opencv/3rdparty/libtiff/tif_luv.c

1601 lines
40 KiB
C

/* $Id: tif_luv.c,v 1.1 2005-06-17 13:54:52 vp153 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 <stdio.h>
#include <stdlib.h>
#include <math.h>
/*
* 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 N(a) (sizeof(a)/sizeof(a[0]))
#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) {
TIFFError(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) {
TIFFError(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) {
TIFFError(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:
TIFFError(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) {
TIFFError(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) {
TIFFError(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:
TIFFError(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) {
TIFFError(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:
TIFFError(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:
TIFFError(tif->tif_name,
"Inappropriate photometric interpretation %d for SGILog compression; %s",
td->td_photometric, "must be either LogLUV or LogL");
break;
}
return (1);
notsupported:
TIFFError(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;
if (sp) {
if (sp->tbuf)
_TIFFfree(sp->tbuf);
_TIFFfree(sp);
tif->tif_data = NULL;
}
}
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:
TIFFError(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) {
TIFFError(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, N(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:
TIFFError(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: */