1 /* $Id: tif_luv.c,v 1.1 2005-06-17 13:54:52 vp153 Exp $ */
4 * Copyright (c) 1997 Greg Ward Larson
5 * Copyright (c) 1997 Silicon Graphics, Inc.
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, Greg Larson and Silicon Graphics may not be used in any
12 * advertising or publicity relating to the software without the specific,
13 * prior written permission of Sam Leffler, Greg Larson and Silicon Graphics.
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.
19 * IN NO EVENT SHALL SAM LEFFLER, GREG LARSON OR SILICON GRAPHICS BE LIABLE
20 * FOR 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
32 * LogLuv compression support for high dynamic range images.
34 * Contributed by Greg Larson.
36 * LogLuv image support uses the TIFF library to store 16 or 10-bit
37 * log luminance values with 8 bits each of u and v or a 14-bit index.
39 * The codec can take as input and produce as output 32-bit IEEE float values
40 * as well as 16-bit integer values. A 16-bit luminance is interpreted
41 * as a sign bit followed by a 15-bit integer that is converted
42 * to and from a linear magnitude using the transformation:
44 * L = 2^( (Le+.5)/256 - 64 ) # real from 15-bit
46 * Le = floor( 256*(log2(L) + 64) ) # 15-bit from real
48 * The actual conversion to world luminance units in candelas per sq. meter
49 * requires an additional multiplier, which is stored in the TIFFTAG_STONITS.
50 * This value is usually set such that a reasonable exposure comes from
51 * clamping decoded luminances above 1 to 1 in the displayed image.
53 * The 16-bit values for u and v may be converted to real values by dividing
54 * each by 32768. (This allows for negative values, which aren't useful as
55 * far as we know, but are left in case of future improvements in human
58 * Conversion from (u,v), which is actually the CIE (u',v') system for
59 * you color scientists, is accomplished by the following transformation:
61 * u = 4*x / (-2*x + 12*y + 3)
62 * v = 9*y / (-2*x + 12*y + 3)
64 * x = 9*u / (6*u - 16*v + 12)
65 * y = 4*v / (6*u - 16*v + 12)
67 * This process is greatly simplified by passing 32-bit IEEE floats
68 * for each of three CIE XYZ coordinates. The codec then takes care
69 * of conversion to and from LogLuv, though the application is still
70 * responsible for interpreting the TIFFTAG_STONITS calibration factor.
72 * By definition, a CIE XYZ vector of [1 1 1] corresponds to a neutral white
73 * point of (x,y)=(1/3,1/3). However, most color systems assume some other
74 * white point, such as D65, and an absolute color conversion to XYZ then
75 * to another color space with a different white point may introduce an
76 * unwanted color cast to the image. It is often desirable, therefore, to
77 * perform a white point conversion that maps the input white to [1 1 1]
78 * in XYZ, then record the original white point using the TIFFTAG_WHITEPOINT
79 * tag value. A decoder that demands absolute color calibration may use
80 * this white point tag to get back the original colors, but usually it
81 * will be ignored and the new white point will be used instead that
82 * matches the output color space.
84 * Pixel information is compressed into one of two basic encodings, depending
85 * on the setting of the compression tag, which is one of COMPRESSION_SGILOG
86 * or COMPRESSION_SGILOG24. For COMPRESSION_SGILOG, greyscale data is
92 * COMPRESSION_SGILOG color data is stored as:
95 * |-+---------------|--------+--------|
98 * For the 24-bit COMPRESSION_SGILOG24 color format, the data is stored as:
101 * |----------|--------------|
104 * There is no sign bit in the 24-bit case, and the (u,v) chromaticity is
105 * encoded as an index for optimal color resolution. The 10 log bits are
106 * defined by the following conversions:
108 * L = 2^((Le'+.5)/64 - 12) # real from 10-bit
110 * Le' = floor( 64*(log2(L) + 12) ) # 10-bit from real
112 * The 10 bits of the smaller format may be converted into the 15 bits of
113 * the larger format by multiplying by 4 and adding 13314. Obviously,
114 * a smaller range of magnitudes is covered (about 5 orders of magnitude
115 * instead of 38), and the lack of a sign bit means that negative luminances
116 * are not allowed. (Well, they aren't allowed in the real world, either,
117 * but they are useful for certain types of image processing.)
119 * The desired user format is controlled by the setting the internal
120 * pseudo tag TIFFTAG_SGILOGDATAFMT to one of:
121 * SGILOGDATAFMT_FLOAT = IEEE 32-bit float XYZ values
122 * SGILOGDATAFMT_16BIT = 16-bit integer encodings of logL, u and v
123 * Raw data i/o is also possible using:
124 * SGILOGDATAFMT_RAW = 32-bit unsigned integer with encoded pixel
125 * In addition, the following decoding is provided for ease of display:
126 * SGILOGDATAFMT_8BIT = 8-bit default RGB gamma-corrected values
128 * For grayscale images, we provide the following data formats:
129 * SGILOGDATAFMT_FLOAT = IEEE 32-bit float Y values
130 * SGILOGDATAFMT_16BIT = 16-bit integer w/ encoded luminance
131 * SGILOGDATAFMT_8BIT = 8-bit gray monitor values
133 * Note that the COMPRESSION_SGILOG applies a simple run-length encoding
134 * scheme by separating the logL, u and v bytes for each row and applying
135 * a PackBits type of compression. Since the 24-bit encoding is not
136 * adaptive, the 32-bit color format takes less space in many cases.
138 * Further control is provided over the conversion from higher-resolution
139 * formats to final encoded values through the pseudo tag
140 * TIFFTAG_SGILOGENCODE:
141 * SGILOGENCODE_NODITHER = do not dither encoded values
142 * SGILOGENCODE_RANDITHER = apply random dithering during encoding
144 * The default value of this tag is SGILOGENCODE_NODITHER for
145 * COMPRESSION_SGILOG to maximize run-length encoding and
146 * SGILOGENCODE_RANDITHER for COMPRESSION_SGILOG24 to turn
147 * quantization errors into noise.
