1/* $Id: tif_fax3.c,v 1.43.2.10 2010-06-09 17:16:58 bfriesen Exp $ */
2
3/*
4 * Copyright (c) 1990-1997 Sam Leffler
5 * Copyright (c) 1991-1997 Silicon Graphics, Inc.
6 *
7 * Permission to use, copy, modify, distribute, and sell this software and
8 * its documentation for any purpose is hereby granted without fee, provided
9 * that (i) the above copyright notices and this permission notice appear in
10 * all copies of the software and related documentation, and (ii) the names of
11 * Sam Leffler and Silicon Graphics may not be used in any advertising or
12 * publicity relating to the software without the specific, prior written
13 * permission of Sam Leffler and Silicon Graphics.
14 *
15 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
17 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
18 *
19 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
20 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
21 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
22 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
23 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
24 * OF THIS SOFTWARE.
25 */
26
27#include "tiffiop.h"
28#ifdef CCITT_SUPPORT
29/*
30 * TIFF Library.
31 *
32 * CCITT Group 3 (T.4) and Group 4 (T.6) Compression Support.
33 *
34 * This file contains support for decoding and encoding TIFF
35 * compression algorithms 2, 3, 4, and 32771.
36 *
37 * Decoder support is derived, with permission, from the code
38 * in Frank Cringle's viewfax program;
39 *      Copyright (C) 1990, 1995  Frank D. Cringle.
40 */
41#include "tif_fax3.h"
42#define	G3CODES
43#include "t4.h"
44#include <stdio.h>
45
46/*
47 * Compression+decompression state blocks are
48 * derived from this ``base state'' block.
49 */
50typedef struct {
51        int     rw_mode;                /* O_RDONLY for decode, else encode */
52	int	mode;			/* operating mode */
53	uint32	rowbytes;		/* bytes in a decoded scanline */
54	uint32	rowpixels;		/* pixels in a scanline */
55
56	uint16	cleanfaxdata;		/* CleanFaxData tag */
57	uint32	badfaxrun;		/* BadFaxRun tag */
58	uint32	badfaxlines;		/* BadFaxLines tag */
59	uint32	groupoptions;		/* Group 3/4 options tag */
60	uint32	recvparams;		/* encoded Class 2 session params */
61	char*	subaddress;		/* subaddress string */
62	uint32	recvtime;		/* time spent receiving (secs) */
63	char*	faxdcs;			/* Table 2/T.30 encoded session params */
64	TIFFVGetMethod vgetparent;	/* super-class method */
65	TIFFVSetMethod vsetparent;	/* super-class method */
66	TIFFPrintMethod printdir;	/* super-class method */
67} Fax3BaseState;
68#define	Fax3State(tif)		((Fax3BaseState*) (tif)->tif_data)
69
70typedef enum { G3_1D, G3_2D } Ttag;
71typedef struct {
72	Fax3BaseState b;
73
74	/* Decoder state info */
75	const unsigned char* bitmap;	/* bit reversal table */
76	uint32	data;			/* current i/o byte/word */
77	int	bit;			/* current i/o bit in byte */
78	int	EOLcnt;			/* count of EOL codes recognized */
79	TIFFFaxFillFunc fill;		/* fill routine */
80	uint32*	runs;			/* b&w runs for current/previous row */
81	uint32*	refruns;		/* runs for reference line */
82	uint32*	curruns;		/* runs for current line */
83
84	/* Encoder state info */
85	Ttag    tag;			/* encoding state */
86	unsigned char*	refline;	/* reference line for 2d decoding */
87	int	k;			/* #rows left that can be 2d encoded */
88	int	maxk;			/* max #rows that can be 2d encoded */
89
90	int line;
91} Fax3CodecState;
92#define	DecoderState(tif)	((Fax3CodecState*) Fax3State(tif))
93#define	EncoderState(tif)	((Fax3CodecState*) Fax3State(tif))
94
95#define	is2DEncoding(sp) \
96	(sp->b.groupoptions & GROUP3OPT_2DENCODING)
97#define	isAligned(p,t)	((((unsigned long)(p)) & (sizeof (t)-1)) == 0)
98
99/*
100 * Group 3 and Group 4 Decoding.
101 */
102
103/*
104 * These macros glue the TIFF library state to
105 * the state expected by Frank's decoder.
106 */
107#define	DECLARE_STATE(tif, sp, mod)					\
108    static const char module[] = mod;					\
109    Fax3CodecState* sp = DecoderState(tif);				\
110    int a0;				/* reference element */		\
111    int lastx = sp->b.rowpixels;	/* last element in row */	\
112    uint32 BitAcc;			/* bit accumulator */		\
113    int BitsAvail;			/* # valid bits in BitAcc */	\
114    int RunLength;			/* length of current run */	\
115    unsigned char* cp;			/* next byte of input data */	\
116    unsigned char* ep;			/* end of input data */		\
117    uint32* pa;				/* place to stuff next run */	\
118    uint32* thisrun;			/* current row's run array */	\
119    int EOLcnt;				/* # EOL codes recognized */	\
120    const unsigned char* bitmap = sp->bitmap;	/* input data bit reverser */	\
121    const TIFFFaxTabEnt* TabEnt
122#define	DECLARE_STATE_2D(tif, sp, mod)					\
123    DECLARE_STATE(tif, sp, mod);					\
124    int b1;				/* next change on prev line */	\
125    uint32* pb				/* next run in reference line */\
126/*
127 * Load any state that may be changed during decoding.
128 */
129#define	CACHE_STATE(tif, sp) do {					\
130    BitAcc = sp->data;							\
131    BitsAvail = sp->bit;						\
132    EOLcnt = sp->EOLcnt;						\
133    cp = (unsigned char*) tif->tif_rawcp;				\
134    ep = cp + tif->tif_rawcc;						\
135} while (0)
136/*
137 * Save state possibly changed during decoding.
138 */
139#define	UNCACHE_STATE(tif, sp) do {					\
140    sp->bit = BitsAvail;						\
141    sp->data = BitAcc;							\
142    sp->EOLcnt = EOLcnt;						\
143    tif->tif_rawcc -= (tidata_t) cp - tif->tif_rawcp;			\
144    tif->tif_rawcp = (tidata_t) cp;					\
145} while (0)
146
147/*
148 * Setup state for decoding a strip.
149 */
150static int
151Fax3PreDecode(TIFF* tif, tsample_t s)
152{
153	Fax3CodecState* sp = DecoderState(tif);
154
155	(void) s;
156	assert(sp != NULL);
157	sp->bit = 0;			/* force initial read */
158	sp->data = 0;
159	sp->EOLcnt = 0;			/* force initial scan for EOL */
160	/*
161	 * Decoder assumes lsb-to-msb bit order.  Note that we select
162	 * this here rather than in Fax3SetupState so that viewers can
163	 * hold the image open, fiddle with the FillOrder tag value,
164	 * and then re-decode the image.  Otherwise they'd need to close
165	 * and open the image to get the state reset.
166	 */
167	sp->bitmap =
168	    TIFFGetBitRevTable(tif->tif_dir.td_fillorder != FILLORDER_LSB2MSB);
169	if (sp->refruns) {		/* init reference line to white */
170		sp->refruns[0] = (uint32) sp->b.rowpixels;
171		sp->refruns[1] = 0;
172	}
173	sp->line = 0;
174	return (1);
175}
176
177/*
178 * Routine for handling various errors/conditions.
179 * Note how they are "glued into the decoder" by
180 * overriding the definitions used by the decoder.
