Initial import of argyll version 1.5.1-8debian/1.5.1-8

1 files changed, 1371 insertions, 0 deletions

diff --git a/tiff/libtiff/tif_pixarlog.c b/tiff/libtiff/tif_pixarlog.c
new file mode 100644
index 0000000..ed8eb40
--- /dev/null
+++ b/tiff/libtiff/tif_pixarlog.c
@@ -0,0 +1,1371 @@
+/* $Id: tif_pixarlog.c,v 1.15.2.4 2010-06-08 18:50:42 bfriesen Exp $ */
+
+/*
+ * Copyright (c) 1996-1997 Sam Leffler
+ * Copyright (c) 1996 Pixar
+ *
+ * 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
+ * Pixar, Sam Leffler and Silicon Graphics may not be used in any advertising or
+ * publicity relating to the software without the specific, prior written
+ * permission of Pixar, Sam Leffler 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 PIXAR, SAM LEFFLER 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 PIXARLOG_SUPPORT
+
+/*
+ * TIFF Library.
+ * PixarLog Compression Support
+ *
+ * Contributed by Dan McCoy.
+ *
+ * PixarLog film support uses the TIFF library to store companded
+ * 11 bit values into a tiff file, which are compressed using the 
+ * zip compressor.  
+ *
+ * The codec can take as input and produce as output 32-bit IEEE float values 
+ * as well as 16-bit or 8-bit unsigned integer values.
+ *
+ * On writing any of the above are converted into the internal
+ * 11-bit log format.   In the case of  8 and 16 bit values, the
+ * input is assumed to be unsigned linear color values that represent
+ * the range 0-1.  In the case of IEEE values, the 0-1 range is assumed to
+ * be the normal linear color range, in addition over 1 values are
+ * accepted up to a value of about 25.0 to encode "hot" hightlights and such.
+ * The encoding is lossless for 8-bit values, slightly lossy for the
+ * other bit depths.  The actual color precision should be better
+ * than the human eye can perceive with extra room to allow for
+ * error introduced by further image computation.  As with any quantized
+ * color format, it is possible to perform image calculations which
+ * expose the quantization error. This format should certainly be less 
+ * susceptable to such errors than standard 8-bit encodings, but more
+ * susceptable than straight 16-bit or 32-bit encodings.
+ *
+ * On reading the internal format is converted to the desired output format.
+ * The program can request which format it desires by setting the internal
+ * pseudo tag TIFFTAG_PIXARLOGDATAFMT to one of these possible values:
+ *  PIXARLOGDATAFMT_FLOAT     = provide IEEE float values.
+ *  PIXARLOGDATAFMT_16BIT     = provide unsigned 16-bit integer values
+ *  PIXARLOGDATAFMT_8BIT      = provide unsigned 8-bit integer values
+ *
+ * alternately PIXARLOGDATAFMT_8BITABGR provides unsigned 8-bit integer
+ * values with the difference that if there are exactly three or four channels
+ * (rgb or rgba) it swaps the channel order (bgr or abgr).
+ *
+ * PIXARLOGDATAFMT_11BITLOG provides the internal encoding directly
+ * packed in 16-bit values.   However no tools are supplied for interpreting
+ * these values.
+ *
+ * "hot" (over 1.0) areas written in floating point get clamped to
+ * 1.0 in the integer data types.
+ *
+ * When the file is closed after writing, the bit depth and sample format
+ * are set always to appear as if 8-bit data has been written into it.
+ * That way a naive program unaware of the particulars of the encoding
+ * gets the format it is most likely able to handle.
+ *
+ * The codec does it's own horizontal differencing step on the coded
+ * values so the libraries predictor stuff should be turned off.
+ * The codec also handle byte swapping the encoded values as necessary
+ * since the library does not have the information necessary
+ * to know the bit depth of the raw unencoded buffer.
+ * 
+ */
+
+#include "tif_predict.h"
+#include "zlib.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+
+/* Tables for converting to/from 11 bit coded values */
+
+#define  TSIZE	 2048		/* decode table size (11-bit tokens) */
+#define  TSIZEP1 2049		/* Plus one for slop */
+#define  ONE	 1250		/* token value of 1.0 exactly */
+#define  RATIO	 1.004		/* nominal ratio for log part */
+
+#define CODE_MASK 0x7ff         /* 11 bits. */
+
+static float  Fltsize;
+static float  LogK1, LogK2;
+
+#define REPEAT(n, op)   { int i; i=n; do { i--; op; } while (i>0); }
+
+static void
+horizontalAccumulateF(uint16 *wp, int n, int stride, float *op, 
+	float *ToLinearF)
+{
+    register unsigned int  cr, cg, cb, ca, mask;