155 * State block for each open TIFF
156 * file using LogLuv compression/decompression.
158 typedef struct logLuvState LogLuvState;
161 int user_datafmt; /* user data format */
162 int encode_meth; /* encoding method */
163 int pixel_size; /* bytes per pixel */
165 tidata_t* tbuf; /* translation buffer */
166 int tbuflen; /* buffer length */
167 void (*tfunc)(LogLuvState*, tidata_t, int);
169 TIFFVSetMethod vgetparent; /* super-class method */
170 TIFFVSetMethod vsetparent; /* super-class method */
173 #define DecoderState(tif) ((LogLuvState*) (tif)->tif_data)
174 #define EncoderState(tif) ((LogLuvState*) (tif)->tif_data)
176 #define N(a) (sizeof(a)/sizeof(a[0]))
177 #define SGILOGDATAFMT_UNKNOWN -1
179 #define MINRUN 4 /* minimum run length */
182 * Decode a string of 16-bit gray pixels.
185 LogL16Decode(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
187 LogLuvState* sp = DecoderState(tif);
188 int shft, i, npixels;
197 npixels = occ / sp->pixel_size;
199 if (sp->user_datafmt == SGILOGDATAFMT_16BIT)
202 assert(sp->tbuflen >= npixels);
203 tp = (int16*) sp->tbuf;
205 _TIFFmemset((tdata_t) tp, 0, npixels*sizeof (tp[0]));
207 bp = (unsigned char*) tif->tif_rawcp;
209 /* get each byte string */
210 for (shft = 2*8; (shft -= 8) >= 0; ) {
211 for (i = 0; i < npixels && cc > 0; )
212 if (*bp >= 128) { /* run */
213 rc = *bp++ + (2-128);
214 b = (int16)(*bp++ << shft);
216 while (rc-- && i < npixels)
218 } else { /* non-run */
219 rc = *bp++; /* nul is noop */
220 while (--cc && rc-- && i < npixels)
221 tp[i++] |= (int16)*bp++ << shft;
224 TIFFError(tif->tif_name,
225 "LogL16Decode: Not enough data at row %d (short %d pixels)",
226 tif->tif_row, npixels - i);
227 tif->tif_rawcp = (tidata_t) bp;
232 (*sp->tfunc)(sp, op, npixels);
233 tif->tif_rawcp = (tidata_t) bp;
239 * Decode a string of 24-bit pixels.
242 LogLuvDecode24(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
244 LogLuvState* sp = DecoderState(tif);
252 npixels = occ / sp->pixel_size;
254 if (sp->user_datafmt == SGILOGDATAFMT_RAW)
257 assert(sp->tbuflen >= npixels);
258 tp = (uint32 *) sp->tbuf;
260 /* copy to array of uint32 */
261 bp = (unsigned char*) tif->tif_rawcp;
263 for (i = 0; i < npixels && cc > 0; i++) {
264 tp[i] = bp[0] << 16 | bp[1] << 8 | bp[2];
268 tif->tif_rawcp = (tidata_t) bp;
271 TIFFError(tif->tif_name,
272 "LogLuvDecode24: Not enough data at row %d (short %d pixels)",
273 tif->tif_row, npixels - i);
276 (*sp->tfunc)(sp, op, npixels);
281 * Decode a string of 32-bit pixels.
284 LogLuvDecode32(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
287 int shft, i, npixels;
294 sp = DecoderState(tif);
297 npixels = occ / sp->pixel_size;
299 if (sp->user_datafmt == SGILOGDATAFMT_RAW)
302 assert(sp->tbuflen >= npixels);
303 tp = (uint32*) sp->tbuf;
305 _TIFFmemset((tdata_t) tp, 0, npixels*sizeof (tp[0]));
307 bp = (unsigned char*) tif->tif_rawcp;
309 /* get each byte string */
310 for (shft = 4*8; (shft -= 8) >= 0; ) {
311 for (i = 0; i < npixels && cc > 0; )
312 if (*bp >= 128) { /* run */
313 rc = *bp++ + (2-128);
314 b = (uint32)*bp++ << shft;
316 while (rc-- && i < npixels)
318 } else { /* non-run */
319 rc = *bp++; /* nul is noop */
320 while (--cc && rc-- && i < npixels)
321 tp[i++] |= (uint32)*bp++ << shft;
324 TIFFError(tif->tif_name,
325 "LogLuvDecode32: Not enough data at row %d (short %d pixels)",
326 tif->tif_row, npixels - i);
327 tif->tif_rawcp = (tidata_t) bp;
332 (*sp->tfunc)(sp, op, npixels);
333 tif->tif_rawcp = (tidata_t) bp;
339 * Decode a strip of pixels. We break it into rows to
340 * maintain synchrony with the encode algorithm, which
344 LogLuvDecodeStrip(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
346 tsize_t rowlen = TIFFScanlineSize(tif);
348 assert(cc%rowlen == 0);
349 while (cc && (*tif->tif_decoderow)(tif, bp, rowlen, s))
350 bp += rowlen, cc -= rowlen;
355 * Decode a tile of pixels. We break it into rows to
356 * maintain synchrony with the encode algorithm, which
360 LogLuvDecodeTile(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
362 tsize_t rowlen = TIFFTileRowSize(tif);
364 assert(cc%rowlen == 0);
365 while (cc && (*tif->tif_decoderow)(tif, bp, rowlen, s))
366 bp += rowlen, cc -= rowlen;
371 * Encode a row of 16-bit pixels.
