First commit - moving from LuaForge to SourceForge

1 files changed, 1566 insertions, 0 deletions

diff --git a/src/libtiff/tif_fax3.c b/src/libtiff/tif_fax3.c
new file mode 100644
index 0000000..96f5d13
--- /dev/null
+++ b/src/libtiff/tif_fax3.c
@@ -0,0 +1,1566 @@
+/* $Id: tif_fax3.c,v 1.1 2008/10/17 06:16:07 scuri 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) */
+	char*	faxdcs;			/* Table 2/T.30 encoded session params */
+	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 line, uint32 a0)
+{
+	TIFFErrorExt(tif->tif_clientdata, module, "%s: Bad code word at line %lu of %s %lu (x %lu)",
+		tif->tif_name, (unsigned long) line, isTiled(tif) ? "tile" : "strip",
+	   (unsigned long) (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip),
+	   (unsigned long) a0);
+}
+#define	unexpected(table, a0)	Fax3Unexpected(module, tif, line, a0)
+
+static void
+Fax3Extension(const char* module, TIFF* tif, uint32 line, uint32 a0)
+{
+	TIFFErrorExt(tif->tif_clientdata, module,
+	    "%s: Uncompressed data (not supported) at line %lu of %s %lu (x %lu)",
+	    tif->tif_name, (unsigned long) line, isTiled(tif) ? "tile" : "strip",
+       (unsigned long) (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip),
+       (unsigned long) a0);
+}
+#define	extension(a0)	Fax3Extension(module, tif, line, a0)
+
+static void
+Fax3BadLength(const char* module, TIFF* tif, uint32 line, uint32 a0, uint32 lastx)
+{
+	TIFFWarningExt(tif->tif_clientdata, module, "%s: %s at line %lu of %s %lu (got %lu, expected %lu)",
+	    tif->tif_name,
+	    a0 < lastx ? "Premature EOL" : "Line length mismatch",
+	    (unsigned long) line, isTiled(tif) ? "tile" : "strip",
+        (unsigned long) (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip),
+        (unsigned long) a0, lastx);
+}
+#define	badlength(a0,lastx)	Fax3BadLength(module, tif, line, a0, lastx)
+
+static void
+Fax3PrematureEOF(const char* module, TIFF* tif, uint32 line, uint32 a0)
+{
+	TIFFWarningExt(tif->tif_clientdata, module, "%s: Premature EOF at line %lu of %s %lu (x %lu)",
+	    tif->tif_name,
+	    (unsigned long) line, isTiled(tif) ? "tile" : "strip",
+        (unsigned long) (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip),
+        (unsigned long) a0);
+}
+#define	prematureEOF(a0)	Fax3PrematureEOF(module, tif, line, 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");
+        int line = 0;
+
+	(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;
+                line++;
+		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 line = 0;
+	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);
+		SETVALUE(0);		/* imaginary change for reference */
+		SWAP(uint32*, sp->curruns, sp->refruns);
+		buf += sp->b.rowbytes;
+		occ -= sp->b.rowbytes;
+                line++;
+		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
+
+/*
+ * 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);
+	int needsRefLine;
+	Fax3CodecState* dsp = (Fax3CodecState*) Fax3State(tif);
+	uint32 rowbytes, rowpixels, nruns;
+
+	if (td->td_bitspersample != 1) {
+		TIFFErrorExt(tif->tif_clientdata, 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*) _TIFFCheckMalloc(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 (td->td_compression == COMPRESSION_CCITTFAX3
+	    && 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);
+		/*
+		 * 2d encoding requires a scanline
+		 * buffer for the ``reference line''; the
+		 * scanline against which delta encoding
+		 * is referenced.  The reference line must
+		 * be initialized to be ``white'' (done elsewhere).
+		 */
+		esp->refline = (unsigned char*) _TIFFmalloc(rowbytes);
+		if (esp->refline == NULL) {
+			TIFFErrorExt(tif->tif_clientdata, "Fax3SetupState",
+			    "%s: No space for Group 3/4 reference line",
+			    tif->tif_name);
+			return (0);
+		}
+	} else					/* 1d encoding */
+		EncoderState(tif)->refline = NULL;
+
+	return (1);
+}
+
+/*
+ * CCITT Group 3 FAX Encoding.
+ */
+
+#define	Fax3FlushBits(tif, sp) {				\
+	if ((tif)->tif_rawcc >= (tif)->tif_rawdatasize)		\
+		(void) TIFFFlushData1(tif);			\
+	*(tif)->tif_rawcp++ = (tidataval_t) (sp)->data;		\
+	(tif)->tif_rawcc++;					\
+	(sp)->data = 0, (sp)->bit = 8;				\
+}
+#define	_FlushBits(tif) {					\
+	if ((tif)->tif_rawcc >= (tif)->tif_rawdatasize)		\
+		(void) TIFFFlushData1(tif);			\
+	*(tif)->tif_rawcp++ = (tidataval_t) data;		\
+	(tif)->tif_rawcc++;					\
+	data = 0, bit = 8;					\
+}
+static const int _msbmask[9] =
+    { 0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff };
+#define	_PutBits(tif, bits, length) {				\
+	while (length > bit) {					\
+		data |= bits >> (length - bit);			\
+		length -= bit;					\
+		_FlushBits(tif);				\
+	}							\
+	data |= (bits & _msbmask[length]) << (bit - length);	\
+	bit -= length;						\
+	if (bit == 0)						\
+		_FlushBits(tif);				\
+}
+	
+/*
+ * Write a variable-length bit-value to
+ * the output stream.  Values are
+ * assumed to be at most 16 bits.