+    register float  t0, t1, t2, t3;
+
+    if (n >= stride) {
+	mask = CODE_MASK;
+	if (stride == 3) {
+	    t0 = ToLinearF[cr = wp[0]];
+	    t1 = ToLinearF[cg = wp[1]];
+	    t2 = ToLinearF[cb = wp[2]];
+	    op[0] = t0;
+	    op[1] = t1;
+	    op[2] = t2;
+	    n -= 3;
+	    while (n > 0) {
+		wp += 3;
+		op += 3;
+		n -= 3;
+		t0 = ToLinearF[(cr += wp[0]) & mask];
+		t1 = ToLinearF[(cg += wp[1]) & mask];
+		t2 = ToLinearF[(cb += wp[2]) & mask];
+		op[0] = t0;
+		op[1] = t1;
+		op[2] = t2;
+	    }
+	} else if (stride == 4) {
+	    t0 = ToLinearF[cr = wp[0]];
+	    t1 = ToLinearF[cg = wp[1]];
+	    t2 = ToLinearF[cb = wp[2]];
+	    t3 = ToLinearF[ca = wp[3]];
+	    op[0] = t0;
+	    op[1] = t1;
+	    op[2] = t2;
+	    op[3] = t3;
+	    n -= 4;
+	    while (n > 0) {
+		wp += 4;
+		op += 4;
+		n -= 4;
+		t0 = ToLinearF[(cr += wp[0]) & mask];
+		t1 = ToLinearF[(cg += wp[1]) & mask];
+		t2 = ToLinearF[(cb += wp[2]) & mask];
+		t3 = ToLinearF[(ca += wp[3]) & mask];
+		op[0] = t0;
+		op[1] = t1;
+		op[2] = t2;
+		op[3] = t3;
+	    }
+	} else {
+	    REPEAT(stride, *op = ToLinearF[*wp&mask]; wp++; op++)
+	    n -= stride;
+	    while (n > 0) {
+		REPEAT(stride,
+		    wp[stride] += *wp; *op = ToLinearF[*wp&mask]; wp++; op++)
+		n -= stride;
+	    }
+	}
+    }
+}
+
+static void
+horizontalAccumulate12(uint16 *wp, int n, int stride, int16 *op,
+	float *ToLinearF)
+{
+    register unsigned int  cr, cg, cb, ca, mask;
+    register float  t0, t1, t2, t3;
+
+#define SCALE12 2048.0F
+#define CLAMP12(t) (((t) < 3071) ? (uint16) (t) : 3071)
+
+    if (n >= stride) {
+	mask = CODE_MASK;
+	if (stride == 3) {
+	    t0 = ToLinearF[cr = wp[0]] * SCALE12;
+	    t1 = ToLinearF[cg = wp[1]] * SCALE12;
+	    t2 = ToLinearF[cb = wp[2]] * SCALE12;
+	    op[0] = CLAMP12(t0);
+	    op[1] = CLAMP12(t1);
+	    op[2] = CLAMP12(t2);
+	    n -= 3;
+	    while (n > 0) {
+		wp += 3;
+		op += 3;
+		n -= 3;
+		t0 = ToLinearF[(cr += wp[0]) & mask] * SCALE12;
+		t1 = ToLinearF[(cg += wp[1]) & mask] * SCALE12;
+		t2 = ToLinearF[(cb += wp[2]) & mask] * SCALE12;
+		op[0] = CLAMP12(t0);
+		op[1] = CLAMP12(t1);
+		op[2] = CLAMP12(t2);
+	    }
+	} else if (stride == 4) {
+	    t0 = ToLinearF[cr = wp[0]] * SCALE12;
+	    t1 = ToLinearF[cg = wp[1]] * SCALE12;
+	    t2 = ToLinearF[cb = wp[2]] * SCALE12;
+	    t3 = ToLinearF[ca = wp[3]] * SCALE12;
+	    op[0] = CLAMP12(t0);
+	    op[1] = CLAMP12(t1);
+	    op[2] = CLAMP12(t2);
+	    op[3] = CLAMP12(t3);
+	    n -= 4;
+	    while (n > 0) {
+		wp += 4;
+		op += 4;
+		n -= 4;
+		t0 = ToLinearF[(cr += wp[0]) & mask] * SCALE12;
+		t1 = ToLinearF[(cg += wp[1]) & mask] * SCALE12;
+		t2 = ToLinearF[(cb += wp[2]) & mask] * SCALE12;
+		t3 = ToLinearF[(ca += wp[3]) & mask] * SCALE12;
+		op[0] = CLAMP12(t0);
+		op[1] = CLAMP12(t1);
+		op[2] = CLAMP12(t2);
+		op[3] = CLAMP12(t3);
+	    }
+	} else {
+	    REPEAT(stride, t0 = ToLinearF[*wp&mask] * SCALE12;
+                           *op = CLAMP12(t0); wp++; op++)
+	    n -= stride;
+	    while (n > 0) {
+		REPEAT(stride,
+		    wp[stride] += *wp; t0 = ToLinearF[wp[stride]&mask]*SCALE12;
+		    *op = CLAMP12(t0);  wp++; op++)
+		n -= stride;
+	    }
+	}
+    }
+}
+
+static void
+horizontalAccumulate16(uint16 *wp, int n, int stride, uint16 *op,
+	uint16 *ToLinear16)
+{
+    register unsigned int  cr, cg, cb, ca, mask;
+
+    if (n >= stride) {
+	mask = CODE_MASK;
+	if (stride == 3) {
+	    op[0] = ToLinear16[cr = wp[0]];
+	    op[1] = ToLinear16[cg = wp[1]];
+	    op[2] = ToLinear16[cb = wp[2]];
+	    n -= 3;
+	    while (n > 0) {
+		wp += 3;
+		op += 3;
+		n -= 3;
+		op[0] = ToLinear16[(cr += wp[0]) & mask];
+		op[1] = ToLinear16[(cg += wp[1]) & mask];
+		op[2] = ToLinear16[(cb += wp[2]) & mask];
+	    }
+	} else if (stride == 4) {
+	    op[0] = ToLinear16[cr = wp[0]];
+	    op[1] = ToLinear16[cg = wp[1]];
+	    op[2] = ToLinear16[cb = wp[2]];
+	    op[3] = ToLinear16[ca = wp[3]];
+	    n -= 4;
+	    while (n > 0) {
+		wp += 4;
+		op += 4;
+		n -= 4;
+		op[0] = ToLinear16[(cr += wp[0]) & mask];
+		op[1] = ToLinear16[(cg += wp[1]) & mask];
+		op[2] = ToLinear16[(cb += wp[2]) & mask];
+		op[3] = ToLinear16[(ca += wp[3]) & mask];
+	    }
+	} else {
+	    REPEAT(stride, *op = ToLinear16[*wp&mask]; wp++; op++)
+	    n -= stride;
+	    while (n > 0) {
+		REPEAT(stride,
+		    wp[stride] += *wp; *op = ToLinear16[*wp&mask]; wp++; op++)
+		n -= stride;
+	    }
+	}
+    }
+}
+
+/* 
+ * Returns the log encoded 11-bit values with the horizontal
+ * differencing undone.
