Adding qcms to use for handling ICC tagged images.

third_party/qcms/iccread.c

Index: third_party/qcms/iccread.c
diff --git a/third_party/qcms/iccread.c b/third_party/qcms/iccread.c
new file mode 100644
index 0000000000000000000000000000000000000000..36b701179a91d41d1be5fb6dd7b7215bb88d7f3e
--- /dev/null
+++ b/third_party/qcms/iccread.c
@@ -0,0 +1,1204 @@
+/* vim: set ts=8 sw=8 noexpandtab: */
+//  qcms
+//  Copyright (C) 2009 Mozilla Foundation
+//  Copyright (C) 1998-2007 Marti Maria
+//
+// Permission is hereby granted, free of charge, to any person obtaining 
+// a copy of this software and associated documentation files (the "Software"), 
+// to deal in the Software without restriction, including without limitation 
+// the rights to use, copy, modify, merge, publish, distribute, sublicense, 
+// and/or sell copies of the Software, and to permit persons to whom the Software 
+// is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in 
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO 
+// THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+#include <math.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h> //memset
+#include "qcmsint.h"
+
+/* It might be worth having a unified limit on content controlled
+ * allocation per profile. This would remove the need for many
+ * of the arbitrary limits that we used */
+
+typedef uint32_t be32;
+typedef uint16_t be16;
+
+#if 0
+not used yet
+/* __builtin_bswap isn't available in older gccs
+ * so open code it for now */
+static be32 cpu_to_be32(int32_t v)
+{
+#ifdef IS_LITTLE_ENDIAN
+	return ((v & 0xff) << 24) | ((v & 0xff00) << 8) | ((v & 0xff0000) >> 8) | ((v & 0xff000000) >> 24);
+	//return __builtin_bswap32(v);
+	return v;
+#endif
+}
+#endif
+
+static uint32_t be32_to_cpu(be32 v)
+{
+#ifdef IS_LITTLE_ENDIAN
+	return ((v & 0xff) << 24) | ((v & 0xff00) << 8) | ((v & 0xff0000) >> 8) | ((v & 0xff000000) >> 24);
+	//return __builtin_bswap32(v);
+#else
+	return v;
+#endif
+}
+
+static uint16_t be16_to_cpu(be16 v)
+{
+#ifdef IS_LITTLE_ENDIAN
+	return ((v & 0xff) << 8) | ((v & 0xff00) >> 8);
+#else
+	return v;
+#endif
+}
+
+/* a wrapper around the memory that we are going to parse
+ * into a qcms_profile */
+struct mem_source
+{
+	const unsigned char *buf;
+	size_t size;
+	qcms_bool valid;
+	const char *invalid_reason;
+};
+
+static void invalid_source(struct mem_source *mem, const char *reason)
+{
+	mem->valid = false;
+	mem->invalid_reason = reason;
+}
+
+static uint32_t read_u32(struct mem_source *mem, size_t offset)
+{
+	/* Subtract from mem->size instead of the more intuitive adding to offset.
+	 * This avoids overflowing offset. The subtraction is safe because
+	 * mem->size is guaranteed to be > 4 */
+	if (offset > mem->size - 4) {
+		invalid_source(mem, "Invalid offset");
+		return 0;
+	} else {
+		be32 k;
+		memcpy(&k, mem->buf + offset, sizeof(k));
+		return be32_to_cpu(k);
+	}
+}
+
+static uint16_t read_u16(struct mem_source *mem, size_t offset)
+{
+	if (offset > mem->size - 2) {
+		invalid_source(mem, "Invalid offset");
+		return 0;
+	} else {
+		be16 k;
+		memcpy(&k, mem->buf + offset, sizeof(k));
+		return be16_to_cpu(k);
+	}
+}
+
+static uint8_t read_u8(struct mem_source *mem, size_t offset)
+{
+	if (offset > mem->size - 1) {
+		invalid_source(mem, "Invalid offset");
+		return 0;
+	} else {
+		return *(uint8_t*)(mem->buf + offset);
+	}
+}
+
+static s15Fixed16Number read_s15Fixed16Number(struct mem_source *mem, size_t offset)
+{
+	return read_u32(mem, offset);
+}
+
+static uInt8Number read_uInt8Number(struct mem_source *mem, size_t offset)
+{
+	return read_u8(mem, offset);
+}
+
+static uInt16Number read_uInt16Number(struct mem_source *mem, size_t offset)
+{
+	return read_u16(mem, offset);
+}
+
+#define BAD_VALUE_PROFILE NULL
+#define INVALID_PROFILE NULL
+#define NO_MEM_PROFILE NULL
+
+/* An arbitrary 4MB limit on profile size */
+#define MAX_PROFILE_SIZE 1024*1024*4
+#define MAX_TAG_COUNT 1024
+
+static void check_CMM_type_signature(struct mem_source *src)
+{
+	//uint32_t CMM_type_signature = read_u32(src, 4);
+	//TODO: do the check?
