/* $Id: tif_predict.c,v 1.44 2017-06-18 10:31:50 erouault Exp $ */

/*

* 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"

#include "tif_predict.h"

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

static int horAcc8(TIFF* tif, uint8* cp0, tmsize_t cc);

static int horAcc16(TIFF* tif, uint8* cp0, tmsize_t cc);

static int horAcc32(TIFF* tif, uint8* cp0, tmsize_t cc);

static int swabHorAcc16(TIFF* tif, uint8* cp0, tmsize_t cc);

static int swabHorAcc32(TIFF* tif, uint8* cp0, tmsize_t cc);

static int horDiff8(TIFF* tif, uint8* cp0, tmsize_t cc);

static int horDiff16(TIFF* tif, uint8* cp0, tmsize_t cc);

static int horDiff32(TIFF* tif, uint8* cp0, tmsize_t cc);

static int swabHorDiff16(TIFF* tif, uint8* cp0, tmsize_t cc);

static int swabHorDiff32(TIFF* tif, uint8* cp0, tmsize_t cc);

static int fpAcc(TIFF* tif, uint8* cp0, tmsize_t cc);

static int fpDiff(TIFF* tif, uint8* cp0, tmsize_t cc);

static int PredictorDecodeRow(TIFF* tif, uint8* op0, tmsize_t occ0, uint16 s);

static int PredictorDecodeTile(TIFF* tif, uint8* op0, tmsize_t occ0, uint16 s);

static int PredictorEncodeRow(TIFF* tif, uint8* bp, tmsize_t cc, uint16 s);

static int PredictorEncodeTile(TIFF* tif, uint8* bp0, tmsize_t cc0, uint16 s);

static int

PredictorSetup(TIFF* tif)

{

static const char module[] = "PredictorSetup";

TIFFPredictorState* sp = PredictorState(tif);

TIFFDirectory* td = &tif->tif_dir;

switch (sp->predictor) /* no differencing */

{

case PREDICTOR_NONE:

return 1;

case PREDICTOR_HORIZONTAL:

if (td->td_bitspersample != 8

&& td->td_bitspersample != 16

&& td->td_bitspersample != 32) {

TIFFErrorExt(tif->tif_clientdata, module,

"Horizontal differencing \"Predictor\" not supported with %d-bit samples",

td->td_bitspersample);

return 0;

}

break;

case PREDICTOR_FLOATINGPOINT:

if (td->td_sampleformat != SAMPLEFORMAT_IEEEFP) {

TIFFErrorExt(tif->tif_clientdata, module,

"Floating point \"Predictor\" not supported with %d data format",

td->td_sampleformat);

return 0;

}

if (td->td_bitspersample != 16

&& td->td_bitspersample != 24

&& td->td_bitspersample != 32

&& td->td_bitspersample != 64) { /* Should 64 be allowed? */

TIFFErrorExt(tif->tif_clientdata, module,

"Floating point \"Predictor\" not supported with %d-bit samples",

td->td_bitspersample);

return 0;

}

break;

default:

TIFFErrorExt(tif->tif_clientdata, module,

"\"Predictor\" value %d not supported",

sp->predictor);

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);

if (sp->rowsize == 0)

return 0;

return 1;

}

static int

PredictorSetupDecode(TIFF* tif)

{

TIFFPredictorState* sp = PredictorState(tif);

TIFFDirectory* td = &tif->tif_dir;

/* Note: when PredictorSetup() fails, the effets of setupdecode() */

/* will not be "cancelled" so setupdecode() might be robust to */

/* be called several times. */

if (!(*sp->setupdecode)(tif) || !PredictorSetup(tif))

return 0;

if (sp->predictor == 2) {

switch (td->td_bitspersample) {

case 8: sp->decodepfunc = horAcc8; break;

case 16: sp->decodepfunc = horAcc16; break;

case 32: sp->decodepfunc = horAcc32; break;

}

/*

* Override default decoding method with one that does the

* predictor stuff.