+ */
+static void
+horizontalAccumulate11(uint16 *wp, int n, int stride, uint16 *op)
+{
+    register unsigned int  cr, cg, cb, ca, mask;
+
+    if (n >= stride) {
+	mask = CODE_MASK;
+	if (stride == 3) {
+	    op[0] = cr = wp[0];  op[1] = cg = wp[1];  op[2] = cb = wp[2];
+	    n -= 3;
+	    while (n > 0) {
+		wp += 3;
+		op += 3;
+		n -= 3;
+		op[0] = (cr += wp[0]) & mask;
+		op[1] = (cg += wp[1]) & mask;
+		op[2] = (cb += wp[2]) & mask;
+	    }
+	} else if (stride == 4) {
+	    op[0] = cr = wp[0];  op[1] = cg = wp[1];
+	    op[2] = cb = wp[2];  op[3] = ca = wp[3];
+	    n -= 4;
+	    while (n > 0) {
+		wp += 4;
+		op += 4;
+		n -= 4;
+		op[0] = (cr += wp[0]) & mask;
+		op[1] = (cg += wp[1]) & mask;
+		op[2] = (cb += wp[2]) & mask;
+		op[3] = (ca += wp[3]) & mask;
+	    } 
+	} else {
+	    REPEAT(stride, *op = *wp&mask; wp++; op++)
+	    n -= stride;
+	    while (n > 0) {
+		REPEAT(stride,
+		    wp[stride] += *wp; *op = *wp&mask; wp++; op++)
+		n -= stride;
+	    }
+	}
+    }
+}
+
+static void
+horizontalAccumulate8(uint16 *wp, int n, int stride, unsigned char *op,
+	unsigned char *ToLinear8)
+{
+    register unsigned int  cr, cg, cb, ca, mask;
+
+    if (n >= stride) {
+	mask = CODE_MASK;
+	if (stride == 3) {
+	    op[0] = ToLinear8[cr = wp[0]];
+	    op[1] = ToLinear8[cg = wp[1]];
+	    op[2] = ToLinear8[cb = wp[2]];
+	    n -= 3;
+	    while (n > 0) {
+		n -= 3;
+		wp += 3;
+		op += 3;
+		op[0] = ToLinear8[(cr += wp[0]) & mask];
+		op[1] = ToLinear8[(cg += wp[1]) & mask];
+		op[2] = ToLinear8[(cb += wp[2]) & mask];
+	    }
+	} else if (stride == 4) {
+	    op[0] = ToLinear8[cr = wp[0]];
+	    op[1] = ToLinear8[cg = wp[1]];
+	    op[2] = ToLinear8[cb = wp[2]];
+	    op[3] = ToLinear8[ca = wp[3]];
+	    n -= 4;
+	    while (n > 0) {
+		n -= 4;
+		wp += 4;
+		op += 4;
+		op[0] = ToLinear8[(cr += wp[0]) & mask];
+		op[1] = ToLinear8[(cg += wp[1]) & mask];
+		op[2] = ToLinear8[(cb += wp[2]) & mask];
+		op[3] = ToLinear8[(ca += wp[3]) & mask];
+	    }
+	} else {
+	    REPEAT(stride, *op = ToLinear8[*wp&mask]; wp++; op++)
+	    n -= stride;
+	    while (n > 0) {
+		REPEAT(stride,
+		    wp[stride] += *wp; *op = ToLinear8[*wp&mask]; wp++; op++)
+		n -= stride;
+	    }
+	}
+    }
+}
+
+
+static void
+horizontalAccumulate8abgr(uint16 *wp, int n, int stride, unsigned char *op,
+	unsigned char *ToLinear8)
+{
+    register unsigned int  cr, cg, cb, ca, mask;
+    register unsigned char  t0, t1, t2, t3;
+
+    if (n >= stride) {
+	mask = CODE_MASK;
+	if (stride == 3) {
+	    op[0] = 0;
+	    t1 = ToLinear8[cb = wp[2]];
+	    t2 = ToLinear8[cg = wp[1]];
+	    t3 = ToLinear8[cr = wp[0]];
+	    op[1] = t1;
+	    op[2] = t2;
+	    op[3] = t3;
+	    n -= 3;
+	    while (n > 0) {
+		n -= 3;
+		wp += 3;
+		op += 4;
+		op[0] = 0;
+		t1 = ToLinear8[(cb += wp[2]) & mask];
+		t2 = ToLinear8[(cg += wp[1]) & mask];
+		t3 = ToLinear8[(cr += wp[0]) & mask];
+		op[1] = t1;
+		op[2] = t2;
+		op[3] = t3;
+	    }
+	} else if (stride == 4) {
+	    t0 = ToLinear8[ca = wp[3]];
+	    t1 = ToLinear8[cb = wp[2]];
+	    t2 = ToLinear8[cg = wp[1]];
+	    t3 = ToLinear8[cr = wp[0]];
+	    op[0] = t0;
+	    op[1] = t1;
+	    op[2] = t2;
+	    op[3] = t3;
+	    n -= 4;
+	    while (n > 0) {
+		n -= 4;
+		wp += 4;
+		op += 4;
+		t0 = ToLinear8[(ca += wp[3]) & mask];
+		t1 = ToLinear8[(cb += wp[2]) & mask];
+		t2 = ToLinear8[(cg += wp[1]) & mask];
+		t3 = ToLinear8[(cr += wp[0]) & mask];
+		op[0] = t0;
+		op[1] = t1;
+		op[2] = t2;
+		op[3] = t3;
+	    }
+	} else {
+	    REPEAT(stride, *op = ToLinear8[*wp&mask]; wp++; op++)
+	    n -= stride;
+	    while (n > 0) {
+		REPEAT(stride,
+		    wp[stride] += *wp; *op = ToLinear8[*wp&mask]; wp++; op++)
+		n -= stride;
+	    }
+	}
+    }
+}
+
+/*
+ * State block for each open TIFF
+ * file using PixarLog compression/decompression.
+ */
+typedef	struct {
+	TIFFPredictorState	predict;
+	z_stream		stream;
+	uint16			*tbuf; 
+	uint16			stride;
+	int			state;
+	int			user_datafmt;
+	int			quality;
+#define PLSTATE_INIT 1
+
+	TIFFVSetMethod		vgetparent;	/* super-class method */
+	TIFFVSetMethod		vsetparent;	/* super-class method */
+
+	float *ToLinearF;
+	uint16 *ToLinear16;
+	unsigned char *ToLinear8;
+	uint16  *FromLT2;
+	uint16  *From14; /* Really for 16-bit data, but we shift down 2 */
+	uint16  *From8;
+	
+} PixarLogState;
+
+static int
+PixarLogMakeTables(PixarLogState *sp)
+{
+
+/*
+ *    We make several tables here to convert between various external
+ *    representations (float, 16-bit, and 8-bit) and the internal
+ *    11-bit companded representation.  The 11-bit representation has two
+ *    distinct regions.  A linear bottom end up through .018316 in steps
+ *    of about .000073, and a region of constant ratio up to about 25.
+ *    These floating point numbers are stored in the main table ToLinearF. 
+ *    All other tables are derived from this one.  The tables (and the
+ *    ratios) are continuous at the internal seam.
