1/*
2 * Copyright (c) 1997 Greg Ward Larson
3 * Copyright (c) 1997 Silicon Graphics, Inc.
4 *
5 * Permission to use, copy, modify, distribute, and sell this software and
6 * its documentation for any purpose is hereby granted without fee, provided
7 * that (i) the above copyright notices and this permission notice appear in
8 * all copies of the software and related documentation, and (ii) the names of
9 * Sam Leffler, Greg Larson and Silicon Graphics may not be used in any
10 * advertising or publicity relating to the software without the specific,
11 * prior written permission of Sam Leffler, Greg Larson and Silicon Graphics.
12 *
13 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
14 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
15 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
16 *
17 * IN NO EVENT SHALL SAM LEFFLER, GREG LARSON OR SILICON GRAPHICS BE LIABLE
18 * FOR ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
19 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
20 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
21 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
22 * OF THIS SOFTWARE.
23 */
24
25#include "tiffiop.h"
26#ifdef LOGLUV_SUPPORT
27
28/*
29 * TIFF Library.
30 * LogLuv compression support for high dynamic range images.
31 *
32 * Contributed by Greg Larson.
33 *
34 * LogLuv image support uses the TIFF library to store 16 or 10-bit
35 * log luminance values with 8 bits each of u and v or a 14-bit index.
36 *
37 * The codec can take as input and produce as output 32-bit IEEE float values
38 * as well as 16-bit integer values.  A 16-bit luminance is interpreted
39 * as a sign bit followed by a 15-bit integer that is converted
40 * to and from a linear magnitude using the transformation:
41 *
42 *	L = 2^( (Le+.5)/256 - 64 )		# real from 15-bit
43 *
44 *	Le = floor( 256*(log2(L) + 64) )	# 15-bit from real
45 *
46 * The actual conversion to world luminance units in candelas per sq. meter
47 * requires an additional multiplier, which is stored in the TIFFTAG_STONITS.
48 * This value is usually set such that a reasonable exposure comes from
49 * clamping decoded luminances above 1 to 1 in the displayed image.
50 *
51 * The 16-bit values for u and v may be converted to real values by dividing
52 * each by 32768.  (This allows for negative values, which aren't useful as
53 * far as we know, but are left in case of future improvements in human
54 * color vision.)
55 *
56 * Conversion from (u,v), which is actually the CIE (u',v') system for
57 * you color scientists, is accomplished by the following transformation:
58 *
59 *	u = 4*x / (-2*x + 12*y + 3)
60 *	v = 9*y / (-2*x + 12*y + 3)
61 *
62 *	x = 9*u / (6*u - 16*v + 12)
63 *	y = 4*v / (6*u - 16*v + 12)
64 *
65 * This process is greatly simplified by passing 32-bit IEEE floats
66 * for each of three CIE XYZ coordinates.  The codec then takes care
67 * of conversion to and from LogLuv, though the application is still
68 * responsible for interpreting the TIFFTAG_STONITS calibration factor.
69 *
70 * By definition, a CIE XYZ vector of [1 1 1] corresponds to a neutral white
71 * point of (x,y)=(1/3,1/3).  However, most color systems assume some other
72 * white point, such as D65, and an absolute color conversion to XYZ then
73 * to another color space with a different white point may introduce an
74 * unwanted color cast to the image.  It is often desirable, therefore, to
75 * perform a white point conversion that maps the input white to [1 1 1]
76 * in XYZ, then record the original white point using the TIFFTAG_WHITEPOINT
77 * tag value.  A decoder that demands absolute color calibration may use
78 * this white point tag to get back the original colors, but usually it
79 * will be ignored and the new white point will be used instead that
80 * matches the output color space.
81 *
82 * Pixel information is compressed into one of two basic encodings, depending
83 * on the setting of the compression tag, which is one of COMPRESSION_SGILOG
84 * or COMPRESSION_SGILOG24.  For COMPRESSION_SGILOG, greyscale data is
85 * stored as:
86 *
87 *	 1       15
88 *	|-+---------------|
89 *
90 * COMPRESSION_SGILOG color data is stored as:
91 *
92 *	 1       15           8        8
93 *	|-+---------------|--------+--------|
94 *	 S       Le           ue       ve
95 *
96 * For the 24-bit COMPRESSION_SGILOG24 color format, the data is stored as:
97 *
98 *	     10           14
99 *	|----------|--------------|
100 *	     Le'          Ce
101 *
102 * There is no sign bit in the 24-bit case, and the (u,v) chromaticity is
103 * encoded as an index for optimal color resolution.  The 10 log bits are
104 * defined by the following conversions:
105 *
106 *	L = 2^((Le'+.5)/64 - 12)		# real from 10-bit
107 *
108 *	Le' = floor( 64*(log2(L) + 12) )	# 10-bit from real
109 *
110 * The 10 bits of the smaller format may be converted into the 15 bits of
111 * the larger format by multiplying by 4 and adding 13314.  Obviously,
112 * a smaller range of magnitudes is covered (about 5 orders of magnitude
113 * instead of 38), and the lack of a sign bit means that negative luminances
114 * are not allowed.  (Well, they aren't allowed in the real world, either,
115 * but they are useful for certain types of image processing.)
116 *
117 * The desired user format is controlled by the setting the internal
118 * pseudo tag TIFFTAG_SGILOGDATAFMT to one of:
119 *  SGILOGDATAFMT_FLOAT       = IEEE 32-bit float XYZ values
120 *  SGILOGDATAFMT_16BIT	      = 16-bit integer encodings of logL, u and v
121 * Raw data i/o is also possible using:
122 *  SGILOGDATAFMT_RAW         = 32-bit unsigned integer with encoded pixel
123 * In addition, the following decoding is provided for ease of display:
124 *  SGILOGDATAFMT_8BIT        = 8-bit default RGB gamma-corrected values
125 *
126 * For grayscale images, we provide the following data formats:
127 *  SGILOGDATAFMT_FLOAT       = IEEE 32-bit float Y values
128 *  SGILOGDATAFMT_16BIT       = 16-bit integer w/ encoded luminance
129 *  SGILOGDATAFMT_8BIT        = 8-bit gray monitor values
130 *
131 * Note that the COMPRESSION_SGILOG applies a simple run-length encoding
132 * scheme by separating the logL, u and v bytes for each row and applying
133 * a PackBits type of compression.  Since the 24-bit encoding is not
134 * adaptive, the 32-bit color format takes less space in many cases.
135 *
136 * Further control is provided over the conversion from higher-resolution
137 * formats to final encoded values through the pseudo tag
138 * TIFFTAG_SGILOGENCODE:
139 *  SGILOGENCODE_NODITHER     = do not dither encoded values
140 *  SGILOGENCODE_RANDITHER    = apply random dithering during encoding
141 *
142 * The default value of this tag is SGILOGENCODE_NODITHER for
143 * COMPRESSION_SGILOG to maximize run-length encoding and
144 * SGILOGENCODE_RANDITHER for COMPRESSION_SGILOG24 to turn
145 * quantization errors into noise.
146 */
147
148#include <stdio.h>
149#include <assert.h>
150#include <stdlib.h>
151#include <math.h>
152
153/*
154 * State block for each open TIFF
155 * file using LogLuv compression/decompression.
