/* $Id: tif_luv.c,v 1.4 2010/01/26 15:56:36 scuri Exp $ */ /* * Copyright (c) 1997 Greg Ward Larson * Copyright (c) 1997 Silicon Graphics, Inc. * * Permission to use, copy, modify, distribute, and sell this software and * its documentation for any purpose is hereby granted without fee, provided * that (i) the above copyright notices and this permission notice appear in * all copies of the software and related documentation, and (ii) the names of * Sam Leffler, Greg Larson and Silicon Graphics may not be used in any * advertising or publicity relating to the software without the specific, * prior written permission of Sam Leffler, Greg Larson and Silicon Graphics. * * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. * * IN NO EVENT SHALL SAM LEFFLER, GREG LARSON OR SILICON GRAPHICS BE LIABLE * FOR ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE * OF THIS SOFTWARE. */ #include "tiffiop.h" #ifdef LOGLUV_SUPPORT /* * TIFF Library. * LogLuv compression support for high dynamic range images. * * Contributed by Greg Larson. * * LogLuv image support uses the TIFF library to store 16 or 10-bit * log luminance values with 8 bits each of u and v or a 14-bit index. * * The codec can take as input and produce as output 32-bit IEEE float values * as well as 16-bit integer values. A 16-bit luminance is interpreted * as a sign bit followed by a 15-bit integer that is converted * to and from a linear magnitude using the transformation: * * L = 2^( (Le+.5)/256 - 64 ) # real from 15-bit * * Le = floor( 256*(log2(L) + 64) ) # 15-bit from real * * The actual conversion to world luminance units in candelas per sq. meter * requires an additional multiplier, which is stored in the TIFFTAG_STONITS. * This value is usually set such that a reasonable exposure comes from * clamping decoded luminances above 1 to 1 in the displayed image. * * The 16-bit values for u and v may be converted to real values by dividing * each by 32768. (This allows for negative values, which aren't useful as * far as we know, but are left in case of future improvements in human * color vision.) * * Conversion from (u,v), which is actually the CIE (u',v') system for * you color scientists, is accomplished by the following transformation: * * u = 4*x / (-2*x + 12*y + 3) * v = 9*y / (-2*x + 12*y + 3) * * x = 9*u / (6*u - 16*v + 12) * y = 4*v / (6*u - 16*v + 12) * * This process is greatly simplified by passing 32-bit IEEE floats * for each of three CIE XYZ coordinates. The codec then takes care * of conversion to and from LogLuv, though the application is still * responsible for interpreting the TIFFTAG_STONITS calibration factor. * * By definition, a CIE XYZ vector of [1 1 1] corresponds to a neutral white * point of (x,y)=(1/3,1/3). However, most color systems assume some other * white point, such as D65, and an absolute color conversion to XYZ then * to another color space with a different white point may introduce an * unwanted color cast to the image. It is often desirable, therefore, to * perform a white point conversion that maps the input white to [1 1 1] * in XYZ, then record the original white point using the TIFFTAG_WHITEPOINT * tag value. A decoder that demands absolute color calibration may use * this white point tag to get back the original colors, but usually it * will be ignored and the new white point will be used instead that * matches the output color space. * * Pixel information is compressed into one of two basic encodings, depending * on the setting of the compression tag, which is one of COMPRESSION_SGILOG * or COMPRESSION_SGILOG24. For COMPRESSION_SGILOG, greyscale data is * stored as: * * 1 15 * |-+---------------| * * COMPRESSION_SGILOG color data is stored as: * * 1 15 8 8 * |-+---------------|--------+--------| * S Le ue ve * * For the 24-bit COMPRESSION_SGILOG24 color format, the data is stored as: * * 10 14 * |----------|--------------| * Le' Ce * * There is no sign bit in the 24-bit case, and the (u,v) chromaticity is * encoded as an index for optimal color resolution. The 10 log bits are * defined by the following conversions: * * L = 2^((Le'+.5)/64 - 12) # real from 10-bit * * Le' = floor( 64*(log2(L) + 12) ) # 10-bit from real * * The 10 bits of the smaller format may be converted into the 15 bits of * the larger format by multiplying by 4 and adding 13314. Obviously, * a smaller range of magnitudes is covered (about 5 orders of magnitude * instead of 38), and the lack of a sign bit means that negative luminances * are not allowed. (Well, they aren't allowed in the real world, either, * but they are useful for certain types of image processing.) * * The desired user format is controlled by the setting the internal * pseudo tag TIFFTAG_SGILOGDATAFMT to one of: * SGILOGDATAFMT_FLOAT = IEEE 32-bit float XYZ values * SGILOGDATAFMT_16BIT = 16-bit integer encodings of logL, u and v * Raw data i/o is also possible using: * SGILOGDATAFMT_RAW = 32-bit unsigned integer with encoded pixel * In addition, the following decoding is provided for ease of display: * SGILOGDATAFMT_8BIT = 8-bit default RGB gamma-corrected values * * For grayscale images, we provide the following data formats: * SGILOGDATAFMT_FLOAT = IEEE 32-bit float Y values * SGILOGDATAFMT_16BIT = 16-bit integer w/ encoded luminance * SGILOGDATAFMT_8BIT = 8-bit gray monitor values * * Note that the COMPRESSION_SGILOG applies a simple run-length encoding * scheme by separating the logL, u and v bytes for each row and applying * a PackBits type of compression. Since the 24-bit encoding is not * adaptive, the 32-bit color format takes less space in many cases. * * Further control is provided over the conversion from higher-resolution * formats to final encoded values through the pseudo tag * TIFFTAG_SGILOGENCODE: * SGILOGENCODE_NODITHER = do not dither encoded values * SGILOGENCODE_RANDITHER = apply random dithering during encoding * * The default value of this tag is SGILOGENCODE_NODITHER for * COMPRESSION_SGILOG to maximize run-length encoding and * SGILOGENCODE_RANDITHER for COMPRESSION_SGILOG24 to turn * quantization errors into noise. */ #include #include #include /* * State block for each open TIFF * file using LogLuv compression/decompression. */ typedef struct logLuvState LogLuvState; struct logLuvState { int user_datafmt; /* user data format */ int encode_meth; /* encoding method */ int pixel_size; /* bytes per pixel */ tidata_t* tbuf; /* translation buffer */ int tbuflen; /* buffer length */ void (*tfunc)(LogLuvState*, tidata_t, int); TIFFVSetMethod vgetparent; /* super-class method */ TIFFVSetMethod vsetparent; /* super-class method */ }; #define DecoderState(tif) ((LogLuvState*) (tif)->tif_data) #define EncoderState(tif) ((LogLuvState*) (tif)->tif_data) #define SGILOGDATAFMT_UNKNOWN -1 #define MINRUN 4 /* minimum run length */ /* * Decode a string of 16-bit gray pixels. */ static int LogL16Decode(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s) { LogLuvState* sp = DecoderState(tif); int shft, i, npixels; unsigned char* bp; int16* tp; int16 b; int cc, rc; assert(s == 0); assert(sp != NULL); npixels = occ / sp->pixel_size; if (sp->user_datafmt == SGILOGDATAFMT_16BIT) tp = (int16*) op; else { assert(sp->tbuflen >= npixels); tp = (int16*) sp->tbuf; } _TIFFmemset((tdata_t) tp, 0, npixels*sizeof (tp[0])); bp = (unsigned char*) tif->tif_rawcp; cc = tif->tif_rawcc; /* get each byte string */ for (shft = 2*8; (shft -= 8) >= 0; ) { for (i = 0; i < npixels && cc > 0; ) if (*bp >= 128) { /* run */ rc = *bp++ + (2-128); b = (int16)(*bp++ << shft); cc -= 2; while (rc-- && i < npixels) tp[i++] |= b; } else { /* non-run */ rc = *bp++; /* nul is noop */ while (--cc && rc-- && i < npixels) tp[i++] |= (int16)*bp++ << shft; } if (i != npixels) { TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "LogL16Decode: Not enough data at row %d (short %d pixels)", tif->tif_row, npixels - i); tif->tif_rawcp = (tidata_t) bp; tif->tif_rawcc = cc; return (0); } } (*sp->tfunc)(sp, op, npixels); tif->tif_rawcp = (tidata_t) bp; tif->tif_rawcc = cc; return (1); } /* * Decode a string of 24-bit pixels. */ static int LogLuvDecode24(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s) { LogLuvState* sp = DecoderState(tif); int cc, i, npixels; unsigned char* bp; uint32* tp; assert(s == 0); assert(sp != NULL); npixels = occ / sp->pixel_size; if (sp->user_datafmt == SGILOGDATAFMT_RAW) tp = (uint32 *)op; else { assert(sp->tbuflen >= npixels); tp = (uint32 *) sp->tbuf; } /* copy to array of uint32 */ bp = (unsigned char*) tif->tif_rawcp; cc = tif->tif_rawcc; for (i = 0; i < npixels && cc > 0; i++) { tp[i] = bp[0] << 16 | bp[1] << 8 | bp[2]; bp += 3; cc -= 3; } tif->tif_rawcp = (tidata_t) bp; tif->tif_rawcc = cc; if (i != npixels) { TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "LogLuvDecode24: Not enough data at row %d (short %d pixels)", tif->tif_row, npixels - i); return (0); } (*sp->tfunc)(sp, op, npixels); return (1); } /* * Decode a string of 32-bit pixels. */ static int LogLuvDecode32(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s) { LogLuvState* sp; int shft, i, npixels; unsigned char* bp; uint32* tp; uint32 b; int cc, rc; assert(s == 0); sp = DecoderState(tif); assert(sp != NULL); npixels = occ / sp->pixel_size; if (sp->user_datafmt == SGILOGDATAFMT_RAW) tp = (uint32*) op; else { assert(sp->tbuflen >= npixels); tp = (uint32*) sp->tbuf; } _TIFFmemset((tdata_t) tp, 