374 LogL16Encode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
376 LogLuvState* sp = EncoderState(tif);
377 int shft, i, j, npixels;
381 int occ, rc=0, mask, beg;
385 npixels = cc / sp->pixel_size;
387 if (sp->user_datafmt == SGILOGDATAFMT_16BIT)
390 tp = (int16*) sp->tbuf;
391 assert(sp->tbuflen >= npixels);
392 (*sp->tfunc)(sp, bp, npixels);
394 /* compress each byte string */
396 occ = tif->tif_rawdatasize - tif->tif_rawcc;
397 for (shft = 2*8; (shft -= 8) >= 0; )
398 for (i = 0; i < npixels; i += rc) {
401 tif->tif_rawcc = tif->tif_rawdatasize - occ;
402 if (!TIFFFlushData1(tif))
405 occ = tif->tif_rawdatasize - tif->tif_rawcc;
407 mask = 0xff << shft; /* find next run */
408 for (beg = i; beg < npixels; beg += rc) {
409 b = (int16) (tp[beg] & mask);
411 while (rc < 127+2 && beg+rc < npixels &&
412 (tp[beg+rc] & mask) == b)
415 break; /* long enough */
417 if (beg-i > 1 && beg-i < MINRUN) {
418 b = (int16) (tp[i] & mask);/*check short run */
420 while ((tp[j++] & mask) == b)
422 *op++ = (tidataval_t)(128-2+j-i);
423 *op++ = (tidataval_t) (b >> shft);
429 while (i < beg) { /* write out non-run */
430 if ((j = beg-i) > 127) j = 127;
433 tif->tif_rawcc = tif->tif_rawdatasize - occ;
434 if (!TIFFFlushData1(tif))
437 occ = tif->tif_rawdatasize - tif->tif_rawcc;
439 *op++ = (tidataval_t) j; occ--;
441 *op++ = (tidataval_t) (tp[i++] >> shft & 0xff);
445 if (rc >= MINRUN) { /* write out run */
446 *op++ = (tidataval_t) (128-2+rc);
447 *op++ = (tidataval_t) (tp[beg] >> shft & 0xff);
453 tif->tif_rawcc = tif->tif_rawdatasize - occ;
459 * Encode a row of 24-bit pixels.
462 LogLuvEncode24(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
464 LogLuvState* sp = EncoderState(tif);
471 npixels = cc / sp->pixel_size;
473 if (sp->user_datafmt == SGILOGDATAFMT_RAW)
476 tp = (uint32*) sp->tbuf;
477 assert(sp->tbuflen >= npixels);
478 (*sp->tfunc)(sp, bp, npixels);
480 /* write out encoded pixels */
482 occ = tif->tif_rawdatasize - tif->tif_rawcc;
483 for (i = npixels; i--; ) {
486 tif->tif_rawcc = tif->tif_rawdatasize - occ;
487 if (!TIFFFlushData1(tif))
490 occ = tif->tif_rawdatasize - tif->tif_rawcc;
492 *op++ = (tidataval_t)(*tp >> 16);
493 *op++ = (tidataval_t)(*tp >> 8 & 0xff);
494 *op++ = (tidataval_t)(*tp++ & 0xff);
498 tif->tif_rawcc = tif->tif_rawdatasize - occ;
504 * Encode a row of 32-bit pixels.
507 LogLuvEncode32(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
509 LogLuvState* sp = EncoderState(tif);
510 int shft, i, j, npixels;
514 int occ, rc=0, mask, beg;
519 npixels = cc / sp->pixel_size;
521 if (sp->user_datafmt == SGILOGDATAFMT_RAW)
524 tp = (uint32*) sp->tbuf;
525 assert(sp->tbuflen >= npixels);
526 (*sp->tfunc)(sp, bp, npixels);
528 /* compress each byte string */
530 occ = tif->tif_rawdatasize - tif->tif_rawcc;
531 for (shft = 4*8; (shft -= 8) >= 0; )
532 for (i = 0; i < npixels; i += rc) {
535 tif->tif_rawcc = tif->tif_rawdatasize - occ;
536 if (!TIFFFlushData1(tif))
539 occ = tif->tif_rawdatasize - tif->tif_rawcc;
541 mask = 0xff << shft; /* find next run */
542 for (beg = i; beg < npixels; beg += rc) {
545 while (rc < 127+2 && beg+rc < npixels &&
546 (tp[beg+rc] & mask) == b)
549 break; /* long enough */
551 if (beg-i > 1 && beg-i < MINRUN) {
552 b = tp[i] & mask; /* check short run */
554 while ((tp[j++] & mask) == b)
556 *op++ = (tidataval_t)(128-2+j-i);
557 *op++ = (tidataval_t)(b >> shft);
563 while (i < beg) { /* write out non-run */
564 if ((j = beg-i) > 127) j = 127;
567 tif->tif_rawcc = tif->tif_rawdatasize - occ;
568 if (!TIFFFlushData1(tif))
571 occ = tif->tif_rawdatasize - tif->tif_rawcc;
573 *op++ = (tidataval_t) j; occ--;
575 *op++ = (tidataval_t)(tp[i++] >> shft & 0xff);
579 if (rc >= MINRUN) { /* write out run */
580 *op++ = (tidataval_t) (128-2+rc);
581 *op++ = (tidataval_t)(tp[beg] >> shft & 0xff);
587 tif->tif_rawcc = tif->tif_rawdatasize - occ;
593 * Encode a strip of pixels. We break it into rows to
594 * avoid encoding runs across row boundaries.
597 LogLuvEncodeStrip(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
599 tsize_t rowlen = TIFFScanlineSize(tif);
601 assert(cc%rowlen == 0);
602 while (cc && (*tif->tif_encoderow)(tif, bp, rowlen, s) == 0)
603 bp += rowlen, cc -= rowlen;
608 * Encode a tile of pixels. We break it into rows to
609 * avoid encoding runs across row boundaries.