+ */
+static void
+Fax3PutBits(TIFF* tif, unsigned int bits, unsigned int length)
+{
+	Fax3CodecState* sp = EncoderState(tif);
+	unsigned int bit = sp->bit;
+	int data = sp->data;
+
+	_PutBits(tif, bits, length);
+
+	sp->data = data;
+	sp->bit = bit;
+}
+
+/*
+ * Write a code to the output stream.
+ */
+#define putcode(tif, te)	Fax3PutBits(tif, (te)->code, (te)->length)
+
+#ifdef FAX3_DEBUG
+#define	DEBUG_COLOR(w) (tab == TIFFFaxWhiteCodes ? w "W" : w "B")
+#define	DEBUG_PRINT(what,len) {						\
+    int t;								\
+    printf("%08X/%-2d: %s%5d\t", data, bit, DEBUG_COLOR(what), len);	\
+    for (t = length-1; t >= 0; t--)					\
+	putchar(code & (1<<t) ? '1' : '0');				\
+    putchar('\n');							\
+}
+#endif
+
+/*
+ * Write the sequence of codes that describes
+ * the specified span of zero's or one's.  The
+ * appropriate table that holds the make-up and
+ * terminating codes is supplied.
+ */
+static void
+putspan(TIFF* tif, int32 span, const tableentry* tab)
+{
+	Fax3CodecState* sp = EncoderState(tif);
+	unsigned int bit = sp->bit;
+	int data = sp->data;
+	unsigned int code, length;
+
+	while (span >= 2624) {
+		const tableentry* te = &tab[63 + (2560>>6)];
+		code = te->code, length = te->length;
+#ifdef FAX3_DEBUG
+		DEBUG_PRINT("MakeUp", te->runlen);
+#endif
+		_PutBits(tif, code, length);
+		span -= te->runlen;
+	}
+	if (span >= 64) {
+		const tableentry* te = &tab[63 + (span>>6)];
+		assert(te->runlen == 64*(span>>6));
+		code = te->code, length = te->length;
+#ifdef FAX3_DEBUG
+		DEBUG_PRINT("MakeUp", te->runlen);
+#endif
+		_PutBits(tif, code, length);
+		span -= te->runlen;
+	}
+	code = tab[span].code, length = tab[span].length;
+#ifdef FAX3_DEBUG
+	DEBUG_PRINT("  Term", tab[span].runlen);
+#endif
+	_PutBits(tif, code, length);
+
+	sp->data = data;
+	sp->bit = bit;
+}
+
+/*
+ * Write an EOL code to the output stream.  The zero-fill
+ * logic for byte-aligning encoded scanlines is handled
+ * here.  We also handle writing the tag bit for the next
+ * scanline when doing 2d encoding.
+ */
+static void
+Fax3PutEOL(TIFF* tif)
+{
+	Fax3CodecState* sp = EncoderState(tif);
+	unsigned int bit = sp->bit;
+	int data = sp->data;
+	unsigned int code, length, tparm;
+
+	if (sp->b.groupoptions & GROUP3OPT_FILLBITS) {
+		/*
+		 * Force bit alignment so EOL will terminate on
+		 * a byte boundary.  That is, force the bit alignment
+		 * to 16-12 = 4 before putting out the EOL code.
+		 */
+		int align = 8 - 4;
+		if (align != sp->bit) {
+			if (align > sp->bit)
+				align = sp->bit + (8 - align);
+			else
+				align = sp->bit - align;
+			code = 0;
+			tparm=align; 
+			_PutBits(tif, 0, tparm);
+		}
+	}
+	code = EOL, length = 12;
+	if (is2DEncoding(sp))
+		code = (code<<1) | (sp->tag == G3_1D), length++;
+	_PutBits(tif, code, length);
+
+	sp->data = data;
+	sp->bit = bit;
+}
+
+/*
+ * Reset encoding state at the start of a strip.
+ */
+static int
+Fax3PreEncode(TIFF* tif, tsample_t s)
+{
+	Fax3CodecState* sp = EncoderState(tif);
+
+	(void) s;
+	assert(sp != NULL);
+	sp->bit = 8;
+	sp->data = 0;
+	sp->tag = G3_1D;
+	/*
+	 * This is necessary for Group 4; otherwise it isn't
+	 * needed because the first scanline of each strip ends
+	 * up being copied into the refline.
+	 */
+	if (sp->refline)
+		_TIFFmemset(sp->refline, 0x00, sp->b.rowbytes);
+	if (is2DEncoding(sp)) {
+		float res = tif->tif_dir.td_yresolution;
+		/*
+		 * The CCITT spec says that when doing 2d encoding, you
+		 * should only do it on K consecutive scanlines, where K
+		 * depends on the resolution of the image being encoded
+		 * (2 for <= 200 lpi, 4 for > 200 lpi).  Since the directory
+		 * code initializes td_yresolution to 0, this code will
+		 * select a K of 2 unless the YResolution tag is set
+		 * appropriately.  (Note also that we fudge a little here
+		 * and use 150 lpi to avoid problems with units conversion.)