0, npixels*sizeof (tp[0])); bp = (unsigned char*) tif->tif_rawcp; cc = tif->tif_rawcc; /* get each byte string */ for (shft = 4*8; (shft -= 8) >= 0; ) { for (i = 0; i < npixels && cc > 0; ) if (*bp >= 128) { /* run */ rc = *bp++ + (2-128); b = (uint32)*bp++ << shft; cc -= 2; while (rc-- && i < npixels) tp[i++] |= b; } else { /* non-run */ rc = *bp++; /* nul is noop */ while (--cc && rc-- && i < npixels) tp[i++] |= (uint32)*bp++ << shft; } if (i != npixels) { TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "LogLuvDecode32: Not enough data at row %d (short %d pixels)", tif->tif_row, npixels - i); tif->tif_rawcp = (tidata_t) bp; tif->tif_rawcc = cc; return (0); } } (*sp->tfunc)(sp, op, npixels); tif->tif_rawcp = (tidata_t) bp; tif->tif_rawcc = cc; return (1); } /* * Decode a strip of pixels. We break it into rows to * maintain synchrony with the encode algorithm, which * is row by row. */ static int LogLuvDecodeStrip(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s) { tsize_t rowlen = TIFFScanlineSize(tif); assert(cc%rowlen == 0); while (cc && (*tif->tif_decoderow)(tif, bp, rowlen, s)) bp += rowlen, cc -= rowlen; return (cc == 0); } /* * Decode a tile of pixels. We break it into rows to * maintain synchrony with the encode algorithm, which * is row by row. */ static int LogLuvDecodeTile(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s) { tsize_t rowlen = TIFFTileRowSize(tif); assert(cc%rowlen == 0); while (cc && (*tif->tif_decoderow)(tif, bp, rowlen, s)) bp += rowlen, cc -= rowlen; return (cc == 0); } /* * Encode a row of 16-bit pixels. */ static int LogL16Encode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s) { LogLuvState* sp = EncoderState(tif); int shft, i, j, npixels; tidata_t op; int16* tp; int16 b; int occ, rc=0, mask, beg; assert(s == 0); assert(sp != NULL); npixels = cc / sp->pixel_size; if (sp->user_datafmt == SGILOGDATAFMT_16BIT) tp = (int16*) bp; else { tp = (int16*) sp->tbuf; assert(sp->tbuflen >= npixels); (*sp->tfunc)(sp, bp, npixels); } /* compress each byte string */ op = tif->tif_rawcp; occ = tif->tif_rawdatasize - tif->tif_rawcc; for (shft = 2*8; (shft -= 8) >= 0; ) for (i = 0; i < npixels; i += rc) { if (occ < 4) { tif->tif_rawcp = op; tif->tif_rawcc = tif->tif_rawdatasize - occ; if (!TIFFFlushData1(tif)) return (-1); op = tif->tif_rawcp; occ = tif->tif_rawdatasize - tif->tif_rawcc; } mask = 0xff << shft; /* find next run */ for (beg = i; beg < npixels; beg += rc) { b = (int16) (tp[beg] & mask); rc = 1; while (rc < 127+2 && beg+rc < npixels && (tp[beg+rc] & mask) == b) rc++; if (rc >= MINRUN) break; /* long enough */ } if (beg-i > 1 && beg-i < MINRUN) { b = (int16) (tp[i] & mask);/*check short run */ j = i+1; while ((tp[j++] & mask) == b) if (j == beg) { *op++ = (tidataval_t)(128-2+j-i); *op++ = (tidataval_t) (b >> shft); occ -= 2; i = beg; break; } } while (i < beg) { /* write out non-run */ if ((j = beg-i) > 127) j = 127; if (occ < j+3) { tif->tif_rawcp = op; tif->tif_rawcc = tif->tif_rawdatasize - occ; if (!TIFFFlushData1(tif)) return (-1); op = tif->tif_rawcp; occ = tif->tif_rawdatasize - tif->tif_rawcc; } *op++ = (tidataval_t) j; occ--; while (j--) { *op++ = (tidataval_t) (tp[i++] >> shft & 0xff); occ--; } } if (rc >= MINRUN) { /* write out run */ *op++ = (tidataval_t) (128-2+rc); *op++ = (tidataval_t) (tp[beg] >> shft & 0xff); occ -= 2; } else rc = 0; } tif->tif_rawcp = op; tif->tif_rawcc = tif->tif_rawdatasize - occ; return (0); } /* * Encode a row of 24-bit pixels. */ static int LogLuvEncode24(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s) { LogLuvState* sp = EncoderState(tif); int i, npixels, occ; tidata_t op; uint32* tp; assert(s == 0); assert(sp != NULL); npixels = cc / sp->pixel_size; if (sp->user_datafmt == SGILOGDATAFMT_RAW) tp = (uint32*) bp; else { tp = (uint32*) sp->tbuf; assert(sp->tbuflen >= npixels); (*sp->tfunc)(sp, bp, npixels); } /* write out encoded pixels */ op = tif->tif_rawcp; occ = tif->tif_rawdatasize - tif->tif_rawcc; for (i = npixels; i--; ) { if (occ < 3) { tif->tif_rawcp = op; tif->tif_rawcc = tif->tif_rawdatasize - occ; if (!TIFFFlushData1(tif)) return (-1); op = tif->tif_rawcp; occ = tif->tif_rawdatasize - tif->tif_rawcc; } *op++ = (tidataval_t)(*tp >> 16); *op++ = (tidataval_t)(*tp >> 8 & 0xff); *op++ = (tidataval_t)(*tp++ & 0xff); occ -= 3; } tif->tif_rawcp = op; tif->tif_rawcc = tif->tif_rawdatasize - occ; return (0); } /* * Encode a row of 32-bit pixels. */ static int LogLuvEncode32(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s) { LogLuvState* sp = EncoderState(tif); int shft, i, j, npixels; tidata_t op; uint32* tp; uint32 b; int occ, rc=0, mask, beg; assert(s == 0); assert(sp != NULL); npixels = cc / sp->pixel_size; if (sp->user_datafmt == SGILOGDATAFMT_RAW) tp = (uint32*) bp; else { tp = (uint32*) sp->tbuf; assert(sp->tbuflen >= npixels); (*sp->tfunc)(sp, bp, npixels); } /* compress each byte string */ op = tif->tif_rawcp; occ = tif->tif_rawdatasize - tif->tif_rawcc; for (shft = 4*8; (shft -= 8) >= 0; ) for (i = 0; i < npixels; i += rc) { if (occ < 4) { tif->tif_rawcp = op; tif->tif_rawcc = tif->tif_rawdatasize - occ; if (!TIFFFlushData1(tif)) return (-1); op = tif->tif_rawcp; occ = tif->tif_rawdatasize - tif->tif_rawcc; } mask = 0xff << shft; /* find next run */ for (beg = i; beg < npixels; beg += rc) { b = tp[beg] & mask; rc = 1; while (rc < 127+2 && beg+rc < npixels && (tp[beg+rc] & mask) == b) rc++; if (rc >= MINRUN) break; /* long enough */ } if (beg-i > 1 && beg-i < MINRUN) { b = tp[i] & mask; /* check short run */ j = i+1; while ((tp[j++] & mask) == b) if (j == beg) { *op++ = (tidataval_t)(128-2+j-i); *op++ = (tidataval_t)(b >> shft); occ -= 2; i = beg; break; } } while (i < beg) { /* write out non-run */ if ((j = beg-i) > 127) j = 127; if (occ < j+3) { tif->tif_rawcp = op; tif->tif_rawcc = tif->tif_rawdatasize - occ; if (!TIFFFlushData1(tif)) return (-1); op = tif->tif_rawcp; occ = tif->tif_rawdatasize - tif->tif_rawcc; } *op++ = (tidataval_t) j; occ--; while (j--) { *op++ = (tidataval_t)(tp[i++] >> shft & 0xff); occ--; } } if (rc >= MINRUN) { /* write out run */ *op++ = (tidataval_t) (128-2+rc); *op++ = (tidataval_t)(tp[beg] >> shft & 0xff); occ -= 2; } else rc = 0; } tif->tif_rawcp = op; tif->tif_rawcc = tif->tif_rawdatasize - occ; return (0); } /* * Encode a strip of pixels. We break it into rows to * avoid encoding runs across row boundaries. */ static int LogLuvEncodeStrip(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s) { tsize_t rowlen = TIFFScanlineSize(tif); assert(cc%rowlen == 0); while (cc && (*tif->tif_encoderow)(tif, bp, rowlen, s) == 0) bp += rowlen, cc -= rowlen; return (cc == 0); } /* * Encode a tile of pixels. We break it into rows to * avoid encoding runs across row boundaries. */ static int LogLuvEncodeTile(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s) { tsize_t rowlen = TIFFTileRowSize(tif); assert(cc%rowlen == 0); while (cc && (*tif->tif_encoderow)(tif, bp, rowlen, s) == 0) bp += rowlen, cc -= rowlen; return (cc == 0); } /* * Encode/Decode functions for converting to and from user formats. */ #include "uvcode.h" #ifndef UVSCALE #define U_NEU 0.210526316 #define V_NEU 0.473684211 #define UVSCALE 410. #endif #ifndef M_LN2 #define M_LN2 0.69314718055994530942 #endif #ifndef M_PI #define M_PI 3.14159265358979323846 #endif #define log2(x) ((1./M_LN2)*log(x)) #define exp2(x) exp(M_LN2*(x)) #define itrunc(x,m) ((m)==SGILOGENCODE_NODITHER ? \ (int)(x) : \ (int)((x) + rand()*(1./RAND_MAX) - .5)) #if !LOGLUV_PUBLIC static #endif double LogL16toY(int p16) /* compute luminance from 16-bit LogL */ { int Le = p16 & 0x7fff; double Y; if (!Le) return (0.); Y = exp(M_LN2/256.*(Le+.5) - M_LN2*64.); return (!(p16 & 0x8000) ? Y : -Y); } #if !LOGLUV_PUBLIC static #endif int LogL16fromY(double Y, int em) /* get 16-bit LogL from Y */ { if (Y >= 1.8371976e19) return (0x7fff); if (Y <= -1.8371976e19) return (0xffff); if (Y > 5.4136769e-20) return itrunc(256.*(log2(Y) + 64.), em); if (Y < -5.4136769e-20) return (~0x7fff | itrunc(256.*(log2(-Y) + 64.), em)); return (0); } static void L16toY(LogLuvState* sp, tidata_t op, int n) { int16* l16 = (int16*) sp->tbuf; float* yp = (float*) op; while (n-- > 0) *yp++ = (float)LogL16toY(*l16++); } static void L16toGry(LogLuvState* sp, tidata_t op, int n) { int16* l16 = (int16*) sp->tbuf; uint8* gp = (uint8*) op; while (n-- > 0) { double Y = LogL16toY(*l16++); *gp++ = (uint8) ((Y <= 0.) ? 0 : (Y >= 1.) ? 255 : (int)(256.*sqrt(Y))); } } static void L16fromY(LogLuvState* sp, tidata_t op, int n) { int16* l16 = (int16*) sp->tbuf; float* yp = (float*) op; while (n-- > 0) *l16++ = (int16) (LogL16fromY(*yp++, sp->encode_meth)); } #if !LOGLUV_PUBLIC static #endif void XYZtoRGB24(float xyz[3], uint8 rgb[3]) { double r, g, b; /* assume CCIR-709 primaries */ r = 2.690*xyz[0] + -1.276*xyz[1] + -0.414*xyz[2]; g = -1.022*xyz[0] + 1.978*xyz[1] + 0.044*xyz[2]; b = 0.061*xyz[0] + -0.224*xyz[1] + 1.163*xyz[2]; /* assume 2.0 gamma for speed */ /* could use integer sqrt approx., but this is probably faster */ rgb[0] = (uint8)((r<=0.) ? 0 : (r >= 1.) ? 255 : (int)(256.*sqrt(r))); rgb[1] = (uint8)((g<=0.) ? 0 : (g >= 1.) ? 255 : (int)(256.*sqrt(g))); rgb[2] = (uint8)((b<=0.) ? 0 : (b >= 1.) ? 255 : (int)(256.*sqrt(b))); } #if !LOGLUV_PUBLIC static #endif double LogL10toY(int p10) /* compute luminance from 10-bit LogL */ { if (p10 == 0) return (0.); return (exp(M_LN2/64.