181 */
182
183static void
184Fax3Unexpected(const char* module, TIFF* tif, uint32 line, uint32 a0)
185{
186	TIFFErrorExt(tif->tif_clientdata, module, "%s: Bad code word at line %u of %s %u (x %u)",
187		     tif->tif_name, line, isTiled(tif) ? "tile" : "strip",
188		     (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip),
189		     a0);
190}
191#define	unexpected(table, a0)	Fax3Unexpected(module, tif, sp->line, a0)
192
193static void
194Fax3Extension(const char* module, TIFF* tif, uint32 line, uint32 a0)
195{
196	TIFFErrorExt(tif->tif_clientdata, module,
197		     "%s: Uncompressed data (not supported) at line %u of %s %u (x %u)",
198		     tif->tif_name, line, isTiled(tif) ? "tile" : "strip",
199		     (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip),
200		     a0);
201}
202#define	extension(a0)	Fax3Extension(module, tif, sp->line, a0)
203
204static void
205Fax3BadLength(const char* module, TIFF* tif, uint32 line, uint32 a0, uint32 lastx)
206{
207	TIFFWarningExt(tif->tif_clientdata, module, "%s: %s at line %u of %s %u (got %u, expected %u)",
208		       tif->tif_name,
209		       a0 < lastx ? "Premature EOL" : "Line length mismatch",
210		       line, isTiled(tif) ? "tile" : "strip",
211		       (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip),
212		       a0, lastx);
213}
214#define	badlength(a0,lastx)	Fax3BadLength(module, tif, sp->line, a0, lastx)
215
216static void
217Fax3PrematureEOF(const char* module, TIFF* tif, uint32 line, uint32 a0)
218{
219	TIFFWarningExt(tif->tif_clientdata, module, "%s: Premature EOF at line %u of %s %u (x %u)",
220	    tif->tif_name,
221		       line, isTiled(tif) ? "tile" : "strip",
222		       (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip),
223		       a0);
224}
225#define	prematureEOF(a0)	Fax3PrematureEOF(module, tif, sp->line, a0)
226
227#define	Nop
228
229/*
230 * Decode the requested amount of G3 1D-encoded data.
231 */
232static int
233Fax3Decode1D(TIFF* tif, tidata_t buf, tsize_t occ, tsample_t s)
234{
235	DECLARE_STATE(tif, sp, "Fax3Decode1D");
236
237	(void) s;
238	CACHE_STATE(tif, sp);
239	thisrun = sp->curruns;
240	while ((long)occ > 0) {
241		a0 = 0;
242		RunLength = 0;
243		pa = thisrun;
244#ifdef FAX3_DEBUG
245		printf("\nBitAcc=%08X, BitsAvail = %d\n", BitAcc, BitsAvail);
246		printf("-------------------- %d\n", tif->tif_row);
247		fflush(stdout);
248#endif
249		SYNC_EOL(EOF1D);
250		EXPAND1D(EOF1Da);
251		(*sp->fill)(buf, thisrun, pa, lastx);
252		buf += sp->b.rowbytes;
253		occ -= sp->b.rowbytes;
254		sp->line++;
255		continue;
256	EOF1D:				/* premature EOF */
257		CLEANUP_RUNS();
258	EOF1Da:				/* premature EOF */
259		(*sp->fill)(buf, thisrun, pa, lastx);
260		UNCACHE_STATE(tif, sp);
261		return (-1);
262	}
263	UNCACHE_STATE(tif, sp);
264	return (1);
265}
266
267#define	SWAP(t,a,b)	{ t x; x = (a); (a) = (b); (b) = x; }
268/*
269 * Decode the requested amount of G3 2D-encoded data.
270 */
271static int
272Fax3Decode2D(TIFF* tif, tidata_t buf, tsize_t occ, tsample_t s)
273{
274	DECLARE_STATE_2D(tif, sp, "Fax3Decode2D");
275	int is1D;			/* current line is 1d/2d-encoded */
276
277	(void) s;
278	CACHE_STATE(tif, sp);
279	while ((long)occ > 0) {
280		a0 = 0;
281		RunLength = 0;
282		pa = thisrun = sp->curruns;
283#ifdef FAX3_DEBUG
284		printf("\nBitAcc=%08X, BitsAvail = %d EOLcnt = %d",
285		    BitAcc, BitsAvail, EOLcnt);
286#endif
287		SYNC_EOL(EOF2D);
288		NeedBits8(1, EOF2D);
289		is1D = GetBits(1);	/* 1D/2D-encoding tag bit */
290		ClrBits(1);
291#ifdef FAX3_DEBUG
292		printf(" %s\n-------------------- %d\n",
293		    is1D ? "1D" : "2D", tif->tif_row);
294		fflush(stdout);
295#endif
296		pb = sp->refruns;
297		b1 = *pb++;
298		if (is1D)
299			EXPAND1D(EOF2Da);
300		else
301			EXPAND2D(EOF2Da);
302		(*sp->fill)(buf, thisrun, pa, lastx);
303		SETVALUE(0);		/* imaginary change for reference */
304		SWAP(uint32*, sp->curruns, sp->refruns);
305		buf += sp->b.rowbytes;
306		occ -= sp->b.rowbytes;
307		sp->line++;
308		continue;
309	EOF2D:				/* premature EOF */
310		CLEANUP_RUNS();
311	EOF2Da:				/* premature EOF */
312		(*sp->fill)(buf, thisrun, pa, lastx);
313		UNCACHE_STATE(tif, sp);
314		return (-1);
315	}
316	UNCACHE_STATE(tif, sp);
317	return (1);
318}
319#undef SWAP
320
321/*
322 * The ZERO & FILL macros must handle spans < 2*sizeof(long) bytes.
323 * For machines with 64-bit longs this is <16 bytes; otherwise
324 * this is <8 bytes.  We optimize the code here to reflect the
325 * machine characteristics.
326 */
327#if SIZEOF_LONG == 8
328# define FILL(n, cp)							    \
329    switch (n) {							    \
330    case 15:(cp)[14] = 0xff; case 14:(cp)[13] = 0xff; case 13: (cp)[12] = 0xff;\
331    case 12:(cp)[11] = 0xff; case 11:(cp)[10] = 0xff; case 10: (cp)[9] = 0xff;\
332    case  9: (cp)[8] = 0xff; case  8: (cp)[7] = 0xff; case  7: (cp)[6] = 0xff;\
333    case  6: (cp)[5] = 0xff; case  5: (cp)[4] = 0xff; case  4: (cp)[3] = 0xff;\
334    case  3: (cp)[2] = 0xff; case  2: (cp)[1] = 0xff;			      \
335    case  1: (cp)[0] = 0xff; (cp) += (n); case 0:  ;			      \
336    }
337# define ZERO(n, cp)							\
338    switch (n) {							\
339    case 15:(cp)[14] = 0; case 14:(cp)[13] = 0; case 13: (cp)[12] = 0;	\
340    case 12:(cp)[11] = 0; case 11:(cp)[10] = 0; case 10: (cp)[9] = 0;	\
341    case  9: (cp)[8] = 0; case  8: (cp)[7] = 0; case  7: (cp)[6] = 0;	\
342    case  6: (cp)[5] = 0; case  5: (cp)[4] = 0; case  4: (cp)[3] = 0;	\
343    case  3: (cp)[2] = 0; case  2: (cp)[1] = 0;				\
344    case  1: (cp)[0] = 0; (cp) += (n); case 0:  ;			\
345    }
346#else
347# define FILL(n, cp)							    \
348    switch (n) {							    \
349    case 7: (cp)[6] = 0xff; case 6: (cp)[5] = 0xff; case 5: (cp)[4] = 0xff; \
350    case 4: (cp)[3] = 0xff; case 3: (cp)[2] = 0xff; case 2: (cp)[1] = 0xff; \
351    case 1: (cp)[0] = 0xff; (cp) += (n); case 0:  ;			    \
352    }
353# define ZERO(n, cp)							\
354    switch (n) {							\
355    case 7: (cp)[6] = 0; case 6: (cp)[5] = 0; case 5: (cp)[4] = 0;	\
356    case 4: (cp)[3] = 0; case 3: (cp)[2] = 0; case 2: (cp)[1] = 0;	\
357    case 1: (cp)[0] = 0; (cp) += (n); case 0:  ;			\
358    }
359#endif
360
361/*
362 * Bit-fill a row according to the white/black
363 * runs generated during G3/G4 decoding.
364 */
365void
366_TIFFFax3fillruns(unsigned char* buf, uint32* runs, uint32* erun, uint32 lastx)
367{
368	static const unsigned char _fillmasks[] =
369	    { 0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff };
370	unsigned char* cp;
371	uint32 x, bx, run;
372	int32 n, nw;
373	long* lp;
374
375	if ((erun-runs)&1)
376	    *erun++ = 0;
377	x = 0;
378	for (; runs < erun; runs += 2) {
379	    run = runs[0];
380	    if (x+run > lastx || run > lastx )
381		run = runs[0] = (uint32) (lastx - x);
382	    if (run) {
383		cp = buf + (x>>3);
384		bx = x&7;
385		if (run > 8-bx) {
386		    if (bx) {			/* align to byte boundary */
387			*cp++ &= 0xff << (8-bx);
388			run -= 8-bx;
389		    }
390		    if( (n = run >> 3) != 0 ) {	/* multiple bytes to fill */
391			if ((n/sizeof (long)) > 1) {
392			    /*
393			     * Align to longword boundary and fill.