+
+}
+
+static void check_profile_version(struct mem_source *src)
+{
+
+	/*
+	uint8_t major_revision = read_u8(src, 8 + 0);
+	uint8_t minor_revision = read_u8(src, 8 + 1);
+	*/
+	uint8_t reserved1      = read_u8(src, 8 + 2);
+	uint8_t reserved2      = read_u8(src, 8 + 3);
+	/* Checking the version doesn't buy us anything
+	if (major_revision != 0x4) {
+		if (major_revision > 0x2)
+			invalid_source(src, "Unsupported major revision");
+		if (minor_revision > 0x40)
+			invalid_source(src, "Unsupported minor revision");
+	}
+	*/
+	if (reserved1 != 0 || reserved2 != 0)
+		invalid_source(src, "Invalid reserved bytes");
+}
+
+#define INPUT_DEVICE_PROFILE   0x73636e72 // 'scnr'
+#define DISPLAY_DEVICE_PROFILE 0x6d6e7472 // 'mntr'
+#define OUTPUT_DEVICE_PROFILE  0x70727472 // 'prtr'
+#define DEVICE_LINK_PROFILE    0x6c696e6b // 'link'
+#define COLOR_SPACE_PROFILE    0x73706163 // 'spac'
+#define ABSTRACT_PROFILE       0x61627374 // 'abst'
+#define NAMED_COLOR_PROFILE    0x6e6d636c // 'nmcl'
+
+static void read_class_signature(qcms_profile *profile, struct mem_source *mem)
+{
+	profile->class = read_u32(mem, 12);
+	switch (profile->class) {
+		case DISPLAY_DEVICE_PROFILE:
+		case INPUT_DEVICE_PROFILE:
+		case OUTPUT_DEVICE_PROFILE:
+		case COLOR_SPACE_PROFILE:
+			break;
+		default:
+			invalid_source(mem, "Invalid  Profile/Device Class signature");
+	}
+}
+
+static void read_color_space(qcms_profile *profile, struct mem_source *mem)
+{
+	profile->color_space = read_u32(mem, 16);
+	switch (profile->color_space) {
+		case RGB_SIGNATURE:
+		case GRAY_SIGNATURE:
+			break;
+		default:
+			invalid_source(mem, "Unsupported colorspace");
+	}
+}
+
+static void read_pcs(qcms_profile *profile, struct mem_source *mem)
+{
+	profile->pcs = read_u32(mem, 20);
+	switch (profile->pcs) {
+		case XYZ_SIGNATURE:
+		case LAB_SIGNATURE:
+			break;
+		default:
+			invalid_source(mem, "Unsupported pcs");
+	}
+}
+
+struct tag
+{
+	uint32_t signature;
+	uint32_t offset;
+	uint32_t size;
+};
+
+struct tag_index {
+	uint32_t count;
+	struct tag *tags;
+};
+
+static struct tag_index read_tag_table(qcms_profile *profile, struct mem_source *mem)
+{
+	struct tag_index index = {0, NULL};
+	unsigned int i;
+
+	index.count = read_u32(mem, 128);
+	if (index.count > MAX_TAG_COUNT) {
+		invalid_source(mem, "max number of tags exceeded");
+		return index;
+	}
+
+	index.tags = malloc(sizeof(struct tag)*index.count);
+	if (index.tags) {
+		for (i = 0; i < index.count; i++) {
+			index.tags[i].signature = read_u32(mem, 128 + 4 + 4*i*3);
+			index.tags[i].offset    = read_u32(mem, 128 + 4 + 4*i*3 + 4);
+			index.tags[i].size      = read_u32(mem, 128 + 4 + 4*i*3 + 8);
+		}
+	}
+
+	return index;
+}
+
+// Checks a profile for obvious inconsistencies and returns
+// true if the profile looks bogus and should probably be
+// ignored.
+qcms_bool qcms_profile_is_bogus(qcms_profile *profile)
+{
+       float sum[3], target[3], tolerance[3];
+       float rX, rY, rZ, gX, gY, gZ, bX, bY, bZ;
+       bool negative;
+       unsigned i;
+
+       // We currently only check the bogosity of RGB profiles
+       if (profile->color_space != RGB_SIGNATURE)
+	       return false;
+
+       if (profile->A2B0 || profile->B2A0)
+               return false;
+
+       rX = s15Fixed16Number_to_float(profile->redColorant.X);
+       rY = s15Fixed16Number_to_float(profile->redColorant.Y);
+       rZ = s15Fixed16Number_to_float(profile->redColorant.Z);
+
+       gX = s15Fixed16Number_to_float(profile->greenColorant.X);
+       gY = s15Fixed16Number_to_float(profile->greenColorant.Y);
+       gZ = s15Fixed16Number_to_float(profile->greenColorant.Z);
+
+       bX = s15Fixed16Number_to_float(profile->blueColorant.X);
+       bY = s15Fixed16Number_to_float(profile->blueColorant.Y);
+       bZ = s15Fixed16Number_to_float(profile->blueColorant.Z);
+
+       // Check if any of the XYZ values are negative (see mozilla bug 498245)
+       // CIEXYZ tristimulus values cannot be negative according to the spec.
+       negative =
+	       (rX < 0) || (rY < 0) || (rZ < 0) ||
+	       (gX < 0) || (gY < 0) || (gZ < 0) ||
+	       (bX < 0) || (bY < 0) || (bZ < 0);
+
+       if (negative)
+	       return true;
+
+
+       // Sum the values; they should add up to something close to white
+       sum[0] = rX + gX + bX;
+       sum[1] = rY + gY + bY;
+       sum[2] = rZ + gZ + bZ;
+
+       // Build our target vector (see mozilla bug 460629)
+       target[0] = 0.96420;
+       target[1] = 1.00000;
+       target[2] = 0.82491;
+
+       // Our tolerance vector - Recommended by Chris Murphy based on
+       // conversion from the LAB space criterion of no more than 3 in any one
+       // channel. This is similar to, but slightly more tolerant than Adobe's
+       // criterion.
