📄 tif_fax3.c
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/* $Id: tif_fax3.c,v 1.4 2004/10/16 15:34:33 drolon Exp $ */
/*
* Copyright (c) 1990-1997 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.
*/
#include "tiffiop.h"
#ifdef CCITT_SUPPORT
/*
* TIFF Library.
*
* CCITT Group 3 (T.4) and Group 4 (T.6) Compression Support.
*
* This file contains support for decoding and encoding TIFF
* compression algorithms 2, 3, 4, and 32771.
*
* Decoder support is derived, with permission, from the code
* in Frank Cringle's viewfax program;
* Copyright (C) 1990, 1995 Frank D. Cringle.
*/
#include "tif_fax3.h"
#define G3CODES
#include "t4.h"
#include <stdio.h>
/*
* Compression+decompression state blocks are
* derived from this ``base state'' block.
*/
typedef struct {
int rw_mode; /* O_RDONLY for decode, else encode */
int mode; /* operating mode */
uint32 rowbytes; /* bytes in a decoded scanline */
uint32 rowpixels; /* pixels in a scanline */
uint16 cleanfaxdata; /* CleanFaxData tag */
uint32 badfaxrun; /* BadFaxRun tag */
uint32 badfaxlines; /* BadFaxLines tag */
uint32 groupoptions; /* Group 3/4 options tag */
uint32 recvparams; /* encoded Class 2 session params */
char* subaddress; /* subaddress string */
uint32 recvtime; /* time spent receiving (secs) */
TIFFVGetMethod vgetparent; /* super-class method */
TIFFVSetMethod vsetparent; /* super-class method */
} Fax3BaseState;
#define Fax3State(tif) ((Fax3BaseState*) (tif)->tif_data)
typedef enum { G3_1D, G3_2D } Ttag;
typedef struct {
Fax3BaseState b;
/* Decoder state info */
const unsigned char* bitmap; /* bit reversal table */
uint32 data; /* current i/o byte/word */
int bit; /* current i/o bit in byte */
int EOLcnt; /* count of EOL codes recognized */
TIFFFaxFillFunc fill; /* fill routine */
uint32* runs; /* b&w runs for current/previous row */
uint32* refruns; /* runs for reference line */
uint32* curruns; /* runs for current line */
/* Encoder state info */
Ttag tag; /* encoding state */
unsigned char* refline; /* reference line for 2d decoding */
int k; /* #rows left that can be 2d encoded */
int maxk; /* max #rows that can be 2d encoded */
} Fax3CodecState;
#define DecoderState(tif) ((Fax3CodecState*) Fax3State(tif))
#define EncoderState(tif) ((Fax3CodecState*) Fax3State(tif))
#define is2DEncoding(sp) \
(sp->b.groupoptions & GROUP3OPT_2DENCODING)
#define isAligned(p,t) ((((unsigned long)(p)) & (sizeof (t)-1)) == 0)
/*
* Group 3 and Group 4 Decoding.
*/
/*
* These macros glue the TIFF library state to
* the state expected by Frank's decoder.
*/
#define DECLARE_STATE(tif, sp, mod) \
static const char module[] = mod; \
Fax3CodecState* sp = DecoderState(tif); \
int a0; /* reference element */ \
int lastx = sp->b.rowpixels; /* last element in row */ \
uint32 BitAcc; /* bit accumulator */ \
int BitsAvail; /* # valid bits in BitAcc */ \
int RunLength; /* length of current run */ \
unsigned char* cp; /* next byte of input data */ \
unsigned char* ep; /* end of input data */ \
uint32* pa; /* place to stuff next run */ \
uint32* thisrun; /* current row's run array */ \
int EOLcnt; /* # EOL codes recognized */ \
const unsigned char* bitmap = sp->bitmap; /* input data bit reverser */ \
const TIFFFaxTabEnt* TabEnt
#define DECLARE_STATE_2D(tif, sp, mod) \
DECLARE_STATE(tif, sp, mod); \
int b1; /* next change on prev line */ \
uint32* pb /* next run in reference line */\
/*
* Load any state that may be changed during decoding.
*/
#define CACHE_STATE(tif, sp) do { \
BitAcc = sp->data; \
BitsAvail = sp->bit; \
EOLcnt = sp->EOLcnt; \
cp = (unsigned char*) tif->tif_rawcp; \
ep = cp + tif->tif_rawcc; \
} while (0)
/*
* Save state possibly changed during decoding.
