tif_decoderow;
		tif->tif_decoderow = PredictorDecodeRow;
		sp->codestrip = tif->tif_decodestrip;
		tif->tif_decodestrip = PredictorDecodeTile;
		sp->codetile = tif->tif_decodetile;
		tif->tif_decodetile = PredictorDecodeTile;
		/*
		 * If the data is horizontally differenced
		 * 16-bit data that requires byte-swapping,
		 * then it must be byte swapped before the
		 * accumulation step.  We do this with a
		 * special-purpose routine and override the
		 * normal post decoding logic that the library
		 * setup when the directory was read.
		 */
		if (tif->tif_flags&TIFF_SWAB) {
			if (sp->pfunc == horAcc16) {
				sp->pfunc = swabHorAcc16;
				tif->tif_postdecode = _TIFFNoPostDecode;
			} /* else handle 32-bit case... */
		}
	}
	return (1);
}

static int
PredictorSetupEncode(TIFF* tif)
{
	TIFFPredictorState* sp = PredictorState(tif);
	TIFFDirectory* td = &tif->tif_dir;

	if (!(*sp->setupencode)(tif) || !PredictorSetup(tif))
		return (0);
	if (sp->predictor == 2) {
		switch (td->td_bitspersample) {
		case 8:  sp->pfunc = horDiff8; break;
		case 16: sp->pfunc = horDiff16; break;
		}
		/*
		 * Override default encoding method with
		 * one that does the predictor stuff.
		 */
		sp->coderow = tif->tif_encoderow;
		tif->tif_encoderow = PredictorEncodeRow;
		sp->codestrip = tif->tif_encodestrip;
		tif->tif_encodestrip = PredictorEncodeTile;
		sp->codetile = tif->tif_encodetile;
		tif->tif_encodetile = PredictorEncodeTile;
	}
	return (1);
}

#define REPEAT4(n, op)		\
    switch (n) {		\
    default: { int i; for (i = n-4; i > 0; i--) { op; } } \
    case 4:  op;		\
    case 3:  op;		\
    case 2:  op;		\
    case 1:  op;		\
    case 0:  ;			\
    }

static void
horAcc8(TIFF* tif, tidata_t cp0, tsize_t cc)
{
	TIFFPredictorState* sp = PredictorState(tif);
	u_int stride = sp->stride;

	char* cp = (char*) cp0;
	if (cc > stride) {
		cc -= stride;
		/*
		 * Pipeline the most common cases.
		 */
		if (stride == 3)  {
			u_int cr = cp[0];
			u_int cg = cp[1];
			u_int cb = cp[2];
			do {
				cc -= 3, cp += 3;
				cp[0] = (cr += cp[0]);
				cp[1] = (cg += cp[1]);
				cp[2] = (cb += cp[2]);
			} while ((int32) cc > 0);
		} else if (stride == 4)  {
			u_int cr = cp[0];
			u_int cg = cp[1];
			u_int cb = cp[2];
			u_int ca = cp[3];
			do {
				cc -= 4, cp += 4;
				cp[0] = (cr += cp[0]);
				cp[1] = (cg += cp[1]);
				cp[2] = (cb += cp[2]);
				cp[3] = (ca += cp[3]);
			} while ((int32) cc > 0);
		} else  {
			do {
				REPEAT4(stride, cp[stride] += *cp; cp++)
				cc -= stride;
			} while ((int32) cc > 0);
		}
	}
}

static void
swabHorAcc16(TIFF* tif, tidata_t cp0, tsize_t cc)
{
	TIFFPredictorState* sp = PredictorState(tif);
	u_int stride = sp->stride;
	uint16* wp = (uint16*) cp0;
	tsize_t wc = cc / 2;

	if (wc > stride) {
		TIFFSwabArrayOfShort(wp, wc);
		wc -= stride;
		do {
			REPEAT4(stride, wp[stride] += wp[0]; wp++)
			wc -= stride;
		} while ((int32) wc > 0);
	}
}

static void
horAcc16(TIFF* tif, tidata_t cp0, tsize_t cc)
{
	u_int stride = PredictorState(tif)->stride;
	uint16* wp = (uint16*) cp0;
	tsize_t wc = cc / 2;

	if (wc > stride) {
		wc -= stride;
		do {
			REPEAT4(stride, wp[stride] += wp[0]; wp++)
			wc -= stride;
		} while ((int32) wc > 0);
	}
}