156 */
157typedef	struct logLuvState LogLuvState;
158
159struct logLuvState {
160	int			user_datafmt;	/* user data format */
161	int			encode_meth;	/* encoding method */
162	int			pixel_size;	/* bytes per pixel */
163
164	tidata_t*		tbuf;		/* translation buffer */
165	int			tbuflen;	/* buffer length */
166	void (*tfunc)(LogLuvState*, tidata_t, int);
167
168	TIFFVSetMethod		vgetparent;	/* super-class method */
169	TIFFVSetMethod		vsetparent;	/* super-class method */
170};
171
172#define	DecoderState(tif)	((LogLuvState*) (tif)->tif_data)
173#define	EncoderState(tif)	((LogLuvState*) (tif)->tif_data)
174
175#define N(a)   (sizeof(a)/sizeof(a[0]))
176#define SGILOGDATAFMT_UNKNOWN	-1
177
178#define MINRUN		4	/* minimum run length */
179
180/*
181 * Decode a string of 16-bit gray pixels.
182 */
183static int
184LogL16Decode(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
185{
186	LogLuvState* sp = DecoderState(tif);
187	int shft, i, npixels;
188	u_char* bp;
189	int16* tp;
190	int16 b;
191	int cc, rc;
192
193	assert(s == 0);
194	assert(sp != NULL);
195
196	npixels = occ / sp->pixel_size;
197
198	if (sp->user_datafmt == SGILOGDATAFMT_16BIT)
199		tp = (int16*) op;
200	else {
201		assert(sp->tbuflen >= npixels);
202		tp = (int16*) sp->tbuf;
203	}
204	_TIFFmemset((tdata_t) tp, 0, npixels*sizeof (tp[0]));
205
206	bp = (u_char*) tif->tif_rawcp;
207	cc = tif->tif_rawcc;
208					/* get each byte string */
209	for (shft = 2*8; (shft -= 8) >= 0; ) {
210		for (i = 0; i < npixels && cc > 0; )
211			if (*bp >= 128) {		/* run */
212				rc = *bp++ + (2-128);
213				b = (int16)(*bp++ << shft);
214				cc -= 2;
215				while (rc-- && i < npixels)
216					tp[i++] |= b;
217			} else {			/* non-run */
218				rc = *bp++;		/* nul is noop */
219				while (--cc && rc-- && i < npixels)
220					tp[i++] |= (int16)*bp++ << shft;
221			}
222		if (i != npixels) {
223			TIFFError(tif->tif_name,
224		"LogL16Decode: Not enough data at row %d (short %d pixels)",
225			    tif->tif_row, npixels - i);
226			tif->tif_rawcp = (tidata_t) bp;
227			tif->tif_rawcc = cc;
228			return (0);
229		}
230	}
231	(*sp->tfunc)(sp, op, npixels);
232	tif->tif_rawcp = (tidata_t) bp;
233	tif->tif_rawcc = cc;
234	return (1);
235}
236
237/*
238 * Decode a string of 24-bit pixels.
239 */
240static int
241LogLuvDecode24(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
242{
243	LogLuvState* sp = DecoderState(tif);
244	int cc, i, npixels;
245	u_char* bp;
246	uint32* tp;
247
248	assert(s == 0);
249	assert(sp != NULL);
250
251	npixels = occ / sp->pixel_size;
252
253	if (sp->user_datafmt == SGILOGDATAFMT_RAW)
254		tp = (uint32 *)op;
255	else {
256		assert(sp->tbuflen >= npixels);
257		tp = (uint32 *) sp->tbuf;
258	}
259					/* copy to array of uint32 */
260	bp = (u_char*) tif->tif_rawcp;
261	cc = tif->tif_rawcc;
262	for (i = 0; i < npixels && cc > 0; i++) {
263		tp[i] = bp[0] << 16 | bp[1] << 8 | bp[2];
264		bp += 3;
265		cc -= 3;
266	}
267	tif->tif_rawcp = (tidata_t) bp;
268	tif->tif_rawcc = cc;
269	if (i != npixels) {
270		TIFFError(tif->tif_name,
271	    "LogLuvDecode24: Not enough data at row %d (short %d pixels)",
272		    tif->tif_row, npixels - i);
273		return (0);
274	}
275	(*sp->tfunc)(sp, op, npixels);
276	return (1);
277}
278
279/*
280 * Decode a string of 32-bit pixels.
281 */
282static int
283LogLuvDecode32(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
284{
285	LogLuvState* sp;
286	int shft, i, npixels;
287	u_char* bp;
288	uint32* tp;
289	uint32 b;
290	int cc, rc;
291
292	assert(s == 0);
293	sp = DecoderState(tif);
294	assert(sp != NULL);
295
296	npixels = occ / sp->pixel_size;
297
298	if (sp->user_datafmt == SGILOGDATAFMT_RAW)
299		tp = (uint32*) op;
300	else {
301		assert(sp->tbuflen >= npixels);
302		tp = (uint32*) sp->tbuf;
303	}
304	_TIFFmemset((tdata_t) tp, 0, npixels*sizeof (tp[0]));
305
306	bp = (u_char*) tif->tif_rawcp;
307	cc = tif->tif_rawcc;
308					/* get each byte string */
309	for (shft = 4*8; (shft -= 8) >= 0; ) {
310		for (i = 0; i < npixels && cc > 0; )
311			if (*bp >= 128) {		/* run */
312				rc = *bp++ + (2-128);
313				b = (uint32)*bp++ << shft;
314				cc -= 2;
315				while (rc-- && i < npixels)
316					tp[i++] |= b;
317			} else {			/* non-run */
318				rc = *bp++;		/* nul is noop */
319				while (--cc && rc-- && i < npixels)
320					tp[i++] |= (uint32)*bp++ << shft;
321			}
322		if (i != npixels) {
323			TIFFError(tif->tif_name,
324		"LogLuvDecode32: Not enough data at row %d (short %d pixels)",
325			    tif->tif_row, npixels - i);
326			tif->tif_rawcp = (tidata_t) bp;
327			tif->tif_rawcc = cc;
328			return (0);
329		}
330	}
331	(*sp->tfunc)(sp, op, npixels);
332	tif->tif_rawcp = (tidata_t) bp;
333	tif->tif_rawcc = cc;
334	return (1);
335}
336
337/*
338 * Decode a strip of pixels.  We break it into rows to
339 * maintain synchrony with the encode algorithm, which
340 * is row by row.
341 */
342static int
343LogLuvDecodeStrip(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
344{
345	tsize_t rowlen = TIFFScanlineSize(tif);
346
347	assert(cc%rowlen == 0);
348	while (cc && (*tif->tif_decoderow)(tif, bp, rowlen, s))
349		bp += rowlen, cc -= rowlen;
350	return (cc == 0);
351}
352
353/*
354 * Decode a tile of pixels.  We break it into rows to
355 * maintain synchrony with the encode algorithm, which
356 * is row by row.
357 */
358static int
359LogLuvDecodeTile(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
360{
361	tsize_t rowlen = TIFFTileRowSize(tif);
362
363	assert(cc%rowlen == 0);
364	while (cc && (*tif->tif_decoderow)(tif, bp, rowlen, s))
365		bp += rowlen, cc -= rowlen;
366	return (cc == 0);
367}
368
369/*
370 * Encode a row of 16-bit pixels.