+ */
+
+    int  nlin, lt2size;
+    int  i, j;
+    double  b, c, linstep, v;
+    float *ToLinearF;
+    uint16 *ToLinear16;
+    unsigned char *ToLinear8;
+    uint16  *FromLT2;
+    uint16  *From14; /* Really for 16-bit data, but we shift down 2 */
+    uint16  *From8;
+
+    c = log(RATIO);	
+    nlin = (int)(1./c);	/* nlin must be an integer */
+    c = 1./nlin;
+    b = exp(-c*ONE);	/* multiplicative scale factor [b*exp(c*ONE) = 1] */
+    linstep = b*c*exp(1.);
+
+    LogK1 = (float)(1./c);	/* if (v >= 2)  token = k1*log(v*k2) */
+    LogK2 = (float)(1./b);
+    lt2size = (int)(2./linstep) + 1;
+    FromLT2 = (uint16 *)_TIFFmalloc(lt2size*sizeof(uint16));
+    From14 = (uint16 *)_TIFFmalloc(16384*sizeof(uint16));
+    From8 = (uint16 *)_TIFFmalloc(256*sizeof(uint16));
+    ToLinearF = (float *)_TIFFmalloc(TSIZEP1 * sizeof(float));
+    ToLinear16 = (uint16 *)_TIFFmalloc(TSIZEP1 * sizeof(uint16));
+    ToLinear8 = (unsigned char *)_TIFFmalloc(TSIZEP1 * sizeof(unsigned char));
+    if (FromLT2 == NULL || From14  == NULL || From8   == NULL ||
+	 ToLinearF == NULL || ToLinear16 == NULL || ToLinear8 == NULL) {
+	if (FromLT2) _TIFFfree(FromLT2);
+	if (From14) _TIFFfree(From14);
+	if (From8) _TIFFfree(From8);
+	if (ToLinearF) _TIFFfree(ToLinearF);
+	if (ToLinear16) _TIFFfree(ToLinear16);
+	if (ToLinear8) _TIFFfree(ToLinear8);
+	sp->FromLT2 = NULL;
+	sp->From14 = NULL;
+	sp->From8 = NULL;
+	sp->ToLinearF = NULL;
+	sp->ToLinear16 = NULL;
+	sp->ToLinear8 = NULL;
+	return 0;
+    }
+
+    j = 0;
+
+    for (i = 0; i < nlin; i++)  {
+	v = i * linstep;
+	ToLinearF[j++] = (float)v;
+    }
+
+    for (i = nlin; i < TSIZE; i++)
+	ToLinearF[j++] = (float)(b*exp(c*i));
+
+    ToLinearF[2048] = ToLinearF[2047];
+
+    for (i = 0; i < TSIZEP1; i++)  {
+	v = ToLinearF[i]*65535.0 + 0.5;
+	ToLinear16[i] = (v > 65535.0) ? 65535 : (uint16)v;
+	v = ToLinearF[i]*255.0  + 0.5;
+	ToLinear8[i]  = (v > 255.0) ? 255 : (unsigned char)v;
+    }
+
+    j = 0;
+    for (i = 0; i < lt2size; i++)  {
+	if ((i*linstep)*(i*linstep) > ToLinearF[j]*ToLinearF[j+1])
+	    j++;
+	FromLT2[i] = j;
+    }
+
+    /*
+     * Since we lose info anyway on 16-bit data, we set up a 14-bit
+     * table and shift 16-bit values down two bits on input.
+     * saves a little table space.
+     */
+    j = 0;
+    for (i = 0; i < 16384; i++)  {
+	while ((i/16383.)*(i/16383.) > ToLinearF[j]*ToLinearF[j+1])
+	    j++;
+	From14[i] = j;
+    }
+
+    j = 0;
+    for (i = 0; i < 256; i++)  {
+	while ((i/255.)*(i/255.) > ToLinearF[j]*ToLinearF[j+1])
+	    j++;
+	From8[i] = j;
+    }
+
+    Fltsize = (float)(lt2size/2);
+
+    sp->ToLinearF = ToLinearF;
+    sp->ToLinear16 = ToLinear16;
+    sp->ToLinear8 = ToLinear8;
+    sp->FromLT2 = FromLT2;
+    sp->From14 = From14;
+    sp->From8 = From8;
+
+    return 1;
+}
+
+#define	DecoderState(tif)	((PixarLogState*) (tif)->tif_data)
+#define	EncoderState(tif)	((PixarLogState*) (tif)->tif_data)
+
+static	int PixarLogEncode(TIFF*, tidata_t, tsize_t, tsample_t);
+static	int PixarLogDecode(TIFF*, tidata_t, tsize_t, tsample_t);
+
+#define PIXARLOGDATAFMT_UNKNOWN	-1
+
+static int
+PixarLogGuessDataFmt(TIFFDirectory *td)
+{
+	int guess = PIXARLOGDATAFMT_UNKNOWN;
+	int format = td->td_sampleformat;
+
+	/* If the user didn't tell us his datafmt,
+	 * take our best guess from the bitspersample.
+	 */
+	switch (td->td_bitspersample) {
+	 case 32:
+		if (format == SAMPLEFORMAT_IEEEFP)
+			guess = PIXARLOGDATAFMT_FLOAT;
+		break;
+	 case 16:
+		if (format == SAMPLEFORMAT_VOID || format == SAMPLEFORMAT_UINT)
+			guess = PIXARLOGDATAFMT_16BIT;
+		break;
+	 case 12:
+		if (format == SAMPLEFORMAT_VOID || format == SAMPLEFORMAT_INT)
+			guess = PIXARLOGDATAFMT_12BITPICIO;
+		break;
+	 case 11:
+		if (format == SAMPLEFORMAT_VOID || format == SAMPLEFORMAT_UINT)
+			guess = PIXARLOGDATAFMT_11BITLOG;
+		break;
+	 case 8:
+		if (format == SAMPLEFORMAT_VOID || format == SAMPLEFORMAT_UINT)
+			guess = PIXARLOGDATAFMT_8BIT;
+		break;
+	}
+
+	return guess;
+}
+
+static uint32
+multiply(size_t m1, size_t m2)
+{
+	uint32	bytes = m1 * m2;
+
+	if (m1 && bytes / m1 != m2)
+		bytes = 0;
+
+	return bytes;
+}
+
+static int
+PixarLogSetupDecode(TIFF* tif)
+{
+	TIFFDirectory *td = &tif->tif_dir;
+	PixarLogState* sp = DecoderState(tif);
+	tsize_t tbuf_size;
+	static const char module[] = "PixarLogSetupDecode";
+
+	assert(sp != NULL);
+
+	/* Make sure no byte swapping happens on the data
+	 * after decompression. */
+	tif->tif_postdecode = _TIFFNoPostDecode;
+
+	/* for some reason, we can't do this in TIFFInitPixarLog */
+
+	sp->stride = (td->td_planarconfig == PLANARCONFIG_CONTIG ?
+	    td->td_samplesperpixel : 1);
+	tbuf_size = multiply(multiply(multiply(sp->stride, td->td_imagewidth),
+				      td->td_rowsperstrip), sizeof(uint16));
+	if (tbuf_size == 0)
+		return (0);
+	sp->tbuf = (uint16 *) _TIFFmalloc(tbuf_size);
+	if (sp->tbuf == NULL)
+		return (0);
+	if (sp->user_datafmt == PIXARLOGDATAFMT_UNKNOWN)
+		sp->user_datafmt = PixarLogGuessDataFmt(td);
+	if (sp->user_datafmt == PIXARLOGDATAFMT_UNKNOWN) {
+		TIFFErrorExt(tif->tif_clientdata, module,
+			"PixarLog compression can't handle bits depth/data format combination (depth: %d)", 
+			td->td_bitspersample);
+		return (0);
+	}
+
+	if (inflateInit(&sp->stream) != Z_OK) {
+		TIFFErrorExt(tif->tif_clientdata, module, "%s: %s", tif->tif_name, sp->stream.msg);
+		return (0);
+	} else {
+		sp->state |= PLSTATE_INIT;
+		return (1);
+	}
+}
+
+/*
+ * Setup state for decoding a strip.