/*
 * Decode a scanline and apply the predictor routine.
 */
static int
PredictorDecodeRow(TIFF* tif, tidata_t op0, tsize_t occ0, tsample_t s)
{
	TIFFPredictorState *sp = PredictorState(tif);

	assert(sp != NULL);
	assert(sp->coderow != NULL);
	assert(sp->pfunc != NULL);
	if ((*sp->coderow)(tif, op0, occ0, s)) {
		(*sp->pfunc)(tif, op0, occ0);
		return (1);
	} else
		return (0);
}

/*
 * Decode a tile/strip and apply the predictor routine.
 * Note that horizontal differencing must be done on a
 * row-by-row basis.  The width of a "row" has already
 * been calculated at pre-decode time according to the
 * strip/tile dimensions.
 */
static int
PredictorDecodeTile(TIFF* tif, tidata_t op0, tsize_t occ0, tsample_t s)
{
	TIFFPredictorState *sp = PredictorState(tif);

	assert(sp != NULL);
	assert(sp->codetile != NULL);
	if ((*sp->codetile)(tif, op0, occ0, s)) {
		tsize_t rowsize = sp->rowsize;
		assert(rowsize > 0);
		assert(sp->pfunc != NULL);
		while ((long)occ0 > 0) {
			(*sp->pfunc)(tif, op0, (tsize_t) rowsize);
			occ0 -= rowsize;
			op0 += rowsize;
		}
		return (1);
	} else
		return (0);
}

static void
horDiff8(TIFF* tif, tidata_t cp0, tsize_t cc)
{
	TIFFPredictorState* sp = PredictorState(tif);
	u_int stride = sp->stride;
	char* cp = (char*) cp0;

	if (cc > stride) {
		cc -= stride;
		/*
		 * Pipeline the most common cases.
		 */
		if (stride == 3) {
			int r1, g1, b1;
			int r2 = cp[0];
			int g2 = cp[1];
			int b2 = cp[2];
			do {
				r1 = cp[3]; cp[3] = r1-r2; r2 = r1;
				g1 = cp[4]; cp[4] = g1-g2; g2 = g1;
				b1 = cp[5]; cp[5] = b1-b2; b2 = b1;
				cp += 3;
			} while ((int32)(cc -= 3) > 0);
		} else if (stride == 4) {
			int r1, g1, b1, a1;
			int r2 = cp[0];
			int g2 = cp[1];
			int b2 = cp[2];
			int a2 = cp[3];
			do {
				r1 = cp[4]; cp[4] = r1-r2; r2 = r1;
				g1 = cp[5]; cp[5] = g1-g2; g2 = g1;
				b1 = cp[6]; cp[6] = b1-b2; b2 = b1;
				a1 = cp[7]; cp[7] = a1-a2; a2 = a1;
				cp += 4;
			} while ((int32)(cc -= 4) > 0);
		} else {
			cp += cc - 1;
			do {
				REPEAT4(stride, cp[stride] -= cp[0]; cp--)
			} while ((int32)(cc -= stride) > 0);
		}
	}
}

static void
horDiff16(TIFF* tif, tidata_t cp0, tsize_t cc)
{
	TIFFPredictorState* sp = PredictorState(tif);
	u_int stride = sp->stride;
	int16 *wp = (int16*) cp0;
	tsize_t wc = cc/2;

	if (wc > stride) {
		wc -= stride;
		wp += wc - 1;
		do {
			REPEAT4(stride, wp[stride] -= wp[0]; wp--)
			wc -= stride;
		} while ((int32) wc > 0);
	}
}

static int
PredictorEncodeRow(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
{
	TIFFPredictorState *sp = PredictorState(tif);

	assert(sp != NULL);
	assert(sp->pfunc != NULL);
	assert(sp->coderow != NULL);
/* XXX horizontal differencing alters user's data XXX */
	(*sp->pfunc)(tif, bp, cc);
	return ((*sp->coderow)(tif, bp, cc, s));
}

static int
PredictorEncodeTile(TIFF* tif, tidata_t bp0, tsize_t cc0, tsample_t s)
{
	TIFFPredictorState *sp = PredictorState(tif);
	tsize_t cc = cc0, rowsize;
	u_char* bp = bp0;

	assert(sp != NULL);
	assert(sp->pfunc != NULL);
	assert(sp->codetile != NULL);
	rowsize = sp->rowsize;
	assert(rowsize > 0);
	while ((long)cc > 0) {
		(*sp->pfunc)(tif, bp, (tsize_t) rowsize);
		cc -= rowsize;
		bp += rowsize;
	}
	return ((*sp->codetile)(tif, bp0, cc0, s));
}