371 */
372static int
373LogL16Encode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
374{
375	LogLuvState* sp = EncoderState(tif);
376	int shft, i, j, npixels;
377	tidata_t op;
378	int16* tp;
379	int16 b;
380	int occ, rc=0, mask, beg;
381
382	assert(s == 0);
383	assert(sp != NULL);
384	npixels = cc / sp->pixel_size;
385
386	if (sp->user_datafmt == SGILOGDATAFMT_16BIT)
387		tp = (int16*) bp;
388	else {
389		tp = (int16*) sp->tbuf;
390		assert(sp->tbuflen >= npixels);
391		(*sp->tfunc)(sp, bp, npixels);
392	}
393					/* compress each byte string */
394	op = tif->tif_rawcp;
395	occ = tif->tif_rawdatasize - tif->tif_rawcc;
396	for (shft = 2*8; (shft -= 8) >= 0; )
397		for (i = 0; i < npixels; i += rc) {
398			if (occ < 4) {
399				tif->tif_rawcp = op;
400				tif->tif_rawcc = tif->tif_rawdatasize - occ;
401				if (!TIFFFlushData1(tif))
402					return (-1);
403				op = tif->tif_rawcp;
404				occ = tif->tif_rawdatasize - tif->tif_rawcc;
405			}
406			mask = 0xff << shft;		/* find next run */
407			for (beg = i; beg < npixels; beg += rc) {
408				b = (int16) (tp[beg] & mask);
409				rc = 1;
410				while (rc < 127+2 && beg+rc < npixels &&
411						(tp[beg+rc] & mask) == b)
412					rc++;
413				if (rc >= MINRUN)
414					break;		/* long enough */
415			}
416			if (beg-i > 1 && beg-i < MINRUN) {
417				b = (int16) (tp[i] & mask);/*check short run */
418				j = i+1;
419				while ((tp[j++] & mask) == b)
420                                    if (j == beg) {
421                                        *op++ = (tidataval_t)(128-2+j-i);
422                                        *op++ = (tidataval_t) (b >> shft);
423                                        occ -= 2;
424                                        i = beg;
425                                        break;
426                                    }
427			}
428			while (i < beg) {		/* write out non-run */
429				if ((j = beg-i) > 127) j = 127;
430				if (occ < j+3) {
431                                    tif->tif_rawcp = op;
432                                    tif->tif_rawcc = tif->tif_rawdatasize - occ;
433                                    if (!TIFFFlushData1(tif))
434                                        return (-1);
435                                    op = tif->tif_rawcp;
436                                    occ = tif->tif_rawdatasize - tif->tif_rawcc;
437				}
438				*op++ = (tidataval_t) j; occ--;
439				while (j--) {
440					*op++ = (tidataval_t) (tp[i++] >> shft & 0xff);
441					occ--;
442				}
443			}
444			if (rc >= MINRUN) {		/* write out run */
445				*op++ = (tidataval_t) (128-2+rc);
446				*op++ = (tidataval_t) (tp[beg] >> shft & 0xff);
447				occ -= 2;
448			} else
449				rc = 0;
450		}
451	tif->tif_rawcp = op;
452	tif->tif_rawcc = tif->tif_rawdatasize - occ;
453
454	return (0);
455}
456
457/*
458 * Encode a row of 24-bit pixels.
459 */
460static int
461LogLuvEncode24(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
462{
463	LogLuvState* sp = EncoderState(tif);
464	int i, npixels, occ;
465	tidata_t op;
466	uint32* tp;
467
468	assert(s == 0);
469	assert(sp != NULL);
470	npixels = cc / sp->pixel_size;
471
472	if (sp->user_datafmt == SGILOGDATAFMT_RAW)
473		tp = (uint32*) bp;
474	else {
475		tp = (uint32*) sp->tbuf;
476		assert(sp->tbuflen >= npixels);
477		(*sp->tfunc)(sp, bp, npixels);
478	}
479					/* write out encoded pixels */
480	op = tif->tif_rawcp;
481	occ = tif->tif_rawdatasize - tif->tif_rawcc;
482	for (i = npixels; i--; ) {
483		if (occ < 3) {
484			tif->tif_rawcp = op;
485			tif->tif_rawcc = tif->tif_rawdatasize - occ;
486			if (!TIFFFlushData1(tif))
487				return (-1);
488			op = tif->tif_rawcp;
489			occ = tif->tif_rawdatasize - tif->tif_rawcc;
490		}
491		*op++ = (tidataval_t)(*tp >> 16);
492		*op++ = (tidataval_t)(*tp >> 8 & 0xff);
493		*op++ = (tidataval_t)(*tp++ & 0xff);
494		occ -= 3;
495	}
496	tif->tif_rawcp = op;
497	tif->tif_rawcc = tif->tif_rawdatasize - occ;
498
499	return (0);
500}
501
502/*
503 * Encode a row of 32-bit pixels.
504 */
505static int
506LogLuvEncode32(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
507{
508	LogLuvState* sp = EncoderState(tif);
509	int shft, i, j, npixels;
510	tidata_t op;
511	uint32* tp;
512	uint32 b;
513	int occ, rc=0, mask, beg;
514
515	assert(s == 0);
516	assert(sp != NULL);
517
518	npixels = cc / sp->pixel_size;
519
520	if (sp->user_datafmt == SGILOGDATAFMT_RAW)
521		tp = (uint32*) bp;
522	else {
523		tp = (uint32*) sp->tbuf;
524		assert(sp->tbuflen >= npixels);
525		(*sp->tfunc)(sp, bp, npixels);
526	}
527					/* compress each byte string */
528	op = tif->tif_rawcp;
529	occ = tif->tif_rawdatasize - tif->tif_rawcc;
530	for (shft = 4*8; (shft -= 8) >= 0; )
531		for (i = 0; i < npixels; i += rc) {
532			if (occ < 4) {
533				tif->tif_rawcp = op;
534				tif->tif_rawcc = tif->tif_rawdatasize - occ;
535				if (!TIFFFlushData1(tif))
536					return (-1);
537				op = tif->tif_rawcp;
538				occ = tif->tif_rawdatasize - tif->tif_rawcc;
539			}
540			mask = 0xff << shft;		/* find next run */
541			for (beg = i; beg < npixels; beg += rc) {
542				b = tp[beg] & mask;
543				rc = 1;
544				while (rc < 127+2 && beg+rc < npixels &&
545						(tp[beg+rc] & mask) == b)
546					rc++;
547				if (rc >= MINRUN)
548					break;		/* long enough */
549			}
550			if (beg-i > 1 && beg-i < MINRUN) {
551				b = tp[i] & mask;	/* check short run */
552				j = i+1;
553				while ((tp[j++] & mask) == b)
554					if (j == beg) {
555						*op++ = (tidataval_t)(128-2+j-i);
556						*op++ = (tidataval_t)(b >> shft);
557						occ -= 2;
558						i = beg;
559						break;
560					}
561			}
562			while (i < beg) {		/* write out non-run */
563				if ((j = beg-i) > 127) j = 127;
564				if (occ < j+3) {
565					tif->tif_rawcp = op;
566					tif->tif_rawcc = tif->tif_rawdatasize - occ;
567					if (!TIFFFlushData1(tif))
568						return (-1);
569					op = tif->tif_rawcp;
570					occ = tif->tif_rawdatasize - tif->tif_rawcc;
571				}
572				*op++ = (tidataval_t) j; occ--;
573				while (j--) {
574					*op++ = (tidataval_t)(tp[i++] >> shft & 0xff);
575					occ--;
576				}
577			}
578			if (rc >= MINRUN) {		/* write out run */
579				*op++ = (tidataval_t) (128-2+rc);
580				*op++ = (tidataval_t)(tp[beg] >> shft & 0xff);
581				occ -= 2;
582			} else
583				rc = 0;
584		}
585	tif->tif_rawcp = op;
586	tif->tif_rawcc = tif->tif_rawdatasize - occ;
587
588	return (0);
589}
590
591/*
592 * Encode a strip of pixels.  We break it into rows to
593 * avoid encoding runs across row boundaries.