*/

if( tif->tif_decoderow != PredictorDecodeRow )

{

sp->decoderow = tif->tif_decoderow;

tif->tif_decoderow = PredictorDecodeRow;

sp->decodestrip = tif->tif_decodestrip;

tif->tif_decodestrip = PredictorDecodeTile;

sp->decodetile = 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->decodepfunc == horAcc16) {

sp->decodepfunc = swabHorAcc16;

tif->tif_postdecode = _TIFFNoPostDecode;

} else if (sp->decodepfunc == horAcc32) {

sp->decodepfunc = swabHorAcc32;

tif->tif_postdecode = _TIFFNoPostDecode;

}

}

}

else if (sp->predictor == 3) {

sp->decodepfunc = fpAcc;

/*

* Override default decoding method with one that does the

* predictor stuff.

*/

if( tif->tif_decoderow != PredictorDecodeRow )

{

sp->decoderow = tif->tif_decoderow;

tif->tif_decoderow = PredictorDecodeRow;

sp->decodestrip = tif->tif_decodestrip;

tif->tif_decodestrip = PredictorDecodeTile;

sp->decodetile = tif->tif_decodetile;

tif->tif_decodetile = PredictorDecodeTile;

}

/*

* The data should not be swapped outside of the floating

* point predictor, the accumulation routine should return

* byres in the native order.

*/

if (tif->tif_flags & TIFF_SWAB) {

tif->tif_postdecode = _TIFFNoPostDecode;

}

/*

* Allocate buffer to keep the decoded bytes before

* rearranging in the right order

*/

}

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->encodepfunc = horDiff8; break;

case 16: sp->encodepfunc = horDiff16; break;

case 32: sp->encodepfunc = horDiff32; break;

}

/*

* Override default encoding method with one that does the

* predictor stuff.

*/

if( tif->tif_encoderow != PredictorEncodeRow )

{

sp->encoderow = tif->tif_encoderow;

tif->tif_encoderow = PredictorEncodeRow;

sp->encodestrip = tif->tif_encodestrip;

tif->tif_encodestrip = PredictorEncodeTile;

sp->encodetile = tif->tif_encodetile;

tif->tif_encodetile = PredictorEncodeTile;

}

/*

* If the data is horizontally differenced 16-bit data that

* requires byte-swapping, then it must be byte swapped after

* the differentiation 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->encodepfunc == horDiff16) {

sp->encodepfunc = swabHorDiff16;

tif->tif_postdecode = _TIFFNoPostDecode;

} else if (sp->encodepfunc == horDiff32) {

sp->encodepfunc = swabHorDiff32;

tif->tif_postdecode = _TIFFNoPostDecode;

}

}

}

else if (sp->predictor == 3) {

sp->encodepfunc = fpDiff;

/*

* Override default encoding method with one that does the

* predictor stuff.

*/

if( tif->tif_encoderow != PredictorEncodeRow )

{

sp->encoderow = tif->tif_encoderow;

tif->tif_encoderow = PredictorEncodeRow;

sp->encodestrip = tif->tif_encodestrip;

tif->tif_encodestrip = PredictorEncodeTile;

sp->encodetile = tif->tif_encodetile;

tif->tif_encodetile = PredictorEncodeTile;

}

}

return 1;

}

#define REPEAT4(n, op) \

switch (n) { \

default: { \

tmsize_t i; for (i = n-4; i > 0; i--) { op; } } /*-fallthrough*/ \

case 4: op; /*-fallthrough*/ \

case 3: op; /*-fallthrough*/ \

case 2: op; /*-fallthrough*/ \

case 1: op; /*-fallthrough*/ \

case 0: ; \

}

/* Remarks related to C standard compliance in all below functions : */

/* - to avoid any undefined behaviour, we only operate on unsigned types */

/* since the behaviour of "overflows" is defined (wrap over) */

/* - when storing into the byte stream, we explicitly mask with 0xff so */

/* as to make icc -check=conversions happy (not necessary by the standard) */

TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW

static int

horAcc8(TIFF* tif, uint8* cp0, tmsize_t cc)

{

tmsize_t stride = PredictorState(tif)->stride;

unsigned char* cp = (unsigned char*) cp0;

if((cc%stride)!=0)

{

TIFFErrorExt(tif->tif_clientdata, "horAcc8",

"%s", "(cc%stride)!=0");

return 0;

}

if (cc > stride) {

/*

* Pipeline the most common cases.