612 LogLuvEncodeTile(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
614 tsize_t rowlen = TIFFTileRowSize(tif);
616 assert(cc%rowlen == 0);
617 while (cc && (*tif->tif_encoderow)(tif, bp, rowlen, s) == 0)
618 bp += rowlen, cc -= rowlen;
623 * Encode/Decode functions for converting to and from user formats.
629 #define U_NEU 0.210526316
630 #define V_NEU 0.473684211
635 #define M_LN2 0.69314718055994530942
638 #define M_PI 3.14159265358979323846
640 #define log2(x) ((1./M_LN2)*log(x))
641 #define exp2(x) exp(M_LN2*(x))
643 #define itrunc(x,m) ((m)==SGILOGENCODE_NODITHER ? \
645 (int)((x) + rand()*(1./RAND_MAX) - .5))
651 LogL16toY(int p16) /* compute luminance from 16-bit LogL */
653 int Le = p16 & 0x7fff;
658 Y = exp(M_LN2/256.*(Le+.5) - M_LN2*64.);
659 return (!(p16 & 0x8000) ? Y : -Y);
666 LogL16fromY(double Y, int em) /* get 16-bit LogL from Y */
668 if (Y >= 1.8371976e19)
670 if (Y <= -1.8371976e19)
672 if (Y > 5.4136769e-20)
673 return itrunc(256.*(log2(Y) + 64.), em);
674 if (Y < -5.4136769e-20)
675 return (~0x7fff | itrunc(256.*(log2(-Y) + 64.), em));
680 L16toY(LogLuvState* sp, tidata_t op, int n)
682 int16* l16 = (int16*) sp->tbuf;
683 float* yp = (float*) op;
686 *yp++ = (float)LogL16toY(*l16++);
690 L16toGry(LogLuvState* sp, tidata_t op, int n)
692 int16* l16 = (int16*) sp->tbuf;
693 uint8* gp = (uint8*) op;
696 double Y = LogL16toY(*l16++);
697 *gp++ = (uint8) ((Y <= 0.) ? 0 : (Y >= 1.) ? 255 : (int)(256.*sqrt(Y)));
702 L16fromY(LogLuvState* sp, tidata_t op, int n)
704 int16* l16 = (int16*) sp->tbuf;
705 float* yp = (float*) op;
708 *l16++ = (int16) (LogL16fromY(*yp++, sp->encode_meth));
715 XYZtoRGB24(float xyz[3], uint8 rgb[3])
718 /* assume CCIR-709 primaries */
719 r = 2.690*xyz[0] + -1.276*xyz[1] + -0.414*xyz[2];
720 g = -1.022*xyz[0] + 1.978*xyz[1] + 0.044*xyz[2];
721 b = 0.061*xyz[0] + -0.224*xyz[1] + 1.163*xyz[2];
722 /* assume 2.0 gamma for speed */
723 /* could use integer sqrt approx., but this is probably faster */
724 rgb[0] = (uint8)((r<=0.) ? 0 : (r >= 1.) ? 255 : (int)(256.*sqrt(r)));
725 rgb[1] = (uint8)((g<=0.) ? 0 : (g >= 1.) ? 255 : (int)(256.*sqrt(g)));
726 rgb[2] = (uint8)((b<=0.) ? 0 : (b >= 1.) ? 255 : (int)(256.*sqrt(b)));
733 LogL10toY(int p10) /* compute luminance from 10-bit LogL */
737 return (exp(M_LN2/64.*(p10+.5) - M_LN2*12.));
744 LogL10fromY(double Y, int em) /* get 10-bit LogL from Y */
748 else if (Y <= .00024283)
751 return itrunc(64.*(log2(Y) + 12.), em);
755 #define uv2ang(u, v) ( (NANGLES*.499999999/M_PI) \
756 * atan2((v)-V_NEU,(u)-U_NEU) + .5*NANGLES )
759 oog_encode(double u, double v) /* encode out-of-gamut chroma */
761 static int oog_table[NANGLES];
762 static int initialized = 0;
765 if (!initialized) { /* set up perimeter table */
766 double eps[NANGLES], ua, va, ang, epsa;
768 for (i = NANGLES; i--; )
770 for (vi = UV_NVS; vi--; ) {
771 va = UV_VSTART + (vi+.5)*UV_SQSIZ;
772 ustep = uv_row[vi].nus-1;
773 if (vi == UV_NVS-1 || vi == 0 || ustep <= 0)
775 for (ui = uv_row[vi].nus-1; ui >= 0; ui -= ustep) {
776 ua = uv_row[vi].ustart + (ui+.5)*UV_SQSIZ;
777 ang = uv2ang(ua, va);
779 epsa = fabs(ang - (i+.5));
781 oog_table[i] = uv_row[vi].ncum + ui;
786 for (i = NANGLES; i--; ) /* fill any holes */
789 for (i1 = 1; i1 < NANGLES/2; i1++)
790 if (eps[(i+i1)%NANGLES] < 1.5)
792 for (i2 = 1; i2 < NANGLES/2; i2++)
793 if (eps[(i+NANGLES-i2)%NANGLES] < 1.5)
797 oog_table[(i+i1)%NANGLES];
800 oog_table[(i+NANGLES-i2)%NANGLES];
804 i = (int) uv2ang(u, v); /* look up hue angle */
805 return (oog_table[i]);
815 uv_encode(double u, double v, int em) /* encode (u',v') coordinates */
820 return oog_encode(u, v);
821 vi = itrunc((v - UV_VSTART)*(1./UV_SQSIZ), em);