+ */
+static int
+PixarLogPreDecode(TIFF* tif, tsample_t s)
+{
+	PixarLogState* sp = DecoderState(tif);
+
+	(void) s;
+	assert(sp != NULL);
+	sp->stream.next_in = tif->tif_rawdata;
+	sp->stream.avail_in = tif->tif_rawcc;
+	return (inflateReset(&sp->stream) == Z_OK);
+}
+
+static int
+PixarLogDecode(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
+{
+	TIFFDirectory *td = &tif->tif_dir;
+	PixarLogState* sp = DecoderState(tif);
+	static const char module[] = "PixarLogDecode";
+	int i, nsamples, llen;
+	uint16 *up;
+
+	switch (sp->user_datafmt) {
+	case PIXARLOGDATAFMT_FLOAT:
+		nsamples = occ / sizeof(float);	/* XXX float == 32 bits */
+		break;
+	case PIXARLOGDATAFMT_16BIT:
+	case PIXARLOGDATAFMT_12BITPICIO:
+	case PIXARLOGDATAFMT_11BITLOG:
+		nsamples = occ / sizeof(uint16); /* XXX uint16 == 16 bits */
+		break;
+	case PIXARLOGDATAFMT_8BIT:
+	case PIXARLOGDATAFMT_8BITABGR:
+		nsamples = occ;
+		break;
+	default:
+		TIFFErrorExt(tif->tif_clientdata, tif->tif_name,
+			"%d bit input not supported in PixarLog",
+			td->td_bitspersample);
+		return 0;
+	}
+
+	llen = sp->stride * td->td_imagewidth;
+
+	(void) s;
+	assert(sp != NULL);
+	sp->stream.next_out = (unsigned char *) sp->tbuf;
+	sp->stream.avail_out = nsamples * sizeof(uint16);
+	do {
+		int state = inflate(&sp->stream, Z_PARTIAL_FLUSH);
+		if (state == Z_STREAM_END) {
+			break;			/* XXX */
+		}
+		if (state == Z_DATA_ERROR) {
+			TIFFErrorExt(tif->tif_clientdata, module,
+			    "%s: Decoding error at scanline %d, %s",
+			    tif->tif_name, tif->tif_row, sp->stream.msg);
+			if (inflateSync(&sp->stream) != Z_OK)
+				return (0);
+			continue;
+		}
+		if (state != Z_OK) {
+			TIFFErrorExt(tif->tif_clientdata, module, "%s: zlib error: %s",
+			    tif->tif_name, sp->stream.msg);
+			return (0);
+		}
+	} while (sp->stream.avail_out > 0);
+
+	/* hopefully, we got all the bytes we needed */
+	if (sp->stream.avail_out != 0) {
+		TIFFErrorExt(tif->tif_clientdata, module,
+		    "%s: Not enough data at scanline %d (short %d bytes)",
+		    tif->tif_name, tif->tif_row, sp->stream.avail_out);
+		return (0);
+	}
+
+	up = sp->tbuf;
+	/* Swap bytes in the data if from a different endian machine. */
+	if (tif->tif_flags & TIFF_SWAB)
+		TIFFSwabArrayOfShort(up, nsamples);
+
+	/* 
+	 * if llen is not an exact multiple of nsamples, the decode operation
+	 * may overflow the output buffer, so truncate it enough to prevent
+	 * that but still salvage as much data as possible.
+	 */
+	if (nsamples % llen) { 
+		TIFFWarningExt(tif->tif_clientdata, module,
+			"%s: stride %d is not a multiple of sample count, "
+			"%d, data truncated.", tif->tif_name, llen, nsamples);
+		nsamples -= nsamples % llen;
+	}
+
+	for (i = 0; i < nsamples; i += llen, up += llen) {
+		switch (sp->user_datafmt)  {
+		case PIXARLOGDATAFMT_FLOAT:
+			horizontalAccumulateF(up, llen, sp->stride,
+					(float *)op, sp->ToLinearF);
+			op += llen * sizeof(float);
+			break;
+		case PIXARLOGDATAFMT_16BIT:
+			horizontalAccumulate16(up, llen, sp->stride,
+					(uint16 *)op, sp->ToLinear16);
+			op += llen * sizeof(uint16);
+			break;
+		case PIXARLOGDATAFMT_12BITPICIO:
+			horizontalAccumulate12(up, llen, sp->stride,
+					(int16 *)op, sp->ToLinearF);
+			op += llen * sizeof(int16);
+			break;
+		case PIXARLOGDATAFMT_11BITLOG:
+			horizontalAccumulate11(up, llen, sp->stride,
+					(uint16 *)op);
+			op += llen * sizeof(uint16);
+			break;
+		case PIXARLOGDATAFMT_8BIT:
+			horizontalAccumulate8(up, llen, sp->stride,
+					(unsigned char *)op, sp->ToLinear8);
+			op += llen * sizeof(unsigned char);
+			break;
+		case PIXARLOGDATAFMT_8BITABGR:
+			horizontalAccumulate8abgr(up, llen, sp->stride,
+					(unsigned char *)op, sp->ToLinear8);
+			op += llen * sizeof(unsigned char);
+			break;
+		default:
+			TIFFErrorExt(tif->tif_clientdata, tif->tif_name,
+				  "PixarLogDecode: unsupported bits/sample: %d", 
+				  td->td_bitspersample);
+			return (0);
+		}
+	}
+
+	return (1);
+}
+
+static int
+PixarLogSetupEncode(TIFF* tif)
+{
+	TIFFDirectory *td = &tif->tif_dir;
+	PixarLogState* sp = EncoderState(tif);
+	tsize_t tbuf_size;
+	static const char module[] = "PixarLogSetupEncode";
+
+	assert(sp != NULL);
+
+	/* for some reason, we can't do this in TIFFInitPixarLog */
+
+	sp->stride = (td->td_planarconfig == PLANARCONFIG_CONTIG ?
+	    td->td_samplesperpixel : 1);
+	tbuf_size = multiply(multiply(multiply(sp->stride, td->td_imagewidth),
+				      td->td_rowsperstrip), sizeof(uint16));
+	if (tbuf_size == 0)
+		return (0);
+	sp->tbuf = (uint16 *) _TIFFmalloc(tbuf_size);
+	if (sp->tbuf == NULL)
+		return (0);
+	if (sp->user_datafmt == PIXARLOGDATAFMT_UNKNOWN)
+		sp->user_datafmt = PixarLogGuessDataFmt(td);
+	if (sp->user_datafmt == PIXARLOGDATAFMT_UNKNOWN) {
+		TIFFErrorExt(tif->tif_clientdata, module, "PixarLog compression can't handle %d bit linear encodings", td->td_bitspersample);
+		return (0);
+	}
+
+	if (deflateInit(&sp->stream, sp->quality) != Z_OK) {
+		TIFFErrorExt(tif->tif_clientdata, module, "%s: %s", tif->tif_name, sp->stream.msg);
+		return (0);
+	} else {
+		sp->state |= PLSTATE_INIT;
+		return (1);
+	}
+}
+
+/*
+ * Reset encoding state at the start of a strip.