*/

if (stride == 3) {

unsigned int cr = cp[0];

unsigned int cg = cp[1];

unsigned int cb = cp[2];

cc -= 3;

cp += 3;

while (cc>0) {

cp[0] = (unsigned char) ((cr += cp[0]) & 0xff);

cp[1] = (unsigned char) ((cg += cp[1]) & 0xff);

cp[2] = (unsigned char) ((cb += cp[2]) & 0xff);

cc -= 3;

cp += 3;

}

} else if (stride == 4) {

unsigned int cr = cp[0];

unsigned int cg = cp[1];

unsigned int cb = cp[2];

unsigned int ca = cp[3];

cc -= 4;

cp += 4;

while (cc>0) {

cp[0] = (unsigned char) ((cr += cp[0]) & 0xff);

cp[1] = (unsigned char) ((cg += cp[1]) & 0xff);

cp[2] = (unsigned char) ((cb += cp[2]) & 0xff);

cp[3] = (unsigned char) ((ca += cp[3]) & 0xff);

cc -= 4;

cp += 4;

}

} else {

cc -= stride;

do {

REPEAT4(stride, cp[stride] =

(unsigned char) ((cp[stride] + *cp) & 0xff); cp++)

cc -= stride;

} while (cc>0);

}

}

return 1;

}

static int

swabHorAcc16(TIFF* tif, uint8* cp0, tmsize_t cc)

{

uint16* wp = (uint16*) cp0;

tmsize_t wc = cc / 2;

TIFFSwabArrayOfShort(wp, wc);

return horAcc16(tif, cp0, cc);

}

TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW

static int

horAcc16(TIFF* tif, uint8* cp0, tmsize_t cc)

{

tmsize_t stride = PredictorState(tif)->stride;

uint16* wp = (uint16*) cp0;

tmsize_t wc = cc / 2;

if((cc%(2*stride))!=0)

{

TIFFErrorExt(tif->tif_clientdata, "horAcc16",

"%s", "cc%(2*stride))!=0");

return 0;

}

if (wc > stride) {

wc -= stride;

do {

REPEAT4(stride, wp[stride] = (uint16)(((unsigned int)wp[stride] + (unsigned int)wp[0]) & 0xffff); wp++)

wc -= stride;

} while (wc > 0);

}

return 1;

}

static int

swabHorAcc32(TIFF* tif, uint8* cp0, tmsize_t cc)

{

uint32* wp = (uint32*) cp0;

tmsize_t wc = cc / 4;

TIFFSwabArrayOfLong(wp, wc);

return horAcc32(tif, cp0, cc);

}

TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW

static int

horAcc32(TIFF* tif, uint8* cp0, tmsize_t cc)

{

tmsize_t stride = PredictorState(tif)->stride;

uint32* wp = (uint32*) cp0;

tmsize_t wc = cc / 4;

if((cc%(4*stride))!=0)

{

TIFFErrorExt(tif->tif_clientdata, "horAcc32",

"%s", "cc%(4*stride))!=0");

return 0;

}

if (wc > stride) {

wc -= stride;

do {

REPEAT4(stride, wp[stride] += wp[0]; wp++)

wc -= stride;

} while (wc > 0);

}

return 1;

}

/*

* Floating point predictor accumulation routine.

*/

static int

fpAcc(TIFF* tif, uint8* cp0, tmsize_t cc)

{

tmsize_t stride = PredictorState(tif)->stride;

uint32 bps = tif->tif_dir.td_bitspersample / 8;

tmsize_t wc = cc / bps;

tmsize_t count = cc;

uint8 *cp = (uint8 *) cp0;

uint8 *tmp;

if(cc%(bps*stride)!=0)

{

TIFFErrorExt(tif->tif_clientdata, "fpAcc",

"%s", "cc%(bps*stride))!=0");

return 0;

}

tmp = (uint8 *)_TIFFmalloc(cc);

if (!tmp)

return 0;

while (count > stride) {

REPEAT4(stride, cp[stride] =

(unsigned char) ((cp[stride] + cp[0]) & 0xff); cp++)

count -= stride;

}

_TIFFmemcpy(tmp, cp0, cc);

cp = (uint8 *) cp0;

for (count = 0; count < wc; count++) {

uint32 byte;

for (byte = 0; byte < bps; byte++) {

#if WORDS_BIGENDIAN

cp[bps * count + byte] = tmp[byte * wc + count];

#else

cp[bps * count + byte] =

tmp[(bps - byte - 1) * wc + count];

#endif

}

}

_TIFFfree(tmp);

return 1;

}

/*

* Decode a scanline and apply the predictor routine.