394			     */
395			    for (; n && !isAligned(cp, long); n--)
396				    *cp++ = 0x00;
397			    lp = (long*) cp;
398			    nw = (int32)(n / sizeof (long));
399			    n -= nw * sizeof (long);
400			    do {
401				    *lp++ = 0L;
402			    } while (--nw);
403			    cp = (unsigned char*) lp;
404			}
405			ZERO(n, cp);
406			run &= 7;
407		    }
408		    if (run)
409			cp[0] &= 0xff >> run;
410		} else
411		    cp[0] &= ~(_fillmasks[run]>>bx);
412		x += runs[0];
413	    }
414	    run = runs[1];
415	    if (x+run > lastx || run > lastx )
416		run = runs[1] = lastx - x;
417	    if (run) {
418		cp = buf + (x>>3);
419		bx = x&7;
420		if (run > 8-bx) {
421		    if (bx) {			/* align to byte boundary */
422			*cp++ |= 0xff >> bx;
423			run -= 8-bx;
424		    }
425		    if( (n = run>>3) != 0 ) {	/* multiple bytes to fill */
426			if ((n/sizeof (long)) > 1) {
427			    /*
428			     * Align to longword boundary and fill.
429			     */
430			    for (; n && !isAligned(cp, long); n--)
431				*cp++ = 0xff;
432			    lp = (long*) cp;
433			    nw = (int32)(n / sizeof (long));
434			    n -= nw * sizeof (long);
435			    do {
436				*lp++ = -1L;
437			    } while (--nw);
438			    cp = (unsigned char*) lp;
439			}
440			FILL(n, cp);
441			run &= 7;
442		    }
443		    if (run)
444			cp[0] |= 0xff00 >> run;
445		} else
446		    cp[0] |= _fillmasks[run]>>bx;
447		x += runs[1];
448	    }
449	}
450	assert(x == lastx);
451}
452#undef	ZERO
453#undef	FILL
454
455/*
456 * Setup G3/G4-related compression/decompression state
457 * before data is processed.  This routine is called once
458 * per image -- it sets up different state based on whether
459 * or not decoding or encoding is being done and whether
460 * 1D- or 2D-encoded data is involved.
461 */
462static int
463Fax3SetupState(TIFF* tif)
464{
465	TIFFDirectory* td = &tif->tif_dir;
466	Fax3BaseState* sp = Fax3State(tif);
467	int needsRefLine;
468	Fax3CodecState* dsp = (Fax3CodecState*) Fax3State(tif);
469	uint32 rowbytes, rowpixels, nruns;
470
471	if (td->td_bitspersample != 1) {
472		TIFFErrorExt(tif->tif_clientdata, tif->tif_name,
473		    "Bits/sample must be 1 for Group 3/4 encoding/decoding");
474		return (0);
475	}
476	/*
477	 * Calculate the scanline/tile widths.
478	 */
479	if (isTiled(tif)) {
480		rowbytes = TIFFTileRowSize(tif);
481		rowpixels = td->td_tilewidth;
482	} else {
483		rowbytes = TIFFScanlineSize(tif);
484		rowpixels = td->td_imagewidth;
485	}
486	sp->rowbytes = (uint32) rowbytes;
487	sp->rowpixels = (uint32) rowpixels;
488	/*
489	 * Allocate any additional space required for decoding/encoding.
490	 */
491	needsRefLine = (
492	    (sp->groupoptions & GROUP3OPT_2DENCODING) ||
493	    td->td_compression == COMPRESSION_CCITTFAX4
494	);
495
496	/*
497	  Assure that allocation computations do not overflow.
498
499	  TIFFroundup and TIFFSafeMultiply return zero on integer overflow
500	*/
501	dsp->runs=(uint32*) NULL;
502	nruns = TIFFroundup(rowpixels,32);
503	if (needsRefLine) {
504		nruns = TIFFSafeMultiply(uint32,nruns,2);
505	}
506	if ((nruns == 0) || (TIFFSafeMultiply(uint32,nruns,2) == 0)) {
507		TIFFErrorExt(tif->tif_clientdata, tif->tif_name,
508			     "Row pixels integer overflow (rowpixels %u)",
509			     rowpixels);
510		return (0);
511	}
512	dsp->runs = (uint32*) _TIFFCheckMalloc(tif,
513					       TIFFSafeMultiply(uint32,nruns,2),
514					       sizeof (uint32),
515					       "for Group 3/4 run arrays");
516	if (dsp->runs == NULL)
517		return (0);
518	dsp->curruns = dsp->runs;
519	if (needsRefLine)
520		dsp->refruns = dsp->runs + nruns;
521	else
522		dsp->refruns = NULL;
523	if (td->td_compression == COMPRESSION_CCITTFAX3
524	    && is2DEncoding(dsp)) {	/* NB: default is 1D routine */
525		tif->tif_decoderow = Fax3Decode2D;
526		tif->tif_decodestrip = Fax3Decode2D;
527		tif->tif_decodetile = Fax3Decode2D;
528	}
529
530	if (needsRefLine) {		/* 2d encoding */
531		Fax3CodecState* esp = EncoderState(tif);
532		/*
533		 * 2d encoding requires a scanline
534		 * buffer for the ``reference line''; the
535		 * scanline against which delta encoding
536		 * is referenced.  The reference line must
537		 * be initialized to be ``white'' (done elsewhere).
538		 */
539		esp->refline = (unsigned char*) _TIFFmalloc(rowbytes);
540		if (esp->refline == NULL) {
541			TIFFErrorExt(tif->tif_clientdata, "Fax3SetupState",
542			    "%s: No space for Group 3/4 reference line",
543			    tif->tif_name);
544			return (0);
545		}
546	} else					/* 1d encoding */
547		EncoderState(tif)->refline = NULL;
548
549	return (1);
550}
551
552/*
553 * CCITT Group 3 FAX Encoding.
554 */
555
556#define	Fax3FlushBits(tif, sp) {				\
557	if ((tif)->tif_rawcc >= (tif)->tif_rawdatasize)		\
558		(void) TIFFFlushData1(tif);			\
559	*(tif)->tif_rawcp++ = (tidataval_t) (sp)->data;		\
560	(tif)->tif_rawcc++;					\
561	(sp)->data = 0, (sp)->bit = 8;				\
562}
563#define	_FlushBits(tif) {					\
564	if ((tif)->tif_rawcc >= (tif)->tif_rawdatasize)		\
565		(void) TIFFFlushData1(tif);			\
566	*(tif)->tif_rawcp++ = (tidataval_t) data;		\
567	(tif)->tif_rawcc++;					\
568	data = 0, bit = 8;					\
569}
570static const int _msbmask[9] =
571    { 0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff };
572#define	_PutBits(tif, bits, length) {				\
573	while (length > bit) {					\
574		data |= bits >> (length - bit);			\
575		length -= bit;					\
576		_FlushBits(tif);				\
577	}							\
578	data |= (bits & _msbmask[length]) << (bit - length);	\
579	bit -= length;						\
580	if (bit == 0)						\
581		_FlushBits(tif);				\
582}
583
584/*
585 * Write a variable-length bit-value to
586 * the output stream.  Values are
587 * assumed to be at most 16 bits.
588 */
589static void
590Fax3PutBits(TIFF* tif, unsigned int bits, unsigned int length)
591{
592	Fax3CodecState* sp = EncoderState(tif);
593	unsigned int bit = sp->bit;
594	int data = sp->data;
595
596	_PutBits(tif, bits, length);
597
598	sp->data = data;
599	sp->bit = bit;
600}
601
602/*
603 * Write a code to the output stream.