*(p10+.5) - M_LN2*12.)); } #if !LOGLUV_PUBLIC static #endif int LogL10fromY(double Y, int em) /* get 10-bit LogL from Y */ { if (Y >= 15.742) return (0x3ff); else if (Y <= .00024283) return (0); else return itrunc(64.*(log2(Y) + 12.), em); } #define NANGLES 100 #define uv2ang(u, v) ( (NANGLES*.499999999/M_PI) \ * atan2((v)-V_NEU,(u)-U_NEU) + .5*NANGLES ) static int oog_encode(double u, double v) /* encode out-of-gamut chroma */ { static int oog_table[NANGLES]; static int initialized = 0; register int i; if (!initialized) { /* set up perimeter table */ double eps[NANGLES], ua, va, ang, epsa; int ui, vi, ustep; for (i = NANGLES; i--; ) eps[i] = 2.; for (vi = UV_NVS; vi--; ) { va = UV_VSTART + (vi+.5)*UV_SQSIZ; ustep = uv_row[vi].nus-1; if (vi == UV_NVS-1 || vi == 0 || ustep <= 0) ustep = 1; for (ui = uv_row[vi].nus-1; ui >= 0; ui -= ustep) { ua = uv_row[vi].ustart + (ui+.5)*UV_SQSIZ; ang = uv2ang(ua, va); i = (int) ang; epsa = fabs(ang - (i+.5)); if (epsa < eps[i]) { oog_table[i] = uv_row[vi].ncum + ui; eps[i] = epsa; } } } for (i = NANGLES; i--; ) /* fill any holes */ if (eps[i] > 1.5) { int i1, i2; for (i1 = 1; i1 < NANGLES/2; i1++) if (eps[(i+i1)%NANGLES] < 1.5) break; for (i2 = 1; i2 < NANGLES/2; i2++) if (eps[(i+NANGLES-i2)%NANGLES] < 1.5) break; if (i1 < i2) oog_table[i] = oog_table[(i+i1)%NANGLES]; else oog_table[i] = oog_table[(i+NANGLES-i2)%NANGLES]; } initialized = 1; } i = (int) uv2ang(u, v); /* look up hue angle */ return (oog_table[i]); } #undef uv2ang #undef NANGLES #if !LOGLUV_PUBLIC static #endif int uv_encode(double u, double v, int em) /* encode (u',v') coordinates */ { register int vi, ui; if (v < UV_VSTART) return oog_encode(u, v); vi = itrunc((v - UV_VSTART)*(1./UV_SQSIZ), em); if (vi >= UV_NVS) return oog_encode(u, v); if (u < uv_row[vi].ustart) return oog_encode(u, v); ui = itrunc((u - uv_row[vi].ustart)*(1./UV_SQSIZ), em); if (ui >= uv_row[vi].nus) return oog_encode(u, v); return (uv_row[vi].ncum + ui); } #if !LOGLUV_PUBLIC static #endif int uv_decode(double *up, double *vp, int c) /* decode (u',v') index */ { int upper, lower; register int ui, vi; if (c < 0 || c >= UV_NDIVS) return (-1); lower = 0; /* binary search */ upper = UV_NVS; while (upper - lower > 1) { vi = (lower + upper) >> 1; ui = c - uv_row[vi].ncum; if (ui > 0) lower = vi; else if (ui < 0) upper = vi; else { lower = vi; break; } } vi = lower; ui = c - uv_row[vi].ncum; *up = uv_row[vi].ustart + (ui+.5)*UV_SQSIZ; *vp = UV_VSTART + (vi+.5)*UV_SQSIZ; return (0); } #if !LOGLUV_PUBLIC static #endif void LogLuv24toXYZ(uint32 p, float XYZ[3]) { int Ce; double L, u, v, s, x, y; /* decode luminance */ L = LogL10toY(p>>14 & 0x3ff); if (L <= 0.) { XYZ[0] = XYZ[1] = XYZ[2] = 0.; return; } /* decode color */ Ce = p & 0x3fff; if (uv_decode(&u, &v, Ce) < 0) { u = U_NEU; v = V_NEU; } s = 1./(6.*u - 16.*v + 12.); x = 9.*u * s; y = 4.*v * s; /* convert to XYZ */ XYZ[0] = (float)(x/y * L); XYZ[1] = (float)L; XYZ[2] = (float)((1.-x-y)/y * L); } #if !LOGLUV_PUBLIC static #endif uint32 LogLuv24fromXYZ(float XYZ[3], int em) { int Le, Ce; double u, v, s; /* encode luminance */ Le = LogL10fromY(XYZ[1], em); /* encode color */ s = XYZ[0] + 15.*XYZ[1] + 3.*XYZ[2]; if (!Le || s <= 0.) { u = U_NEU; v = V_NEU; } else { u = 4.*XYZ[0] / s; v = 9.*XYZ[1] / s; } Ce = uv_encode(u, v, em); if (Ce < 0) /* never happens */ Ce = uv_encode(U_NEU, V_NEU, SGILOGENCODE_NODITHER); /* combine encodings */ return (Le << 14 | Ce); } static void Luv24toXYZ(LogLuvState* sp, tidata_t op, int n) { uint32* luv = (uint32*) sp->tbuf; float* xyz = (float*) op; while (n-- > 0) { LogLuv24toXYZ(*luv, xyz); xyz += 3; luv++; } } static void Luv24toLuv48(LogLuvState* sp, tidata_t op, int n) { uint32* luv = (uint32*) sp->tbuf; int16* luv3 = (int16*) op; while (n-- > 0) { double u, v; *luv3++ = (int16)((*luv >> 12 & 0xffd) + 13314); if (uv_decode(&u, &v, *luv&0x3fff) < 0) { u = U_NEU; v = V_NEU; } *luv3++ = (int16)(u * (1L<<15)); *luv3++ = (int16)(v * (1L<<15)); luv++; } } static void Luv24toRGB(LogLuvState* sp, tidata_t op, int n) { uint32* luv = (uint32*) sp->tbuf; uint8* rgb = (uint8*) op; while (n-- > 0) { float xyz[3]; LogLuv24toXYZ(*luv++, xyz); XYZtoRGB24(xyz, rgb); rgb += 3; } } static void Luv24fromXYZ(LogLuvState* sp, tidata_t op, int n) { uint32* luv = (uint32*) sp->tbuf; float* xyz = (float*) op; while (n-- > 0) { *luv++ = LogLuv24fromXYZ(xyz, sp->encode_meth); xyz += 3; } } static void Luv24fromLuv48(LogLuvState* sp, tidata_t op, int n) { uint32* luv = (uint32*) sp->tbuf; int16* luv3 = (int16*) op; while (n-- > 0) { int Le, Ce; if (luv3[0] <= 0) Le = 0; else if (luv3[0] >= (1<<12)+3314) Le = (1<<10) - 1; else if (sp->encode_meth == SGILOGENCODE_NODITHER) Le = (luv3[0]-3314) >> 2; else Le = itrunc(.25*(luv3[0]-3314.), sp->encode_meth); Ce = uv_encode((luv3[1]+.5)/(1<<15), (luv3[2]+.5)/(1<<15), sp->encode_meth); if (Ce < 0) /* never happens */ Ce = uv_encode(U_NEU, V_NEU, SGILOGENCODE_NODITHER); *luv++ = (uint32)Le << 14 | Ce; luv3 += 3; } } #if !LOGLUV_PUBLIC static #endif void LogLuv32toXYZ(uint32 p, float XYZ[3]) { double L, u, v, s, x, y; /* decode luminance */ L = LogL16toY((int)p >> 16); if (L <= 0.) { XYZ[0] = XYZ[1] = XYZ[2] = 0.; return; } /* decode color */ u = 1./UVSCALE * ((p>>8 & 0xff) + .5); v = 1./UVSCALE * ((p & 0xff) + .5); s = 1./(6.