+       tolerance[0] = 0.02;
+       tolerance[1] = 0.02;
+       tolerance[2] = 0.04;
+
+       // Compare with our tolerance
+       for (i = 0; i < 3; ++i) {
+           if (!(((sum[i] - tolerance[i]) <= target[i]) &&
+                 ((sum[i] + tolerance[i]) >= target[i])))
+               return true;
+       }
+
+       // All Good
+       return false;
+}
+
+#define TAG_bXYZ 0x6258595a
+#define TAG_gXYZ 0x6758595a
+#define TAG_rXYZ 0x7258595a
+#define TAG_rTRC 0x72545243
+#define TAG_bTRC 0x62545243
+#define TAG_gTRC 0x67545243
+#define TAG_kTRC 0x6b545243
+#define TAG_A2B0 0x41324230
+#define TAG_B2A0 0x42324130
+#define TAG_CHAD 0x63686164
+
+static struct tag *find_tag(struct tag_index index, uint32_t tag_id)
+{
+	unsigned int i;
+	struct tag *tag = NULL;
+	for (i = 0; i < index.count; i++) {
+		if (index.tags[i].signature == tag_id) {
+			return &index.tags[i];
+		}
+	}
+	return tag;
+}
+
+#define XYZ_TYPE		0x58595a20 // 'XYZ '
+#define CURVE_TYPE		0x63757276 // 'curv'
+#define PARAMETRIC_CURVE_TYPE	0x70617261 // 'para'
+#define LUT16_TYPE		0x6d667432 // 'mft2'
+#define LUT8_TYPE		0x6d667431 // 'mft1'
+#define LUT_MAB_TYPE		0x6d414220 // 'mAB '
+#define LUT_MBA_TYPE		0x6d424120 // 'mBA '
+#define CHROMATIC_TYPE		0x73663332 // 'sf32'
+
+static struct matrix read_tag_s15Fixed16ArrayType(struct mem_source *src, struct tag_index index, uint32_t tag_id)
+{
+	struct tag *tag = find_tag(index, tag_id);
+	struct matrix matrix;
+	if (tag) {
+		uint8_t i;
+		uint32_t offset = tag->offset;
+		uint32_t type = read_u32(src, offset);
+
+		// Check mandatory type signature for s16Fixed16ArrayType
+		if (type != CHROMATIC_TYPE) {
+			invalid_source(src, "unexpected type, expected 'sf32'");
+		}
+
+		for (i = 0; i < 9; i++) {
+			matrix.m[i/3][i%3] = s15Fixed16Number_to_float(read_s15Fixed16Number(src, offset+8+i*4));
+		}
+		matrix.invalid = false;
+	} else {
+		matrix.invalid = true;
+		invalid_source(src, "missing sf32tag");
+	}
+	return matrix;
+}
+
+static struct XYZNumber read_tag_XYZType(struct mem_source *src, struct tag_index index, uint32_t tag_id)
+{
+	struct XYZNumber num = {0, 0, 0};
+	struct tag *tag = find_tag(index, tag_id);
+	if (tag) {
+		uint32_t offset = tag->offset;
+
+		uint32_t type = read_u32(src, offset);
+		if (type != XYZ_TYPE)
+			invalid_source(src, "unexpected type, expected XYZ");
+		num.X = read_s15Fixed16Number(src, offset+8);
+		num.Y = read_s15Fixed16Number(src, offset+12);
+		num.Z = read_s15Fixed16Number(src, offset+16);
+	} else {
+		invalid_source(src, "missing xyztag");
+	}
+	return num;
+}
+
+// Read the tag at a given offset rather then the tag_index. 
+// This method is used when reading mAB tags where nested curveType are
+// present that are not part of the tag_index.
+static struct curveType *read_curveType(struct mem_source *src, uint32_t offset, uint32_t *len)
+{
+	static const size_t COUNT_TO_LENGTH[5] = {1, 3, 4, 5, 7};
+	struct curveType *curve = NULL;
+	uint32_t type = read_u32(src, offset);
+	uint32_t count;
+	int i;
+
+	if (type != CURVE_TYPE && type != PARAMETRIC_CURVE_TYPE) {
+		invalid_source(src, "unexpected type, expected CURV or PARA");
+		return NULL;
+	}
+
+	if (type == CURVE_TYPE) {
+		count = read_u32(src, offset+8);
+
+#define MAX_CURVE_ENTRIES 40000 //arbitrary
+		if (count > MAX_CURVE_ENTRIES) {
+			invalid_source(src, "curve size too large");
+			return NULL;
+		}
+		curve = malloc(sizeof(struct curveType) + sizeof(uInt16Number)*count);
+		if (!curve)
+			return NULL;
+
+		curve->count = count;
+		curve->type = type;
+
+		for (i=0; i<count; i++) {
+			curve->data[i] = read_u16(src, offset + 12 + i*2);
+		}
+		*len = 12 + count * 2;
+	} else { //PARAMETRIC_CURVE_TYPE
+		count = read_u16(src, offset+8);
+
+		if (count > 4) {
+			invalid_source(src, "parametric function type not supported.");
+			return NULL;
+		}
+
+		curve = malloc(sizeof(struct curveType));
+		if (!curve)
+			return NULL;
+
+		curve->count = count;
+		curve->type = type;
+
+		for (i=0; i < COUNT_TO_LENGTH[count]; i++) {
+			curve->parameter[i] = s15Fixed16Number_to_float(read_s15Fixed16Number(src, offset + 12 + i*4));	
+		}
+		*len = 12 + COUNT_TO_LENGTH[count] * 4;