*/
#define UNCACHE_STATE(tif, sp) do { \
sp->bit = BitsAvail; \
sp->data = BitAcc; \
sp->EOLcnt = EOLcnt; \
tif->tif_rawcc -= (tidata_t) cp - tif->tif_rawcp; \
tif->tif_rawcp = (tidata_t) cp; \
} while (0)
/*
* Setup state for decoding a strip.
*/
static int
Fax3PreDecode(TIFF* tif, tsample_t s)
{
Fax3CodecState* sp = DecoderState(tif);
(void) s;
assert(sp != NULL);
sp->bit = 0; /* force initial read */
sp->data = 0;
sp->EOLcnt = 0; /* force initial scan for EOL */
/*
* Decoder assumes lsb-to-msb bit order. Note that we select
* this here rather than in Fax3SetupState so that viewers can
* hold the image open, fiddle with the FillOrder tag value,
* and then re-decode the image. Otherwise they'd need to close
* and open the image to get the state reset.
*/
sp->bitmap =
TIFFGetBitRevTable(tif->tif_dir.td_fillorder != FILLORDER_LSB2MSB);
if (sp->refruns) { /* init reference line to white */
sp->refruns[0] = (uint32) sp->b.rowpixels;
sp->refruns[1] = 0;
}
return (1);
}
/*
* Routine for handling various errors/conditions.
* Note how they are "glued into the decoder" by
* overriding the definitions used by the decoder.
*/
static void
Fax3Unexpected(const char* module, TIFF* tif, uint32 a0)
{
TIFFError(module, "%s: Bad code word at scanline %d (x %lu)",
tif->tif_name, tif->tif_row, (unsigned long) a0);
}
#define unexpected(table, a0) Fax3Unexpected(module, tif, a0)
static void
Fax3Extension(const char* module, TIFF* tif, uint32 a0)
{
TIFFError(module,
"%s: Uncompressed data (not supported) at scanline %d (x %lu)",
tif->tif_name, tif->tif_row, (unsigned long) a0);
}
#define extension(a0) Fax3Extension(module, tif, a0)
static void
Fax3BadLength(const char* module, TIFF* tif, uint32 a0, uint32 lastx)
{
TIFFWarning(module, "%s: %s at scanline %d (got %lu, expected %lu)",
tif->tif_name,
a0 < lastx ? "Premature EOL" : "Line length mismatch",
tif->tif_row, (unsigned long) a0, (unsigned long) lastx);
}
#define badlength(a0,lastx) Fax3BadLength(module, tif, a0, lastx)
static void
Fax3PrematureEOF(const char* module, TIFF* tif, uint32 a0)
{
TIFFWarning(module, "%s: Premature EOF at scanline %d (x %lu)",
tif->tif_name, tif->tif_row, (unsigned long) a0);
}
#define prematureEOF(a0) Fax3PrematureEOF(module, tif, a0)
#define Nop
/*
* Decode the requested amount of G3 1D-encoded data.
*/
static int
Fax3Decode1D(TIFF* tif, tidata_t buf, tsize_t occ, tsample_t s)
{
DECLARE_STATE(tif, sp, "Fax3Decode1D");
(void) s;
CACHE_STATE(tif, sp);
thisrun = sp->curruns;
while ((long)occ > 0) {
a0 = 0;
RunLength = 0;
pa = thisrun;
#ifdef FAX3_DEBUG
printf("\nBitAcc=%08X, BitsAvail = %d\n", BitAcc, BitsAvail);
printf("-------------------- %d\n", tif->tif_row);
fflush(stdout);
#endif
SYNC_EOL(EOF1D);
EXPAND1D(EOF1Da);
(*sp->fill)(buf, thisrun, pa, lastx);
buf += sp->b.rowbytes;
occ -= sp->b.rowbytes;
continue;
EOF1D: /* premature EOF */
CLEANUP_RUNS();
EOF1Da: /* premature EOF */
(*sp->fill)(buf, thisrun, pa, lastx);
UNCACHE_STATE(tif, sp);
return (-1);
}
UNCACHE_STATE(tif, sp);
return (1);
}
#define SWAP(t,a,b) { t x; x = (a); (a) = (b); (b) = x; }
/*
* Decode the requested amount of G3 2D-encoded data.