#define	FIELD_PREDICTOR	(FIELD_CODEC+0)		/* XXX */

static const TIFFFieldInfo predictFieldInfo[] = {
    { TIFFTAG_PREDICTOR,	 1, 1, TIFF_SHORT,	FIELD_PREDICTOR,
      FALSE,	FALSE,	"Predictor" },
};
#define	N(a)	(sizeof (a) / sizeof (a[0]))

static int
PredictorVSetField(TIFF* tif, ttag_t tag, va_list ap)
{
	TIFFPredictorState *sp = PredictorState(tif);

	switch (tag) {
	case TIFFTAG_PREDICTOR:
		sp->predictor = (uint16) va_arg(ap, int);
		TIFFSetFieldBit(tif, FIELD_PREDICTOR);
		break;
	default:
		return (*sp->vsetparent)(tif, tag, ap);
	}
	tif->tif_flags |= TIFF_DIRTYDIRECT;
	return (1);
}

static int
PredictorVGetField(TIFF* tif, ttag_t tag, va_list ap)
{
	TIFFPredictorState *sp = PredictorState(tif);

	switch (tag) {
	case TIFFTAG_PREDICTOR:
		*va_arg(ap, uint16*) = sp->predictor;
		break;
	default:
		return (*sp->vgetparent)(tif, tag, ap);
	}
	return (1);
}

static void LINKAGEMODE
PredictorPrintDir(TIFF* tif, FILE* fd, long flags)
{
	TIFFPredictorState* sp = PredictorState(tif);

	(void) flags;
	if (TIFFFieldSet(tif,FIELD_PREDICTOR)) {
		fprintf(fd, "  Predictor: ");
		switch (sp->predictor) {
		case 1: fprintf(fd, "none "); break;
		case 2: fprintf(fd, "horizontal differencing "); break;
		}
		fprintf(fd, "%u (0x%x)\n", sp->predictor, sp->predictor);
	}
	if (sp->printdir)
		(*sp->printdir)(tif, fd, flags);
}

int
TIFFPredictorInit(TIFF* tif)
{
	TIFFPredictorState* sp = PredictorState(tif);

	/*
	 * Merge codec-specific tag information and
	 * override parent get/set field methods.
	 */
	_TIFFMergeFieldInfo(tif, predictFieldInfo, N(predictFieldInfo));
	sp->vgetparent = tif->tif_vgetfield;
	tif->tif_vgetfield = PredictorVGetField;/* hook for predictor tag */
	sp->vsetparent = tif->tif_vsetfield;
	tif->tif_vsetfield = PredictorVSetField;/* hook for predictor tag */
	sp->printdir = tif->tif_printdir;
	tif->tif_printdir = PredictorPrintDir;	/* hook for predictor tag */

	sp->setupdecode = tif->tif_setupdecode;
	tif->tif_setupdecode = PredictorSetupDecode;
	sp->setupencode = tif->tif_setupencode;
	tif->tif_setupencode = PredictorSetupEncode;