+
+		if ((count == 1 || count == 2)) {
+			/* we have a type 1 or type 2 function that has a division by 'a' */
+			float a = curve->parameter[1];
+			if (a == 0.f)
+				invalid_source(src, "parametricCurve definition causes division by zero.");
+		}
+	}
+
+	return curve;
+}
+
+static struct curveType *read_tag_curveType(struct mem_source *src, struct tag_index index, uint32_t tag_id)
+{
+	struct tag *tag = find_tag(index, tag_id);
+	struct curveType *curve = NULL;
+	if (tag) {
+		uint32_t len;
+		return read_curveType(src, tag->offset, &len);
+	} else {
+		invalid_source(src, "missing curvetag");
+	}
+
+	return curve;
+}
+
+#define MAX_CLUT_SIZE 500000 // arbitrary
+#define MAX_CHANNELS 10 // arbitrary
+static void read_nested_curveType(struct mem_source *src, struct curveType *(*curveArray)[MAX_CHANNELS], uint8_t num_channels, uint32_t curve_offset)
+{
+	uint32_t channel_offset = 0;
+	int i;
+	for (i = 0; i < num_channels; i++) {
+		uint32_t tag_len;
+
+		(*curveArray)[i] = read_curveType(src, curve_offset + channel_offset, &tag_len);
+		if (!(*curveArray)[i]) {
+			invalid_source(src, "invalid nested curveType curve");
+		}
+
+		channel_offset += tag_len;
+		// 4 byte aligned
+		if ((tag_len % 4) != 0)
+			channel_offset += 4 - (tag_len % 4);
+	}
+
+}
+
+static void mAB_release(struct lutmABType *lut)
+{
+	uint8_t i;
+
+	for (i = 0; i < lut->num_in_channels; i++){
+		free(lut->a_curves[i]);
+	}
+	for (i = 0; i < lut->num_out_channels; i++){
+		free(lut->b_curves[i]);
+		free(lut->m_curves[i]);
+	}
+	free(lut);
+}
+
+/* See section 10.10 for specs */
+static struct lutmABType *read_tag_lutmABType(struct mem_source *src, struct tag_index index, uint32_t tag_id)
+{
+	struct tag *tag = find_tag(index, tag_id);
+	uint32_t offset = tag->offset;
+	uint32_t a_curve_offset, b_curve_offset, m_curve_offset;
+	uint32_t matrix_offset;
+	uint32_t clut_offset;
+	uint32_t clut_size = 1;
+	uint8_t clut_precision;
+	uint32_t type = read_u32(src, offset);
+	uint8_t num_in_channels, num_out_channels;
+	struct lutmABType *lut;
+	int i;
+
+	if (type != LUT_MAB_TYPE && type != LUT_MBA_TYPE) {
+		return NULL;
+	}
+
+	num_in_channels = read_u8(src, offset + 8);
+	num_out_channels = read_u8(src, offset + 8);
+	if (num_in_channels > MAX_CHANNELS || num_out_channels > MAX_CHANNELS)
+		return NULL;
+
+	// We require 3in/out channels since we only support RGB->XYZ (or RGB->LAB)
+	// XXX: If we remove this restriction make sure that the number of channels
+	//      is less or equal to the maximum number of mAB curves in qcmsint.h
+	//      also check for clut_size overflow.
+	if (num_in_channels != 3 || num_out_channels != 3)
+		return NULL;
+
+	// some of this data is optional and is denoted by a zero offset
+	// we also use this to track their existance
+	a_curve_offset = read_u32(src, offset + 28);
+	clut_offset = read_u32(src, offset + 24);
+	m_curve_offset = read_u32(src, offset + 20);
+	matrix_offset = read_u32(src, offset + 16);
+	b_curve_offset = read_u32(src, offset + 12);
+
+	// Convert offsets relative to the tag to relative to the profile
+	// preserve zero for optional fields
+	if (a_curve_offset)
+		a_curve_offset += offset;
+	if (clut_offset)
+		clut_offset += offset;
+	if (m_curve_offset)
+		m_curve_offset += offset;
+	if (matrix_offset)
+		matrix_offset += offset;
+	if (b_curve_offset)
+		b_curve_offset += offset;
+
+	if (clut_offset) {
+		assert (num_in_channels == 3);
+		// clut_size can not overflow since lg(256^num_in_channels) = 24 bits.
+		for (i = 0; i < num_in_channels; i++) {
+			clut_size *= read_u8(src, clut_offset + i);
+		}
+	} else {
+		clut_size = 0;
+	}
+
+	// 24bits * 3 won't overflow either
+	clut_size = clut_size * num_out_channels;
+
+	if (clut_size > MAX_CLUT_SIZE)
+		return NULL;
+
+	lut = malloc(sizeof(struct lutmABType) + (clut_size) * sizeof(float));
+	if (!lut)
+		return NULL;
+	// we'll fill in the rest below
+	memset(lut, 0, sizeof(struct lutmABType));
+	lut->clut_table   = &lut->clut_table_data[0];
+
+	for (i = 0; i < num_in_channels; i++) {
+		lut->num_grid_points[i] = read_u8(src, clut_offset + i);
+	}
+
+	// Reverse the processing of transformation elements for mBA type.