604 */
605#define putcode(tif, te)	Fax3PutBits(tif, (te)->code, (te)->length)
606
607#ifdef FAX3_DEBUG
608#define	DEBUG_COLOR(w) (tab == TIFFFaxWhiteCodes ? w "W" : w "B")
609#define	DEBUG_PRINT(what,len) {						\
610    int t;								\
611    printf("%08X/%-2d: %s%5d\t", data, bit, DEBUG_COLOR(what), len);	\
612    for (t = length-1; t >= 0; t--)					\
613	putchar(code & (1<<t) ? '1' : '0');				\
614    putchar('\n');							\
615}
616#endif
617
618/*
619 * Write the sequence of codes that describes
620 * the specified span of zero's or one's.  The
621 * appropriate table that holds the make-up and
622 * terminating codes is supplied.
623 */
624static void
625putspan(TIFF* tif, int32 span, const tableentry* tab)
626{
627	Fax3CodecState* sp = EncoderState(tif);
628	unsigned int bit = sp->bit;
629	int data = sp->data;
630	unsigned int code, length;
631
632	while (span >= 2624) {
633		const tableentry* te = &tab[63 + (2560>>6)];
634		code = te->code, length = te->length;
635#ifdef FAX3_DEBUG
636		DEBUG_PRINT("MakeUp", te->runlen);
637#endif
638		_PutBits(tif, code, length);
639		span -= te->runlen;
640	}
641	if (span >= 64) {
642		const tableentry* te = &tab[63 + (span>>6)];
643		assert(te->runlen == 64*(span>>6));
644		code = te->code, length = te->length;
645#ifdef FAX3_DEBUG
646		DEBUG_PRINT("MakeUp", te->runlen);
647#endif
648		_PutBits(tif, code, length);
649		span -= te->runlen;
650	}
651	code = tab[span].code, length = tab[span].length;
652#ifdef FAX3_DEBUG
653	DEBUG_PRINT("  Term", tab[span].runlen);
654#endif
655	_PutBits(tif, code, length);
656
657	sp->data = data;
658	sp->bit = bit;
659}
660
661/*
662 * Write an EOL code to the output stream.  The zero-fill
663 * logic for byte-aligning encoded scanlines is handled
664 * here.  We also handle writing the tag bit for the next
665 * scanline when doing 2d encoding.
666 */
667static void
668Fax3PutEOL(TIFF* tif)
669{
670	Fax3CodecState* sp = EncoderState(tif);
671	unsigned int bit = sp->bit;
672	int data = sp->data;
673	unsigned int code, length, tparm;
674
675	if (sp->b.groupoptions & GROUP3OPT_FILLBITS) {
676		/*
677		 * Force bit alignment so EOL will terminate on
678		 * a byte boundary.  That is, force the bit alignment
679		 * to 16-12 = 4 before putting out the EOL code.
680		 */
681		int align = 8 - 4;
682		if (align != sp->bit) {
683			if (align > sp->bit)
684				align = sp->bit + (8 - align);
685			else
686				align = sp->bit - align;
687			code = 0;
688			tparm=align;
689			_PutBits(tif, 0, tparm);
690		}
691	}
692	code = EOL, length = 12;
693	if (is2DEncoding(sp))
694		code = (code<<1) | (sp->tag == G3_1D), length++;
695	_PutBits(tif, code, length);
696
697	sp->data = data;
698	sp->bit = bit;
699}
700
701/*
702 * Reset encoding state at the start of a strip.
703 */
704static int
705Fax3PreEncode(TIFF* tif, tsample_t s)
706{
707	Fax3CodecState* sp = EncoderState(tif);
708
709	(void) s;
710	assert(sp != NULL);
711	sp->bit = 8;
712	sp->data = 0;
713	sp->tag = G3_1D;
714	/*
715	 * This is necessary for Group 4; otherwise it isn't
716	 * needed because the first scanline of each strip ends
717	 * up being copied into the refline.
718	 */
719	if (sp->refline)
720		_TIFFmemset(sp->refline, 0x00, sp->b.rowbytes);
721	if (is2DEncoding(sp)) {
722		float res = tif->tif_dir.td_yresolution;
723		/*
724		 * The CCITT spec says that when doing 2d encoding, you
725		 * should only do it on K consecutive scanlines, where K
726		 * depends on the resolution of the image being encoded
727		 * (2 for <= 200 lpi, 4 for > 200 lpi).  Since the directory
728		 * code initializes td_yresolution to 0, this code will
729		 * select a K of 2 unless the YResolution tag is set
730		 * appropriately.  (Note also that we fudge a little here
731		 * and use 150 lpi to avoid problems with units conversion.)
732		 */
733		if (tif->tif_dir.td_resolutionunit == RESUNIT_CENTIMETER)
734			res *= 2.54f;		/* convert to inches */
735		sp->maxk = (res > 150 ? 4 : 2);
736		sp->k = sp->maxk-1;
737	} else
738		sp->k = sp->maxk = 0;
739	sp->line = 0;
740	return (1);
741}
742
743static const unsigned char zeroruns[256] = {
744    8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,	/* 0x00 - 0x0f */
745    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,	/* 0x10 - 0x1f */
746    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0x20 - 0x2f */
747    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0x30 - 0x3f */
748    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x40 - 0x4f */
749    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x50 - 0x5f */
750    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x60 - 0x6f */
751    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x70 - 0x7f */
752    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x80 - 0x8f */
753    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x90 - 0x9f */
754    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xa0 - 0xaf */
755    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xb0 - 0xbf */
756    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xc0 - 0xcf */
757    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xd0 - 0xdf */
758    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xe0 - 0xef */
759    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xf0 - 0xff */
760};
761static const unsigned char oneruns[256] = {
762    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x00 - 0x0f */
763    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x10 - 0x1f */
764    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x20 - 0x2f */
765    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x30 - 0x3f */
766    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x40 - 0x4f */
767    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x50 - 0x5f */
768    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x60 - 0x6f */
769    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x70 - 0x7f */
770    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x80 - 0x8f */
771    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x90 - 0x9f */
772    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0xa0 - 0xaf */
773    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0xb0 - 0xbf */
774    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0xc0 - 0xcf */
775    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0xd0 - 0xdf */
776    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,	/* 0xe0 - 0xef */
777    4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 7, 8,	/* 0xf0 - 0xff */
778};
779
780/*
781 * On certain systems it pays to inline
782 * the routines that find pixel spans.
783 */
784#ifdef VAXC
785static	int32 find0span(unsigned char*, int32, int32);
786static	int32 find1span(unsigned char*, int32, int32);
787#pragma inline(find0span,find1span)
788#endif
789
790/*
791 * Find a span of ones or zeros using the supplied
792 * table.  The ``base'' of the bit string is supplied
793 * along with the start+end bit indices.
794 */
795static int32
796find0span(unsigned char* bp, int32 bs, int32 be)
797{
798	int32 bits = be - bs;
799	int32 n, span;
800
801	bp += bs>>3;
802	/*
803	 * Check partial byte on lhs.
804	 */
805	if (bits > 0 && (n = (bs & 7))) {
806		span = zeroruns[(*bp << n) & 0xff];
807		if (span > 8-n)		/* table value too generous */
808			span = 8-n;
809		if (span > bits)	/* constrain span to bit range */
810			span = bits;
811		if (n+span < 8)		/* doesn't extend to edge of byte */
812			return (span);
813		bits -= span;
814		bp++;
815	} else
816		span = 0;
817	if (bits >= (int32)(2 * 8 * sizeof(long))) {
818		long* lp;
819		/*
820		 * Align to longword boundary and check longwords.
821		 */
822		while (!isAligned(bp, long)) {
823			if (*bp != 0x00)
824				return (span + zeroruns[*bp]);
825			span += 8, bits -= 8;
826			bp++;
827		}
828		lp = (long*) bp;
829		while ((bits >= (int32)(8 * sizeof(long))) && (0 == *lp)) {
830			span += 8*sizeof (long), bits -= 8*sizeof (long);
831			lp++;
832		}
833		bp = (unsigned char*) lp;
834	}
835	/*
836	 * Scan full bytes for all 0's.
837	 */
838	while (bits >= 8) {
839		if (*bp != 0x00)	/* end of run */
840			return (span + zeroruns[*bp]);
841		span += 8, bits -= 8;
842		bp++;
843	}
844	/*
845	 * Check partial byte on rhs.
846	 */
847	if (bits > 0) {
848		n = zeroruns[*bp];
849		span += (n > bits ? bits : n);
850	}
851	return (span);
852}
853
854static int32
855find1span(unsigned char* bp, int32 bs, int32 be)
856{
857	int32 bits = be - bs;
858	int32 n, span;
859
860	bp += bs>>3;
861	/*
862	 * Check partial byte on lhs.