*u - 16.*v + 12.); x = 9.*u * s; y = 4.*v * s; /* convert to XYZ */ XYZ[0] = (float)(x/y * L); XYZ[1] = (float)L; XYZ[2] = (float)((1.-x-y)/y * L); } #if !LOGLUV_PUBLIC static #endif uint32 LogLuv32fromXYZ(float XYZ[3], int em) { unsigned int Le, ue, ve; double u, v, s; /* encode luminance */ Le = (unsigned int)LogL16fromY(XYZ[1], em); /* encode color */ s = XYZ[0] + 15.*XYZ[1] + 3.*XYZ[2]; if (!Le || s <= 0.) { u = U_NEU; v = V_NEU; } else { u = 4.*XYZ[0] / s; v = 9.*XYZ[1] / s; } if (u <= 0.) ue = 0; else ue = itrunc(UVSCALE*u, em); if (ue > 255) ue = 255; if (v <= 0.) ve = 0; else ve = itrunc(UVSCALE*v, em); if (ve > 255) ve = 255; /* combine encodings */ return (Le << 16 | ue << 8 | ve); } static void Luv32toXYZ(LogLuvState* sp, tidata_t op, int n) { uint32* luv = (uint32*) sp->tbuf; float* xyz = (float*) op; while (n-- > 0) { LogLuv32toXYZ(*luv++, xyz); xyz += 3; } } static void Luv32toLuv48(LogLuvState* sp, tidata_t op, int n) { uint32* luv = (uint32*) sp->tbuf; int16* luv3 = (int16*) op; while (n-- > 0) { double u, v; *luv3++ = (int16)(*luv >> 16); u = 1./UVSCALE * ((*luv>>8 & 0xff) + .5); v = 1./UVSCALE * ((*luv & 0xff) + .5); *luv3++ = (int16)(u * (1L<<15)); *luv3++ = (int16)(v * (1L<<15)); luv++; } } static void Luv32toRGB(LogLuvState* sp, tidata_t op, int n) { uint32* luv = (uint32*) sp->tbuf; uint8* rgb = (uint8*) op; while (n-- > 0) { float xyz[3]; LogLuv32toXYZ(*luv++, xyz); XYZtoRGB24(xyz, rgb); rgb += 3; } } static void Luv32fromXYZ(LogLuvState* sp, tidata_t op, int n) { uint32* luv = (uint32*) sp->tbuf; float* xyz = (float*) op; while (n-- > 0) { *luv++ = LogLuv32fromXYZ(xyz, sp->encode_meth); xyz += 3; } } static void Luv32fromLuv48(LogLuvState* sp, tidata_t op, int n) { uint32* luv = (uint32*) sp->tbuf; int16* luv3 = (int16*) op; if (sp->encode_meth == SGILOGENCODE_NODITHER) { while (n-- > 0) { *luv++ = (uint32)luv3[0] << 16 | (luv3[1]*(uint32)(UVSCALE+.5) >> 7 & 0xff00) | (luv3[2]*(uint32)(UVSCALE+.5) >> 15 & 0xff); luv3 += 3; } return; } while (n-- > 0) { *luv++ = (uint32)luv3[0] << 16 | (itrunc(luv3[1]*(UVSCALE/(1<<15)), sp->encode_meth) << 8 & 0xff00) | (itrunc(luv3[2]*(UVSCALE/(1<<15)), sp->encode_meth) & 0xff); luv3 += 3; } } static void _logLuvNop(LogLuvState* sp, tidata_t op, int n) { (void) sp; (void) op; (void) n; } static int LogL16GuessDataFmt(TIFFDirectory *td) { #define PACK(s,b,f) (((b)<<6)|((s)<<3)|(f)) switch (PACK(td->td_samplesperpixel, td->td_bitspersample, td->td_sampleformat)) { case PACK(1, 32, SAMPLEFORMAT_IEEEFP): return (SGILOGDATAFMT_FLOAT); case PACK(1, 16, SAMPLEFORMAT_VOID): case PACK(1, 16, SAMPLEFORMAT_INT): case PACK(1, 16, SAMPLEFORMAT_UINT): return (SGILOGDATAFMT_16BIT); case PACK(1, 8, SAMPLEFORMAT_VOID): case PACK(1, 8, SAMPLEFORMAT_UINT): return (SGILOGDATAFMT_8BIT); } #undef PACK return (SGILOGDATAFMT_UNKNOWN); } static uint32 multiply(size_t m1, size_t m2) { uint32 bytes = m1 * m2; if (m1 && bytes / m1 != m2) bytes = 0; return bytes; } static int LogL16InitState(TIFF* tif) { TIFFDirectory *td = &tif->tif_dir; LogLuvState* sp = DecoderState(tif); static const char module[] = "LogL16InitState"; assert(sp != NULL); assert(td->td_photometric == PHOTOMETRIC_LOGL); /* for some reason, we can't do this in TIFFInitLogL16 */ if (sp->user_datafmt == SGILOGDATAFMT_UNKNOWN) sp->user_datafmt = LogL16GuessDataFmt(td); switch (sp->user_datafmt) { case SGILOGDATAFMT_FLOAT: sp->pixel_size = sizeof (float); break; case SGILOGDATAFMT_16BIT: sp->pixel_size = sizeof (int16); break; case SGILOGDATAFMT_8BIT: sp->pixel_size = sizeof (uint8); break; default: TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "No support for converting user data format to LogL"); return (0); } sp->tbuflen = multiply(td->td_imagewidth, td->td_rowsperstrip); if (multiply(sp->tbuflen, sizeof (int16)) == 0 || (sp->tbuf = (tidata_t*) _TIFFmalloc(sp->tbuflen * sizeof (int16))) == NULL) { TIFFErrorExt(tif->tif_clientdata, module, "%s: No space for SGILog translation buffer", tif->tif_name); return (0); } return (1); } static int LogLuvGuessDataFmt(TIFFDirectory *td) { int guess; /* * If the user didn't tell us their datafmt, * take