594 */
595static int
596LogLuvEncodeStrip(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
597{
598	tsize_t rowlen = TIFFScanlineSize(tif);
599
600	assert(cc%rowlen == 0);
601	while (cc && (*tif->tif_encoderow)(tif, bp, rowlen, s) == 0)
602		bp += rowlen, cc -= rowlen;
603	return (cc == 0);
604}
605
606/*
607 * Encode a tile of pixels.  We break it into rows to
608 * avoid encoding runs across row boundaries.
609 */
610static int
611LogLuvEncodeTile(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
612{
613	tsize_t rowlen = TIFFTileRowSize(tif);
614
615	assert(cc%rowlen == 0);
616	while (cc && (*tif->tif_encoderow)(tif, bp, rowlen, s) == 0)
617		bp += rowlen, cc -= rowlen;
618	return (cc == 0);
619}
620
621/*
622 * Encode/Decode functions for converting to and from user formats.
623 */
624
625#include "uvcode.h"
626
627#ifndef UVSCALE
628#define U_NEU		0.210526316
629#define V_NEU		0.473684211
630#define UVSCALE		410.
631#endif
632
633#ifndef	M_LN2
634#define M_LN2		0.69314718055994530942
635#endif
636#ifndef M_PI
637#define M_PI		3.14159265358979323846
638#endif
639#define log2(x)		((1./M_LN2)*log(x))
640#define exp2(x)		exp(M_LN2*(x))
641
642#define itrunc(x,m)	((m)==SGILOGENCODE_NODITHER ? \
643				(int)(x) : \
644				(int)((x) + rand()*(1./RAND_MAX) - .5))
645
646#if !LOGLUV_PUBLIC
647static
648#endif
649double
650LogL16toY(int p16)		/* compute luminance from 16-bit LogL */
651{
652	int	Le = p16 & 0x7fff;
653	double	Y;
654
655	if (!Le)
656		return (0.);
657	Y = exp(M_LN2/256.*(Le+.5) - M_LN2*64.);
658	return (!(p16 & 0x8000) ? Y : -Y);
659}
660
661#if !LOGLUV_PUBLIC
662static
663#endif
664int
665LogL16fromY(double Y, int em)	/* get 16-bit LogL from Y */
666{
667	if (Y >= 1.8371976e19)
668		return (0x7fff);
669	if (Y <= -1.8371976e19)
670		return (0xffff);
671	if (Y > 5.4136769e-20)
672		return itrunc(256.*(log2(Y) + 64.), em);
673	if (Y < -5.4136769e-20)
674		return (~0x7fff | itrunc(256.*(log2(-Y) + 64.), em));
675	return (0);
676}
677
678static void
679L16toY(LogLuvState* sp, tidata_t op, int n)
680{
681	int16* l16 = (int16*) sp->tbuf;
682	float* yp = (float*) op;
683
684	while (n-- > 0)
685		*yp++ = (float)LogL16toY(*l16++);
686}
687
688static void
689L16toGry(LogLuvState* sp, tidata_t op, int n)
690{
691	int16* l16 = (int16*) sp->tbuf;
692	uint8* gp = (uint8*) op;
693
694	while (n-- > 0) {
695		double Y = LogL16toY(*l16++);
696		*gp++ = (uint8) ((Y <= 0.) ? 0 : (Y >= 1.) ? 255 : (int)(256.*sqrt(Y)));
697	}
698}
699
700static void
701L16fromY(LogLuvState* sp, tidata_t op, int n)
702{
703	int16* l16 = (int16*) sp->tbuf;
704	float* yp = (float*) op;
705
706	while (n-- > 0)
707		*l16++ = (int16) (LogL16fromY(*yp++, sp->encode_meth));
708}
709
710#if !LOGLUV_PUBLIC
711static
712#endif
713void
714XYZtoRGB24(float xyz[3], uint8 rgb[3])
715{
716	double	r, g, b;
717					/* assume CCIR-709 primaries */
718	r =  2.690*xyz[0] + -1.276*xyz[1] + -0.414*xyz[2];
719	g = -1.022*xyz[0] +  1.978*xyz[1] +  0.044*xyz[2];
720	b =  0.061*xyz[0] + -0.224*xyz[1] +  1.163*xyz[2];
721					/* assume 2.0 gamma for speed */
722	/* could use integer sqrt approx., but this is probably faster */
723	rgb[0] = (uint8)((r<=0.) ? 0 : (r >= 1.) ? 255 : (int)(256.*sqrt(r)));
724	rgb[1] = (uint8)((g<=0.) ? 0 : (g >= 1.) ? 255 : (int)(256.*sqrt(g)));
725	rgb[2] = (uint8)((b<=0.) ? 0 : (b >= 1.) ? 255 : (int)(256.*sqrt(b)));
726}
727
728#if !LOGLUV_PUBLIC
729static
730#endif
731double
732LogL10toY(int p10)		/* compute luminance from 10-bit LogL */
733{
734	if (p10 == 0)
735		return (0.);
736	return (exp(M_LN2/64.*(p10+.5) - M_LN2*12.));
737}
738
739#if !LOGLUV_PUBLIC
740static
741#endif
742int
743LogL10fromY(double Y, int em)	/* get 10-bit LogL from Y */
744{
745	if (Y >= 15.742)
746		return (0x3ff);
747	else if (Y <= .00024283)
748		return (0);
749	else
750		return itrunc(64.*(log2(Y) + 12.), em);
751}
752
753#define NANGLES		100
754#define uv2ang(u, v)	( (NANGLES*.499999999/M_PI) \
755				* atan2((v)-V_NEU,(u)-U_NEU) + .5*NANGLES )
756
757static int
758oog_encode(double u, double v)		/* encode out-of-gamut chroma */
759{
760	static int	oog_table[NANGLES];
761	static int	initialized = 0;
762	register int	i;
763
764	if (!initialized) {		/* set up perimeter table */
765		double	eps[NANGLES], ua, va, ang, epsa;
766		int	ui, vi, ustep;
767		for (i = NANGLES; i--; )
768			eps[i] = 2.;
769		for (vi = UV_NVS; vi--; ) {
770			va = UV_VSTART + (vi+.5)*UV_SQSIZ;
771			ustep = uv_row[vi].nus-1;
772			if (vi == UV_NVS-1 || vi == 0 || ustep <= 0)
773				ustep = 1;
774			for (ui = uv_row[vi].nus-1; ui >= 0; ui -= ustep) {
775				ua = uv_row[vi].ustart + (ui+.5)*UV_SQSIZ;
776				ang = uv2ang(ua, va);
777                                i = (int) ang;
778				epsa = fabs(ang - (i+.5));
779				if (epsa < eps[i]) {
780					oog_table[i] = uv_row[vi].ncum + ui;
781					eps[i] = epsa;
782				}
783			}
784		}
785		for (i = NANGLES; i--; )	/* fill any holes */
786			if (eps[i] > 1.5) {
787				int	i1, i2;
788				for (i1 = 1; i1 < NANGLES/2; i1++)
789					if (eps[(i+i1)%NANGLES] < 1.5)
790						break;
791				for (i2 = 1; i2 < NANGLES/2; i2++)