*/

static int

PredictorDecodeRow(TIFF* tif, uint8* op0, tmsize_t occ0, uint16 s)

{

TIFFPredictorState *sp = PredictorState(tif);

assert(sp != NULL);

assert(sp->decoderow != NULL);

assert(sp->decodepfunc != NULL);

if ((*sp->decoderow)(tif, op0, occ0, s)) {

return (*sp->decodepfunc)(tif, op0, occ0);

} 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, uint8* op0, tmsize_t occ0, uint16 s)

{

TIFFPredictorState *sp = PredictorState(tif);

assert(sp != NULL);

assert(sp->decodetile != NULL);

if ((*sp->decodetile)(tif, op0, occ0, s)) {

tmsize_t rowsize = sp->rowsize;

assert(rowsize > 0);

if((occ0%rowsize) !=0)

{

TIFFErrorExt(tif->tif_clientdata, "PredictorDecodeTile",

"%s", "occ0%rowsize != 0");

return 0;

}

assert(sp->decodepfunc != NULL);

while (occ0 > 0) {

if( !(*sp->decodepfunc)(tif, op0, rowsize) )

return 0;

occ0 -= rowsize;

op0 += rowsize;

}

return 1;

} else

return 0;

}

TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW

static int

horDiff8(TIFF* tif, uint8* cp0, tmsize_t cc)

{

TIFFPredictorState* sp = PredictorState(tif);

tmsize_t stride = sp->stride;

unsigned char* cp = (unsigned char*) cp0;

if((cc%stride)!=0)

{

TIFFErrorExt(tif->tif_clientdata, "horDiff8",

"%s", "(cc%stride)!=0");

return 0;

}

if (cc > stride) {

cc -= stride;

/*

* Pipeline the most common cases.

*/

if (stride == 3) {

unsigned int r1, g1, b1;

unsigned int r2 = cp[0];

unsigned int g2 = cp[1];

unsigned int b2 = cp[2];

do {

r1 = cp[3]; cp[3] = (unsigned char)((r1-r2)&0xff); r2 = r1;

g1 = cp[4]; cp[4] = (unsigned char)((g1-g2)&0xff); g2 = g1;

b1 = cp[5]; cp[5] = (unsigned char)((b1-b2)&0xff); b2 = b1;

cp += 3;

} while ((cc -= 3) > 0);

} else if (stride == 4) {

unsigned int r1, g1, b1, a1;

unsigned int r2 = cp[0];

unsigned int g2 = cp[1];

unsigned int b2 = cp[2];

unsigned int a2 = cp[3];

do {

r1 = cp[4]; cp[4] = (unsigned char)((r1-r2)&0xff); r2 = r1;

g1 = cp[5]; cp[5] = (unsigned char)((g1-g2)&0xff); g2 = g1;

b1 = cp[6]; cp[6] = (unsigned char)((b1-b2)&0xff); b2 = b1;

a1 = cp[7]; cp[7] = (unsigned char)((a1-a2)&0xff); a2 = a1;

cp += 4;

} while ((cc -= 4) > 0);

} else {

cp += cc - 1;

do {

REPEAT4(stride, cp[stride] = (unsigned char)((cp[stride] - cp[0])&0xff); cp--)

} while ((cc -= stride) > 0);

}

}

return 1;

}

TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW

static int

horDiff16(TIFF* tif, uint8* cp0, tmsize_t cc)

{

TIFFPredictorState* sp = PredictorState(tif);

tmsize_t stride = sp->stride;

uint16 *wp = (uint16*) cp0;

tmsize_t wc = cc/2;

if((cc%(2*stride))!=0)

{

TIFFErrorExt(tif->tif_clientdata, "horDiff8",

"%s", "(cc%(2*stride))!=0");

return 0;