our best guess from the bitspersample. */ #define PACK(a,b) (((a)<<3)|(b)) switch (PACK(td->td_bitspersample, td->td_sampleformat)) { case PACK(32, SAMPLEFORMAT_IEEEFP): guess = SGILOGDATAFMT_FLOAT; break; case PACK(32, SAMPLEFORMAT_VOID): case PACK(32, SAMPLEFORMAT_UINT): case PACK(32, SAMPLEFORMAT_INT): guess = SGILOGDATAFMT_RAW; break; case PACK(16, SAMPLEFORMAT_VOID): case PACK(16, SAMPLEFORMAT_INT): case PACK(16, SAMPLEFORMAT_UINT): guess = SGILOGDATAFMT_16BIT; break; case PACK( 8, SAMPLEFORMAT_VOID): case PACK( 8, SAMPLEFORMAT_UINT): guess = SGILOGDATAFMT_8BIT; break; default: guess = SGILOGDATAFMT_UNKNOWN; break; #undef PACK } /* * Double-check samples per pixel. */ switch (td->td_samplesperpixel) { case 1: if (guess != SGILOGDATAFMT_RAW) guess = SGILOGDATAFMT_UNKNOWN; break; case 3: if (guess == SGILOGDATAFMT_RAW) guess = SGILOGDATAFMT_UNKNOWN; break; default: guess = SGILOGDATAFMT_UNKNOWN; break; } return (guess); } static int LogLuvInitState(TIFF* tif) { TIFFDirectory* td = &tif->tif_dir; LogLuvState* sp = DecoderState(tif); static const char module[] = "LogLuvInitState"; assert(sp != NULL); assert(td->td_photometric == PHOTOMETRIC_LOGLUV); /* for some reason, we can't do this in TIFFInitLogLuv */ if (td->td_planarconfig != PLANARCONFIG_CONTIG) { TIFFErrorExt(tif->tif_clientdata, module, "SGILog compression cannot handle non-contiguous data"); return (0); } if (sp->user_datafmt == SGILOGDATAFMT_UNKNOWN) sp->user_datafmt = LogLuvGuessDataFmt(td); switch (sp->user_datafmt) { case SGILOGDATAFMT_FLOAT: sp->pixel_size = 3*sizeof (float); break; case SGILOGDATAFMT_16BIT: sp->pixel_size = 3*sizeof (int16); break; case SGILOGDATAFMT_RAW: sp->pixel_size = sizeof (uint32); break; case SGILOGDATAFMT_8BIT: sp->pixel_size = 3*sizeof (uint8); break; default: TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "No support for converting user data format to LogLuv"); return (0); } sp->tbuflen = multiply(td->td_imagewidth, td->td_rowsperstrip); if (multiply(sp->tbuflen, sizeof (uint32)) == 0 || (sp->tbuf = (tidata_t*) _TIFFmalloc(sp->tbuflen * sizeof (uint32))) == NULL) { TIFFErrorExt(tif->tif_clientdata, module, "%s: No space for SGILog translation buffer", tif->tif_name); return (0); } return (1); } static int LogLuvSetupDecode(TIFF* tif) { LogLuvState* sp = DecoderState(tif); TIFFDirectory* td = &tif->tif_dir; tif->tif_postdecode = _TIFFNoPostDecode; switch (td->td_photometric) { case PHOTOMETRIC_LOGLUV: if (!LogLuvInitState(tif)) break; if (td->td_compression == COMPRESSION_SGILOG24) { tif->tif_decoderow = LogLuvDecode24; switch (sp->user_datafmt) { case SGILOGDATAFMT_FLOAT: sp->tfunc = Luv24toXYZ; break; case SGILOGDATAFMT_16BIT: sp->tfunc = Luv24toLuv48; break; case SGILOGDATAFMT_8BIT: sp->tfunc = Luv24toRGB; break; } } else { tif->tif_decoderow = LogLuvDecode32; switch (sp->user_datafmt) { case SGILOGDATAFMT_FLOAT: sp->tfunc = Luv32toXYZ; break; case SGILOGDATAFMT_16BIT: sp->tfunc = Luv32toLuv48; break; case SGILOGDATAFMT_8BIT: sp->tfunc = Luv32toRGB; break; } } return (1); case PHOTOMETRIC_LOGL: if (!LogL16InitState(tif)) break; tif->tif_decoderow = LogL16Decode; switch (sp->user_datafmt) { case SGILOGDATAFMT_FLOAT: sp->tfunc = L16toY; break; case SGILOGDATAFMT_8BIT: sp->tfunc = L16toGry; break; } return (1); default: TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Inappropriate photometric interpretation %d for SGILog compression; %s", td->td_photometric, "must be either LogLUV or LogL"); break; } return (0); } static int LogLuvSetupEncode(TIFF* tif) { LogLuvState* sp = EncoderState(tif); TIFFDirectory* td = &tif->tif_dir; switch (td->td_photometric) { case PHOTOMETRIC_LOGLUV: if (!LogLuvInitState(tif)) break; if (td->td_compression == COMPRESSION_SGILOG24) { tif->tif_encoderow = LogLuvEncode24; switch (sp->user_datafmt) { case SGILOGDATAFMT_FLOAT: sp->tfunc = Luv24fromXYZ; break; case SGILOGDATAFMT_16BIT: sp->tfunc = Luv24fromLuv48; break; case SGILOGDATAFMT_RAW: break; default: goto notsupported; } } else { tif->tif_encoderow = LogLuvEncode32; switch (sp->user_datafmt) { case SGILOGDATAFMT_FLOAT: sp->tfunc = Luv32fromXYZ; break; case SGILOGDATAFMT_16BIT: sp->tfunc = Luv32fromLuv48; break; case SGILOGDATAFMT_RAW: break; default: goto notsupported; } } break; case PHOTOMETRIC_LOGL: if (!LogL16InitState(tif)) break; tif->tif_encoderow = LogL16Encode; switch (sp->user_datafmt) { case SGILOGDATAFMT_FLOAT: sp->tfunc = L16fromY; break; case SGILOGDATAFMT_16BIT: break; default: goto notsupported; } break; default: TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Inappropriate photometric interpretation %d for SGILog compression; %s", td->td_photometric, "must be either LogLUV or LogL"); break; } return (1); notsupported: TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "SGILog compression supported only for %s, or raw data", td->td_photometric == PHOTOMETRIC_LOGL ? "Y, L" : "XYZ, Luv"); return (0); } static void LogLuvClose(TIFF* tif) { TIFFDirectory *td = &tif->tif_dir; /* * For consistency, we always want to write out the same * bitspersample and sampleformat for our TIFF file, * regardless of the data format being used by the application. * Since this routine is called after tags have been set but * before they have been recorded in the file, we reset them here. */ td->td_samplesperpixel = (td->td_photometric == PHOTOMETRIC_LOGL) ? 