+		 */
+		if (tif->tif_dir.td_resolutionunit == RESUNIT_CENTIMETER)
+			res *= 2.54f;		/* convert to inches */
+		sp->maxk = (res > 150 ? 4 : 2);
+		sp->k = sp->maxk-1;
+	} else
+		sp->k = sp->maxk = 0;
+	return (1);
+}
+
+static const unsigned char zeroruns[256] = {
+    8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,	/* 0x00 - 0x0f */
+    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,	/* 0x10 - 0x1f */
+    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0x20 - 0x2f */
+    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0x30 - 0x3f */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x40 - 0x4f */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x50 - 0x5f */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x60 - 0x6f */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x70 - 0x7f */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x80 - 0x8f */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x90 - 0x9f */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xa0 - 0xaf */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xb0 - 0xbf */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xc0 - 0xcf */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xd0 - 0xdf */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xe0 - 0xef */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xf0 - 0xff */
+};
+static const unsigned char oneruns[256] = {
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x00 - 0x0f */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x10 - 0x1f */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x20 - 0x2f */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x30 - 0x3f */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x40 - 0x4f */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x50 - 0x5f */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x60 - 0x6f */
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x70 - 0x7f */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x80 - 0x8f */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x90 - 0x9f */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0xa0 - 0xaf */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0xb0 - 0xbf */
+    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0xc0 - 0xcf */
+    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0xd0 - 0xdf */
+    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,	/* 0xe0 - 0xef */
+    4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 7, 8,	/* 0xf0 - 0xff */
+};
+
+/*
+ * On certain systems it pays to inline
+ * the routines that find pixel spans.
+ */
+#ifdef VAXC
+static	int32 find0span(unsigned char*, int32, int32);
+static	int32 find1span(unsigned char*, int32, int32);
+#pragma inline(find0span,find1span)
+#endif
+
+/*
+ * Find a span of ones or zeros using the supplied
+ * table.  The ``base'' of the bit string is supplied
+ * along with the start+end bit indices.
+ */
+inline static int32
+find0span(unsigned char* bp, int32 bs, int32 be)
+{
+	int32 bits = be - bs;
+	int32 n, span;
+
+	bp += bs>>3;
+	/*
+	 * Check partial byte on lhs.
+	 */
+	if (bits > 0 && (n = (bs & 7))) {
+		span = zeroruns[(*bp << n) & 0xff];
+		if (span > 8-n)		/* table value too generous */
+			span = 8-n;
+		if (span > bits)	/* constrain span to bit range */
+			span = bits;
+		if (n+span < 8)		/* doesn't extend to edge of byte */
+			return (span);
+		bits -= span;
+		bp++;
+	} else
+		span = 0;
+	if (bits >= (int32)(2 * 8 * sizeof(long))) {
+		long* lp;
+		/*
+		 * Align to longword boundary and check longwords.
+		 */
+		while (!isAligned(bp, long)) {
+			if (*bp != 0x00)
+				return (span + zeroruns[*bp]);
+			span += 8, bits -= 8;
+			bp++;
+		}
+		lp = (long*) bp;
+		while ((bits >= (int32)(8 * sizeof(long))) && (0 == *lp)) {
+			span += 8*sizeof (long), bits -= 8*sizeof (long);
+			lp++;
+		}
+		bp = (unsigned char*) lp;
+	}
+	/*
+	 * Scan full bytes for all 0's.
+	 */
+	while (bits >= 8) {
+		if (*bp != 0x00)	/* end of run */
+			return (span + zeroruns[*bp]);
+		span += 8, bits -= 8;
+		bp++;
+	}
+	/*
+	 * Check partial byte on rhs.
+	 */
+	if (bits > 0) {
+		n = zeroruns[*bp];
+		span += (n > bits ? bits : n);
+	}
+	return (span);
+}
+
+inline static int32
+find1span(unsigned char* bp, int32 bs, int32 be)
+{
+	int32 bits = be - bs;
+	int32 n, span;
+
+	bp += bs>>3;
+	/*
+	 * Check partial byte on lhs.
+	 */
+	if (bits > 0 && (n = (bs & 7))) {
+		span = oneruns[(*bp << n) & 0xff];
+		if (span > 8-n)		/* table value too generous */
+			span = 8-n;
+		if (span > bits)	/* constrain span to bit range */
+			span = bits;
+		if (n+span < 8)		/* doesn't extend to edge of byte */
+			return (span);
+		bits -= span;
+		bp++;
+	} else
+		span = 0;
+	if (bits >= (int32)(2 * 8 * sizeof(long))) {
+		long* lp;
+		/*
+		 * Align to longword boundary and check longwords.
+		 */
+		while (!isAligned(bp, long)) {
+			if (*bp != 0xff)
+				return (span + oneruns[*bp]);
+			span += 8, bits -= 8;
+			bp++;
+		}
+		lp = (long*) bp;
+		while ((bits >= (int32)(8 * sizeof(long))) && (~0 == *lp)) {
+			span += 8*sizeof (long), bits -= 8*sizeof (long);
+			lp++;
+		}
+		bp = (unsigned char*) lp;
+	}
+	/*
+	 * Scan full bytes for all 1's.
+	 */
+	while (bits >= 8) {
+		if (*bp != 0xff)	/* end of run */
+			return (span + oneruns[*bp]);
+		span += 8, bits -= 8;
+		bp++;
+	}
+	/*
+	 * Check partial byte on rhs.
+	 */
+	if (bits > 0) {
+		n = oneruns[*bp];
+		span += (n > bits ? bits : n);
+	}
+	return (span);
+}
+
+/*
+ * Return the offset of the next bit in the range
+ * [bs..be] that is different from the specified
+ * color.  The end, be, is returned if no such bit
+ * exists.
+ */
+#define	finddiff(_cp, _bs, _be, _color)	\
+	(_bs + (_color ? find1span(_cp,_bs,_be) : find0span(_cp,_bs,_be)))
+/*
+ * Like finddiff, but also check the starting bit
+ * against the end in case start > end.