*/
static int
Fax3Decode2D(TIFF* tif, tidata_t buf, tsize_t occ, tsample_t s)
{
DECLARE_STATE_2D(tif, sp, "Fax3Decode2D");
int is1D; /* current line is 1d/2d-encoded */
(void) s;
CACHE_STATE(tif, sp);
while ((long)occ > 0) {
a0 = 0;
RunLength = 0;
pa = thisrun = sp->curruns;
#ifdef FAX3_DEBUG
printf("\nBitAcc=%08X, BitsAvail = %d EOLcnt = %d",
BitAcc, BitsAvail, EOLcnt);
#endif
SYNC_EOL(EOF2D);
NeedBits8(1, EOF2D);
is1D = GetBits(1); /* 1D/2D-encoding tag bit */
ClrBits(1);
#ifdef FAX3_DEBUG
printf(" %s\n-------------------- %d\n",
is1D ? "1D" : "2D", tif->tif_row);
fflush(stdout);
#endif
pb = sp->refruns;
b1 = *pb++;
if (is1D)
EXPAND1D(EOF2Da);
else
EXPAND2D(EOF2Da);
(*sp->fill)(buf, thisrun, pa, lastx);
SETVAL(0); /* imaginary change for reference */
SWAP(uint32*, sp->curruns, sp->refruns);
buf += sp->b.rowbytes;
occ -= sp->b.rowbytes;
continue;
EOF2D: /* premature EOF */
CLEANUP_RUNS();
EOF2Da: /* premature EOF */
(*sp->fill)(buf, thisrun, pa, lastx);
UNCACHE_STATE(tif, sp);
return (-1);
}
UNCACHE_STATE(tif, sp);
return (1);
}
#undef SWAP
/*
* The ZERO & FILL macros must handle spans < 2*sizeof(long) bytes.
* For machines with 64-bit longs this is <16 bytes; otherwise
* this is <8 bytes. We optimize the code here to reflect the
* machine characteristics.
*/
#if SIZEOF_LONG == 8
# define FILL(n, cp) \
switch (n) { \
case 15:(cp)[14] = 0xff; case 14:(cp)[13] = 0xff; case 13: (cp)[12] = 0xff;\
case 12:(cp)[11] = 0xff; case 11:(cp)[10] = 0xff; case 10: (cp)[9] = 0xff;\
case 9: (cp)[8] = 0xff; case 8: (cp)[7] = 0xff; case 7: (cp)[6] = 0xff;\
case 6: (cp)[5] = 0xff; case 5: (cp)[4] = 0xff; case 4: (cp)[3] = 0xff;\
case 3: (cp)[2] = 0xff; case 2: (cp)[1] = 0xff; \
case 1: (cp)[0] = 0xff; (cp) += (n); case 0: ; \
}
# define ZERO(n, cp) \
switch (n) { \
case 15:(cp)[14] = 0; case 14:(cp)[13] = 0; case 13: (cp)[12] = 0; \
case 12:(cp)[11] = 0; case 11:(cp)[10] = 0; case 10: (cp)[9] = 0; \
case 9: (cp)[8] = 0; case 8: (cp)[7] = 0; case 7: (cp)[6] = 0; \
case 6: (cp)[5] = 0; case 5: (cp)[4] = 0; case 4: (cp)[3] = 0; \
case 3: (cp)[2] = 0; case 2: (cp)[1] = 0; \
case 1: (cp)[0] = 0; (cp) += (n); case 0: ; \
}
#else
# define FILL(n, cp) \
switch (n) { \
case 7: (cp)[6] = 0xff; case 6: (cp)[5] = 0xff; case 5: (cp)[4] = 0xff; \
case 4: (cp)[3] = 0xff; case 3: (cp)[2] = 0xff; case 2: (cp)[1] = 0xff; \
case 1: (cp)[0] = 0xff; (cp) += (n); case 0: ; \
}
# define ZERO(n, cp) \
switch (n) { \
case 7: (cp)[6] = 0; case 6: (cp)[5] = 0; case 5: (cp)[4] = 0; \
case 4: (cp)[3] = 0; case 3: (cp)[2] = 0; case 2: (cp)[1] = 0; \
case 1: (cp)[0] = 0; (cp) += (n); case 0: ; \
}
#endif
/*
* Bit-fill a row according to the white/black
* runs generated during G3/G4 decoding.
*/
void
_TIFFFax3fillruns(unsigned char* buf, uint32* runs, uint32* erun, uint32 lastx)
{
static const unsigned char _fillmasks[] =
{ 0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff };
unsigned char* cp;
uint32 x, bx, run;
int32 n, nw;
long* lp;
if ((erun-runs)&1)
*erun++ = 0;
x = 0;
for (; runs < erun; runs += 2) {
run = runs[0];
if (x+run > lastx || run > lastx )
run = runs[0] = (uint32) (lastx - x);
if (run) {
cp = buf + (x>>3);
bx = x&7;
if (run > 8-bx) {
if (bx) { /* align to byte boundary */
*cp++ &= 0xff << (8-bx);
run -= 8-bx;
}
if( (n = run >> 3) != 0 ) { /* multiple bytes to fill */
if ((n/sizeof (long)) > 1) {
/*
* Align to longword boundary and fill.