792					if (eps[(i+NANGLES-i2)%NANGLES] < 1.5)
793						break;
794				if (i1 < i2)
795					oog_table[i] =
796						oog_table[(i+i1)%NANGLES];
797				else
798					oog_table[i] =
799						oog_table[(i+NANGLES-i2)%NANGLES];
800			}
801		initialized = 1;
802	}
803	i = (int) uv2ang(u, v);		/* look up hue angle */
804	return (oog_table[i]);
805}
806
807#undef uv2ang
808#undef NANGLES
809
810#if !LOGLUV_PUBLIC
811static
812#endif
813int
814uv_encode(double u, double v, int em)	/* encode (u',v') coordinates */
815{
816	register int	vi, ui;
817
818	if (v < UV_VSTART)
819		return oog_encode(u, v);
820	vi = itrunc((v - UV_VSTART)*(1./UV_SQSIZ), em);
821	if (vi >= UV_NVS)
822		return oog_encode(u, v);
823	if (u < uv_row[vi].ustart)
824		return oog_encode(u, v);
825	ui = itrunc((u - uv_row[vi].ustart)*(1./UV_SQSIZ), em);
826	if (ui >= uv_row[vi].nus)
827		return oog_encode(u, v);
828
829	return (uv_row[vi].ncum + ui);
830}
831
832#if !LOGLUV_PUBLIC
833static
834#endif
835int
836uv_decode(double *up, double *vp, int c)	/* decode (u',v') index */
837{
838	int	upper, lower;
839	register int	ui, vi;
840
841	if (c < 0 || c >= UV_NDIVS)
842		return (-1);
843	lower = 0;				/* binary search */
844	upper = UV_NVS;
845	while (upper - lower > 1) {
846		vi = (lower + upper) >> 1;
847		ui = c - uv_row[vi].ncum;
848		if (ui > 0)
849			lower = vi;
850		else if (ui < 0)
851			upper = vi;
852		else {
853			lower = vi;
854			break;
855		}
856	}
857	vi = lower;
858	ui = c - uv_row[vi].ncum;
859	*up = uv_row[vi].ustart + (ui+.5)*UV_SQSIZ;
860	*vp = UV_VSTART + (vi+.5)*UV_SQSIZ;
861	return (0);
862}
863
864#if !LOGLUV_PUBLIC
865static
866#endif
867void
868LogLuv24toXYZ(uint32 p, float XYZ[3])
869{
870	int	Ce;
871	double	L, u, v, s, x, y;
872					/* decode luminance */
873	L = LogL10toY(p>>14 & 0x3ff);
874	if (L <= 0.) {
875		XYZ[0] = XYZ[1] = XYZ[2] = 0.;
876		return;
877	}
878					/* decode color */
879	Ce = p & 0x3fff;
880	if (uv_decode(&u, &v, Ce) < 0) {
881		u = U_NEU; v = V_NEU;
882	}
883	s = 1./(6.*u - 16.*v + 12.);
884	x = 9.*u * s;
885	y = 4.*v * s;
886					/* convert to XYZ */
887	XYZ[0] = (float)(x/y * L);
888	XYZ[1] = (float)L;
889	XYZ[2] = (float)((1.-x-y)/y * L);
890}
891
892#if !LOGLUV_PUBLIC
893static
894#endif
895uint32
896LogLuv24fromXYZ(float XYZ[3], int em)
897{
898	int	Le, Ce;
899	double	u, v, s;
900					/* encode luminance */
901	Le = LogL10fromY(XYZ[1], em);
902					/* encode color */
903	s = XYZ[0] + 15.*XYZ[1] + 3.*XYZ[2];
904	if (!Le || s <= 0.) {
905		u = U_NEU;
906		v = V_NEU;
907	} else {
908		u = 4.*XYZ[0] / s;
909		v = 9.*XYZ[1] / s;
910	}
911	Ce = uv_encode(u, v, em);
912	if (Ce < 0)			/* never happens */
913		Ce = uv_encode(U_NEU, V_NEU, SGILOGENCODE_NODITHER);
914					/* combine encodings */
915	return (Le << 14 | Ce);
916}
917
918static void
919Luv24toXYZ(LogLuvState* sp, tidata_t op, int n)
920{
921	uint32* luv = (uint32*) sp->tbuf;
922	float* xyz = (float*) op;
923
924	while (n-- > 0) {
925		LogLuv24toXYZ(*luv, xyz);
926		xyz += 3;
927		luv++;
928	}
929}
930
931static void
932Luv24toLuv48(LogLuvState* sp, tidata_t op, int n)
933{
934	uint32* luv = (uint32*) sp->tbuf;
935	int16* luv3 = (int16*) op;
936
937	while (n-- > 0) {
938		double u, v;
939
940		*luv3++ = (int16)((*luv >> 12 & 0xffd) + 13314);
941		if (uv_decode(&u, &v, *luv&0x3fff) < 0) {
942			u = U_NEU;
943			v = V_NEU;
944		}
945		*luv3++ = (int16)(u * (1L<<15));
946		*luv3++ = (int16)(v * (1L<<15));
947		luv++;
948	}
949}
950
951static void
952Luv24toRGB(LogLuvState* sp, tidata_t op, int n)
953{
954	uint32* luv = (uint32*) sp->tbuf;
955	uint8* rgb = (uint8*) op;
956
957	while (n-- > 0) {
958		float xyz[3];
959
960		LogLuv24toXYZ(*luv++, xyz);
961		XYZtoRGB24(xyz, rgb);
962		rgb += 3;
963	}
964}
965
966static void
967Luv24fromXYZ(LogLuvState* sp, tidata_t op, int n)
968{
969	uint32* luv = (uint32*) sp->tbuf;
970	float* xyz = (float*) op;
971
972	while (n-- > 0) {
973		*luv++ = LogLuv24fromXYZ(xyz, sp->encode_meth);
974		xyz += 3;
975	}
976}
977
978static void
979Luv24fromLuv48(LogLuvState* sp, tidata_t op, int n)
980{
981	uint32* luv = (uint32*) sp->tbuf;
982	int16* luv3 = (int16*) op;
983
984	while (n-- > 0) {
985		int Le, Ce;
986
987		if (luv3[0] <= 0)
988			Le = 0;
989		else if (luv3[0] >= (1<<12)+3314)
990			Le = (1<<10) - 1;
991		else if (sp->encode_meth == SGILOGENCODE_NODITHER)
992			Le = (luv3[0]-3314) >> 2;
993		else
994			Le = itrunc(.25*(luv3[0]-3314.), sp->encode_meth);
995
996		Ce = uv_encode((luv3[1]+.5)/(1<<15), (luv3[2]+.5)/(1<<15),
997					sp->encode_meth);
998		if (Ce < 0)	/* never happens */
999			Ce = uv_encode(U_NEU, V_NEU, SGILOGENCODE_NODITHER);
1000		*luv++ = (uint32)Le << 14 | Ce;
1001		luv3 += 3;
1002	}
1003}
1004
1005#if !LOGLUV_PUBLIC
1006static
1007#endif
1008void
1009LogLuv32toXYZ(uint32 p, float XYZ[3])
1010{
1011	double	L, u, v, s, x, y;
1012					/* decode luminance */
1013	L = LogL16toY((int)p >> 16);
1014	if (L <= 0.) {
1015		XYZ[0] = XYZ[1] = XYZ[2] = 0.;
1016		return;
1017	}
1018					/* decode color */
1019	u = 1./UVSCALE * ((p>>8 & 0xff) + .5);
1020	v = 1./UVSCALE * ((p & 0xff) + .5);
1021	s = 1./(6.*u - 16.*v + 12.);
1022	x = 9.*u * s;