823 return oog_encode(u, v);
824 if (u < uv_row[vi].ustart)
825 return oog_encode(u, v);
826 ui = itrunc((u - uv_row[vi].ustart)*(1./UV_SQSIZ), em);
827 if (ui >= uv_row[vi].nus)
828 return oog_encode(u, v);
830 return (uv_row[vi].ncum + ui);
837 uv_decode(double *up, double *vp, int c) /* decode (u',v') index */
842 if (c < 0 || c >= UV_NDIVS)
844 lower = 0; /* binary search */
846 while (upper - lower > 1) {
847 vi = (lower + upper) >> 1;
848 ui = c - uv_row[vi].ncum;
859 ui = c - uv_row[vi].ncum;
860 *up = uv_row[vi].ustart + (ui+.5)*UV_SQSIZ;
861 *vp = UV_VSTART + (vi+.5)*UV_SQSIZ;
869 LogLuv24toXYZ(uint32 p, float XYZ[3])
872 double L, u, v, s, x, y;
873 /* decode luminance */
874 L = LogL10toY(p>>14 & 0x3ff);
876 XYZ[0] = XYZ[1] = XYZ[2] = 0.;
881 if (uv_decode(&u, &v, Ce) < 0) {
882 u = U_NEU; v = V_NEU;
884 s = 1./(6.*u - 16.*v + 12.);
888 XYZ[0] = (float)(x/y * L);
890 XYZ[2] = (float)((1.-x-y)/y * L);
897 LogLuv24fromXYZ(float XYZ[3], int em)
901 /* encode luminance */
902 Le = LogL10fromY(XYZ[1], em);
904 s = XYZ[0] + 15.*XYZ[1] + 3.*XYZ[2];
905 if (!Le || s <= 0.) {
912 Ce = uv_encode(u, v, em);
913 if (Ce < 0) /* never happens */
914 Ce = uv_encode(U_NEU, V_NEU, SGILOGENCODE_NODITHER);
915 /* combine encodings */
916 return (Le << 14 | Ce);
920 Luv24toXYZ(LogLuvState* sp, tidata_t op, int n)
922 uint32* luv = (uint32*) sp->tbuf;
923 float* xyz = (float*) op;
926 LogLuv24toXYZ(*luv, xyz);
933 Luv24toLuv48(LogLuvState* sp, tidata_t op, int n)
935 uint32* luv = (uint32*) sp->tbuf;
936 int16* luv3 = (int16*) op;
941 *luv3++ = (int16)((*luv >> 12 & 0xffd) + 13314);
942 if (uv_decode(&u, &v, *luv&0x3fff) < 0) {
946 *luv3++ = (int16)(u * (1L<<15));
947 *luv3++ = (int16)(v * (1L<<15));
953 Luv24toRGB(LogLuvState* sp, tidata_t op, int n)
955 uint32* luv = (uint32*) sp->tbuf;
956 uint8* rgb = (uint8*) op;
961 LogLuv24toXYZ(*luv++, xyz);
962 XYZtoRGB24(xyz, rgb);
968 Luv24fromXYZ(LogLuvState* sp, tidata_t op, int n)
970 uint32* luv = (uint32*) sp->tbuf;
971 float* xyz = (float*) op;
974 *luv++ = LogLuv24fromXYZ(xyz, sp->encode_meth);
980 Luv24fromLuv48(LogLuvState* sp, tidata_t op, int n)
982 uint32* luv = (uint32*) sp->tbuf;
983 int16* luv3 = (int16*) op;
990 else if (luv3[0] >= (1<<12)+3314)
992 else if (sp->encode_meth == SGILOGENCODE_NODITHER)
993 Le = (luv3[0]-3314) >> 2;
995 Le = itrunc(.25*(luv3[0]-3314.), sp->encode_meth);
997 Ce = uv_encode((luv3[1]+.5)/(1<<15), (luv3[2]+.5)/(1<<15),
999 if (Ce < 0) /* never happens */
1000 Ce = uv_encode(U_NEU, V_NEU, SGILOGENCODE_NODITHER);
1001 *luv++ = (uint32)Le << 14 | Ce;
1010 LogLuv32toXYZ(uint32 p, float XYZ[3])
1012 double L, u, v, s, x, y;
1013 /* decode luminance */
1014 L = LogL16toY((int)p >> 16);
1016 XYZ[0] = XYZ[1] = XYZ[2] = 0.;
1020 u = 1./UVSCALE * ((p>>8 & 0xff) + .5);
1021 v = 1./UVSCALE * ((p & 0xff) + .5);
1022 s = 1./(6.*u - 16.*v + 12.);
1025 /* convert to XYZ */
1026 XYZ[0] = (float)(x/y * L);
1028 XYZ[2] = (float)((1.-x-y)/y * L);
1035 LogLuv32fromXYZ(float XYZ[3], int em)
1037 unsigned int Le, ue, ve;
1039 /* encode luminance */
1040 Le = (unsigned int)LogL16fromY(XYZ[1], em);
1042 s = XYZ[0] + 15.*XYZ[1] + 3.*XYZ[2];
1043 if (!Le || s <= 0.) {
1050 if (u <= 0.) ue = 0;
1051 else ue = itrunc(UVSCALE*u, em);
1052 if (ue > 255) ue = 255;
1053 if (v <= 0.) ve = 0;
1054 else ve = itrunc(UVSCALE*v, em);
1055 if (ve > 255) ve = 255;
1056 /* combine encodings */
1057 return (Le << 16 | ue << 8 | ve);
1061 Luv32toXYZ(LogLuvState* sp, tidata_t op, int n)
1063 uint32* luv = (uint32*) sp->tbuf;
1064 float* xyz = (float*) op;
1067 LogLuv32toXYZ(*luv++, xyz);
1073 Luv32toLuv48(LogLuvState* sp, tidata_t op, int n)
