/* $Id: tif_predict.c,v 1.35 2015-08-31 15:05:57 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 void horAcc8(TIFF* tif, uint8* cp0, tmsize_t cc);
static void horAcc16(TIFF* tif, uint8* cp0, tmsize_t cc);
static void horAcc32(TIFF* tif, uint8* cp0, tmsize_t cc);
static void swabHorAcc16(TIFF* tif, uint8* cp0, tmsize_t cc);
static void swabHorAcc32(TIFF* tif, uint8* cp0, tmsize_t cc);
static void horDiff8(TIFF* tif, uint8* cp0, tmsize_t cc);
static void horDiff16(TIFF* tif, uint8* cp0, tmsize_t cc);
static void horDiff32(TIFF* tif, uint8* cp0, tmsize_t cc);
static void swabHorDiff16(TIFF* tif, uint8* cp0, tmsize_t cc);
static void swabHorDiff32(TIFF* tif, uint8* cp0, tmsize_t cc);
static void fpAcc(TIFF* tif, uint8* cp0, tmsize_t cc);
static void 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;
}
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;
if (!(*sp->setupdecode)(tif) || !PredictorSetup(tif))
{
(*tif->tif_cleanup)(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 ight 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 differenciation 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; } } \
case 4: op; \
case 3: op; \
case 2: op; \
case 1: op; \
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) */
static void
horAcc8(TIFF* tif, uint8* cp0, tmsize_t cc)
{
tmsize_t stride = PredictorState(tif)->stride;
unsigned char* cp = (unsigned char*) cp0;
assert((cc%stride)==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);
}
}
}
static void
swabHorAcc16(TIFF* tif, uint8* cp0, tmsize_t cc)
{
uint16* wp = (uint16*) cp0;
tmsize_t wc = cc / 2;
TIFFSwabArrayOfShort(wp, wc);
horAcc16(tif, cp0, cc);
}
static void
horAcc16(TIFF* tif, uint8* cp0, tmsize_t cc)
{
tmsize_t stride = PredictorState(tif)->stride;
uint16* wp = (uint16*) cp0;
tmsize_t wc = cc / 2;
assert((cc%(2*stride))==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);
}
}
static void
swabHorAcc32(TIFF* tif, uint8* cp0, tmsize_t cc)
{
uint32* wp = (uint32*) cp0;
tmsize_t wc = cc / 4;
TIFFSwabArrayOfLong(wp, wc);
horAcc32(tif, cp0, cc);
}
static void
horAcc32(TIFF* tif, uint8* cp0, tmsize_t cc)
{
tmsize_t stride = PredictorState(tif)->stride;
uint32* wp = (uint32*) cp0;
tmsize_t wc = cc / 4;
assert((cc%(4*stride))==0);
if (wc > stride) {
wc -= stride;
do {
REPEAT4(stride, wp[stride] += wp[0]; wp++)
wc -= stride;
} while (wc > 0);
}
}
/*
* Floating point predictor accumulation routine.
*/
static void
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 = (uint8 *)_TIFFmalloc(cc);
assert((cc%(bps*stride))==0);
if (!tmp)
return;
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);
}
/*
* 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)) {
(*sp->decodepfunc)(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, 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);
assert((occ0%rowsize)==0);
assert(sp->decodepfunc != NULL);
while (occ0 > 0) {
(*sp->decodepfunc)(tif, op0, rowsize);
occ0 -= rowsize;
op0 += rowsize;
}
return 1;
} else
return 0;
}
static void
horDiff8(TIFF* tif, uint8* cp0, tmsize_t cc)
{
TIFFPredictorState* sp = PredictorState(tif);
tmsize_t stride = sp->stride;
unsigned char* cp = (unsigned char*) cp0;
assert((cc%stride)==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);
}
}
}
static void
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;
assert((cc%(2*stride))==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);
}
}
static void
swabHorDiff16(TIFF* tif, uint8* cp0, tmsize_t cc)
{
uint16* wp = (uint16*) cp0;
tmsize_t wc = cc / 2;
horDiff16(tif, cp0, cc);
TIFFSwabArrayOfShort(wp, wc);
}
static void
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;
assert((cc%(4*stride))==0);
if (wc > stride) {
wc -= stride;
wp += wc - 1;
do {
REPEAT4(stride, wp[stride] -= wp[0]; wp--)
wc -= stride;
} while (wc > 0);
}
}
static void
swabHorDiff32(TIFF* tif, uint8* cp0, tmsize_t cc)
{
uint32* wp = (uint32*) cp0;
tmsize_t wc = cc / 4;
horDiff32(tif, cp0, cc);
TIFFSwabArrayOfLong(wp, wc);
}
/*
* Floating point predictor differencing routine.
*/
static void
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 = (uint8 *)_TIFFmalloc(cc);
assert((cc%(bps*stride))==0);
if (!tmp)
return;
_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--)
}
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 */
(*sp->encodepfunc)(tif, bp, cc);
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);
assert((cc0%rowsize)==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*) = 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, "%u (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:
*/