	sp->predictor = 1;			/* default value */
	sp->pfunc = NULL;			/* no predictor routine */
	return (1);
}
Commit	Line	Data
b47c832e RR	1	/* $Header$ */
	2
	3	/*
	4	* Copyright (c) 1988-1997 Sam Leffler
	5	* Copyright (c) 1991-1997 Silicon Graphics, Inc.
	6	*
615a9936	7	* Permission to use, copy, modify, distribute, and sell this software and
b47c832e RR	8	* its documentation for any purpose is hereby granted without fee, provided
	9	* that (i) the above copyright notices and this permission notice appear in
	10	* all copies of the software and related documentation, and (ii) the names of
	11	* Sam Leffler and Silicon Graphics may not be used in any advertising or
	12	* publicity relating to the software without the specific, prior written
	13	* permission of Sam Leffler and Silicon Graphics.
615a9936 DW	14	*
	15	* THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
	16	* EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
	17	* WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
	18	*
b47c832e RR	19	* IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
	20	* ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
	21	* OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
615a9936 DW	22	* WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
615a9936 DW	23	* LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
b47c832e RR	24	* OF THIS SOFTWARE.
	25	*/
	26
	27	/*
	28	* TIFF Library.
	29	*
	30	* Predictor Tag Support (used by multiple codecs).
	31	*/
	32	#include "tiffiop.h"
f6bcfd97	33	/* Watcom C++ (or its make utility) doesn't like long filenames */
c9b6238d	34	#ifdef wxUSE_SHORTNAMES
f6bcfd97 BP	35	#include "tif_pred.h"
f6bcfd97 BP	36	#else
b47c832e	37	#include "tif_predict.h"
f6bcfd97	38	#endif
b47c832e RR	39
	40	#include <assert.h>
	41
	42	#define PredictorState(tif) ((TIFFPredictorState*) (tif)->tif_data)
	43
615a9936 DW	44	static void LINKAGEMODE horAcc8(TIFF*, tidata_t, tsize_t);
	45	static void LINKAGEMODE horAcc16(TIFF*, tidata_t, tsize_t);
	46	static void LINKAGEMODE swabHorAcc16(TIFF*, tidata_t, tsize_t);
	47	static void LINKAGEMODE horDiff8(TIFF*, tidata_t, tsize_t);
	48	static void LINKAGEMODE horDiff16(TIFF*, tidata_t, tsize_t);
	49	static int LINKAGEMODE PredictorDecodeRow(TIFF*, tidata_t, tsize_t, tsample_t);
	50	static int LINKAGEMODE PredictorDecodeTile(TIFF*, tidata_t, tsize_t, tsample_t);
	51	static int LINKAGEMODE PredictorEncodeRow(TIFF*, tidata_t, tsize_t, tsample_t);
	52	static int LINKAGEMODE PredictorEncodeTile(TIFF*, tidata_t, tsize_t, tsample_t);
b47c832e RR	53
	54	static int
	55	PredictorSetup(TIFF* tif)
	56	{
	57	TIFFPredictorState* sp = PredictorState(tif);
	58	TIFFDirectory* td = &tif->tif_dir;
	59
	60	if (sp->predictor == 1) /* no differencing */
	61	return (1);
	62	if (sp->predictor != 2) {
	63	TIFFError(tif->tif_name, "\"Predictor\" value %d not supported",
	64	sp->predictor);
	65	return (0);
	66	}
	67	if (td->td_bitspersample != 8 && td->td_bitspersample != 16) {
	68	TIFFError(tif->tif_name,
	69	"Horizontal differencing \"Predictor\" not supported with %d-bit samples",
	70	td->td_bitspersample);
	71	return (0);
	72	}
	73	sp->stride = (td->td_planarconfig == PLANARCONFIG_CONTIG ?
	74	td->td_samplesperpixel : 1);
	75	/*
	76	* Calculate the scanline/tile-width size in bytes.
	77	*/
	78	if (isTiled(tif))
	79	sp->rowsize = TIFFTileRowSize(tif);
	80	else