1075 uint32* luv = (uint32*) sp->tbuf;
1076 int16* luv3 = (int16*) op;
1081 *luv3++ = (int16)(*luv >> 16);
1082 u = 1./UVSCALE * ((*luv>>8 & 0xff) + .5);
1083 v = 1./UVSCALE * ((*luv & 0xff) + .5);
1084 *luv3++ = (int16)(u * (1L<<15));
1085 *luv3++ = (int16)(v * (1L<<15));
1091 Luv32toRGB(LogLuvState* sp, tidata_t op, int n)
1093 uint32* luv = (uint32*) sp->tbuf;
1094 uint8* rgb = (uint8*) op;
1099 LogLuv32toXYZ(*luv++, xyz);
1100 XYZtoRGB24(xyz, rgb);
1106 Luv32fromXYZ(LogLuvState* sp, tidata_t op, int n)
1108 uint32* luv = (uint32*) sp->tbuf;
1109 float* xyz = (float*) op;
1112 *luv++ = LogLuv32fromXYZ(xyz, sp->encode_meth);
1118 Luv32fromLuv48(LogLuvState* sp, tidata_t op, int n)
1120 uint32* luv = (uint32*) sp->tbuf;
1121 int16* luv3 = (int16*) op;
1123 if (sp->encode_meth == SGILOGENCODE_NODITHER) {
1125 *luv++ = (uint32)luv3[0] << 16 |
1126 (luv3[1]*(uint32)(UVSCALE+.5) >> 7 & 0xff00) |
1127 (luv3[2]*(uint32)(UVSCALE+.5) >> 15 & 0xff);
1133 *luv++ = (uint32)luv3[0] << 16 |
1134 (itrunc(luv3[1]*(UVSCALE/(1<<15)), sp->encode_meth) << 8 & 0xff00) |
1135 (itrunc(luv3[2]*(UVSCALE/(1<<15)), sp->encode_meth) & 0xff);
1141 _logLuvNop(LogLuvState* sp, tidata_t op, int n)
1143 (void) sp; (void) op; (void) n;
1147 LogL16GuessDataFmt(TIFFDirectory *td)
1149 #define PACK(s,b,f) (((b)<<6)|((s)<<3)|(f))
1150 switch (PACK(td->td_samplesperpixel, td->td_bitspersample, td->td_sampleformat)) {
1151 case PACK(1, 32, SAMPLEFORMAT_IEEEFP):
1152 return (SGILOGDATAFMT_FLOAT);
1153 case PACK(1, 16, SAMPLEFORMAT_VOID):
1154 case PACK(1, 16, SAMPLEFORMAT_INT):
1155 case PACK(1, 16, SAMPLEFORMAT_UINT):
1156 return (SGILOGDATAFMT_16BIT);
1157 case PACK(1, 8, SAMPLEFORMAT_VOID):
1158 case PACK(1, 8, SAMPLEFORMAT_UINT):
1159 return (SGILOGDATAFMT_8BIT);
1162 return (SGILOGDATAFMT_UNKNOWN);
1166 multiply(size_t m1, size_t m2)
1168 uint32 bytes = m1 * m2;
1170 if (m1 && bytes / m1 != m2)
1177 LogL16InitState(TIFF* tif)
1179 TIFFDirectory *td = &tif->tif_dir;
1180 LogLuvState* sp = DecoderState(tif);
1181 static const char module[] = "LogL16InitState";
1184 assert(td->td_photometric == PHOTOMETRIC_LOGL);
1186 /* for some reason, we can't do this in TIFFInitLogL16 */
1187 if (sp->user_datafmt == SGILOGDATAFMT_UNKNOWN)
1188 sp->user_datafmt = LogL16GuessDataFmt(td);
1189 switch (sp->user_datafmt) {
1190 case SGILOGDATAFMT_FLOAT:
1191 sp->pixel_size = sizeof (float);
1193 case SGILOGDATAFMT_16BIT:
1194 sp->pixel_size = sizeof (int16);
1196 case SGILOGDATAFMT_8BIT:
1197 sp->pixel_size = sizeof (uint8);
1200 TIFFError(tif->tif_name,
1201 "No support for converting user data format to LogL");
1204 sp->tbuflen = multiply(td->td_imagewidth, td->td_rowsperstrip);
1205 if (multiply(sp->tbuflen, sizeof (int16)) == 0 ||
1206 (sp->tbuf = (tidata_t*) _TIFFmalloc(sp->tbuflen * sizeof (int16))) == NULL) {
1207 TIFFError(module, "%s: No space for SGILog translation buffer",
1215 LogLuvGuessDataFmt(TIFFDirectory *td)
1220 * If the user didn't tell us their datafmt,
1221 * take our best guess from the bitspersample.
1223 #define PACK(a,b) (((a)<<3)|(b))
1224 switch (PACK(td->td_bitspersample, td->td_sampleformat)) {
1225 case PACK(32, SAMPLEFORMAT_IEEEFP):
1226 guess = SGILOGDATAFMT_FLOAT;
1228 case PACK(32, SAMPLEFORMAT_VOID):
1229 case PACK(32, SAMPLEFORMAT_UINT):
1230 case PACK(32, SAMPLEFORMAT_INT):
1231 guess = SGILOGDATAFMT_RAW;
1233 case PACK(16, SAMPLEFORMAT_VOID):
1234 case PACK(16, SAMPLEFORMAT_INT):
1235 case PACK(16, SAMPLEFORMAT_UINT):
1236 guess = SGILOGDATAFMT_16BIT;
1238 case PACK( 8, SAMPLEFORMAT_VOID):
1239 case PACK( 8, SAMPLEFORMAT_UINT):
1240 guess = SGILOGDATAFMT_8BIT;
1243 guess = SGILOGDATAFMT_UNKNOWN;
1248 * Double-check samples per pixel.