1023	y = 4.*v * s;
1024					/* convert to XYZ */
1025	XYZ[0] = (float)(x/y * L);
1026	XYZ[1] = (float)L;
1027	XYZ[2] = (float)((1.-x-y)/y * L);
1028}
1029
1030#if !LOGLUV_PUBLIC
1031static
1032#endif
1033uint32
1034LogLuv32fromXYZ(float XYZ[3], int em)
1035{
1036	unsigned int	Le, ue, ve;
1037	double	u, v, s;
1038					/* encode luminance */
1039	Le = (unsigned int)LogL16fromY(XYZ[1], em);
1040					/* encode color */
1041	s = XYZ[0] + 15.*XYZ[1] + 3.*XYZ[2];
1042	if (!Le || s <= 0.) {
1043		u = U_NEU;
1044		v = V_NEU;
1045	} else {
1046		u = 4.*XYZ[0] / s;
1047		v = 9.*XYZ[1] / s;
1048	}
1049	if (u <= 0.) ue = 0;
1050	else ue = itrunc(UVSCALE*u, em);
1051	if (ue > 255) ue = 255;
1052	if (v <= 0.) ve = 0;
1053	else ve = itrunc(UVSCALE*v, em);
1054	if (ve > 255) ve = 255;
1055					/* combine encodings */
1056	return (Le << 16 | ue << 8 | ve);
1057}
1058
1059static void
1060Luv32toXYZ(LogLuvState* sp, tidata_t op, int n)
1061{
1062	uint32* luv = (uint32*) sp->tbuf;
1063	float* xyz = (float*) op;
1064
1065	while (n-- > 0) {
1066		LogLuv32toXYZ(*luv++, xyz);
1067		xyz += 3;
1068	}
1069}
1070
1071static void
1072Luv32toLuv48(LogLuvState* sp, tidata_t op, int n)
1073{
1074	uint32* luv = (uint32*) sp->tbuf;
1075	int16* luv3 = (int16*) op;
1076
1077	while (n-- > 0) {
1078		double u, v;
1079
1080		*luv3++ = (int16)(*luv >> 16);
1081		u = 1./UVSCALE * ((*luv>>8 & 0xff) + .5);
1082		v = 1./UVSCALE * ((*luv & 0xff) + .5);
1083		*luv3++ = (int16)(u * (1L<<15));
1084		*luv3++ = (int16)(v * (1L<<15));
1085		luv++;
1086	}
1087}
1088
1089static void
1090Luv32toRGB(LogLuvState* sp, tidata_t op, int n)
1091{
1092	uint32* luv = (uint32*) sp->tbuf;
1093	uint8* rgb = (uint8*) op;
1094
1095	while (n-- > 0) {
1096		float xyz[3];
1097
1098		LogLuv32toXYZ(*luv++, xyz);
1099		XYZtoRGB24(xyz, rgb);
1100		rgb += 3;
1101	}
1102}
1103
1104static void
1105Luv32fromXYZ(LogLuvState* sp, tidata_t op, int n)
1106{
1107	uint32* luv = (uint32*) sp->tbuf;
1108	float* xyz = (float*) op;
1109
1110	while (n-- > 0) {
1111		*luv++ = LogLuv32fromXYZ(xyz, sp->encode_meth);
1112		xyz += 3;
1113	}
1114}
1115
1116static void
1117Luv32fromLuv48(LogLuvState* sp, tidata_t op, int n)
1118{
1119	uint32* luv = (uint32*) sp->tbuf;
1120	int16* luv3 = (int16*) op;
1121
1122	if (sp->encode_meth == SGILOGENCODE_NODITHER) {
1123		while (n-- > 0) {
1124			*luv++ = (uint32)luv3[0] << 16 |
1125				(luv3[1]*(uint32)(UVSCALE+.5) >> 7 & 0xff00) |
1126				(luv3[2]*(uint32)(UVSCALE+.5) >> 15 & 0xff);
1127			luv3 += 3;
1128		}
1129		return;
1130	}
1131	while (n-- > 0) {
1132		*luv++ = (uint32)luv3[0] << 16 |
1133	(itrunc(luv3[1]*(UVSCALE/(1<<15)), sp->encode_meth) << 8 & 0xff00) |
1134		(itrunc(luv3[2]*(UVSCALE/(1<<15)), sp->encode_meth) & 0xff);
1135		luv3 += 3;
1136	}
1137}
1138
1139static void
1140_logLuvNop(LogLuvState* sp, tidata_t op, int n)
1141{
1142	(void) sp; (void) op; (void) n;
1143}
1144
1145static int
1146LogL16GuessDataFmt(TIFFDirectory *td)
1147{
1148#define	PACK(s,b,f)	(((b)<<6)|((s)<<3)|(f))
1149	switch (PACK(td->td_samplesperpixel, td->td_bitspersample, td->td_sampleformat)) {
1150	case PACK(1, 32, SAMPLEFORMAT_IEEEFP):
1151		return (SGILOGDATAFMT_FLOAT);
1152	case PACK(1, 16, SAMPLEFORMAT_VOID):
1153	case PACK(1, 16, SAMPLEFORMAT_INT):
1154	case PACK(1, 16, SAMPLEFORMAT_UINT):
1155		return (SGILOGDATAFMT_16BIT);
1156	case PACK(1,  8, SAMPLEFORMAT_VOID):
1157	case PACK(1,  8, SAMPLEFORMAT_UINT):
1158		return (SGILOGDATAFMT_8BIT);
1159	}
1160#undef PACK
1161	return (SGILOGDATAFMT_UNKNOWN);
1162}
1163
1164static uint32
1165multiply(size_t m1, size_t m2)
1166{
1167	uint32	bytes = m1 * m2;
1168
1169	if (m1 && bytes / m1 != m2)
1170		bytes = 0;
1171
1172	return bytes;
1173}
1174
1175static int
1176LogL16InitState(TIFF* tif)
1177{
1178	TIFFDirectory *td = &tif->tif_dir;
1179	LogLuvState* sp = DecoderState(tif);
1180	static const char module[] = "LogL16InitState";
1181
1182	assert(sp != NULL);
1183	assert(td->td_photometric == PHOTOMETRIC_LOGL);
1184
1185	/* for some reason, we can't do this in TIFFInitLogL16 */
1186	if (sp->user_datafmt == SGILOGDATAFMT_UNKNOWN)
1187		sp->user_datafmt = LogL16GuessDataFmt(td);
1188	switch (sp->user_datafmt) {
1189	case SGILOGDATAFMT_FLOAT:
1190		sp->pixel_size = sizeof (float);
1191		break;
1192	case SGILOGDATAFMT_16BIT:
1193		sp->pixel_size = sizeof (int16);
1194		break;
1195	case SGILOGDATAFMT_8BIT:
1196		sp->pixel_size = sizeof (uint8);
1197		break;
1198	default:
1199		TIFFError(tif->tif_name,
1200		    "No support for converting user data format to LogL");
1201		return (0);
1202	}
1203	sp->tbuflen = multiply(td->td_imagewidth, td->td_rowsperstrip);
1204	if (multiply(sp->tbuflen, sizeof (int16)) == 0 ||
1205	    (sp->tbuf = (tidata_t*) _TIFFmalloc(sp->tbuflen * sizeof (int16))) == NULL) {
1206		TIFFError(module, "%s: No space for SGILog translation buffer",
1207		    tif->tif_name);
1208		return (0);
1209	}
1210	return (1);
1211}
1212
1213static int
1214LogLuvGuessDataFmt(TIFFDirectory *td)
1215{
1216	int guess;
1217
1218	/*
1219	 * If the user didn't tell us their datafmt,
1220	 * take our best guess from the bitspersample.