+ */
+#define	finddiff2(_cp, _bs, _be, _color) \
+	(_bs < _be ? finddiff(_cp,_bs,_be,_color) : _be)
+
+/*
+ * 1d-encode a row of pixels.  The encoding is
+ * a sequence of all-white or all-black spans
+ * of pixels encoded with Huffman codes.
+ */
+static int
+Fax3Encode1DRow(TIFF* tif, unsigned char* bp, uint32 bits)
+{
+	Fax3CodecState* sp = EncoderState(tif);
+	int32 span;
+        uint32 bs = 0;
+
+	for (;;) {
+		span = find0span(bp, bs, bits);		/* white span */
+		putspan(tif, span, TIFFFaxWhiteCodes);
+		bs += span;
+		if (bs >= bits)
+			break;
+		span = find1span(bp, bs, bits);		/* black span */
+		putspan(tif, span, TIFFFaxBlackCodes);
+		bs += span;
+		if (bs >= bits)
+			break;
+	}
+	if (sp->b.mode & (FAXMODE_BYTEALIGN|FAXMODE_WORDALIGN)) {
+		if (sp->bit != 8)			/* byte-align */
+			Fax3FlushBits(tif, sp);
+		if ((sp->b.mode&FAXMODE_WORDALIGN) &&
+		    !isAligned(tif->tif_rawcp, uint16))
+			Fax3FlushBits(tif, sp);
+	}
+	return (1);
+}
+
+static const tableentry horizcode =
+    { 3, 0x1, 0 };	/* 001 */
+static const tableentry passcode =
+    { 4, 0x1, 0 };	/* 0001 */
+static const tableentry vcodes[7] = {
+    { 7, 0x03, 0 },	/* 0000 011 */
+    { 6, 0x03, 0 },	/* 0000 11 */
+    { 3, 0x03, 0 },	/* 011 */
+    { 1, 0x1, 0 },	/* 1 */
+    { 3, 0x2, 0 },	/* 010 */
+    { 6, 0x02, 0 },	/* 0000 10 */
+    { 7, 0x02, 0 }	/* 0000 010 */
+};
+
+/*
+ * 2d-encode a row of pixels.  Consult the CCITT
+ * documentation for the algorithm.
+ */
+static int
+Fax3Encode2DRow(TIFF* tif, unsigned char* bp, unsigned char* rp, uint32 bits)
+{
+#define	PIXEL(buf,ix)	((((buf)[(ix)>>3]) >> (7-((ix)&7))) & 1)
+        uint32 a0 = 0;
+	uint32 a1 = (PIXEL(bp, 0) != 0 ? 0 : finddiff(bp, 0, bits, 0));
+	uint32 b1 = (PIXEL(rp, 0) != 0 ? 0 : finddiff(rp, 0, bits, 0));
+	uint32 a2, b2;
+
+	for (;;) {
+		b2 = finddiff2(rp, b1, bits, PIXEL(rp,b1));
+		if (b2 >= a1) {
+			int32 d = b1 - a1;
+			if (!(-3 <= d && d <= 3)) {	/* horizontal mode */
+				a2 = finddiff2(bp, a1, bits, PIXEL(bp,a1));
+				putcode(tif, &horizcode);
+				if (a0+a1 == 0 || PIXEL(bp, a0) == 0) {
+					putspan(tif, a1-a0, TIFFFaxWhiteCodes);
+					putspan(tif, a2-a1, TIFFFaxBlackCodes);
+				} else {
+					putspan(tif, a1-a0, TIFFFaxBlackCodes);
+					putspan(tif, a2-a1, TIFFFaxWhiteCodes);
+				}
+				a0 = a2;
+			} else {			/* vertical mode */
+				putcode(tif, &vcodes[d+3]);
+				a0 = a1;
+			}
+		} else {				/* pass mode */
+			putcode(tif, &passcode);
+			a0 = b2;
+		}
+		if (a0 >= bits)
+			break;
+		a1 = finddiff(bp, a0, bits, PIXEL(bp,a0));
+		b1 = finddiff(rp, a0, bits, !PIXEL(bp,a0));
+		b1 = finddiff(rp, b1, bits, PIXEL(bp,a0));
+	}
+	return (1);
+#undef PIXEL
+}
+
+/*
+ * Encode a buffer of pixels.