	81	sp->rowsize = TIFFScanlineSize(tif);
	82	return (1);
	83	}
	84
	85	static int
	86	PredictorSetupDecode(TIFF* tif)
	87	{
	88	TIFFPredictorState* sp = PredictorState(tif);
	89	TIFFDirectory* td = &tif->tif_dir;
	90
	91	if (!(*sp->setupdecode)(tif) \|\| !PredictorSetup(tif))
	92	return (0);
	93	if (sp->predictor == 2) {
	94	switch (td->td_bitspersample) {
	95	case 8: sp->pfunc = horAcc8; break;
	96	case 16: sp->pfunc = horAcc16; break;
	97	}
	98	/*
	99	* Override default decoding method with
	100	* one that does the predictor stuff.
	101	*/
	102	sp->coderow = tif->tif_decoderow;
	103	tif->tif_decoderow = PredictorDecodeRow;
	104	sp->codestrip = tif->tif_decodestrip;
	105	tif->tif_decodestrip = PredictorDecodeTile;
	106	sp->codetile = tif->tif_decodetile;
	107	tif->tif_decodetile = PredictorDecodeTile;
	108	/*
	109	* If the data is horizontally differenced
	110	* 16-bit data that requires byte-swapping,
	111	* then it must be byte swapped before the
	112	* accumulation step. We do this with a
	113	* special-purpose routine and override the
	114	* normal post decoding logic that the library
	115	* setup when the directory was read.
	116	*/
117	if (tif->tif_flags&TIFF_SWAB) {
118	if (sp->pfunc == horAcc16) {
119	sp->pfunc = swabHorAcc16;
120	tif->tif_postdecode = _TIFFNoPostDecode;
121	} /* else handle 32-bit case... */
122	}
123	}
124	return (1);
125	}
126
127	static int
128	PredictorSetupEncode(TIFF* tif)
129	{
130	TIFFPredictorState* sp = PredictorState(tif);
131	TIFFDirectory* td = &tif->tif_dir;
132
133	if (!(*sp->setupencode)(tif) \|\| !PredictorSetup(tif))
134	return (0);
135	if (sp->predictor == 2) {
136	switch (td->td_bitspersample) {
137	case 8: sp->pfunc = horDiff8; break;
138	case 16: sp->pfunc = horDiff16; break;
139	}
140	/*
141	* Override default encoding method with
142	* one that does the predictor stuff.
143	*/
144	sp->coderow = tif->tif_encoderow;
145	tif->tif_encoderow = PredictorEncodeRow;
146	sp->codestrip = tif->tif_encodestrip;
147	tif->tif_encodestrip = PredictorEncodeTile;
148	sp->codetile = tif->tif_encodetile;
149	tif->tif_encodetile = PredictorEncodeTile;
150	}
151	return (1);
152	}
153
154	#define REPEAT4(n, op) \
155	switch (n) { \
156	default: { int i; for (i = n-4; i > 0; i--) { op; } } \
157	case 4: op; \
158	case 3: op; \
159	case 2: op; \
160	case 1: op; \
161	case 0: ; \
162	}
163
164	static void
165	horAcc8(TIFF* tif, tidata_t cp0, tsize_t cc)
166	{
167	TIFFPredictorState* sp = PredictorState(tif);
168	u_int stride = sp->stride;
169
170	char* cp = (char*) cp0;
171	if (cc > stride) {
172	cc -= stride;
173	/*
174	* Pipeline the most common cases.
175	*/
176	if (stride == 3) {
177	u_int cr = cp[0];
178	u_int cg = cp[1];
179	u_int cb = cp[2];
180	do {
181	cc -= 3, cp += 3;
182	cp[0] = (cr += cp[0]);
183	cp[1] = (cg += cp[1]);
184	cp[2] = (cb += cp[2]);
185	} while ((int32) cc > 0);
186	} else if (stride == 4) {
187	u_int cr = cp[0];
188	u_int cg = cp[1];
189	u_int cb = cp[2];
190	u_int ca = cp[3];
191	do {
192	cc -= 4, cp += 4;
193	cp[0] = (cr += cp[0]);
194	cp[1] = (cg += cp[1]);
195	cp[2] = (cb += cp[2]);
196	cp[3] = (ca += cp[3]);
197	} while ((int32) cc > 0);
198	} else {
199	do {
200	REPEAT4(stride, cp[stride] += *cp; cp++)
201	cc -= stride;
202	} while ((int32) cc > 0);
203	}
204	}
205	}
206
207	static void
208	swabHorAcc16(TIFF* tif, tidata_t cp0, tsize_t cc)
209	{