1250 switch (td->td_samplesperpixel) {
1252 if (guess != SGILOGDATAFMT_RAW)
1253 guess = SGILOGDATAFMT_UNKNOWN;
1256 if (guess == SGILOGDATAFMT_RAW)
1257 guess = SGILOGDATAFMT_UNKNOWN;
1260 guess = SGILOGDATAFMT_UNKNOWN;
1267 LogLuvInitState(TIFF* tif)
1269 TIFFDirectory* td = &tif->tif_dir;
1270 LogLuvState* sp = DecoderState(tif);
1271 static const char module[] = "LogLuvInitState";
1274 assert(td->td_photometric == PHOTOMETRIC_LOGLUV);
1276 /* for some reason, we can't do this in TIFFInitLogLuv */
1277 if (td->td_planarconfig != PLANARCONFIG_CONTIG) {
1279 "SGILog compression cannot handle non-contiguous data");
1282 if (sp->user_datafmt == SGILOGDATAFMT_UNKNOWN)
1283 sp->user_datafmt = LogLuvGuessDataFmt(td);
1284 switch (sp->user_datafmt) {
1285 case SGILOGDATAFMT_FLOAT:
1286 sp->pixel_size = 3*sizeof (float);
1288 case SGILOGDATAFMT_16BIT:
1289 sp->pixel_size = 3*sizeof (int16);
1291 case SGILOGDATAFMT_RAW:
1292 sp->pixel_size = sizeof (uint32);
1294 case SGILOGDATAFMT_8BIT:
1295 sp->pixel_size = 3*sizeof (uint8);
1298 TIFFError(tif->tif_name,
1299 "No support for converting user data format to LogLuv");
1302 sp->tbuflen = multiply(td->td_imagewidth, td->td_rowsperstrip);
1303 if (multiply(sp->tbuflen, sizeof (uint32)) == 0 ||
1304 (sp->tbuf = (tidata_t*) _TIFFmalloc(sp->tbuflen * sizeof (uint32))) == NULL) {
1305 TIFFError(module, "%s: No space for SGILog translation buffer",
1313 LogLuvSetupDecode(TIFF* tif)
1315 LogLuvState* sp = DecoderState(tif);
1316 TIFFDirectory* td = &tif->tif_dir;
1318 tif->tif_postdecode = _TIFFNoPostDecode;
1319 switch (td->td_photometric) {
1320 case PHOTOMETRIC_LOGLUV:
1321 if (!LogLuvInitState(tif))
1323 if (td->td_compression == COMPRESSION_SGILOG24) {
1324 tif->tif_decoderow = LogLuvDecode24;
1325 switch (sp->user_datafmt) {
1326 case SGILOGDATAFMT_FLOAT:
1327 sp->tfunc = Luv24toXYZ;
1329 case SGILOGDATAFMT_16BIT:
1330 sp->tfunc = Luv24toLuv48;
1332 case SGILOGDATAFMT_8BIT:
1333 sp->tfunc = Luv24toRGB;
1337 tif->tif_decoderow = LogLuvDecode32;
1338 switch (sp->user_datafmt) {
1339 case SGILOGDATAFMT_FLOAT:
1340 sp->tfunc = Luv32toXYZ;
1342 case SGILOGDATAFMT_16BIT:
1343 sp->tfunc = Luv32toLuv48;
1345 case SGILOGDATAFMT_8BIT:
1346 sp->tfunc = Luv32toRGB;
1351 case PHOTOMETRIC_LOGL:
1352 if (!LogL16InitState(tif))
1354 tif->tif_decoderow = LogL16Decode;
1355 switch (sp->user_datafmt) {
1356 case SGILOGDATAFMT_FLOAT:
1359 case SGILOGDATAFMT_8BIT:
1360 sp->tfunc = L16toGry;
1365 TIFFError(tif->tif_name,
1366 "Inappropriate photometric interpretation %d for SGILog compression; %s",
1367 td->td_photometric, "must be either LogLUV or LogL");
1374 LogLuvSetupEncode(TIFF* tif)
1376 LogLuvState* sp = EncoderState(tif);
1377 TIFFDirectory* td = &tif->tif_dir;
1379 switch (td->td_photometric) {
1380 case PHOTOMETRIC_LOGLUV:
1381 if (!LogLuvInitState(tif))
1383 if (td->td_compression == COMPRESSION_SGILOG24) {
1384 tif->tif_encoderow = LogLuvEncode24;
1385 switch (sp->user_datafmt) {
1386 case SGILOGDATAFMT_FLOAT:
1387 sp->tfunc = Luv24fromXYZ;
1389 case SGILOGDATAFMT_16BIT:
1390 sp->tfunc = Luv24fromLuv48;
1392 case SGILOGDATAFMT_RAW:
1398 tif->tif_encoderow = LogLuvEncode32;
1399 switch (sp->user_datafmt) {
1400 case SGILOGDATAFMT_FLOAT:
1401 sp->tfunc = Luv32fromXYZ;
1403 case SGILOGDATAFMT_16BIT:
1404 sp->tfunc = Luv32fromLuv48;
1406 case SGILOGDATAFMT_RAW:
1413 case PHOTOMETRIC_LOGL:
1414 if (!LogL16InitState(tif))
1416 tif->tif_encoderow = LogL16Encode;
1417 switch (sp->user_datafmt) {
1418 case SGILOGDATAFMT_FLOAT:
1419 sp->tfunc = L16fromY;
1421 case SGILOGDATAFMT_16BIT:
1428 TIFFError(tif->tif_name,
1429 "Inappropriate photometric interpretation %d for SGILog compression; %s",
1430 td->td_photometric, "must be either LogLUV or LogL");
1435 TIFFError(tif->tif_name,
1436 "SGILog compression supported only for %s, or raw data",
1437 td->td_photometric == PHOTOMETRIC_LOGL ? "Y, L" : "XYZ, Luv");
1442 LogLuvClose(TIFF* tif)
1444 TIFFDirectory *td = &tif->tif_dir;
1447 * For consistency, we always want to write out the same
1448 * bitspersample and sampleformat for our TIFF file,
1449 * regardless of the data format being used by the application.