+ */
+static int
+Fax3Encode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
+{
+	Fax3CodecState* sp = EncoderState(tif);
+
+	(void) s;
+	while ((long)cc > 0) {
+		if ((sp->b.mode & FAXMODE_NOEOL) == 0)
+			Fax3PutEOL(tif);
+		if (is2DEncoding(sp)) {
+			if (sp->tag == G3_1D) {
+				if (!Fax3Encode1DRow(tif, bp, sp->b.rowpixels))
+					return (0);
+				sp->tag = G3_2D;
+			} else {
+				if (!Fax3Encode2DRow(tif, bp, sp->refline,
+                                                     sp->b.rowpixels))
+					return (0);
+				sp->k--;
+			}
+			if (sp->k == 0) {
+				sp->tag = G3_1D;
+				sp->k = sp->maxk-1;
+			} else
+				_TIFFmemcpy(sp->refline, bp, sp->b.rowbytes);
+		} else {
+			if (!Fax3Encode1DRow(tif, bp, sp->b.rowpixels))
+				return (0);
+		}
+		bp += sp->b.rowbytes;
+		cc -= sp->b.rowbytes;
+	}
+	return (1);
+}
+
+static int
+Fax3PostEncode(TIFF* tif)
+{
+	Fax3CodecState* sp = EncoderState(tif);
+
+	if (sp->bit != 8)
+		Fax3FlushBits(tif, sp);
+	return (1);
+}
+
+static void
+Fax3Close(TIFF* tif)
+{
+	if ((Fax3State(tif)->mode & FAXMODE_NORTC) == 0) {
+		Fax3CodecState* sp = EncoderState(tif);
+		unsigned int code = EOL;
+		unsigned int length = 12;
+		int i;
+
+		if (is2DEncoding(sp))
+			code = (code<<1) | (sp->tag == G3_1D), length++;
+		for (i = 0; i < 6; i++)
+			Fax3PutBits(tif, code, length);
+		Fax3FlushBits(tif, sp);
+	}
+}
+
+static void
+Fax3Cleanup(TIFF* tif)
+{
+	Fax3CodecState* sp = DecoderState(tif);
+	
+	assert(sp != 0);
+
+	tif->tif_tagmethods.vgetfield = sp->b.vgetparent;
+	tif->tif_tagmethods.vsetfield = sp->b.vsetparent;
+
+	if (sp->runs)
+		_TIFFfree(sp->runs);
+	if (sp->refline)
+		_TIFFfree(sp->refline);
+
+	if (Fax3State(tif)->subaddress)
+		_TIFFfree(Fax3State(tif)->subaddress);
+	_TIFFfree(tif->tif_data);
+	tif->tif_data = NULL;
+
+	_TIFFSetDefaultCompressionState(tif);
+}
+
+#define	FIELD_BADFAXLINES	(FIELD_CODEC+0)
+#define	FIELD_CLEANFAXDATA	(FIELD_CODEC+1)
+#define	FIELD_BADFAXRUN		(FIELD_CODEC+2)
+#define	FIELD_RECVPARAMS	(FIELD_CODEC+3)
+#define	FIELD_SUBADDRESS	(FIELD_CODEC+4)
+#define	FIELD_RECVTIME		(FIELD_CODEC+5)
+#define	FIELD_FAXDCS		(FIELD_CODEC+6)
+
+#define	FIELD_OPTIONS		(FIELD_CODEC+7)
+
+static const TIFFFieldInfo faxFieldInfo[] = {
+    { TIFFTAG_FAXMODE,		 0, 0,	TIFF_ANY,	FIELD_PSEUDO,
+      FALSE,	FALSE,	"FaxMode" },
+    { TIFFTAG_FAXFILLFUNC,	 0, 0,	TIFF_ANY,	FIELD_PSEUDO,
+      FALSE,	FALSE,	"FaxFillFunc" },
+    { TIFFTAG_BADFAXLINES,	 1, 1,	TIFF_LONG,	FIELD_BADFAXLINES,
+      TRUE,	FALSE,	"BadFaxLines" },
+    { TIFFTAG_BADFAXLINES,	 1, 1,	TIFF_SHORT,	FIELD_BADFAXLINES,
+      TRUE,	FALSE,	"BadFaxLines" },
+    { TIFFTAG_CLEANFAXDATA,	 1, 1,	TIFF_SHORT,	FIELD_CLEANFAXDATA,
+      TRUE,	FALSE,	"CleanFaxData" },
+    { TIFFTAG_CONSECUTIVEBADFAXLINES,1,1, TIFF_LONG,	FIELD_BADFAXRUN,
+      TRUE,	FALSE,	"ConsecutiveBadFaxLines" },
+    { TIFFTAG_CONSECUTIVEBADFAXLINES,1,1, TIFF_SHORT,	FIELD_BADFAXRUN,
+      TRUE,	FALSE,	"ConsecutiveBadFaxLines" },
+    { TIFFTAG_FAXRECVPARAMS,	 1, 1, TIFF_LONG,	FIELD_RECVPARAMS,
+      TRUE,	FALSE,	"FaxRecvParams" },
+    { TIFFTAG_FAXSUBADDRESS,	-1,-1, TIFF_ASCII,	FIELD_SUBADDRESS,
+      TRUE,	FALSE,	"FaxSubAddress" },
+    { TIFFTAG_FAXRECVTIME,	 1, 1, TIFF_LONG,	FIELD_RECVTIME,
+      TRUE,	FALSE,	"FaxRecvTime" },
+    { TIFFTAG_FAXDCS,		-1,-1, TIFF_ASCII,	FIELD_FAXDCS,
+      TRUE,	FALSE,	"FaxDcs" },
+};
+static const TIFFFieldInfo fax3FieldInfo[] = {
+    { TIFFTAG_GROUP3OPTIONS,	 1, 1,	TIFF_LONG,	FIELD_OPTIONS,
+      FALSE,	FALSE,	"Group3Options" },
+};
+static const TIFFFieldInfo fax4FieldInfo[] = {
+    { TIFFTAG_GROUP4OPTIONS,	 1, 1,	TIFF_LONG,	FIELD_OPTIONS,
+      FALSE,	FALSE,	"Group4Options" },
+};
+#define	N(a)	(sizeof (a) / sizeof (a[0]))
+
+static int
+Fax3VSetField(TIFF* tif, ttag_t tag, va_list ap)
+{
+	Fax3BaseState* sp = Fax3State(tif);
+
+	assert(sp != 0);
+	assert(sp->vsetparent != 0);
+
+	switch (tag) {
+	case TIFFTAG_FAXMODE:
+		sp->mode = va_arg(ap, int);
+		return (1);			/* NB: pseudo tag */
+	case TIFFTAG_FAXFILLFUNC:
+		DecoderState(tif)->fill = va_arg(ap, TIFFFaxFillFunc);
+		return (1);			/* NB: pseudo tag */
+	case TIFFTAG_GROUP3OPTIONS:
+		/* XXX: avoid reading options if compression mismatches. */
+		if (tif->tif_dir.td_compression == COMPRESSION_CCITTFAX3)