1 : 3; td->td_bitspersample = 16; td->td_sampleformat = SAMPLEFORMAT_INT; } static void LogLuvCleanup(TIFF* tif) { LogLuvState* sp = (LogLuvState *)tif->tif_data; assert(sp != 0); tif->tif_tagmethods.vgetfield = sp->vgetparent; tif->tif_tagmethods.vsetfield = sp->vsetparent; if (sp->tbuf) _TIFFfree(sp->tbuf); _TIFFfree(sp); tif->tif_data = NULL; _TIFFSetDefaultCompressionState(tif); } static int LogLuvVSetField(TIFF* tif, ttag_t tag, va_list ap) { LogLuvState* sp = DecoderState(tif); int bps, fmt; switch (tag) { case TIFFTAG_SGILOGDATAFMT: sp->user_datafmt = va_arg(ap, int); /* * Tweak the TIFF header so that the rest of libtiff knows what * size of data will be passed between app and library, and * assume that the app knows what it is doing and is not * confused by these header manipulations... */ switch (sp->user_datafmt) { case SGILOGDATAFMT_FLOAT: bps = 32, fmt = SAMPLEFORMAT_IEEEFP; break; case SGILOGDATAFMT_16BIT: bps = 16, fmt = SAMPLEFORMAT_INT; break; case SGILOGDATAFMT_RAW: bps = 32, fmt = SAMPLEFORMAT_UINT; TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, 1); break; case SGILOGDATAFMT_8BIT: bps = 8, fmt = SAMPLEFORMAT_UINT; break; default: TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Unknown data format %d for LogLuv compression", sp->user_datafmt); return (0); } TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, bps); TIFFSetField(tif, TIFFTAG_SAMPLEFORMAT, fmt); /* * Must recalculate sizes should bits/sample change. */ tif->tif_tilesize = isTiled(tif) ? TIFFTileSize(tif) : (tsize_t) -1; tif->tif_scanlinesize = TIFFScanlineSize(tif); return (1); case TIFFTAG_SGILOGENCODE: sp->encode_meth = va_arg(ap, int); if (sp->encode_meth != SGILOGENCODE_NODITHER && sp->encode_meth != SGILOGENCODE_RANDITHER) { TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Unknown encoding %d for LogLuv compression", sp->encode_meth); return (0); } return (1); default: return (*sp->vsetparent)(tif, tag, ap); } } static int LogLuvVGetField(TIFF* tif, ttag_t tag, va_list ap) { LogLuvState *sp = (LogLuvState *)tif->tif_data; switch (tag) { case TIFFTAG_SGILOGDATAFMT: *va_arg(ap, int*) = sp->user_datafmt; return (1); default: return (*sp->vgetparent)(tif, tag, ap); } } static const TIFFFieldInfo LogLuvFieldInfo[] = { { TIFFTAG_SGILOGDATAFMT, 0, 0, TIFF_SHORT, FIELD_PSEUDO, TRUE, FALSE, "SGILogDataFmt"}, { TIFFTAG_SGILOGENCODE, 0, 0, TIFF_SHORT, FIELD_PSEUDO, TRUE, FALSE, "SGILogEncode"} }; int TIFFInitSGILog(TIFF* tif, int scheme) { static const char module[] = "TIFFInitSGILog"; LogLuvState* sp; assert(scheme == COMPRESSION_SGILOG24 || scheme == COMPRESSION_SGILOG); /* * Allocate state block so tag methods have storage to record values. */ tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (LogLuvState)); if (tif->tif_data == NULL) goto bad; sp = (LogLuvState*) tif->tif_data; _TIFFmemset((tdata_t)sp, 0, sizeof (*sp)); sp->user_datafmt = SGILOGDATAFMT_UNKNOWN; sp->encode_meth = (scheme == COMPRESSION_SGILOG24) ? SGILOGENCODE_RANDITHER : SGILOGENCODE_NODITHER; sp->tfunc = _logLuvNop; /* * Install codec methods. * NB: tif_decoderow & tif_encoderow are filled * in at setup time. */ tif->tif_setupdecode = LogLuvSetupDecode; tif->tif_decodestrip = LogLuvDecodeStrip; tif->tif_decodetile = LogLuvDecodeTile; tif->tif_setupencode = LogLuvSetupEncode; tif->tif_encodestrip = LogLuvEncodeStrip; tif->tif_encodetile = LogLuvEncodeTile; tif->tif_close = LogLuvClose; tif->tif_cleanup = LogLuvCleanup; /* override SetField so we can handle our private pseudo-tag */ _TIFFMergeFieldInfo(tif, LogLuvFieldInfo, TIFFArrayCount(LogLuvFieldInfo)); sp->vgetparent = tif->tif_tagmethods.vgetfield; tif->tif_tagmethods.vgetfield = LogLuvVGetField; /* hook for codec tags */ sp->vsetparent = tif->tif_tagmethods.vsetfield; tif->tif_tagmethods.vsetfield = LogLuvVSetField; /* hook for codec tags */ return (1); bad: TIFFErrorExt(tif->tif_clientdata, module, "%s: No space for LogLuv state block", tif->tif_name); return (0); } #endif /* LOGLUV_SUPPORT */ /* vim: set ts=8 sts=8 sw=8 noet: */