+ */
+static int
+PixarLogPreEncode(TIFF* tif, tsample_t s)
+{
+	PixarLogState *sp = EncoderState(tif);
+
+	(void) s;
+	assert(sp != NULL);
+	sp->stream.next_out = tif->tif_rawdata;
+	sp->stream.avail_out = tif->tif_rawdatasize;
+	return (deflateReset(&sp->stream) == Z_OK);
+}
+
+static void
+horizontalDifferenceF(float *ip, int n, int stride, uint16 *wp, uint16 *FromLT2)
+{
+
+    int32 r1, g1, b1, a1, r2, g2, b2, a2, mask;
+    float fltsize = Fltsize;
+
+#define  CLAMP(v) ( (v<(float)0.)   ? 0				\
+		  : (v<(float)2.)   ? FromLT2[(int)(v*fltsize)]	\
+		  : (v>(float)24.2) ? 2047			\
+		  : LogK1*log(v*LogK2) + 0.5 )
+
+    mask = CODE_MASK;
+    if (n >= stride) {
+	if (stride == 3) {
+	    r2 = wp[0] = (uint16) CLAMP(ip[0]);
+	    g2 = wp[1] = (uint16) CLAMP(ip[1]);
+	    b2 = wp[2] = (uint16) CLAMP(ip[2]);
+	    n -= 3;
+	    while (n > 0) {
+		n -= 3;
+		wp += 3;
+		ip += 3;
+		r1 = (int32) CLAMP(ip[0]); wp[0] = (r1-r2) & mask; r2 = r1;
+		g1 = (int32) CLAMP(ip[1]); wp[1] = (g1-g2) & mask; g2 = g1;
+		b1 = (int32) CLAMP(ip[2]); wp[2] = (b1-b2) & mask; b2 = b1;
+	    }
+	} else if (stride == 4) {
+	    r2 = wp[0] = (uint16) CLAMP(ip[0]);
+	    g2 = wp[1] = (uint16) CLAMP(ip[1]);
+	    b2 = wp[2] = (uint16) CLAMP(ip[2]);
+	    a2 = wp[3] = (uint16) CLAMP(ip[3]);
+	    n -= 4;
+	    while (n > 0) {
+		n -= 4;
+		wp += 4;
+		ip += 4;
+		r1 = (int32) CLAMP(ip[0]); wp[0] = (r1-r2) & mask; r2 = r1;
+		g1 = (int32) CLAMP(ip[1]); wp[1] = (g1-g2) & mask; g2 = g1;
+		b1 = (int32) CLAMP(ip[2]); wp[2] = (b1-b2) & mask; b2 = b1;
+		a1 = (int32) CLAMP(ip[3]); wp[3] = (a1-a2) & mask; a2 = a1;
+	    }
+	} else {
+	    ip += n - 1;	/* point to last one */
+	    wp += n - 1;	/* point to last one */
+	    n -= stride;
+	    while (n > 0) {
+		REPEAT(stride, wp[0] = (uint16) CLAMP(ip[0]);
+				wp[stride] -= wp[0];
+				wp[stride] &= mask;
+				wp--; ip--)
+		n -= stride;
+	    }
+	    REPEAT(stride, wp[0] = (uint16) CLAMP(ip[0]); wp--; ip--)
+	}
+    }
+}
+
+static void
+horizontalDifference16(unsigned short *ip, int n, int stride, 
+	unsigned short *wp, uint16 *From14)
+{
+    register int  r1, g1, b1, a1, r2, g2, b2, a2, mask;
+
+/* assumption is unsigned pixel values */
+#undef   CLAMP
+#define  CLAMP(v) From14[(v) >> 2]
+
+    mask = CODE_MASK;
+    if (n >= stride) {
+	if (stride == 3) {
+	    r2 = wp[0] = CLAMP(ip[0]);  g2 = wp[1] = CLAMP(ip[1]);
+	    b2 = wp[2] = CLAMP(ip[2]);
+	    n -= 3;
+	    while (n > 0) {
+		n -= 3;
+		wp += 3;
+		ip += 3;
+		r1 = CLAMP(ip[0]); wp[0] = (r1-r2) & mask; r2 = r1;
+		g1 = CLAMP(ip[1]); wp[1] = (g1-g2) & mask; g2 = g1;
+		b1 = CLAMP(ip[2]); wp[2] = (b1-b2) & mask; b2 = b1;
+	    }
+	} else if (stride == 4) {
+	    r2 = wp[0] = CLAMP(ip[0]);  g2 = wp[1] = CLAMP(ip[1]);
+	    b2 = wp[2] = CLAMP(ip[2]);  a2 = wp[3] = CLAMP(ip[3]);
+	    n -= 4;
+	    while (n > 0) {
+		n -= 4;
+		wp += 4;
+		ip += 4;
+		r1 = CLAMP(ip[0]); wp[0] = (r1-r2) & mask; r2 = r1;
+		g1 = CLAMP(ip[1]); wp[1] = (g1-g2) & mask; g2 = g1;
+		b1 = CLAMP(ip[2]); wp[2] = (b1-b2) & mask; b2 = b1;
+		a1 = CLAMP(ip[3]); wp[3] = (a1-a2) & mask; a2 = a1;
+	    }
+	} else {
+	    ip += n - 1;	/* point to last one */
+	    wp += n - 1;	/* point to last one */
+	    n -= stride;
+	    while (n > 0) {
+		REPEAT(stride, wp[0] = CLAMP(ip[0]);
+				wp[stride] -= wp[0];
+				wp[stride] &= mask;
+				wp--; ip--)
+		n -= stride;
+	    }
+	    REPEAT(stride, wp[0] = CLAMP(ip[0]); wp--; ip--)
+	}
+    }
+}
+
+
+static void
+horizontalDifference8(unsigned char *ip, int n, int stride, 
+	unsigned short *wp, uint16 *From8)
+{
+    register int  r1, g1, b1, a1, r2, g2, b2, a2, mask;
+
+#undef	 CLAMP
+#define  CLAMP(v) (From8[(v)])
+
+    mask = CODE_MASK;
+    if (n >= stride) {
+	if (stride == 3) {
+	    r2 = wp[0] = CLAMP(ip[0]);  g2 = wp[1] = CLAMP(ip[1]);
+	    b2 = wp[2] = CLAMP(ip[2]);
+	    n -= 3;
+	    while (n > 0) {
+		n -= 3;
+		r1 = CLAMP(ip[3]); wp[3] = (r1-r2) & mask; r2 = r1;
+		g1 = CLAMP(ip[4]); wp[4] = (g1-g2) & mask; g2 = g1;
+		b1 = CLAMP(ip[5]); wp[5] = (b1-b2) & mask; b2 = b1;
+		wp += 3;
+		ip += 3;
+	    }
+	} else if (stride == 4) {
+	    r2 = wp[0] = CLAMP(ip[0]);  g2 = wp[1] = CLAMP(ip[1]);
+	    b2 = wp[2] = CLAMP(ip[2]);  a2 = wp[3] = CLAMP(ip[3]);
+	    n -= 4;
+	    while (n > 0) {
+		n -= 4;
+		r1 = CLAMP(ip[4]); wp[4] = (r1-r2) & mask; r2 = r1;
+		g1 = CLAMP(ip[5]); wp[5] = (g1-g2) & mask; g2 = g1;
+		b1 = CLAMP(ip[6]); wp[6] = (b1-b2) & mask; b2 = b1;
+		a1 = CLAMP(ip[7]); wp[7] = (a1-a2) & mask; a2 = a1;
+		wp += 4;
+		ip += 4;
+	    }
+	} else {
+	    wp += n + stride - 1;	/* point to last one */
+	    ip += n + stride - 1;	/* point to last one */
+	    n -= stride;
+	    while (n > 0) {
+		REPEAT(stride, wp[0] = CLAMP(ip[0]);
+				wp[stride] -= wp[0];
+				wp[stride] &= mask;
+				wp--; ip--)
+		n -= stride;
+	    }
+	    REPEAT(stride, wp[0] = CLAMP(ip[0]); wp--; ip--)
+	}
+    }
+}
+
+/*
+ * Encode a chunk of pixels.