+			sp->groupoptions = va_arg(ap, uint32);
+		break;
+	case TIFFTAG_GROUP4OPTIONS:
+		/* XXX: avoid reading options if compression mismatches. */
+		if (tif->tif_dir.td_compression == COMPRESSION_CCITTFAX4)
+			sp->groupoptions = va_arg(ap, uint32);
+		break;
+	case TIFFTAG_BADFAXLINES:
+		sp->badfaxlines = va_arg(ap, uint32);
+		break;
+	case TIFFTAG_CLEANFAXDATA:
+		sp->cleanfaxdata = (uint16) va_arg(ap, int);
+		break;
+	case TIFFTAG_CONSECUTIVEBADFAXLINES:
+		sp->badfaxrun = va_arg(ap, uint32);
+		break;
+	case TIFFTAG_FAXRECVPARAMS:
+		sp->recvparams = va_arg(ap, uint32);
+		break;
+	case TIFFTAG_FAXSUBADDRESS:
+		_TIFFsetString(&sp->subaddress, va_arg(ap, char*));
+		break;
+	case TIFFTAG_FAXRECVTIME:
+		sp->recvtime = va_arg(ap, uint32);
+		break;
+	case TIFFTAG_FAXDCS:
+		_TIFFsetString(&sp->faxdcs, va_arg(ap, char*));
+		break;
+	default:
+		return (*sp->vsetparent)(tif, tag, ap);
+	}
+	TIFFSetFieldBit(tif, _TIFFFieldWithTag(tif, tag)->field_bit);
+	tif->tif_flags |= TIFF_DIRTYDIRECT;
+	return (1);
+}
+
+static int
+Fax3VGetField(TIFF* tif, ttag_t tag, va_list ap)
+{
+	Fax3BaseState* sp = Fax3State(tif);
+
+	switch (tag) {
+	case TIFFTAG_FAXMODE:
+		*va_arg(ap, int*) = sp->mode;
+		break;
+	case TIFFTAG_FAXFILLFUNC:
+		*va_arg(ap, TIFFFaxFillFunc*) = DecoderState(tif)->fill;
+		break;
+	case TIFFTAG_GROUP3OPTIONS:
+	case TIFFTAG_GROUP4OPTIONS:
+		*va_arg(ap, uint32*) = sp->groupoptions;
+		break;
+	case TIFFTAG_BADFAXLINES:
+		*va_arg(ap, uint32*) = sp->badfaxlines;
+		break;
+	case TIFFTAG_CLEANFAXDATA:
+		*va_arg(ap, uint16*) = sp->cleanfaxdata;
+		break;
+	case TIFFTAG_CONSECUTIVEBADFAXLINES:
+		*va_arg(ap, uint32*) = sp->badfaxrun;
+		break;
+	case TIFFTAG_FAXRECVPARAMS:
+		*va_arg(ap, uint32*) = sp->recvparams;
+		break;
+	case TIFFTAG_FAXSUBADDRESS:
+		*va_arg(ap, char**) = sp->subaddress;
+		break;
+	case TIFFTAG_FAXRECVTIME:
+		*va_arg(ap, uint32*) = sp->recvtime;
+		break;
+	case TIFFTAG_FAXDCS:
+		*va_arg(ap, char**) = sp->faxdcs;
+		break;
+	default:
+		return (*sp->vgetparent)(tif, tag, ap);
+	}
+	return (1);
+}
+
+static void
+Fax3PrintDir(TIFF* tif, FILE* fd, long flags)
+{
+	Fax3BaseState* sp = Fax3State(tif);
+
+	(void) flags;
+	if (TIFFFieldSet(tif,FIELD_OPTIONS)) {
+		const char* sep = " ";
+		if (tif->tif_dir.td_compression == COMPRESSION_CCITTFAX4) {
+			fprintf(fd, "  Group 4 Options:");
+			if (sp->groupoptions & GROUP4OPT_UNCOMPRESSED)
+				fprintf(fd, "%suncompressed data", sep);
+		} else {
+
+			fprintf(fd, "  Group 3 Options:");
+			if (sp->groupoptions & GROUP3OPT_2DENCODING)
+				fprintf(fd, "%s2-d encoding", sep), sep = "+";
+			if (sp->groupoptions & GROUP3OPT_FILLBITS)
+				fprintf(fd, "%sEOL padding", sep), sep = "+";
+			if (sp->groupoptions & GROUP3OPT_UNCOMPRESSED)
+				fprintf(fd, "%suncompressed data", sep);
+		}
+		fprintf(fd, " (%lu = 0x%lx)\n",
+                        (unsigned long) sp->groupoptions,
+                        (unsigned long) sp->groupoptions);
+	}
+	if (TIFFFieldSet(tif,FIELD_CLEANFAXDATA)) {
+		fprintf(fd, "  Fax Data:");
+		switch (sp->cleanfaxdata) {
+		case CLEANFAXDATA_CLEAN:
+			fprintf(fd, " clean");
+			break;
+		case CLEANFAXDATA_REGENERATED:
+			fprintf(fd, " receiver regenerated");
+			break;
+		case CLEANFAXDATA_UNCLEAN:
+			fprintf(fd, " uncorrected errors");
+			break;
+		}
+		fprintf(fd, " (%u = 0x%x)\n",
+		    sp->cleanfaxdata, sp->cleanfaxdata);
+	}
+	if (TIFFFieldSet(tif,FIELD_BADFAXLINES))
+		fprintf(fd, "  Bad Fax Lines: %lu\n",
+                        (unsigned long) sp->badfaxlines);
+	if (TIFFFieldSet(tif,FIELD_BADFAXRUN))
+		fprintf(fd, "  Consecutive Bad Fax Lines: %lu\n",
+		    (unsigned long) sp->badfaxrun);
+	if (TIFFFieldSet(tif,FIELD_RECVPARAMS))
+		fprintf(fd, "  Fax Receive Parameters: %08lx\n",
+		   (unsigned long) sp->recvparams);
+	if (TIFFFieldSet(tif,FIELD_SUBADDRESS))
+		fprintf(fd, "  Fax SubAddress: %s\n", sp->subaddress);
+	if (TIFFFieldSet(tif,FIELD_RECVTIME))
+		fprintf(fd, "  Fax Receive Time: %lu secs\n",
+		    (unsigned long) sp->recvtime);
+	if (TIFFFieldSet(tif,FIELD_FAXDCS))
+		fprintf(fd, "  Fax DCS: %s\n", sp->faxdcs);
+}
+
+static int
+InitCCITTFax3(TIFF* tif)
+{
+	Fax3BaseState* sp;
+
+	/*
+	 * Allocate state block so tag methods have storage to record values.