+	lut->reversed = (type == LUT_MBA_TYPE);
+
+	lut->num_in_channels = num_in_channels;
+	lut->num_out_channels = num_out_channels;
+
+	if (matrix_offset) {
+		// read the matrix if we have it
+		lut->e00 = read_s15Fixed16Number(src, matrix_offset+4*0);
+		lut->e01 = read_s15Fixed16Number(src, matrix_offset+4*1);
+		lut->e02 = read_s15Fixed16Number(src, matrix_offset+4*2);
+		lut->e10 = read_s15Fixed16Number(src, matrix_offset+4*3);
+		lut->e11 = read_s15Fixed16Number(src, matrix_offset+4*4);
+		lut->e12 = read_s15Fixed16Number(src, matrix_offset+4*5);
+		lut->e20 = read_s15Fixed16Number(src, matrix_offset+4*6);
+		lut->e21 = read_s15Fixed16Number(src, matrix_offset+4*7);
+		lut->e22 = read_s15Fixed16Number(src, matrix_offset+4*8);
+		lut->e03 = read_s15Fixed16Number(src, matrix_offset+4*9);
+		lut->e13 = read_s15Fixed16Number(src, matrix_offset+4*10);
+		lut->e23 = read_s15Fixed16Number(src, matrix_offset+4*11);
+	}
+
+	if (a_curve_offset) {
+		read_nested_curveType(src, &lut->a_curves, num_in_channels, a_curve_offset);
+	}
+	if (m_curve_offset) {
+		read_nested_curveType(src, &lut->m_curves, num_out_channels, m_curve_offset);
+	}
+	if (b_curve_offset) {
+		read_nested_curveType(src, &lut->b_curves, num_out_channels, b_curve_offset);
+	} else {
+		invalid_source(src, "B curves required");
+	}
+
+	if (clut_offset) {
+		clut_precision = read_u8(src, clut_offset + 16);
+		if (clut_precision == 1) {
+			for (i = 0; i < clut_size; i++) {
+				lut->clut_table[i] = uInt8Number_to_float(read_uInt8Number(src, clut_offset + 20 + i*1));
+			}
+		} else if (clut_precision == 2) {
+			for (i = 0; i < clut_size; i++) {
+				lut->clut_table[i] = uInt16Number_to_float(read_uInt16Number(src, clut_offset + 20 + i*2));
+			}
+		} else {
+			invalid_source(src, "Invalid clut precision");
+		}
+	}
+
+	if (!src->valid) {
+		mAB_release(lut);
+		return NULL;
+	}
+
+	return lut;
+}
+
+static struct lutType *read_tag_lutType(struct mem_source *src, struct tag_index index, uint32_t tag_id)
+{
+	struct tag *tag = find_tag(index, tag_id);
+	uint32_t offset = tag->offset;
+	uint32_t type = read_u32(src, offset);
+	uint16_t num_input_table_entries;
+	uint16_t num_output_table_entries;
+	uint8_t in_chan, grid_points, out_chan;
+	uint32_t clut_offset, output_offset;
+	uint32_t clut_size;
+	size_t entry_size;
+	struct lutType *lut;
+	int i;
+
+	/* I'm not sure why the spec specifies a fixed number of entries for LUT8 tables even though
+	 * they have room for the num_entries fields */
+	if (type == LUT8_TYPE) {
+		num_input_table_entries = 256;
+		num_output_table_entries = 256;
+		entry_size = 1;
+	} else if (type == LUT16_TYPE) {
+		num_input_table_entries  = read_u16(src, offset + 48);
+		num_output_table_entries = read_u16(src, offset + 50);
+		entry_size = 2;
+	} else {
+		assert(0); // the caller checks that this doesn't happen
+		invalid_source(src, "Unexpected lut type");
+		return NULL;
+	}
+
+	in_chan     = read_u8(src, offset + 8);
+	out_chan    = read_u8(src, offset + 9);
+	grid_points = read_u8(src, offset + 10);
+
+	clut_size = pow(grid_points, in_chan);
+	if (clut_size > MAX_CLUT_SIZE) {
+		return NULL;
+	}
+
+	if (in_chan != 3 || out_chan != 3) {
+		return NULL;
+	}
+
+	lut = malloc(sizeof(struct lutType) + (num_input_table_entries * in_chan + clut_size*out_chan + num_output_table_entries * out_chan)*sizeof(float));
+	if (!lut) {
+		return NULL;
+	}
+
+	/* compute the offsets of tables */
+	lut->input_table  = &lut->table_data[0];
+	lut->clut_table   = &lut->table_data[in_chan*num_input_table_entries];
+	lut->output_table = &lut->table_data[in_chan*num_input_table_entries + clut_size*out_chan];
+
+	lut->num_input_table_entries  = num_input_table_entries;
+	lut->num_output_table_entries = num_output_table_entries;
+	lut->num_input_channels   = read_u8(src, offset + 8);
+	lut->num_output_channels  = read_u8(src, offset + 9);
+	lut->num_clut_grid_points = read_u8(src, offset + 10);
+	lut->e00 = read_s15Fixed16Number(src, offset+12);
+	lut->e01 = read_s15Fixed16Number(src, offset+16);
+	lut->e02 = read_s15Fixed16Number(src, offset+20);
+	lut->e10 = read_s15Fixed16Number(src, offset+24);
+	lut->e11 = read_s15Fixed16Number(src, offset+28);
+	lut->e12 = read_s15Fixed16Number(src, offset+32);
+	lut->e20 = read_s15Fixed16Number(src, offset+36);
+	lut->e21 = read_s15Fixed16Number(src, offset+40);
+	lut->e22 = read_s15Fixed16Number(src, offset+44);
+
+	for (i = 0; i < lut->num_input_table_entries * in_chan; i++) {
+		if (type == LUT8_TYPE) {
+			lut->input_table[i] = uInt8Number_to_float(read_uInt8Number(src, offset + 52 + i * entry_size));
+		} else {
+			lut->input_table[i] = uInt16Number_to_float(read_uInt16Number(src, offset + 52 + i * entry_size));
+		}
+	}
+
+	clut_offset = offset + 52 + lut->num_input_table_entries * in_chan * entry_size;
+	for (i = 0; i < clut_size * out_chan; i+=3) {
+		if (type == LUT8_TYPE) {
+			lut->clut_table[i+0] = uInt8Number_to_float(read_uInt8Number(src, clut_offset + i*entry_size + 0));
+			lut->clut_table[i+1] = uInt8Number_to_float(read_uInt8Number(src, clut_offset + i*entry_size + 1));
+			lut->clut_table[i+2] = uInt8Number_to_float(read_uInt8Number(src, clut_offset + i*entry_size + 2));