1221	 */
1222#define	PACK(a,b)	(((a)<<3)|(b))
1223	switch (PACK(td->td_bitspersample, td->td_sampleformat)) {
1224	case PACK(32, SAMPLEFORMAT_IEEEFP):
1225		guess = SGILOGDATAFMT_FLOAT;
1226		break;
1227	case PACK(32, SAMPLEFORMAT_VOID):
1228	case PACK(32, SAMPLEFORMAT_UINT):
1229	case PACK(32, SAMPLEFORMAT_INT):
1230		guess = SGILOGDATAFMT_RAW;
1231		break;
1232	case PACK(16, SAMPLEFORMAT_VOID):
1233	case PACK(16, SAMPLEFORMAT_INT):
1234	case PACK(16, SAMPLEFORMAT_UINT):
1235		guess = SGILOGDATAFMT_16BIT;
1236		break;
1237	case PACK( 8, SAMPLEFORMAT_VOID):
1238	case PACK( 8, SAMPLEFORMAT_UINT):
1239		guess = SGILOGDATAFMT_8BIT;
1240		break;
1241	default:
1242		guess = SGILOGDATAFMT_UNKNOWN;
1243		break;
1244#undef PACK
1245	}
1246	/*
1247	 * Double-check samples per pixel.
1248	 */
1249	switch (td->td_samplesperpixel) {
1250	case 1:
1251		if (guess != SGILOGDATAFMT_RAW)
1252			guess = SGILOGDATAFMT_UNKNOWN;
1253		break;
1254	case 3:
1255		if (guess == SGILOGDATAFMT_RAW)
1256			guess = SGILOGDATAFMT_UNKNOWN;
1257		break;
1258	default:
1259		guess = SGILOGDATAFMT_UNKNOWN;
1260		break;
1261	}
1262	return (guess);
1263}
1264
1265static int
1266LogLuvInitState(TIFF* tif)
1267{
1268	TIFFDirectory* td = &tif->tif_dir;
1269	LogLuvState* sp = DecoderState(tif);
1270	static const char module[] = "LogLuvInitState";
1271
1272	assert(sp != NULL);
1273	assert(td->td_photometric == PHOTOMETRIC_LOGLUV);
1274
1275	/* for some reason, we can't do this in TIFFInitLogLuv */
1276	if (td->td_planarconfig != PLANARCONFIG_CONTIG) {
1277		TIFFError(module,
1278		    "SGILog compression cannot handle non-contiguous data");
1279		return (0);
1280	}
1281	if (sp->user_datafmt == SGILOGDATAFMT_UNKNOWN)
1282		sp->user_datafmt = LogLuvGuessDataFmt(td);
1283	switch (sp->user_datafmt) {
1284	case SGILOGDATAFMT_FLOAT:
1285		sp->pixel_size = 3*sizeof (float);
1286		break;
1287	case SGILOGDATAFMT_16BIT:
1288		sp->pixel_size = 3*sizeof (int16);
1289		break;
1290	case SGILOGDATAFMT_RAW:
1291		sp->pixel_size = sizeof (uint32);
1292		break;
1293	case SGILOGDATAFMT_8BIT:
1294		sp->pixel_size = 3*sizeof (uint8);
1295		break;
1296	default:
1297		TIFFError(tif->tif_name,
1298		    "No support for converting user data format to LogLuv");
1299		return (0);
1300	}
1301	sp->tbuflen = multiply(td->td_imagewidth, td->td_rowsperstrip);
1302	if (multiply(sp->tbuflen, sizeof (uint32)) == 0 ||
1303	    (sp->tbuf = (tidata_t*) _TIFFmalloc(sp->tbuflen * sizeof (uint32))) == NULL) {
1304		TIFFError(module, "%s: No space for SGILog translation buffer",
1305		    tif->tif_name);
1306		return (0);
1307	}
1308	return (1);
1309}
1310
1311static int
1312LogLuvSetupDecode(TIFF* tif)
1313{
1314	LogLuvState* sp = DecoderState(tif);
1315	TIFFDirectory* td = &tif->tif_dir;
1316
1317	tif->tif_postdecode = _TIFFNoPostDecode;
1318	switch (td->td_photometric) {
1319	case PHOTOMETRIC_LOGLUV:
1320		if (!LogLuvInitState(tif))
1321			break;
1322		if (td->td_compression == COMPRESSION_SGILOG24) {
1323			tif->tif_decoderow = LogLuvDecode24;
1324			switch (sp->user_datafmt) {
1325			case SGILOGDATAFMT_FLOAT:
1326				sp->tfunc = Luv24toXYZ;
1327				break;
1328			case SGILOGDATAFMT_16BIT:
1329				sp->tfunc = Luv24toLuv48;
1330				break;
1331			case SGILOGDATAFMT_8BIT:
1332				sp->tfunc = Luv24toRGB;
1333				break;
1334			}
1335		} else {
1336			tif->tif_decoderow = LogLuvDecode32;
1337			switch (sp->user_datafmt) {
1338			case SGILOGDATAFMT_FLOAT:
1339				sp->tfunc = Luv32toXYZ;
1340				break;
1341			case SGILOGDATAFMT_16BIT:
1342				sp->tfunc = Luv32toLuv48;
1343				break;
1344			case SGILOGDATAFMT_8BIT:
1345				sp->tfunc = Luv32toRGB;
1346				break;
1347			}
1348		}
1349		return (1);
1350	case PHOTOMETRIC_LOGL:
1351		if (!LogL16InitState(tif))
1352			break;
1353		tif->tif_decoderow = LogL16Decode;
1354		switch (sp->user_datafmt) {
1355		case SGILOGDATAFMT_FLOAT:
1356			sp->tfunc = L16toY;
1357			break;
1358		case SGILOGDATAFMT_8BIT:
1359			sp->tfunc = L16toGry;
1360			break;
1361		}
1362		return (1);
1363	default:
1364		TIFFError(tif->tif_name,
1365    "Inappropriate photometric interpretation %d for SGILog compression; %s",
1366		    td->td_photometric, "must be either LogLUV or LogL");
1367		break;
1368	}
1369	return (0);
1370}
1371
1372static int
1373LogLuvSetupEncode(TIFF* tif)
1374{
1375	LogLuvState* sp = EncoderState(tif);
1376	TIFFDirectory* td = &tif->tif_dir;
1377
1378	switch (td->td_photometric) {
1379	case PHOTOMETRIC_LOGLUV:
1380		if (!LogLuvInitState(tif))
1381			break;
1382		if (td->td_compression == COMPRESSION_SGILOG24) {
1383			tif->tif_encoderow = LogLuvEncode24;
1384			switch (sp->user_datafmt) {
1385			case SGILOGDATAFMT_FLOAT:
1386				sp->tfunc = Luv24fromXYZ;
1387				break;
1388			case SGILOGDATAFMT_16BIT:
1389				sp->tfunc = Luv24fromLuv48;
1390				break;
1391			case SGILOGDATAFMT_RAW:
1392				break;
1393			default:
1394				goto notsupported;
1395			}
1396		} else {
1397			tif->tif_encoderow = LogLuvEncode32;
1398			switch (sp->user_datafmt) {
1399			case SGILOGDATAFMT_FLOAT:
1400				sp->tfunc = Luv32fromXYZ;
1401				break;
1402			case SGILOGDATAFMT_16BIT:
1403				sp->tfunc = Luv32fromLuv48;
1404				break;
1405			case SGILOGDATAFMT_RAW:
1406				break;
1407			default:
1408				goto notsupported;
1409			}
1410		}
1411		break;
1412	case PHOTOMETRIC_LOGL:
1413		if (!LogL16InitState(tif))
1414			break;
1415		tif->tif_encoderow = LogL16Encode;
1416		switch (sp->user_datafmt) {
1417		case SGILOGDATAFMT_FLOAT:
1418			sp->tfunc = L16fromY;
1419			break;
1420		case SGILOGDATAFMT_16BIT:
1421			break;
1422		default:
1423			goto notsupported;
1424		}
1425		break;
1426	default:
1427		TIFFError(tif->tif_name,
1428    "Inappropriate photometric interpretation %d for SGILog compression; %s",
1429    		    td->td_photometric, "must be either LogLUV or LogL");
1430		break;
1431	}
1432	return (1);
1433notsupported:
1434	TIFFError(tif->tif_name,
1435	    "SGILog compression supported only for %s, or raw data",
1436	    td->td_photometric == PHOTOMETRIC_LOGL ? "Y, L" : "XYZ, Luv");
1437	return (0);
1438}
1439
1440static void
1441LogLuvClose(TIFF* tif)
1442{
1443	TIFFDirectory *td = &tif->tif_dir;
1444
1445	/*
1446	 * For consistency, we always want to write out the same
1447	 * bitspersample and sampleformat for our TIFF file,
1448	 * regardless of the data format being used by the application.