863	 */
864	if (bits > 0 && (n = (bs & 7))) {
865		span = oneruns[(*bp << n) & 0xff];
866		if (span > 8-n)		/* table value too generous */
867			span = 8-n;
868		if (span > bits)	/* constrain span to bit range */
869			span = bits;
870		if (n+span < 8)		/* doesn't extend to edge of byte */
871			return (span);
872		bits -= span;
873		bp++;
874	} else
875		span = 0;
876	if (bits >= (int32)(2 * 8 * sizeof(long))) {
877		long* lp;
878		/*
879		 * Align to longword boundary and check longwords.
880		 */
881		while (!isAligned(bp, long)) {
882			if (*bp != 0xff)
883				return (span + oneruns[*bp]);
884			span += 8, bits -= 8;
885			bp++;
886		}
887		lp = (long*) bp;
888		while ((bits >= (int32)(8 * sizeof(long))) && (~0 == *lp)) {
889			span += 8*sizeof (long), bits -= 8*sizeof (long);
890			lp++;
891		}
892		bp = (unsigned char*) lp;
893	}
894	/*
895	 * Scan full bytes for all 1's.
896	 */
897	while (bits >= 8) {
898		if (*bp != 0xff)	/* end of run */
899			return (span + oneruns[*bp]);
900		span += 8, bits -= 8;
901		bp++;
902	}
903	/*
904	 * Check partial byte on rhs.
905	 */
906	if (bits > 0) {
907		n = oneruns[*bp];
908		span += (n > bits ? bits : n);
909	}
910	return (span);
911}
912
913/*
914 * Return the offset of the next bit in the range
915 * [bs..be] that is different from the specified
916 * color.  The end, be, is returned if no such bit
917 * exists.
918 */
919#define	finddiff(_cp, _bs, _be, _color)	\
920	(_bs + (_color ? find1span(_cp,_bs,_be) : find0span(_cp,_bs,_be)))
921/*
922 * Like finddiff, but also check the starting bit
923 * against the end in case start > end.
924 */
925#define	finddiff2(_cp, _bs, _be, _color) \
926	(_bs < _be ? finddiff(_cp,_bs,_be,_color) : _be)
927
928/*
929 * 1d-encode a row of pixels.  The encoding is
930 * a sequence of all-white or all-black spans
931 * of pixels encoded with Huffman codes.
932 */
933static int
934Fax3Encode1DRow(TIFF* tif, unsigned char* bp, uint32 bits)
935{
936	Fax3CodecState* sp = EncoderState(tif);
937	int32 span;
938        uint32 bs = 0;
939
940	for (;;) {
941		span = find0span(bp, bs, bits);		/* white span */
942		putspan(tif, span, TIFFFaxWhiteCodes);
943		bs += span;
944		if (bs >= bits)
945			break;
946		span = find1span(bp, bs, bits);		/* black span */
947		putspan(tif, span, TIFFFaxBlackCodes);
948		bs += span;
949		if (bs >= bits)
950			break;
951	}
952	if (sp->b.mode & (FAXMODE_BYTEALIGN|FAXMODE_WORDALIGN)) {
953		if (sp->bit != 8)			/* byte-align */
954			Fax3FlushBits(tif, sp);
955		if ((sp->b.mode&FAXMODE_WORDALIGN) &&
956		    !isAligned(tif->tif_rawcp, uint16))
957			Fax3FlushBits(tif, sp);
958	}
959	return (1);
960}
961
962static const tableentry horizcode =
963    { 3, 0x1, 0 };	/* 001 */
964static const tableentry passcode =
965    { 4, 0x1, 0 };	/* 0001 */
966static const tableentry vcodes[7] = {
967    { 7, 0x03, 0 },	/* 0000 011 */
968    { 6, 0x03, 0 },	/* 0000 11 */
969    { 3, 0x03, 0 },	/* 011 */
970    { 1, 0x1, 0 },	/* 1 */
971    { 3, 0x2, 0 },	/* 010 */
972    { 6, 0x02, 0 },	/* 0000 10 */
973    { 7, 0x02, 0 }	/* 0000 010 */
974};
975
976/*
977 * 2d-encode a row of pixels.  Consult the CCITT
978 * documentation for the algorithm.
979 */
980static int
981Fax3Encode2DRow(TIFF* tif, unsigned char* bp, unsigned char* rp, uint32 bits)
982{
983#define	PIXEL(buf,ix)	((((buf)[(ix)>>3]) >> (7-((ix)&7))) & 1)
984        uint32 a0 = 0;
985	uint32 a1 = (PIXEL(bp, 0) != 0 ? 0 : finddiff(bp, 0, bits, 0));
986	uint32 b1 = (PIXEL(rp, 0) != 0 ? 0 : finddiff(rp, 0, bits, 0));
987	uint32 a2, b2;
988
989	for (;;) {
990		b2 = finddiff2(rp, b1, bits, PIXEL(rp,b1));
991		if (b2 >= a1) {
992			int32 d = b1 - a1;
993			if (!(-3 <= d && d <= 3)) {	/* horizontal mode */
994				a2 = finddiff2(bp, a1, bits, PIXEL(bp,a1));
995				putcode(tif, &horizcode);
996				if (a0+a1 == 0 || PIXEL(bp, a0) == 0) {
997					putspan(tif, a1-a0, TIFFFaxWhiteCodes);
998					putspan(tif, a2-a1, TIFFFaxBlackCodes);
999				} else {
1000					putspan(tif, a1-a0, TIFFFaxBlackCodes);
1001					putspan(tif, a2-a1, TIFFFaxWhiteCodes);
1002				}
1003				a0 = a2;
1004			} else {			/* vertical mode */
1005				putcode(tif, &vcodes[d+3]);
1006				a0 = a1;
1007			}
1008		} else {				/* pass mode */
1009			putcode(tif, &passcode);
1010			a0 = b2;
1011		}
1012		if (a0 >= bits)
1013			break;
1014		a1 = finddiff(bp, a0, bits, PIXEL(bp,a0));
1015		b1 = finddiff(rp, a0, bits, !PIXEL(bp,a0));
1016		b1 = finddiff(rp, b1, bits, PIXEL(bp,a0));
1017	}
1018	return (1);
1019#undef PIXEL
1020}
1021
1022/*
1023 * Encode a buffer of pixels.