+		} else {
+			lut->clut_table[i+0] = uInt16Number_to_float(read_uInt16Number(src, clut_offset + i*entry_size + 0));
+			lut->clut_table[i+1] = uInt16Number_to_float(read_uInt16Number(src, clut_offset + i*entry_size + 2));
+			lut->clut_table[i+2] = uInt16Number_to_float(read_uInt16Number(src, clut_offset + i*entry_size + 4));
+		}
+	}
+
+	output_offset = clut_offset + clut_size * out_chan * entry_size;
+	for (i = 0; i < lut->num_output_table_entries * out_chan; i++) {
+		if (type == LUT8_TYPE) {
+			lut->output_table[i] = uInt8Number_to_float(read_uInt8Number(src, output_offset + i*entry_size));
+		} else {
+			lut->output_table[i] = uInt16Number_to_float(read_uInt16Number(src, output_offset + i*entry_size));
+		}
+	}
+
+	return lut;
+}
+
+static void read_rendering_intent(qcms_profile *profile, struct mem_source *src)
+{
+	profile->rendering_intent = read_u32(src, 64);
+	switch (profile->rendering_intent) {
+		case QCMS_INTENT_PERCEPTUAL:
+		case QCMS_INTENT_SATURATION:
+		case QCMS_INTENT_RELATIVE_COLORIMETRIC:
+		case QCMS_INTENT_ABSOLUTE_COLORIMETRIC:
+			break;
+		default:
+			invalid_source(src, "unknown rendering intent");
+	}
+}
+
+qcms_profile *qcms_profile_create(void)
+{
+	return calloc(sizeof(qcms_profile), 1);
+}
+
+
+
+/* build sRGB gamma table */
+/* based on cmsBuildParametricGamma() */
+static uint16_t *build_sRGB_gamma_table(int num_entries)
+{
+	int i;
+	/* taken from lcms: Build_sRGBGamma() */
+	double gamma = 2.4;
+	double a = 1./1.055;
+	double b = 0.055/1.055;
+	double c = 1./12.92;
+	double d = 0.04045;
+
+	uint16_t *table = malloc(sizeof(uint16_t) * num_entries);
+	if (!table)
+		return NULL;
+
+	for (i=0; i<num_entries; i++) {
+		double x = (double)i / (num_entries-1);
+		double y, output;
+		// IEC 61966-2.1 (sRGB)
+		// Y = (aX + b)^Gamma | X >= d
+		// Y = cX             | X < d
+		if (x >= d) {
+			double e = (a*x + b);
+			if (e > 0)
+				y = pow(e, gamma);
+			else
+				y = 0;
+		} else {
+			y = c*x;
+		}
+
+		// Saturate -- this could likely move to a separate function
+		output = y * 65535. + .5;
+		if (output > 65535.)
+			output = 65535;
+		if (output < 0)
+			output = 0;
+		table[i] = (uint16_t)floor(output);
+	}
+	return table;
+}
+
+static struct curveType *curve_from_table(uint16_t *table, int num_entries)
+{
+	struct curveType *curve;
+	int i;
+	curve = malloc(sizeof(struct curveType) + sizeof(uInt16Number)*num_entries);
+	if (!curve)
+		return NULL;
+	curve->type = CURVE_TYPE;
+	curve->count = num_entries;
+	for (i = 0; i < num_entries; i++) {
+		curve->data[i] = table[i];
+	}
+	return curve;
+}
+
+static uint16_t float_to_u8Fixed8Number(float a)
+{
+	if (a > (255.f + 255.f/256))
+		return 0xffff;
+	else if (a < 0.f)
+		return 0;
+	else
+		return floor(a*256.f + .5f);
+}
+
+static struct curveType *curve_from_gamma(float gamma)
+{
+	struct curveType *curve;
+	int num_entries = 1;
+	curve = malloc(sizeof(struct curveType) + sizeof(uInt16Number)*num_entries);
+	if (!curve)
+		return NULL;
+	curve->count = num_entries;
+	curve->data[0] = float_to_u8Fixed8Number(gamma);
+	return curve;
+}
+
+
+//XXX: it would be nice if we had a way of ensuring
+// everything in a profile was initialized regardless of how it was created
+
+//XXX: should this also be taking a black_point?
+/* similar to CGColorSpaceCreateCalibratedRGB */
+qcms_profile* qcms_profile_create_rgb_with_gamma(
+		qcms_CIE_xyY white_point,
+		qcms_CIE_xyYTRIPLE primaries,
+		float gamma)
+{
+	qcms_profile* profile = qcms_profile_create();
+	if (!profile)
+		return NO_MEM_PROFILE;
+
+	//XXX: should store the whitepoint
+	if (!set_rgb_colorants(profile, white_point, primaries)) {
+		qcms_profile_release(profile);
+		return INVALID_PROFILE;
+	}
+
+	profile->redTRC = curve_from_gamma(gamma);
+	profile->blueTRC = curve_from_gamma(gamma);
+	profile->greenTRC = curve_from_gamma(gamma);
+
+	if (!profile->redTRC || !profile->blueTRC || !profile->greenTRC) {
+		qcms_profile_release(profile);
+		return NO_MEM_PROFILE;
+	}
+	profile->class = DISPLAY_DEVICE_PROFILE;
+	profile->rendering_intent = QCMS_INTENT_PERCEPTUAL;
+	profile->color_space = RGB_SIGNATURE;
+	return profile;
+}
+
+qcms_profile* qcms_profile_create_rgb_with_table(
+		qcms_CIE_xyY white_point,
+		qcms_CIE_xyYTRIPLE primaries,
+		uint16_t *table, int num_entries)
+{
+	qcms_profile* profile = qcms_profile_create();
+	if (!profile)
+		return NO_MEM_PROFILE;
+
+	//XXX: should store the whitepoint
+	if (!set_rgb_colorants(profile, white_point, primaries)) {
+		qcms_profile_release(profile);
+		return INVALID_PROFILE;
+	}
+
+	profile->redTRC = curve_from_table(table, num_entries);
+	profile->blueTRC = curve_from_table(table, num_entries);
+	profile->greenTRC = curve_from_table(table, num_entries);
+
+	if (!profile->redTRC || !profile->blueTRC || !profile->greenTRC) {
+		qcms_profile_release(profile);
+		return NO_MEM_PROFILE;
+	}
+	profile->class = DISPLAY_DEVICE_PROFILE;
+	profile->rendering_intent = QCMS_INTENT_PERCEPTUAL;
+	profile->color_space = RGB_SIGNATURE;
+	return profile;
+}
+
+/* from lcms: cmsWhitePointFromTemp */
+/* tempK must be >= 4000. and <= 25000.