}

if (wc > stride) {

wc -= stride;

wp += wc - 1;

do {

REPEAT4(stride, wp[stride] = (uint16)(((unsigned int)wp[stride] - (unsigned int)wp[0]) & 0xffff); wp--)

wc -= stride;

} while (wc > 0);

}

return 1;

}

static int

swabHorDiff16(TIFF* tif, uint8* cp0, tmsize_t cc)

{

uint16* wp = (uint16*) cp0;

tmsize_t wc = cc / 2;

if( !horDiff16(tif, cp0, cc) )

return 0;

TIFFSwabArrayOfShort(wp, wc);

return 1;

}

TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW

static int

horDiff32(TIFF* tif, uint8* cp0, tmsize_t cc)

{

TIFFPredictorState* sp = PredictorState(tif);

tmsize_t stride = sp->stride;

uint32 *wp = (uint32*) cp0;

tmsize_t wc = cc/4;

if((cc%(4*stride))!=0)

{

TIFFErrorExt(tif->tif_clientdata, "horDiff32",

"%s", "(cc%(4*stride))!=0");

return 0;

}

if (wc > stride) {

wc -= stride;

wp += wc - 1;

do {

REPEAT4(stride, wp[stride] -= wp[0]; wp--)

wc -= stride;

} while (wc > 0);

}

return 1;

}

static int

swabHorDiff32(TIFF* tif, uint8* cp0, tmsize_t cc)

{

uint32* wp = (uint32*) cp0;

tmsize_t wc = cc / 4;

if( !horDiff32(tif, cp0, cc) )

return 0;

TIFFSwabArrayOfLong(wp, wc);

return 1;

}

/*

* Floating point predictor differencing routine.

*/

TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW

static int

fpDiff(TIFF* tif, uint8* cp0, tmsize_t cc)

{

tmsize_t stride = PredictorState(tif)->stride;

uint32 bps = tif->tif_dir.td_bitspersample / 8;

tmsize_t wc = cc / bps;

tmsize_t count;

uint8 *cp = (uint8 *) cp0;

uint8 *tmp;

if((cc%(bps*stride))!=0)

{

TIFFErrorExt(tif->tif_clientdata, "fpDiff",

"%s", "(cc%(bps*stride))!=0");

return 0;

}

tmp = (uint8 *)_TIFFmalloc(cc);

if (!tmp)

return 0;

_TIFFmemcpy(tmp, cp0, cc);

for (count = 0; count < wc; count++) {

uint32 byte;

for (byte = 0; byte < bps; byte++) {

#if WORDS_BIGENDIAN

cp[byte * wc + count] = tmp[bps * count + byte];

#else

cp[(bps - byte - 1) * wc + count] =

tmp[bps * count + byte];

#endif

}

}

_TIFFfree(tmp);

cp = (uint8 *) cp0;

cp += cc - stride - 1;

for (count = cc; count > stride; count -= stride)

REPEAT4(stride, cp[stride] = (unsigned char)((cp[stride] - cp[0])&0xff); cp--)

return 1;

}

static int

PredictorEncodeRow(TIFF* tif, uint8* bp, tmsize_t cc, uint16 s)

{

TIFFPredictorState *sp = PredictorState(tif);

assert(sp != NULL);

assert(sp->encodepfunc != NULL);

assert(sp->encoderow != NULL);

/* XXX horizontal differencing alters user's data XXX */

if( !(*sp->encodepfunc)(tif, bp, cc) )

return 0;

return (*sp->encoderow)(tif, bp, cc, s);

}

static int

PredictorEncodeTile(TIFF* tif, uint8* bp0, tmsize_t cc0, uint16 s)

{

static const char module[] = "PredictorEncodeTile";

TIFFPredictorState *sp = PredictorState(tif);

uint8 *working_copy;

tmsize_t cc = cc0, rowsize;

unsigned char* bp;

int result_code;

assert(sp != NULL);

assert(sp->encodepfunc != NULL);

assert(sp->encodetile != NULL);

/*

* Do predictor manipulation in a working buffer to avoid altering

* the callers buffer. http://trac.osgeo.org/gdal/ticket/1965

*/

working_copy = (uint8*) _TIFFmalloc(cc0);

if( working_copy == NULL )