+ */
+static int
+PixarLogEncode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
+{
+	TIFFDirectory *td = &tif->tif_dir;
+	PixarLogState *sp = EncoderState(tif);
+	static const char module[] = "PixarLogEncode";
+	int	i, n, llen;
+	unsigned short * up;
+
+	(void) s;
+
+	switch (sp->user_datafmt) {
+	case PIXARLOGDATAFMT_FLOAT:
+		n = cc / sizeof(float);		/* XXX float == 32 bits */
+		break;
+	case PIXARLOGDATAFMT_16BIT:
+	case PIXARLOGDATAFMT_12BITPICIO:
+	case PIXARLOGDATAFMT_11BITLOG:
+		n = cc / sizeof(uint16);	/* XXX uint16 == 16 bits */
+		break;
+	case PIXARLOGDATAFMT_8BIT:
+	case PIXARLOGDATAFMT_8BITABGR:
+		n = cc;
+		break;
+	default:
+		TIFFErrorExt(tif->tif_clientdata, tif->tif_name,
+			"%d bit input not supported in PixarLog",
+			td->td_bitspersample);
+		return 0;
+	}
+
+	llen = sp->stride * td->td_imagewidth;
+
+	for (i = 0, up = sp->tbuf; i < n; i += llen, up += llen) {
+		switch (sp->user_datafmt)  {
+		case PIXARLOGDATAFMT_FLOAT:
+			horizontalDifferenceF((float *)bp, llen, 
+				sp->stride, up, sp->FromLT2);
+			bp += llen * sizeof(float);
+			break;
+		case PIXARLOGDATAFMT_16BIT:
+			horizontalDifference16((uint16 *)bp, llen, 
+				sp->stride, up, sp->From14);
+			bp += llen * sizeof(uint16);
+			break;
+		case PIXARLOGDATAFMT_8BIT:
+			horizontalDifference8((unsigned char *)bp, llen, 
+				sp->stride, up, sp->From8);
+			bp += llen * sizeof(unsigned char);
+			break;
+		default:
+			TIFFErrorExt(tif->tif_clientdata, tif->tif_name,
+				"%d bit input not supported in PixarLog",
+				td->td_bitspersample);
+			return 0;
+		}
+	}
+ 
+	sp->stream.next_in = (unsigned char *) sp->tbuf;
+	sp->stream.avail_in = n * sizeof(uint16);
+
+	do {
+		if (deflate(&sp->stream, Z_NO_FLUSH) != Z_OK) {
+			TIFFErrorExt(tif->tif_clientdata, module, "%s: Encoder error: %s",
+			    tif->tif_name, sp->stream.msg);
+			return (0);
+		}
+		if (sp->stream.avail_out == 0) {
+			tif->tif_rawcc = tif->tif_rawdatasize;
+			TIFFFlushData1(tif);
+			sp->stream.next_out = tif->tif_rawdata;
+			sp->stream.avail_out = tif->tif_rawdatasize;
+		}
+	} while (sp->stream.avail_in > 0);
+	return (1);
+}
+
+/*
+ * Finish off an encoded strip by flushing the last
+ * string and tacking on an End Of Information code.
+ */
+
+static int
+PixarLogPostEncode(TIFF* tif)
+{
+	PixarLogState *sp = EncoderState(tif);
+	static const char module[] = "PixarLogPostEncode";
+	int state;
+
+	sp->stream.avail_in = 0;
+
+	do {
+		state = deflate(&sp->stream, Z_FINISH);
+		switch (state) {
+		case Z_STREAM_END:
+		case Z_OK:
+		    if (sp->stream.avail_out != (uint32)tif->tif_rawdatasize) {
+			    tif->tif_rawcc =
+				tif->tif_rawdatasize - sp->stream.avail_out;
+			    TIFFFlushData1(tif);
+			    sp->stream.next_out = tif->tif_rawdata;
+			    sp->stream.avail_out = tif->tif_rawdatasize;
+		    }
+		    break;
+		default:
+			TIFFErrorExt(tif->tif_clientdata, module, "%s: zlib error: %s",
+			tif->tif_name, sp->stream.msg);
+		    return (0);
+		}
+	} while (state != Z_STREAM_END);
+	return (1);
+}
+
+static void
+PixarLogClose(TIFF* tif)
+{
+	TIFFDirectory *td = &tif->tif_dir;
+
+	/* In a really sneaky maneuver, on close, we covertly modify both
+	 * bitspersample and sampleformat in the directory to indicate
+	 * 8-bit linear.  This way, the decode "just works" even for
+	 * readers that don't know about PixarLog, or how to set
+	 * the PIXARLOGDATFMT pseudo-tag.