+ * similar to argyll: icx_DTEMP2XYZ() */
+static qcms_CIE_xyY white_point_from_temp(int temp_K)
+{
+	qcms_CIE_xyY white_point;
+	double x, y;
+	double T, T2, T3;
+	// double M1, M2;
+
+	// No optimization provided.
+	T = temp_K;
+	T2 = T*T;            // Square
+	T3 = T2*T;           // Cube
+
+	// For correlated color temperature (T) between 4000K and 7000K:
+	if (T >= 4000. && T <= 7000.) {
+		x = -4.6070*(1E9/T3) + 2.9678*(1E6/T2) + 0.09911*(1E3/T) + 0.244063;
+	} else {
+		// or for correlated color temperature (T) between 7000K and 25000K:
+		if (T > 7000.0 && T <= 25000.0) {
+			x = -2.0064*(1E9/T3) + 1.9018*(1E6/T2) + 0.24748*(1E3/T) + 0.237040;
+		} else {
+			assert(0 && "invalid temp");
+		}
+	}
+
+	// Obtain y(x)
+
+	y = -3.000*(x*x) + 2.870*x - 0.275;
+
+	// wave factors (not used, but here for futures extensions)
+
+	// M1 = (-1.3515 - 1.7703*x + 5.9114 *y)/(0.0241 + 0.2562*x - 0.7341*y);
+	// M2 = (0.0300 - 31.4424*x + 30.0717*y)/(0.0241 + 0.2562*x - 0.7341*y);
+
+	// Fill white_point struct
+	white_point.x = x;
+	white_point.y = y;
+	white_point.Y = 1.0;
+
+	return white_point;
+}
+
+qcms_profile* qcms_profile_sRGB(void)
+{
+	qcms_profile *profile;
+	uint16_t *table;
+
+	qcms_CIE_xyYTRIPLE Rec709Primaries = {
+		{0.6400, 0.3300, 1.0},
+		{0.3000, 0.6000, 1.0},
+		{0.1500, 0.0600, 1.0}
+	};
+	qcms_CIE_xyY D65;
+
+	D65 = white_point_from_temp(6504);
+
+	table = build_sRGB_gamma_table(1024);
+
+	if (!table)
+		return NO_MEM_PROFILE;
+
+	profile = qcms_profile_create_rgb_with_table(D65, Rec709Primaries, table, 1024);
+	free(table);
+	return profile;
+}
+
+
+/* qcms_profile_from_memory does not hold a reference to the memory passed in */
+qcms_profile* qcms_profile_from_memory(const void *mem, size_t size)
+{
+	uint32_t length;
+	struct mem_source source;
+	struct mem_source *src = &source;
+	struct tag_index index;
+	qcms_profile *profile;
+
+	source.buf = mem;
+	source.size = size;
+	source.valid = true;
+
+	length = read_u32(src, 0);
+	if (length <= size) {
+		// shrink the area that we can read if appropriate
+		source.size = length;
+	} else {
+		return INVALID_PROFILE;
+	}
+
+	/* ensure that the profile size is sane so it's easier to reason about */
+	if (source.size <= 64 || source.size >= MAX_PROFILE_SIZE)
+		return INVALID_PROFILE;
+
+	profile = qcms_profile_create();
+	if (!profile)
+		return NO_MEM_PROFILE;
+
+	check_CMM_type_signature(src);
+	check_profile_version(src);
+	read_class_signature(profile, src);
+	read_rendering_intent(profile, src);
+	read_color_space(profile, src);
+	read_pcs(profile, src);
+	//TODO read rest of profile stuff
+
+	if (!src->valid)
+		goto invalid_profile;
+
+	index = read_tag_table(profile, src);
+	if (!src->valid || !index.tags)
+		goto invalid_tag_table;
+
+	if (find_tag(index, TAG_CHAD)) {
+		profile->chromaticAdaption = read_tag_s15Fixed16ArrayType(src, index, TAG_CHAD);
+	} else {
+		profile->chromaticAdaption.invalid = true; //Signal the data is not present
+	}
+
+	if (profile->class == DISPLAY_DEVICE_PROFILE || profile->class == INPUT_DEVICE_PROFILE ||
+            profile->class == OUTPUT_DEVICE_PROFILE  || profile->class == COLOR_SPACE_PROFILE) {
+		if (profile->color_space == RGB_SIGNATURE) {
+			if (find_tag(index, TAG_A2B0)) {
+				if (read_u32(src, find_tag(index, TAG_A2B0)->offset) == LUT8_TYPE ||
+				    read_u32(src, find_tag(index, TAG_A2B0)->offset) == LUT16_TYPE) {
+					profile->A2B0 = read_tag_lutType(src, index, TAG_A2B0);
+				} else if (read_u32(src, find_tag(index, TAG_A2B0)->offset) == LUT_MAB_TYPE) {
+					profile->mAB = read_tag_lutmABType(src, index, TAG_A2B0);
+				}
+			}
+			if (find_tag(index, TAG_B2A0)) {
+				if (read_u32(src, find_tag(index, TAG_B2A0)->offset) == LUT8_TYPE ||
+				    read_u32(src, find_tag(index, TAG_B2A0)->offset) == LUT16_TYPE) {
+					profile->B2A0 = read_tag_lutType(src, index, TAG_B2A0);