1024 */
1025static int
1026Fax3Encode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
1027{
1028	Fax3CodecState* sp = EncoderState(tif);
1029
1030	(void) s;
1031	while ((long)cc > 0) {
1032		if ((sp->b.mode & FAXMODE_NOEOL) == 0)
1033			Fax3PutEOL(tif);
1034		if (is2DEncoding(sp)) {
1035			if (sp->tag == G3_1D) {
1036				if (!Fax3Encode1DRow(tif, bp, sp->b.rowpixels))
1037					return (0);
1038				sp->tag = G3_2D;
1039			} else {
1040				if (!Fax3Encode2DRow(tif, bp, sp->refline,
1041                                                     sp->b.rowpixels))
1042					return (0);
1043				sp->k--;
1044			}
1045			if (sp->k == 0) {
1046				sp->tag = G3_1D;
1047				sp->k = sp->maxk-1;
1048			} else
1049				_TIFFmemcpy(sp->refline, bp, sp->b.rowbytes);
1050		} else {
1051			if (!Fax3Encode1DRow(tif, bp, sp->b.rowpixels))
1052				return (0);
1053		}
1054		bp += sp->b.rowbytes;
1055		cc -= sp->b.rowbytes;
1056	}
1057	return (1);
1058}
1059
1060static int
1061Fax3PostEncode(TIFF* tif)
1062{
1063	Fax3CodecState* sp = EncoderState(tif);
1064
1065	if (sp->bit != 8)
1066		Fax3FlushBits(tif, sp);
1067	return (1);
1068}
1069
1070static void
1071Fax3Close(TIFF* tif)
1072{
1073	if ((Fax3State(tif)->mode & FAXMODE_NORTC) == 0) {
1074		Fax3CodecState* sp = EncoderState(tif);
1075		unsigned int code = EOL;
1076		unsigned int length = 12;
1077		int i;
1078
1079		if (is2DEncoding(sp))
1080			code = (code<<1) | (sp->tag == G3_1D), length++;
1081		for (i = 0; i < 6; i++)
1082			Fax3PutBits(tif, code, length);
1083		Fax3FlushBits(tif, sp);
1084	}
1085}
1086
1087static void
1088Fax3Cleanup(TIFF* tif)
1089{
1090	Fax3CodecState* sp = DecoderState(tif);
1091
1092	assert(sp != 0);
1093
1094	tif->tif_tagmethods.vgetfield = sp->b.vgetparent;
1095	tif->tif_tagmethods.vsetfield = sp->b.vsetparent;
1096	tif->tif_tagmethods.printdir = sp->b.printdir;
1097
1098	if (sp->runs)
1099		_TIFFfree(sp->runs);
1100	if (sp->refline)
1101		_TIFFfree(sp->refline);
1102
1103	if (Fax3State(tif)->subaddress)
1104		_TIFFfree(Fax3State(tif)->subaddress);
1105	if (Fax3State(tif)->faxdcs)
1106		_TIFFfree(Fax3State(tif)->faxdcs);
1107
1108	_TIFFfree(tif->tif_data);
1109	tif->tif_data = NULL;
1110
1111	_TIFFSetDefaultCompressionState(tif);
1112}
1113
1114#define	FIELD_BADFAXLINES	(FIELD_CODEC+0)
1115#define	FIELD_CLEANFAXDATA	(FIELD_CODEC+1)
1116#define	FIELD_BADFAXRUN		(FIELD_CODEC+2)
1117#define	FIELD_RECVPARAMS	(FIELD_CODEC+3)
1118#define	FIELD_SUBADDRESS	(FIELD_CODEC+4)
1119#define	FIELD_RECVTIME		(FIELD_CODEC+5)
1120#define	FIELD_FAXDCS		(FIELD_CODEC+6)
1121
1122#define	FIELD_OPTIONS		(FIELD_CODEC+7)
1123
1124static const TIFFFieldInfo faxFieldInfo[] = {
1125    { TIFFTAG_FAXMODE,		 0, 0,	TIFF_ANY,	FIELD_PSEUDO,
1126      FALSE,	FALSE,	"FaxMode" },
1127    { TIFFTAG_FAXFILLFUNC,	 0, 0,	TIFF_ANY,	FIELD_PSEUDO,
1128      FALSE,	FALSE,	"FaxFillFunc" },
1129    { TIFFTAG_BADFAXLINES,	 1, 1,	TIFF_LONG,	FIELD_BADFAXLINES,
1130      TRUE,	FALSE,	"BadFaxLines" },
1131    { TIFFTAG_BADFAXLINES,	 1, 1,	TIFF_SHORT,	FIELD_BADFAXLINES,
1132      TRUE,	FALSE,	"BadFaxLines" },
1133    { TIFFTAG_CLEANFAXDATA,	 1, 1,	TIFF_SHORT,	FIELD_CLEANFAXDATA,
1134      TRUE,	FALSE,	"CleanFaxData" },
1135    { TIFFTAG_CONSECUTIVEBADFAXLINES,1,1, TIFF_LONG,	FIELD_BADFAXRUN,
1136      TRUE,	FALSE,	"ConsecutiveBadFaxLines" },
1137    { TIFFTAG_CONSECUTIVEBADFAXLINES,1,1, TIFF_SHORT,	FIELD_BADFAXRUN,
1138      TRUE,	FALSE,	"ConsecutiveBadFaxLines" },
1139    { TIFFTAG_FAXRECVPARAMS,	 1, 1, TIFF_LONG,	FIELD_RECVPARAMS,
1140      TRUE,	FALSE,	"FaxRecvParams" },
1141    { TIFFTAG_FAXSUBADDRESS,	-1,-1, TIFF_ASCII,	FIELD_SUBADDRESS,
1142      TRUE,	FALSE,	"FaxSubAddress" },
1143    { TIFFTAG_FAXRECVTIME,	 1, 1, TIFF_LONG,	FIELD_RECVTIME,
1144      TRUE,	FALSE,	"FaxRecvTime" },
1145    { TIFFTAG_FAXDCS,		-1,-1, TIFF_ASCII,	FIELD_FAXDCS,
1146      TRUE,	FALSE,	"FaxDcs" },
1147};
1148static const TIFFFieldInfo fax3FieldInfo[] = {
1149    { TIFFTAG_GROUP3OPTIONS,	 1, 1,	TIFF_LONG,	FIELD_OPTIONS,
1150      FALSE,	FALSE,	"Group3Options" },
1151};
1152static const TIFFFieldInfo fax4FieldInfo[] = {
1153    { TIFFTAG_GROUP4OPTIONS,	 1, 1,	TIFF_LONG,	FIELD_OPTIONS,
1154      FALSE,	FALSE,	"Group4Options" },
1155};
1156#define	N(a)	(sizeof (a) / sizeof (a[0]))
1157
1158static int
1159Fax3VSetField(TIFF* tif, ttag_t tag, va_list ap)
1160{
1161	Fax3BaseState* sp = Fax3State(tif);
1162	const TIFFFieldInfo* fip;
1163
1164	assert(sp != 0);
1165	assert(sp->vsetparent != 0);
1166
1167	switch (tag) {
1168	case TIFFTAG_FAXMODE:
1169		sp->mode = va_arg(ap, int);
1170		return 1;			/* NB: pseudo tag */
1171	case TIFFTAG_FAXFILLFUNC:
1172		DecoderState(tif)->fill = va_arg(ap, TIFFFaxFillFunc);
1173		return 1;			/* NB: pseudo tag */
1174	case TIFFTAG_GROUP3OPTIONS:
1175		/* XXX: avoid reading options if compression mismatches. */
1176		if (tif->tif_dir.td_compression == COMPRESSION_CCITTFAX3)
1177			sp->groupoptions = va_arg(ap, uint32);
1178		break;
1179	case TIFFTAG_GROUP4OPTIONS:
1180		/* XXX: avoid reading options if compression mismatches. */
1181		if (tif->tif_dir.td_compression == COMPRESSION_CCITTFAX4)
1182			sp->groupoptions = va_arg(ap, uint32);
1183		break;
1184	case TIFFTAG_BADFAXLINES:
1185		sp->badfaxlines = va_arg(ap, uint32);
1186		break;
1187	case TIFFTAG_CLEANFAXDATA:
1188		sp->cleanfaxdata = (uint16) va_arg(ap, int);
1189		break;
1190	case TIFFTAG_CONSECUTIVEBADFAXLINES:
1191		sp->badfaxrun = va_arg(ap, uint32);
1192		break;
1193	case TIFFTAG_FAXRECVPARAMS:
1194		sp->recvparams = va_arg(ap, uint32);
1195		break;
1196	case TIFFTAG_FAXSUBADDRESS:
1197		_TIFFsetString(&sp->subaddress, va_arg(ap, char*));
1198		break;
1199	case TIFFTAG_FAXRECVTIME:
1200		sp->recvtime = va_arg(ap, uint32);
1201		break;
1202	case TIFFTAG_FAXDCS:
1203		_TIFFsetString(&sp->faxdcs, va_arg(ap, char*));
1204		break;
1205	default:
1206		return (*sp->vsetparent)(tif, tag, ap);
1207	}
1208
1209	if ((fip = _TIFFFieldWithTag(tif, tag)))
1210		TIFFSetFieldBit(tif, fip->field_bit);
1211	else
1212		return 0;
1213
1214	tif->tif_flags |= TIFF_DIRTYDIRECT;
1215	return 1;
1216}
1217
1218static int
1219Fax3VGetField(TIFF* tif, ttag_t tag, va_list ap)
1220{
1221	Fax3BaseState* sp = Fax3State(tif);
1222
1223	assert(sp != 0);
1224