1449	 * Since this routine is called after tags have been set but
1450	 * before they have been recorded in the file, we reset them here.
1451	 */
1452	td->td_samplesperpixel =
1453	    (td->td_photometric == PHOTOMETRIC_LOGL) ? 1 : 3;
1454	td->td_bitspersample = 16;
1455	td->td_sampleformat = SAMPLEFORMAT_INT;
1456}
1457
1458static void
1459LogLuvCleanup(TIFF* tif)
1460{
1461	LogLuvState* sp = (LogLuvState *)tif->tif_data;
1462
1463	if (sp) {
1464		if (sp->tbuf)
1465			_TIFFfree(sp->tbuf);
1466		_TIFFfree(sp);
1467		tif->tif_data = NULL;
1468	}
1469}
1470
1471static int
1472LogLuvVSetField(TIFF* tif, ttag_t tag, va_list ap)
1473{
1474	LogLuvState* sp = DecoderState(tif);
1475	int bps, fmt;
1476
1477	switch (tag) {
1478	case TIFFTAG_SGILOGDATAFMT:
1479		sp->user_datafmt = va_arg(ap, int);
1480		/*
1481		 * Tweak the TIFF header so that the rest of libtiff knows what
1482		 * size of data will be passed between app and library, and
1483		 * assume that the app knows what it is doing and is not
1484		 * confused by these header manipulations...
1485		 */
1486		switch (sp->user_datafmt) {
1487		case SGILOGDATAFMT_FLOAT:
1488			bps = 32, fmt = SAMPLEFORMAT_IEEEFP;
1489			break;
1490		case SGILOGDATAFMT_16BIT:
1491			bps = 16, fmt = SAMPLEFORMAT_INT;
1492			break;
1493		case SGILOGDATAFMT_RAW:
1494			bps = 32, fmt = SAMPLEFORMAT_UINT;
1495			TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, 1);
1496			break;
1497		case SGILOGDATAFMT_8BIT:
1498			bps = 8, fmt = SAMPLEFORMAT_UINT;
1499			break;
1500		default:
1501			TIFFError(tif->tif_name,
1502			    "Unknown data format %d for LogLuv compression",
1503			    sp->user_datafmt);
1504			return (0);
1505		}
1506		TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, bps);
1507		TIFFSetField(tif, TIFFTAG_SAMPLEFORMAT, fmt);
1508		/*
1509		 * Must recalculate sizes should bits/sample change.
1510		 */
1511		tif->tif_tilesize = TIFFTileSize(tif);
1512		tif->tif_scanlinesize = TIFFScanlineSize(tif);
1513		return (1);
1514	case TIFFTAG_SGILOGENCODE:
1515		sp->encode_meth = va_arg(ap, int);
1516		if (sp->encode_meth != SGILOGENCODE_NODITHER &&
1517				sp->encode_meth != SGILOGENCODE_RANDITHER) {
1518			TIFFError(tif->tif_name,
1519				"Unknown encoding %d for LogLuv compression",
1520				sp->encode_meth);
1521			return (0);
1522		}
1523		return (1);
1524	default:
1525		return (*sp->vsetparent)(tif, tag, ap);
1526	}
1527}
1528
1529static int
1530LogLuvVGetField(TIFF* tif, ttag_t tag, va_list ap)
1531{
1532	LogLuvState *sp = (LogLuvState *)tif->tif_data;
1533
1534	switch (tag) {
1535	case TIFFTAG_SGILOGDATAFMT:
1536		*va_arg(ap, int*) = sp->user_datafmt;
1537		return (1);
1538	default:
1539		return (*sp->vgetparent)(tif, tag, ap);
1540	}
1541}
1542
1543static const TIFFFieldInfo LogLuvFieldInfo[] = {
1544    { TIFFTAG_SGILOGDATAFMT,	  0, 0,	TIFF_SHORT,	FIELD_PSEUDO,
1545      TRUE,	FALSE,	"SGILogDataFmt"},
1546    { TIFFTAG_SGILOGENCODE,	  0, 0, TIFF_SHORT,	FIELD_PSEUDO,
1547      TRUE,	FALSE,	"SGILogEncode"}
1548};
1549
1550int
1551TIFFInitSGILog(TIFF* tif, int scheme)
1552{
1553	static const char module[] = "TIFFInitSGILog";
1554	LogLuvState* sp;
1555
1556	assert(scheme == COMPRESSION_SGILOG24 || scheme == COMPRESSION_SGILOG);
1557
1558	/*
1559	 * Allocate state block so tag methods have storage to record values.
1560	 */
1561	tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (LogLuvState));
1562	if (tif->tif_data == NULL)
1563		goto bad;
1564	sp = (LogLuvState*) tif->tif_data;
1565	_TIFFmemset((tdata_t)sp, 0, sizeof (*sp));
1566	sp->user_datafmt = SGILOGDATAFMT_UNKNOWN;
1567	sp->encode_meth = (scheme == COMPRESSION_SGILOG24) ?
1568				SGILOGENCODE_RANDITHER : SGILOGENCODE_NODITHER;
1569	sp->tfunc = _logLuvNop;
1570
1571	/*
1572	 * Install codec methods.
1573	 * NB: tif_decoderow & tif_encoderow are filled
1574	 *     in at setup time.
1575	 */
1576	tif->tif_setupdecode = LogLuvSetupDecode;
1577	tif->tif_decodestrip = LogLuvDecodeStrip;
1578	tif->tif_decodetile = LogLuvDecodeTile;
1579	tif->tif_setupencode = LogLuvSetupEncode;
1580	tif->tif_encodestrip = LogLuvEncodeStrip;
1581	tif->tif_encodetile = LogLuvEncodeTile;
1582	tif->tif_close = LogLuvClose;
1583	tif->tif_cleanup = LogLuvCleanup;
1584
1585	/* override SetField so we can handle our private pseudo-tag */
1586	_TIFFMergeFieldInfo(tif, LogLuvFieldInfo, N(LogLuvFieldInfo));
1587	sp->vgetparent = tif->tif_tagmethods.vgetfield;
1588	tif->tif_tagmethods.vgetfield = LogLuvVGetField;   /* hook for codec tags */
1589	sp->vsetparent = tif->tif_tagmethods.vsetfield;
1590	tif->tif_tagmethods.vsetfield = LogLuvVSetField;   /* hook for codec tags */
1591
1592	return (1);
1593bad:
1594	TIFFError(module, "%s: No space for LogLuv state block", tif->tif_name);
1595	return (0);
1596}
1597#endif /* LOGLUV_SUPPORT */
1598