+	 */
+	tif->tif_data = (tidata_t)
+		_TIFFmalloc(sizeof (Fax3CodecState));
+
+	if (tif->tif_data == NULL) {
+		TIFFErrorExt(tif->tif_clientdata, "TIFFInitCCITTFax3",
+		    "%s: No space for state block", tif->tif_name);
+		return (0);
+	}
+
+	sp = Fax3State(tif);
+        sp->rw_mode = tif->tif_mode;
+
+	/*
+	 * Merge codec-specific tag information and
+	 * override parent get/set field methods.
+	 */
+	_TIFFMergeFieldInfo(tif, faxFieldInfo, N(faxFieldInfo));
+	sp->vgetparent = tif->tif_tagmethods.vgetfield;
+	tif->tif_tagmethods.vgetfield = Fax3VGetField; /* hook for codec tags */
+	sp->vsetparent = tif->tif_tagmethods.vsetfield;
+	tif->tif_tagmethods.vsetfield = Fax3VSetField; /* hook for codec tags */
+	tif->tif_tagmethods.printdir = Fax3PrintDir;   /* hook for codec tags */
+	sp->groupoptions = 0;	
+	sp->recvparams = 0;
+	sp->subaddress = NULL;
+	sp->faxdcs = NULL;
+
+	if (sp->rw_mode == O_RDONLY) /* FIXME: improve for in place update */
+		tif->tif_flags |= TIFF_NOBITREV; /* decoder does bit reversal */
+	DecoderState(tif)->runs = NULL;
+	TIFFSetField(tif, TIFFTAG_FAXFILLFUNC, _TIFFFax3fillruns);
+	EncoderState(tif)->refline = NULL;
+
+	/*
+	 * Install codec methods.
+	 */
+	tif->tif_setupdecode = Fax3SetupState;
+	tif->tif_predecode = Fax3PreDecode;
+	tif->tif_decoderow = Fax3Decode1D;
+	tif->tif_decodestrip = Fax3Decode1D;
+	tif->tif_decodetile = Fax3Decode1D;
+	tif->tif_setupencode = Fax3SetupState;
+	tif->tif_preencode = Fax3PreEncode;
+	tif->tif_postencode = Fax3PostEncode;
+	tif->tif_encoderow = Fax3Encode;
+	tif->tif_encodestrip = Fax3Encode;
+	tif->tif_encodetile = Fax3Encode;
+	tif->tif_close = Fax3Close;
+	tif->tif_cleanup = Fax3Cleanup;
+
+	return (1);
+}
+
+int
+TIFFInitCCITTFax3(TIFF* tif, int scheme)
+{
+	(void) scheme;
+	if (InitCCITTFax3(tif)) {
+		_TIFFMergeFieldInfo(tif, fax3FieldInfo, N(fax3FieldInfo));
+
+		/*
+		 * The default format is Class/F-style w/o RTC.
+		 */
+		return TIFFSetField(tif, TIFFTAG_FAXMODE, FAXMODE_CLASSF);
+	} else
+		return (0);
+}
+
+/*
+ * CCITT Group 4 (T.6) Facsimile-compatible
+ * Compression Scheme Support.
+ */
+
+#define	SWAP(t,a,b)	{ t x; x = (a); (a) = (b); (b) = x; }
+/*
+ * Decode the requested amount of G4-encoded data.
+ */
+static int
+Fax4Decode(TIFF* tif, tidata_t buf, tsize_t occ, tsample_t s)
+{
+	DECLARE_STATE_2D(tif, sp, "Fax4Decode");
+        int line = 0;
+
+	(void) s;
+	CACHE_STATE(tif, sp);
+	while ((long)occ > 0) {
+		a0 = 0;
+		RunLength = 0;
+		pa = thisrun = sp->curruns;
+		pb = sp->refruns;
+		b1 = *pb++;
+#ifdef FAX3_DEBUG
+		printf("\nBitAcc=%08X, BitsAvail = %d\n", BitAcc, BitsAvail);
+		printf("-------------------- %d\n", tif->tif_row);
+		fflush(stdout);
+#endif
+		EXPAND2D(EOFG4);
+                if (EOLcnt)
+                    goto EOFG4;
+		(*sp->fill)(buf, thisrun, pa, lastx);
+		SETVALUE(0);		/* imaginary change for reference */
+		SWAP(uint32*, sp->curruns, sp->refruns);
+		buf += sp->b.rowbytes;
+		occ -= sp->b.rowbytes;
+                line++;
+		continue;
+	EOFG4:
+                NeedBits16( 13, BADG4 );
+        BADG4:
+#ifdef FAX3_DEBUG
+                if( GetBits(13) != 0x1001 )
+                    fputs( "Bad RTC\n", stderr );
+#endif                
+                ClrBits( 13 );
+		(*sp->fill)(buf, thisrun, pa, lastx);
+		UNCACHE_STATE(tif, sp);
+		return (-1);
+	}
+	UNCACHE_STATE(tif, sp);
+	return (1);
+}
+#undef	SWAP
+
+/*
+ * Encode the requested amount of data.