210	TIFFPredictorState* sp = PredictorState(tif);
211	u_int stride = sp->stride;
212	uint16* wp = (uint16*) cp0;
213	tsize_t wc = cc / 2;
214
215	if (wc > stride) {
216	TIFFSwabArrayOfShort(wp, wc);
217	wc -= stride;
218	do {
219	REPEAT4(stride, wp[stride] += wp[0]; wp++)
220	wc -= stride;
221	} while ((int32) wc > 0);
222	}
223	}
224
225	static void
226	horAcc16(TIFF* tif, tidata_t cp0, tsize_t cc)
227	{
228	u_int stride = PredictorState(tif)->stride;
229	uint16* wp = (uint16*) cp0;
230	tsize_t wc = cc / 2;
231
232	if (wc > stride) {
233	wc -= stride;
234	do {
235	REPEAT4(stride, wp[stride] += wp[0]; wp++)
236	wc -= stride;
237	} while ((int32) wc > 0);
238	}
239	}
240
241	/*
242	* Decode a scanline and apply the predictor routine.
243	*/
244	static int
245	PredictorDecodeRow(TIFF* tif, tidata_t op0, tsize_t occ0, tsample_t s)
246	{
247	TIFFPredictorState *sp = PredictorState(tif);
248
249	assert(sp != NULL);
250	assert(sp->coderow != NULL);
251	assert(sp->pfunc != NULL);
252	if ((*sp->coderow)(tif, op0, occ0, s)) {
253	(*sp->pfunc)(tif, op0, occ0);
254	return (1);
255	} else
256	return (0);
257	}
258
259	/*
260	* Decode a tile/strip and apply the predictor routine.
261	* Note that horizontal differencing must be done on a
262	* row-by-row basis. The width of a "row" has already
263	* been calculated at pre-decode time according to the
264	* strip/tile dimensions.
265	*/
266	static int
267	PredictorDecodeTile(TIFF* tif, tidata_t op0, tsize_t occ0, tsample_t s)
268	{
269	TIFFPredictorState *sp = PredictorState(tif);
270
271	assert(sp != NULL);
272	assert(sp->codetile != NULL);
273	if ((*sp->codetile)(tif, op0, occ0, s)) {
274	tsize_t rowsize = sp->rowsize;
275	assert(rowsize > 0);
276	assert(sp->pfunc != NULL);
277	while ((long)occ0 > 0) {
278	(*sp->pfunc)(tif, op0, (tsize_t) rowsize);
279	occ0 -= rowsize;
280	op0 += rowsize;
281	}
282	return (1);
283	} else
284	return (0);
285	}
286
287	static void
288	horDiff8(TIFF* tif, tidata_t cp0, tsize_t cc)
289	{
290	TIFFPredictorState* sp = PredictorState(tif);
291	u_int stride = sp->stride;
292	char* cp = (char*) cp0;
293
294	if (cc > stride) {
295	cc -= stride;
296	/*
297	* Pipeline the most common cases.
298	*/
299	if (stride == 3) {
300	int r1, g1, b1;
301	int r2 = cp[0];
302	int g2 = cp[1];
303	int b2 = cp[2];
304	do {
305	r1 = cp[3]; cp[3] = r1-r2; r2 = r1;
306	g1 = cp[4]; cp[4] = g1-g2; g2 = g1;
307	b1 = cp[5]; cp[5] = b1-b2; b2 = b1;
308	cp += 3;
309	} while ((int32)(cc -= 3) > 0);
310	} else if (stride == 4) {
311	int r1, g1, b1, a1;
312	int r2 = cp[0];
313	int g2 = cp[1];
314	int b2 = cp[2];
315	int a2 = cp[3];
316	do {
317	r1 = cp[4]; cp[4] = r1-r2; r2 = r1;
318	g1 = cp[5]; cp[5] = g1-g2; g2 = g1;
319	b1 = cp[6]; cp[6] = b1-b2; b2 = b1;
320	a1 = cp[7]; cp[7] = a1-a2; a2 = a1;
321	cp += 4;
322	} while ((int32)(cc -= 4) > 0);
323	} else {
324	cp += cc - 1;
325	do {
326	REPEAT4(stride, cp[stride] -= cp[0]; cp--)
327	} while ((int32)(cc -= stride) > 0);
328	}
329	}
330	}
331
332	static void
333	horDiff16(TIFF* tif, tidata_t cp0, tsize_t cc)
334	{
335	TIFFPredictorState* sp = PredictorState(tif);
336	u_int stride = sp->stride;
337	int16 wp = (int16) cp0;
338	tsize_t wc = cc/2;
339
340	if (wc > stride) {
341	wc -= stride;
342	wp += wc - 1;
343	do {
344	REPEAT4(stride, wp[stride] -= wp[0]; wp--)
345	wc -= stride;
346	} while ((int32) wc > 0);
347	}
348	}
349
350	static int