*/
for (; n && !isAligned(cp, long); n--)
*cp++ = 0x00;
lp = (long*) cp;
nw = (int32)(n / sizeof (long));
n -= nw * sizeof (long);
do {
*lp++ = 0L;
} while (--nw);
cp = (unsigned char*) lp;
}
ZERO(n, cp);
run &= 7;
}
if (run)
cp[0] &= 0xff >> run;
} else
cp[0] &= ~(_fillmasks[run]>>bx);
x += runs[0];
}
run = runs[1];
if (x+run > lastx || run > lastx )
run = runs[1] = lastx - x;
if (run) {
cp = buf + (x>>3);
bx = x&7;
if (run > 8-bx) {
if (bx) { /* align to byte boundary */
*cp++ |= 0xff >> bx;
run -= 8-bx;
}
if( (n = run>>3) != 0 ) { /* multiple bytes to fill */
if ((n/sizeof (long)) > 1) {
/*
* Align to longword boundary and fill.
*/
for (; n && !isAligned(cp, long); n--)
*cp++ = 0xff;
lp = (long*) cp;
nw = (int32)(n / sizeof (long));
n -= nw * sizeof (long);
do {
*lp++ = -1L;
} while (--nw);
cp = (unsigned char*) lp;
}
FILL(n, cp);
run &= 7;
}
if (run)
cp[0] |= 0xff00 >> run;
} else
cp[0] |= _fillmasks[run]>>bx;
x += runs[1];
}
}
assert(x == lastx);
}
#undef ZERO
#undef FILL
static char *
CheckMalloc(TIFF* tif, size_t nmemb, size_t elem_size, const char* what)
{
char *cp = NULL;
tsize_t bytes = nmemb * elem_size;
if (elem_size && bytes / elem_size == nmemb)
cp = (char*) _TIFFmalloc(bytes);
if (cp == NULL)
TIFFError(tif->tif_name, "No space %s", what);
return (cp);
}
/*
* Setup G3/G4-related compression/decompression state
* before data is processed. This routine is called once
* per image -- it sets up different state based on whether
* or not decoding or encoding is being done and whether
* 1D- or 2D-encoded data is involved.
*/
static int
Fax3SetupState(TIFF* tif)
{
TIFFDirectory* td = &tif->tif_dir;
Fax3BaseState* sp = Fax3State(tif);
long rowbytes, rowpixels;
int needsRefLine;
Fax3CodecState* dsp = (Fax3CodecState*) Fax3State(tif);
uint32 nruns;
if (td->td_bitspersample != 1) {
TIFFError(tif->tif_name,
"Bits/sample must be 1 for Group 3/4 encoding/decoding");
return (0);
}
/*
* Calculate the scanline/tile widths.
*/
if (isTiled(tif)) {
rowbytes = TIFFTileRowSize(tif);
rowpixels = td->td_tilewidth;
} else {
rowbytes = TIFFScanlineSize(tif);
rowpixels = td->td_imagewidth;
}
sp->rowbytes = (uint32) rowbytes;
sp->rowpixels = (uint32) rowpixels;
/*
* Allocate any additional space required for decoding/encoding.
*/
needsRefLine = (
(sp->groupoptions & GROUP3OPT_2DENCODING) ||
td->td_compression == COMPRESSION_CCITTFAX4
);
nruns = needsRefLine ? 2*TIFFroundup(rowpixels,32) : rowpixels;
dsp->runs = (uint32*) CheckMalloc(tif, 2*nruns+3, sizeof (uint32),
"for Group 3/4 run arrays");
if (dsp->runs == NULL)
return (0);
dsp->curruns = dsp->runs;
if (needsRefLine)
dsp->refruns = dsp->runs + (nruns>>1);
else
dsp->refruns = NULL;
if (is2DEncoding(dsp)) { /* NB: default is 1D routine */
tif->tif_decoderow = Fax3Decode2D;
tif->tif_decodestrip = Fax3Decode2D;
tif->tif_decodetile = Fax3Decode2D;
}
if (needsRefLine) { /* 2d encoding */
Fax3CodecState* esp = EncoderState(tif);
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