+				} else if (read_u32(src, find_tag(index, TAG_B2A0)->offset) == LUT_MBA_TYPE) {
+					profile->mBA = read_tag_lutmABType(src, index, TAG_B2A0);
+				}
+			}
+			if (find_tag(index, TAG_rXYZ) || !qcms_supports_iccv4) {
+				profile->redColorant = read_tag_XYZType(src, index, TAG_rXYZ);
+				profile->greenColorant = read_tag_XYZType(src, index, TAG_gXYZ);
+				profile->blueColorant = read_tag_XYZType(src, index, TAG_bXYZ);
+			}
+
+			if (!src->valid)
+				goto invalid_tag_table;
+
+			if (find_tag(index, TAG_rTRC) || !qcms_supports_iccv4) {
+				profile->redTRC = read_tag_curveType(src, index, TAG_rTRC);
+				profile->greenTRC = read_tag_curveType(src, index, TAG_gTRC);
+				profile->blueTRC = read_tag_curveType(src, index, TAG_bTRC);
+
+				if (!profile->redTRC || !profile->blueTRC || !profile->greenTRC)
+					goto invalid_tag_table;
+			}
+		} else if (profile->color_space == GRAY_SIGNATURE) {
+
+			profile->grayTRC = read_tag_curveType(src, index, TAG_kTRC);
+			if (!profile->grayTRC)
+				goto invalid_tag_table;
+
+		} else {
+			assert(0 && "read_color_space protects against entering here");
+			goto invalid_tag_table;
+		}
+	} else {
+		goto invalid_tag_table;
+	}
+
+	if (!src->valid)
+		goto invalid_tag_table;
+
+	free(index.tags);
+
+	return profile;
+
+invalid_tag_table:
+	free(index.tags);
+invalid_profile:
+	qcms_profile_release(profile);
+	return INVALID_PROFILE;
+}
+
+qcms_intent qcms_profile_get_rendering_intent(qcms_profile *profile)
+{
+	return profile->rendering_intent;
+}
+
+icColorSpaceSignature
+qcms_profile_get_color_space(qcms_profile *profile)
+{
+	return profile->color_space;
+}
+
+static void lut_release(struct lutType *lut)
+{
+	free(lut);
+}
+
+void qcms_profile_release(qcms_profile *profile)
+{
+	if (profile->output_table_r)
+		precache_release(profile->output_table_r);
+	if (profile->output_table_g)
+		precache_release(profile->output_table_g);
+	if (profile->output_table_b)
+		precache_release(profile->output_table_b);
+
+	if (profile->A2B0)
+		lut_release(profile->A2B0);
+	if (profile->B2A0)
+		lut_release(profile->B2A0);
+
+	if (profile->mAB)
+		mAB_release(profile->mAB);
+	if (profile->mBA)
+		mAB_release(profile->mBA);
+
+	free(profile->redTRC);
+	free(profile->blueTRC);
+	free(profile->greenTRC);
+	free(profile->grayTRC);
+	free(profile);
+}
+
+
+#include <stdio.h>
+qcms_profile* qcms_profile_from_file(FILE *file)
+{
+	uint32_t length, remaining_length;
+	qcms_profile *profile;
+	size_t read_length;
+	be32 length_be;
+	void *data;
+
+	if (fread(&length_be, 1, sizeof(length_be), file) != sizeof(length_be))
+		return BAD_VALUE_PROFILE;
+
+	length = be32_to_cpu(length_be);
+	if (length > MAX_PROFILE_SIZE || length < sizeof(length_be))
+		return BAD_VALUE_PROFILE;
+
+	/* allocate room for the entire profile */
+	data = malloc(length);
+	if (!data)
+		return NO_MEM_PROFILE;
+
+	/* copy in length to the front so that the buffer will contain the entire profile */
+	*((be32*)data) = length_be;
+	remaining_length = length - sizeof(length_be);
+
+	/* read the rest profile */
+	read_length = fread((unsigned char*)data + sizeof(length_be), 1, remaining_length, file);
+	if (read_length != remaining_length) {
+		free(data);
+		return INVALID_PROFILE;
+	}
+
+	profile = qcms_profile_from_memory(data, length);
+	free(data);
+	return profile;
+}
+
+qcms_profile* qcms_profile_from_path(const char *path)
+{
+	qcms_profile *profile = NULL;
+	FILE *file = fopen(path, "rb");
+	if (file) {
+		profile = qcms_profile_from_file(file);
+		fclose(file);
+	}
+	return profile;
+}
+
+#ifdef _WIN32
+/* Unicode path version */
+qcms_profile* qcms_profile_from_unicode_path(const wchar_t *path)
+{
+	qcms_profile *profile = NULL;
+	FILE *file = _wfopen(path, L"rb");
+	if (file) {
+		profile = qcms_profile_from_file(file);
+		fclose(file);
+	}
+	return profile;
+}
+#endif