+	 */
+	td->td_bitspersample = 8;
+	td->td_sampleformat = SAMPLEFORMAT_UINT;
+}
+
+static void
+PixarLogCleanup(TIFF* tif)
+{
+	PixarLogState* sp = (PixarLogState*) tif->tif_data;
+
+	assert(sp != 0);
+
+	(void)TIFFPredictorCleanup(tif);
+
+	tif->tif_tagmethods.vgetfield = sp->vgetparent;
+	tif->tif_tagmethods.vsetfield = sp->vsetparent;
+
+	if (sp->FromLT2) _TIFFfree(sp->FromLT2);
+	if (sp->From14) _TIFFfree(sp->From14);
+	if (sp->From8) _TIFFfree(sp->From8);
+	if (sp->ToLinearF) _TIFFfree(sp->ToLinearF);
+	if (sp->ToLinear16) _TIFFfree(sp->ToLinear16);
+	if (sp->ToLinear8) _TIFFfree(sp->ToLinear8);
+	if (sp->state&PLSTATE_INIT) {
+		if (tif->tif_mode == O_RDONLY)
+			inflateEnd(&sp->stream);
+		else
+			deflateEnd(&sp->stream);
+	}
+	if (sp->tbuf)
+		_TIFFfree(sp->tbuf);
+	_TIFFfree(sp);
+	tif->tif_data = NULL;
+
+	_TIFFSetDefaultCompressionState(tif);
+}
+
+static int
+PixarLogVSetField(TIFF* tif, ttag_t tag, va_list ap)
+{
+    PixarLogState *sp = (PixarLogState *)tif->tif_data;
+    int result;
+    static const char module[] = "PixarLogVSetField";
+
+    switch (tag) {
+     case TIFFTAG_PIXARLOGQUALITY:
+		sp->quality = va_arg(ap, int);
+		if (tif->tif_mode != O_RDONLY && (sp->state&PLSTATE_INIT)) {
+			if (deflateParams(&sp->stream,
+			    sp->quality, Z_DEFAULT_STRATEGY) != Z_OK) {
+				TIFFErrorExt(tif->tif_clientdata, module, "%s: zlib error: %s",
+					tif->tif_name, sp->stream.msg);
+				return (0);
+			}
+		}
+		return (1);
+     case TIFFTAG_PIXARLOGDATAFMT:
+	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 PIXARLOGDATAFMT_8BIT:
+	 case PIXARLOGDATAFMT_8BITABGR:
+	    TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, 8);
+	    TIFFSetField(tif, TIFFTAG_SAMPLEFORMAT, SAMPLEFORMAT_UINT);
+	    break;
+	 case PIXARLOGDATAFMT_11BITLOG:
+	    TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, 16);
+	    TIFFSetField(tif, TIFFTAG_SAMPLEFORMAT, SAMPLEFORMAT_UINT);
+	    break;
+	 case PIXARLOGDATAFMT_12BITPICIO:
+	    TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, 16);
+	    TIFFSetField(tif, TIFFTAG_SAMPLEFORMAT, SAMPLEFORMAT_INT);
+	    break;
+	 case PIXARLOGDATAFMT_16BIT:
+	    TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, 16);
+	    TIFFSetField(tif, TIFFTAG_SAMPLEFORMAT, SAMPLEFORMAT_UINT);
+	    break;
+	 case PIXARLOGDATAFMT_FLOAT:
+	    TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, 32);
+	    TIFFSetField(tif, TIFFTAG_SAMPLEFORMAT, SAMPLEFORMAT_IEEEFP);
+	    break;
+	}
+	/*
+	 * Must recalculate sizes should bits/sample change.
+	 */
+	tif->tif_tilesize = isTiled(tif) ? TIFFTileSize(tif) : (tsize_t) -1;
+	tif->tif_scanlinesize = TIFFScanlineSize(tif);
+	result = 1;		/* NB: pseudo tag */
+	break;
+     default:
+	result = (*sp->vsetparent)(tif, tag, ap);
+    }
+    return (result);
+}
+
+static int
+PixarLogVGetField(TIFF* tif, ttag_t tag, va_list ap)
+{
+    PixarLogState *sp = (PixarLogState *)tif->tif_data;
+
+    switch (tag) {
+     case TIFFTAG_PIXARLOGQUALITY:
+	*va_arg(ap, int*) = sp->quality;
+	break;
+     case TIFFTAG_PIXARLOGDATAFMT:
+	*va_arg(ap, int*) = sp->user_datafmt;
+	break;
+     default:
+	return (*sp->vgetparent)(tif, tag, ap);
+    }
+    return (1);
+}
+
+static const TIFFFieldInfo pixarlogFieldInfo[] = {
+    {TIFFTAG_PIXARLOGDATAFMT,0,0,TIFF_ANY,  FIELD_PSEUDO,FALSE,FALSE,""},
+    {TIFFTAG_PIXARLOGQUALITY,0,0,TIFF_ANY,  FIELD_PSEUDO,FALSE,FALSE,""}
+};
+
+int
+TIFFInitPixarLog(TIFF* tif, int scheme)
+{
+	static const char module[] = "TIFFInitPixarLog";
+
+	PixarLogState* sp;
+
+	assert(scheme == COMPRESSION_PIXARLOG);
+
+	/*
+	 * Merge codec-specific tag information.
+	 */
+	if (!_TIFFMergeFieldInfo(tif, pixarlogFieldInfo,
+				 TIFFArrayCount(pixarlogFieldInfo))) {
+		TIFFErrorExt(tif->tif_clientdata, module,
+			     "Merging PixarLog codec-specific tags failed");
+		return 0;
+	}
+
+	/*
+	 * Allocate state block so tag methods have storage to record values.
+	 */
+	tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (PixarLogState));
+	if (tif->tif_data == NULL)
+		goto bad;
+	sp = (PixarLogState*) tif->tif_data;
+	_TIFFmemset(sp, 0, sizeof (*sp));
+	sp->stream.data_type = Z_BINARY;
+	sp->user_datafmt = PIXARLOGDATAFMT_UNKNOWN;
+
+	/*
+	 * Install codec methods.
+	 */
+	tif->tif_setupdecode = PixarLogSetupDecode;
+	tif->tif_predecode = PixarLogPreDecode;
+	tif->tif_decoderow = PixarLogDecode;
+	tif->tif_decodestrip = PixarLogDecode;
+	tif->tif_decodetile = PixarLogDecode;
+	tif->tif_setupencode = PixarLogSetupEncode;
+	tif->tif_preencode = PixarLogPreEncode;
+	tif->tif_postencode = PixarLogPostEncode;
+	tif->tif_encoderow = PixarLogEncode;
+	tif->tif_encodestrip = PixarLogEncode;
+	tif->tif_encodetile = PixarLogEncode;
+	tif->tif_close = PixarLogClose;
+	tif->tif_cleanup = PixarLogCleanup;
+
+	/* Override SetField so we can handle our private pseudo-tag */
+	sp->vgetparent = tif->tif_tagmethods.vgetfield;
+	tif->tif_tagmethods.vgetfield = PixarLogVGetField;   /* hook for codec tags */
+	sp->vsetparent = tif->tif_tagmethods.vsetfield;
+	tif->tif_tagmethods.vsetfield = PixarLogVSetField;   /* hook for codec tags */
+
+	/* Default values for codec-specific fields */
+	sp->quality = Z_DEFAULT_COMPRESSION; /* default comp. level */
+	sp->state = 0;
+
+	/* we don't wish to use the predictor, 
+	 * the default is none, which predictor value 1
+	 */
+	(void) TIFFPredictorInit(tif);
+
+	/*
+	 * build the companding tables 
+	 */
+	PixarLogMakeTables(sp);
+
+	return (1);
+bad:
+	TIFFErrorExt(tif->tif_clientdata, module,
+		     "No space for PixarLog state block");
+	return (0);
+}
+#endif /* PIXARLOG_SUPPORT */
+
+/* vim: set ts=8 sts=8 sw=8 noet: */
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 8
+ * fill-column: 78
+ * End:
+ */