351	PredictorEncodeRow(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
352	{
353	TIFFPredictorState *sp = PredictorState(tif);
354
355	assert(sp != NULL);
356	assert(sp->pfunc != NULL);
357	assert(sp->coderow != NULL);
358	/* XXX horizontal differencing alters user's data XXX */
359	(*sp->pfunc)(tif, bp, cc);
360	return ((*sp->coderow)(tif, bp, cc, s));
361	}
362
363	static int
364	PredictorEncodeTile(TIFF* tif, tidata_t bp0, tsize_t cc0, tsample_t s)
365	{
366	TIFFPredictorState *sp = PredictorState(tif);
367	tsize_t cc = cc0, rowsize;
368	u_char* bp = bp0;
369
370	assert(sp != NULL);
371	assert(sp->pfunc != NULL);
372	assert(sp->codetile != NULL);
373	rowsize = sp->rowsize;
374	assert(rowsize > 0);
375	while ((long)cc > 0) {
376	(*sp->pfunc)(tif, bp, (tsize_t) rowsize);
377	cc -= rowsize;
378	bp += rowsize;
379	}
380	return ((*sp->codetile)(tif, bp0, cc0, s));
381	}
382
383	#define FIELD_PREDICTOR (FIELD_CODEC+0) /* XXX */
384
385	static const TIFFFieldInfo predictFieldInfo[] = {
386	{ TIFFTAG_PREDICTOR, 1, 1, TIFF_SHORT, FIELD_PREDICTOR,
387	FALSE, FALSE, "Predictor" },
388	};
389	#define N(a) (sizeof (a) / sizeof (a[0]))
390
391	static int
392	PredictorVSetField(TIFF* tif, ttag_t tag, va_list ap)
393	{
394	TIFFPredictorState *sp = PredictorState(tif);
395
396	switch (tag) {
397	case TIFFTAG_PREDICTOR:
398	sp->predictor = (uint16) va_arg(ap, int);
399	TIFFSetFieldBit(tif, FIELD_PREDICTOR);
400	break;
401	default:
402	return (*sp->vsetparent)(tif, tag, ap);
403	}
404	tif->tif_flags \|= TIFF_DIRTYDIRECT;
405	return (1);
406	}
407
408	static int
409	PredictorVGetField(TIFF* tif, ttag_t tag, va_list ap)
410	{
411	TIFFPredictorState *sp = PredictorState(tif);
412
413	switch (tag) {
414	case TIFFTAG_PREDICTOR:
415	va_arg(ap, uint16) = sp->predictor;
416	break;
417	default:
418	return (*sp->vgetparent)(tif, tag, ap);
419	}
420	return (1);
421	}
422
615a9936	423	static void LINKAGEMODE
b47c832e RR	424	PredictorPrintDir(TIFF* tif, FILE* fd, long flags)
	425	{
	426	TIFFPredictorState* sp = PredictorState(tif);
	427
	428	(void) flags;
	429	if (TIFFFieldSet(tif,FIELD_PREDICTOR)) {
	430	fprintf(fd, " Predictor: ");
	431	switch (sp->predictor) {
	432	case 1: fprintf(fd, "none "); break;
	433	case 2: fprintf(fd, "horizontal differencing "); break;
	434	}
	435	fprintf(fd, "%u (0x%x)\n", sp->predictor, sp->predictor);
	436	}
	437	if (sp->printdir)
	438	(*sp->printdir)(tif, fd, flags);
	439	}
	440
	441	int
	442	TIFFPredictorInit(TIFF* tif)
	443	{
	444	TIFFPredictorState* sp = PredictorState(tif);
	445
	446	/*
	447	* Merge codec-specific tag information and
	448	* override parent get/set field methods.
	449	*/
	450	_TIFFMergeFieldInfo(tif, predictFieldInfo, N(predictFieldInfo));
	451	sp->vgetparent = tif->tif_vgetfield;
	452	tif->tif_vgetfield = PredictorVGetField;/* hook for predictor tag */
	453	sp->vsetparent = tif->tif_vsetfield;
	454	tif->tif_vsetfield = PredictorVSetField;/* hook for predictor tag */
	455	sp->printdir = tif->tif_printdir;
	456	tif->tif_printdir = PredictorPrintDir; /* hook for predictor tag */
	457
	458	sp->setupdecode = tif->tif_setupdecode;
	459	tif->tif_setupdecode = PredictorSetupDecode;
	460	sp->setupencode = tif->tif_setupencode;
	461	tif->tif_setupencode = PredictorSetupEncode;
	462
	463	sp->predictor = 1; /* default value */
	464	sp->pfunc = NULL; /* no predictor routine */
	465	return (1);
	466	}