+ */
+static int
+Fax4Encode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
+{
+	Fax3CodecState *sp = EncoderState(tif);
+
+	(void) s;
+	while ((long)cc > 0) {
+		if (!Fax3Encode2DRow(tif, bp, sp->refline, sp->b.rowpixels))
+			return (0);
+		_TIFFmemcpy(sp->refline, bp, sp->b.rowbytes);
+		bp += sp->b.rowbytes;
+		cc -= sp->b.rowbytes;
+	}
+	return (1);
+}
+
+static int
+Fax4PostEncode(TIFF* tif)
+{
+	Fax3CodecState *sp = EncoderState(tif);
+
+	/* terminate strip w/ EOFB */
+	Fax3PutBits(tif, EOL, 12);
+	Fax3PutBits(tif, EOL, 12);
+	if (sp->bit != 8)
+		Fax3FlushBits(tif, sp);
+	return (1);
+}
+
+int
+TIFFInitCCITTFax4(TIFF* tif, int scheme)
+{
+	(void) scheme;
+	if (InitCCITTFax3(tif)) {		/* reuse G3 support */
+		_TIFFMergeFieldInfo(tif, fax4FieldInfo, N(fax4FieldInfo));
+
+		tif->tif_decoderow = Fax4Decode;
+		tif->tif_decodestrip = Fax4Decode;
+		tif->tif_decodetile = Fax4Decode;
+		tif->tif_encoderow = Fax4Encode;
+		tif->tif_encodestrip = Fax4Encode;
+		tif->tif_encodetile = Fax4Encode;
+		tif->tif_postencode = Fax4PostEncode;
+		/*
+		 * Suppress RTC at the end of each strip.
+		 */
+		return TIFFSetField(tif, TIFFTAG_FAXMODE, FAXMODE_NORTC);
+	} else
+		return (0);
+}
+
+/*
+ * CCITT Group 3 1-D Modified Huffman RLE Compression Support.
+ * (Compression algorithms 2 and 32771)
+ */
+
+/*
+ * Decode the requested amount of RLE-encoded data.
+ */
+static int
+Fax3DecodeRLE(TIFF* tif, tidata_t buf, tsize_t occ, tsample_t s)
+{
+	DECLARE_STATE(tif, sp, "Fax3DecodeRLE");
+	int mode = sp->b.mode;
+        int line = 0;
+
+	(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
+		EXPAND1D(EOFRLE);
+		(*sp->fill)(buf, thisrun, pa, lastx);
+		/*
+		 * Cleanup at the end of the row.
+		 */
+		if (mode & FAXMODE_BYTEALIGN) {
+			int n = BitsAvail - (BitsAvail &~ 7);
+			ClrBits(n);
+		} else if (mode & FAXMODE_WORDALIGN) {
+			int n = BitsAvail - (BitsAvail &~ 15);
+			ClrBits(n);
+			if (BitsAvail == 0 && !isAligned(cp, uint16))
+			    cp++;
+		}
+		buf += sp->b.rowbytes;
+		occ -= sp->b.rowbytes;
+                line++;
+		continue;
+	EOFRLE:				/* premature EOF */
+		(*sp->fill)(buf, thisrun, pa, lastx);
+		UNCACHE_STATE(tif, sp);
+		return (-1);
+	}
+	UNCACHE_STATE(tif, sp);
+	return (1);
+}
+
+int
+TIFFInitCCITTRLE(TIFF* tif, int scheme)
+{
+	(void) scheme;
+	if (InitCCITTFax3(tif)) {		/* reuse G3 support */
+		tif->tif_decoderow = Fax3DecodeRLE;
+		tif->tif_decodestrip = Fax3DecodeRLE;
+		tif->tif_decodetile = Fax3DecodeRLE;
+		/*
+		 * Suppress RTC+EOLs when encoding and byte-align data.
+		 */
+		return TIFFSetField(tif, TIFFTAG_FAXMODE,
+		    FAXMODE_NORTC|FAXMODE_NOEOL|FAXMODE_BYTEALIGN);
+	} else
+		return (0);
+}
+
+int
+TIFFInitCCITTRLEW(TIFF* tif, int scheme)
+{
+	(void) scheme;
+	if (InitCCITTFax3(tif)) {		/* reuse G3 support */
+		tif->tif_decoderow = Fax3DecodeRLE;
+		tif->tif_decodestrip = Fax3DecodeRLE;
+		tif->tif_decodetile = Fax3DecodeRLE;
+		/*
+		 * Suppress RTC+EOLs when encoding and word-align data.
+		 */
+		return TIFFSetField(tif, TIFFTAG_FAXMODE,
+		    FAXMODE_NORTC|FAXMODE_NOEOL|FAXMODE_WORDALIGN);
+	} else
+		return (0);
+}
+#endif /* CCITT_SUPPORT */
+
+/* vim: set ts=8 sts=8 sw=8 noet: */