1450 * Since this routine is called after tags have been set but
1451 * before they have been recorded in the file, we reset them here.
1453 td->td_samplesperpixel =
1454 (td->td_photometric == PHOTOMETRIC_LOGL) ? 1 : 3;
1455 td->td_bitspersample = 16;
1456 td->td_sampleformat = SAMPLEFORMAT_INT;
1460 LogLuvCleanup(TIFF* tif)
1462 LogLuvState* sp = (LogLuvState *)tif->tif_data;
1466 _TIFFfree(sp->tbuf);
1468 tif->tif_data = NULL;
1473 LogLuvVSetField(TIFF* tif, ttag_t tag, va_list ap)
1475 LogLuvState* sp = DecoderState(tif);
1479 case TIFFTAG_SGILOGDATAFMT:
1480 sp->user_datafmt = va_arg(ap, int);
1482 * Tweak the TIFF header so that the rest of libtiff knows what
1483 * size of data will be passed between app and library, and
1484 * assume that the app knows what it is doing and is not
1485 * confused by these header manipulations...
1487 switch (sp->user_datafmt) {
1488 case SGILOGDATAFMT_FLOAT:
1489 bps = 32, fmt = SAMPLEFORMAT_IEEEFP;
1491 case SGILOGDATAFMT_16BIT:
1492 bps = 16, fmt = SAMPLEFORMAT_INT;
1494 case SGILOGDATAFMT_RAW:
1495 bps = 32, fmt = SAMPLEFORMAT_UINT;
1496 TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, 1);
1498 case SGILOGDATAFMT_8BIT:
1499 bps = 8, fmt = SAMPLEFORMAT_UINT;
1502 TIFFError(tif->tif_name,
1503 "Unknown data format %d for LogLuv compression",
1507 TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, bps);
1508 TIFFSetField(tif, TIFFTAG_SAMPLEFORMAT, fmt);
1510 * Must recalculate sizes should bits/sample change.
1512 tif->tif_tilesize = isTiled(tif) ? TIFFTileSize(tif) : (tsize_t) -1;
1513 tif->tif_scanlinesize = TIFFScanlineSize(tif);
1515 case TIFFTAG_SGILOGENCODE:
1516 sp->encode_meth = va_arg(ap, int);
1517 if (sp->encode_meth != SGILOGENCODE_NODITHER &&
1518 sp->encode_meth != SGILOGENCODE_RANDITHER) {
1519 TIFFError(tif->tif_name,
1520 "Unknown encoding %d for LogLuv compression",
1526 return (*sp->vsetparent)(tif, tag, ap);
1531 LogLuvVGetField(TIFF* tif, ttag_t tag, va_list ap)
1533 LogLuvState *sp = (LogLuvState *)tif->tif_data;
1536 case TIFFTAG_SGILOGDATAFMT:
1537 *va_arg(ap, int*) = sp->user_datafmt;
1540 return (*sp->vgetparent)(tif, tag, ap);
1544 static const TIFFFieldInfo LogLuvFieldInfo[] = {
1545 { TIFFTAG_SGILOGDATAFMT, 0, 0, TIFF_SHORT, FIELD_PSEUDO,
1546 TRUE, FALSE, "SGILogDataFmt"},
1547 { TIFFTAG_SGILOGENCODE, 0, 0, TIFF_SHORT, FIELD_PSEUDO,
1548 TRUE, FALSE, "SGILogEncode"}
1552 TIFFInitSGILog(TIFF* tif, int scheme)
1554 static const char module[] = "TIFFInitSGILog";
1557 assert(scheme == COMPRESSION_SGILOG24 || scheme == COMPRESSION_SGILOG);
1560 * Allocate state block so tag methods have storage to record values.
1562 tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (LogLuvState));
1563 if (tif->tif_data == NULL)
1565 sp = (LogLuvState*) tif->tif_data;
1566 _TIFFmemset((tdata_t)sp, 0, sizeof (*sp));
1567 sp->user_datafmt = SGILOGDATAFMT_UNKNOWN;
1568 sp->encode_meth = (scheme == COMPRESSION_SGILOG24) ?
1569 SGILOGENCODE_RANDITHER : SGILOGENCODE_NODITHER;
1570 sp->tfunc = _logLuvNop;
1573 * Install codec methods.
1574 * NB: tif_decoderow & tif_encoderow are filled
1577 tif->tif_setupdecode = LogLuvSetupDecode;
1578 tif->tif_decodestrip = LogLuvDecodeStrip;
1579 tif->tif_decodetile = LogLuvDecodeTile;
1580 tif->tif_setupencode = LogLuvSetupEncode;
1581 tif->tif_encodestrip = LogLuvEncodeStrip;
1582 tif->tif_encodetile = LogLuvEncodeTile;
1583 tif->tif_close = LogLuvClose;
1584 tif->tif_cleanup = LogLuvCleanup;
1586 /* override SetField so we can handle our private pseudo-tag */
1587 _TIFFMergeFieldInfo(tif, LogLuvFieldInfo, N(LogLuvFieldInfo));
1588 sp->vgetparent = tif->tif_tagmethods.vgetfield;
1589 tif->tif_tagmethods.vgetfield = LogLuvVGetField; /* hook for codec tags */
1590 sp->vsetparent = tif->tif_tagmethods.vsetfield;
1591 tif->tif_tagmethods.vsetfield = LogLuvVSetField; /* hook for codec tags */
1595 TIFFError(module, "%s: No space for LogLuv state block", tif->tif_name);
1598 #endif /* LOGLUV_SUPPORT */
1600 /* vim: set ts=8 sts=8 sw=8 noet: */