{

TIFFErrorExt(tif->tif_clientdata, module,

"Out of memory allocating " TIFF_SSIZE_FORMAT " byte temp buffer.",

cc0 );

return 0;

}

memcpy( working_copy, bp0, cc0 );

bp = working_copy;

rowsize = sp->rowsize;

assert(rowsize > 0);

if((cc0%rowsize)!=0)

{

TIFFErrorExt(tif->tif_clientdata, "PredictorEncodeTile",

"%s", "(cc0%rowsize)!=0");

_TIFFfree( working_copy );

return 0;

}

while (cc > 0) {

(*sp->encodepfunc)(tif, bp, rowsize);

cc -= rowsize;

bp += rowsize;

}

result_code = (*sp->encodetile)(tif, working_copy, cc0, s);

_TIFFfree( working_copy );

return result_code;

}

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

static const TIFFField predictFields[] = {

{ TIFFTAG_PREDICTOR, 1, 1, TIFF_SHORT, 0, TIFF_SETGET_UINT16, TIFF_SETGET_UINT16, FIELD_PREDICTOR, FALSE, FALSE, "Predictor", NULL },

};

static int

PredictorVSetField(TIFF* tif, uint32 tag, va_list ap)

{

TIFFPredictorState *sp = PredictorState(tif);

assert(sp != NULL);

assert(sp->vsetparent != NULL);

switch (tag) {

case TIFFTAG_PREDICTOR:

sp->predictor = (uint16) va_arg(ap, uint16_vap);

TIFFSetFieldBit(tif, FIELD_PREDICTOR);

break;

default:

return (*sp->vsetparent)(tif, tag, ap);

}

tif->tif_flags |= TIFF_DIRTYDIRECT;

return 1;

}

static int

PredictorVGetField(TIFF* tif, uint32 tag, va_list ap)

{

TIFFPredictorState *sp = PredictorState(tif);

assert(sp != NULL);

assert(sp->vgetparent != NULL);

switch (tag) {

case TIFFTAG_PREDICTOR:

*va_arg(ap, uint16*) = (uint16)sp->predictor;

break;

default:

return (*sp->vgetparent)(tif, tag, ap);

}

return 1;

}

static void

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;

case 3: fprintf(fd, "floating point predictor "); break;

}

fprintf(fd, "%d (0x%x)\n", sp->predictor, sp->predictor);

}

if (sp->printdir)

(*sp->printdir)(tif, fd, flags);

}

int

TIFFPredictorInit(TIFF* tif)

{

TIFFPredictorState* sp = PredictorState(tif);

assert(sp != 0);

/*

* Merge codec-specific tag information.

*/

if (!_TIFFMergeFields(tif, predictFields,

TIFFArrayCount(predictFields))) {

TIFFErrorExt(tif->tif_clientdata, "TIFFPredictorInit",

"Merging Predictor codec-specific tags failed");

return 0;

}

/*

* Override parent get/set field methods.

*/

sp->vgetparent = tif->tif_tagmethods.vgetfield;

tif->tif_tagmethods.vgetfield =

PredictorVGetField;/* hook for predictor tag */

sp->vsetparent = tif->tif_tagmethods.vsetfield;

tif->tif_tagmethods.vsetfield =

PredictorVSetField;/* hook for predictor tag */

sp->printdir = tif->tif_tagmethods.printdir;

tif->tif_tagmethods.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->encodepfunc = NULL; /* no predictor routine */

sp->decodepfunc = NULL; /* no predictor routine */

return 1;

}

int

TIFFPredictorCleanup(TIFF* tif)

{

TIFFPredictorState* sp = PredictorState(tif);

assert(sp != 0);

tif->tif_tagmethods.vgetfield = sp->vgetparent;

tif->tif_tagmethods.vsetfield = sp->vsetparent;

tif->tif_tagmethods.printdir = sp->printdir;

tif->tif_setupdecode = sp->setupdecode;

tif->tif_setupencode = sp->setupencode;

return 1;

}

/* vim: set ts=8 sts=8 sw=8 noet: */

/*

* Local Variables:

* mode: c

* c-basic-offset: 8

* fill-column: 78

* End:

*/