1225	switch (tag) {
1226	case TIFFTAG_FAXMODE:
1227		*va_arg(ap, int*) = sp->mode;
1228		break;
1229	case TIFFTAG_FAXFILLFUNC:
1230		*va_arg(ap, TIFFFaxFillFunc*) = DecoderState(tif)->fill;
1231		break;
1232	case TIFFTAG_GROUP3OPTIONS:
1233	case TIFFTAG_GROUP4OPTIONS:
1234		*va_arg(ap, uint32*) = sp->groupoptions;
1235		break;
1236	case TIFFTAG_BADFAXLINES:
1237		*va_arg(ap, uint32*) = sp->badfaxlines;
1238		break;
1239	case TIFFTAG_CLEANFAXDATA:
1240		*va_arg(ap, uint16*) = sp->cleanfaxdata;
1241		break;
1242	case TIFFTAG_CONSECUTIVEBADFAXLINES:
1243		*va_arg(ap, uint32*) = sp->badfaxrun;
1244		break;
1245	case TIFFTAG_FAXRECVPARAMS:
1246		*va_arg(ap, uint32*) = sp->recvparams;
1247		break;
1248	case TIFFTAG_FAXSUBADDRESS:
1249		*va_arg(ap, char**) = sp->subaddress;
1250		break;
1251	case TIFFTAG_FAXRECVTIME:
1252		*va_arg(ap, uint32*) = sp->recvtime;
1253		break;
1254	case TIFFTAG_FAXDCS:
1255		*va_arg(ap, char**) = sp->faxdcs;
1256		break;
1257	default:
1258		return (*sp->vgetparent)(tif, tag, ap);
1259	}
1260	return (1);
1261}
1262
1263static void
1264Fax3PrintDir(TIFF* tif, FILE* fd, long flags)
1265{
1266	Fax3BaseState* sp = Fax3State(tif);
1267
1268	assert(sp != 0);
1269
1270	(void) flags;
1271	if (TIFFFieldSet(tif,FIELD_OPTIONS)) {
1272		const char* sep = " ";
1273		if (tif->tif_dir.td_compression == COMPRESSION_CCITTFAX4) {
1274			fprintf(fd, "  Group 4 Options:");
1275			if (sp->groupoptions & GROUP4OPT_UNCOMPRESSED)
1276				fprintf(fd, "%suncompressed data", sep);
1277		} else {
1278
1279			fprintf(fd, "  Group 3 Options:");
1280			if (sp->groupoptions & GROUP3OPT_2DENCODING)
1281				fprintf(fd, "%s2-d encoding", sep), sep = "+";
1282			if (sp->groupoptions & GROUP3OPT_FILLBITS)
1283				fprintf(fd, "%sEOL padding", sep), sep = "+";
1284			if (sp->groupoptions & GROUP3OPT_UNCOMPRESSED)
1285				fprintf(fd, "%suncompressed data", sep);
1286		}
1287		fprintf(fd, " (%lu = 0x%lx)\n",
1288                        (unsigned long) sp->groupoptions,
1289                        (unsigned long) sp->groupoptions);
1290	}
1291	if (TIFFFieldSet(tif,FIELD_CLEANFAXDATA)) {
1292		fprintf(fd, "  Fax Data:");
1293		switch (sp->cleanfaxdata) {
1294		case CLEANFAXDATA_CLEAN:
1295			fprintf(fd, " clean");
1296			break;
1297		case CLEANFAXDATA_REGENERATED:
1298			fprintf(fd, " receiver regenerated");
1299			break;
1300		case CLEANFAXDATA_UNCLEAN:
1301			fprintf(fd, " uncorrected errors");
1302			break;
1303		}
1304		fprintf(fd, " (%u = 0x%x)\n",
1305		    sp->cleanfaxdata, sp->cleanfaxdata);
1306	}
1307	if (TIFFFieldSet(tif,FIELD_BADFAXLINES))
1308		fprintf(fd, "  Bad Fax Lines: %lu\n",
1309                        (unsigned long) sp->badfaxlines);
1310	if (TIFFFieldSet(tif,FIELD_BADFAXRUN))
1311		fprintf(fd, "  Consecutive Bad Fax Lines: %lu\n",
1312		    (unsigned long) sp->badfaxrun);
1313	if (TIFFFieldSet(tif,FIELD_RECVPARAMS))
1314		fprintf(fd, "  Fax Receive Parameters: %08lx\n",
1315		   (unsigned long) sp->recvparams);
1316	if (TIFFFieldSet(tif,FIELD_SUBADDRESS))
1317		fprintf(fd, "  Fax SubAddress: %s\n", sp->subaddress);
1318	if (TIFFFieldSet(tif,FIELD_RECVTIME))
1319		fprintf(fd, "  Fax Receive Time: %lu secs\n",
1320		    (unsigned long) sp->recvtime);
1321	if (TIFFFieldSet(tif,FIELD_FAXDCS))
1322		fprintf(fd, "  Fax DCS: %s\n", sp->faxdcs);
1323}
1324
1325static int
1326InitCCITTFax3(TIFF* tif)
1327{
1328	Fax3BaseState* sp;
1329
1330	/*
1331	 * Merge codec-specific tag information.
1332	 */
1333	if (!_TIFFMergeFieldInfo(tif, faxFieldInfo, N(faxFieldInfo))) {
1334		TIFFErrorExt(tif->tif_clientdata, "InitCCITTFax3",
1335			"Merging common CCITT Fax codec-specific tags failed");
1336		return 0;
1337	}
1338
1339	/*
1340	 * Allocate state block so tag methods have storage to record values.
1341	 */
1342	tif->tif_data = (tidata_t)
1343		_TIFFmalloc(sizeof (Fax3CodecState));
1344
1345	if (tif->tif_data == NULL) {
1346		TIFFErrorExt(tif->tif_clientdata, "TIFFInitCCITTFax3",
1347		    "%s: No space for state block", tif->tif_name);
1348		return (0);
1349	}
1350
1351	sp = Fax3State(tif);
1352        sp->rw_mode = tif->tif_mode;
1353
1354	/*
1355	 * Override parent get/set field methods.
1356	 */
1357	sp->vgetparent = tif->tif_tagmethods.vgetfield;
1358	tif->tif_tagmethods.vgetfield = Fax3VGetField; /* hook for codec tags */
1359	sp->vsetparent = tif->tif_tagmethods.vsetfield;
1360	tif->tif_tagmethods.vsetfield = Fax3VSetField; /* hook for codec tags */
1361	sp->printdir = tif->tif_tagmethods.printdir;
1362	tif->tif_tagmethods.printdir = Fax3PrintDir;   /* hook for codec tags */
1363	sp->groupoptions = 0;
1364	sp->recvparams = 0;
1365	sp->subaddress = NULL;
1366	sp->faxdcs = NULL;
1367
1368	if (sp->rw_mode == O_RDONLY) /* FIXME: improve for in place update */
1369		tif->tif_flags |= TIFF_NOBITREV; /* decoder does bit reversal */
1370	DecoderState(tif)->runs = NULL;
1371	TIFFSetField(tif, TIFFTAG_FAXFILLFUNC, _TIFFFax3fillruns);
1372	EncoderState(tif)->refline = NULL;
1373
1374	/*
1375	 * Install codec methods.
1376	 */
1377	tif->tif_setupdecode = Fax3SetupState;
1378	tif->tif_predecode = Fax3PreDecode;
1379	tif->tif_decoderow = Fax3Decode1D;
1380	tif->tif_decodestrip = Fax3Decode1D;
1381	tif->tif_decodetile = Fax3Decode1D;
1382	tif->tif_setupencode = Fax3SetupState;
1383	tif->tif_preencode = Fax3PreEncode;
1384	tif->tif_postencode = Fax3PostEncode;
1385	tif->tif_encoderow = Fax3Encode;
1386	tif->tif_encodestrip = Fax3Encode;
1387	tif->tif_encodetile = Fax3Encode;
1388	tif->tif_close = Fax3Close;
1389	tif->tif_cleanup = Fax3Cleanup;
1390
1391	return (1);
1392}
1393
1394int
1395TIFFInitCCITTFax3(TIFF* tif, int scheme)
1396{
1397	(void) scheme;
1398	if (InitCCITTFax3(tif)) {
1399		/*
1400		 * Merge codec-specific tag information.
1401		 */
1402		if (!_TIFFMergeFieldInfo(tif, fax3FieldInfo, N(fax3FieldInfo))) {
1403			TIFFErrorExt(tif->tif_clientdata, "TIFFInitCCITTFax3",
1404			"Merging CCITT Fax 3 codec-specific tags failed");
1405			return 0;
1406		}
1407
1408		/*
1409		 * The default format is Class/F-style w/o RTC.
1410		 */
1411		return TIFFSetField(tif, TIFFTAG_FAXMODE, FAXMODE_CLASSF);
1412	} else
1413		return 01;
1414}
1415
1416/*
1417 * CCITT Group 4 (T.6) Facsimile-compatible
1418 * Compression Scheme Support.
1419 */
1420
1421#define	SWAP(t,a,b)	{ t x; x = (a); (a) = (b); (b) = x; }
1422/*
1423 * Decode the requested amount of G4-encoded data.
1424 */
1425static int
1426Fax4Decode(TIFF* tif, tidata_t buf, tsize_t occ, tsample_t s)
1427{
1428	DECLARE_STATE_2D(tif, sp, "Fax4Decode");
1429
1430	(void) s;
1431	CACHE_STATE(tif, sp);
1432	while ((long)occ > 0) {
1433		a0 = 0;
1434		RunLength = 0;
1435		pa = thisrun = sp->curruns;
1436		pb = sp->refruns;
1437		b1 = *pb++;
1438#ifdef FAX3_DEBUG
1439		printf("\nBitAcc=%08X, BitsAvail = %d\n", BitAcc, BitsAvail);
1440		printf("-------------------- %d\n", tif->tif_row);
1441		fflush(stdout);
1442#endif
1443		EXPAND2D(EOFG4);
1444                if (EOLcnt)
1445                    goto EOFG4;
1446		(*sp->fill)(buf, thisrun, pa, lastx);
1447		SETVALUE(0);		/* imaginary change for reference */
1448		SWAP(uint32*, sp->curruns, sp->refruns);
1449		buf += sp->b.rowbytes;
1450		occ -= sp->b.rowbytes;
1451		sp->line++;
1452		continue;
1453	EOFG4:
1454                NeedBits16( 13, BADG4 );
1455        BADG4:
1456#ifdef FAX3_DEBUG
1457                if( GetBits(13) != 0x1001 )
1458                    fputs( "Bad EOFB\n", stderr );
1459#endif
1460                ClrBits( 13 );
1461		(*sp->fill)(buf, thisrun, pa, lastx);
1462		UNCACHE_STATE(tif, sp);
1463		return ( sp->line ? 1 : -1);	/* don't error on badly-terminated strips */
1464	}
1465	UNCACHE_STATE(tif, sp);
1466	return (1);
1467}
1468#undef	SWAP
1469
1470/*
1471 * Encode the requested amount of data.
1472 */
1473static int
1474Fax4Encode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
1475{
1476	Fax3CodecState *sp = EncoderState(tif);
1477
1478	(void) s;
1479	while ((long)cc > 0) {
1480		if (!Fax3Encode2DRow(tif, bp, sp->refline, sp->b.rowpixels))
1481			return (0);
1482		_TIFFmemcpy(sp->refline, bp, sp->b.rowbytes);
1483		bp += sp->b.rowbytes;
1484		cc -= sp->b.rowbytes;
1485	}
1486	return (1);
1487}
1488
1489static int
1490Fax4PostEncode(TIFF* tif)
1491{
1492	Fax3CodecState *sp = EncoderState(tif);
1493
1494	/* terminate strip w/ EOFB */
1495	Fax3PutBits(tif, EOL, 12);
1496	Fax3PutBits(tif, EOL, 12);
1497	if (sp->bit != 8)
1498		Fax3FlushBits(tif, sp);
1499	return (1);
1500}
1501
1502int
1503TIFFInitCCITTFax4(TIFF* tif, int scheme)
1504{
1505	(void) scheme;
1506	if (InitCCITTFax3(tif)) {		/* reuse G3 support */
1507		/*
1508		 * Merge codec-specific tag information.
1509		 */
1510		if (!_TIFFMergeFieldInfo(tif, fax4FieldInfo, N(fax4FieldInfo))) {
1511			TIFFErrorExt(tif->tif_clientdata, "TIFFInitCCITTFax4",
1512			"Merging CCITT Fax 4 codec-specific tags failed");
1513			return 0;
1514		}
1515
1516		tif->tif_decoderow = Fax4Decode;
1517		tif->tif_decodestrip = Fax4Decode;
1518		tif->tif_decodetile = Fax4Decode;
1519		tif->tif_encoderow = Fax4Encode;
1520		tif->tif_encodestrip = Fax4Encode;
1521		tif->tif_encodetile = Fax4Encode;
1522		tif->tif_postencode = Fax4PostEncode;
1523		/*
1524		 * Suppress RTC at the end of each strip.
1525		 */
1526		return TIFFSetField(tif, TIFFTAG_FAXMODE, FAXMODE_NORTC);
1527	} else
1528		return (0);
1529}
1530
1531/*
1532 * CCITT Group 3 1-D Modified Huffman RLE Compression Support.
1533 * (Compression algorithms 2 and 32771)
1534 */
1535
1536/*
1537 * Decode the requested amount of RLE-encoded data.
1538 */
1539static int
1540Fax3DecodeRLE(TIFF* tif, tidata_t buf, tsize_t occ, tsample_t s)
1541{
1542	DECLARE_STATE(tif, sp, "Fax3DecodeRLE");
1543	int mode = sp->b.mode;
1544
1545	(void) s;
1546	CACHE_STATE(tif, sp);
1547	thisrun = sp->curruns;
1548	while ((long)occ > 0) {
1549		a0 = 0;
1550		RunLength = 0;
1551		pa = thisrun;
1552#ifdef FAX3_DEBUG
1553		printf("\nBitAcc=%08X, BitsAvail = %d\n", BitAcc, BitsAvail);
1554		printf("-------------------- %d\n", tif->tif_row);
1555		fflush(stdout);
1556#endif
1557		EXPAND1D(EOFRLE);
1558		(*sp->fill)(buf, thisrun, pa, lastx);
1559		/*
1560		 * Cleanup at the end of the row.
1561		 */
1562		if (mode & FAXMODE_BYTEALIGN) {
1563			int n = BitsAvail - (BitsAvail &~ 7);
1564			ClrBits(n);
1565		} else if (mode & FAXMODE_WORDALIGN) {
1566			int n = BitsAvail - (BitsAvail &~ 15);
1567			ClrBits(n);
1568			if (BitsAvail == 0 && !isAligned(cp, uint16))
1569			    cp++;
1570		}
1571		buf += sp->b.rowbytes;
1572		occ -= sp->b.rowbytes;
1573		sp->line++;
1574		continue;
1575	EOFRLE:				/* premature EOF */
1576		(*sp->fill)(buf, thisrun, pa, lastx);
1577		UNCACHE_STATE(tif, sp);
1578		return (-1);
1579	}
1580	UNCACHE_STATE(tif, sp);
1581	return (1);
1582}
1583
1584int
1585TIFFInitCCITTRLE(TIFF* tif, int scheme)
1586{
1587	(void) scheme;
1588	if (InitCCITTFax3(tif)) {		/* reuse G3 support */
1589		tif->tif_decoderow = Fax3DecodeRLE;
1590		tif->tif_decodestrip = Fax3DecodeRLE;
1591		tif->tif_decodetile = Fax3DecodeRLE;
1592		/*
1593		 * Suppress RTC+EOLs when encoding and byte-align data.
1594		 */
1595		return TIFFSetField(tif, TIFFTAG_FAXMODE,
1596		    FAXMODE_NORTC|FAXMODE_NOEOL|FAXMODE_BYTEALIGN);
1597	} else
1598		return (0);
1599}
1600
1601int
1602TIFFInitCCITTRLEW(TIFF* tif, int scheme)
1603{
1604	(void) scheme;
1605	if (InitCCITTFax3(tif)) {		/* reuse G3 support */
1606		tif->tif_decoderow = Fax3DecodeRLE;
1607		tif->tif_decodestrip = Fax3DecodeRLE;
1608		tif->tif_decodetile = Fax3DecodeRLE;
1609		/*
1610		 * Suppress RTC+EOLs when encoding and word-align data.
1611		 */
1612		return TIFFSetField(tif, TIFFTAG_FAXMODE,
1613		    FAXMODE_NORTC|FAXMODE_NOEOL|FAXMODE_WORDALIGN);
1614	} else
1615		return (0);
1616}
1617#endif /* CCITT_SUPPORT */
1618
1619/* vim: set ts=8 sts=8 sw=8 noet: */
1620/*
1621 * Local Variables:
1622 * mode: c
1623 * c-basic-offset: 8
1624 * fill-column: 78
1625 * End:
1626 */
1627