| /* |
| * Copyright 2018 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "../skcms.h" |
| #include "../skcms_internal.h" |
| #include <assert.h> |
| #include <limits.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| // Additional ICC signature values that are only used internally |
| enum { |
| // File signature |
| skcms_Signature_acsp = 0x61637370, |
| |
| // Tag signatures |
| skcms_Signature_rTRC = 0x72545243, |
| skcms_Signature_gTRC = 0x67545243, |
| skcms_Signature_bTRC = 0x62545243, |
| skcms_Signature_kTRC = 0x6B545243, |
| |
| skcms_Signature_rXYZ = 0x7258595A, |
| skcms_Signature_gXYZ = 0x6758595A, |
| skcms_Signature_bXYZ = 0x6258595A, |
| |
| skcms_Signature_A2B0 = 0x41324230, |
| skcms_Signature_A2B1 = 0x41324231, |
| skcms_Signature_mAB = 0x6D414220, |
| |
| skcms_Signature_CHAD = 0x63686164, |
| |
| // Type signatures |
| skcms_Signature_curv = 0x63757276, |
| skcms_Signature_mft1 = 0x6D667431, |
| skcms_Signature_mft2 = 0x6D667432, |
| skcms_Signature_para = 0x70617261, |
| skcms_Signature_sf32 = 0x73663332, |
| // XYZ is also a PCS signature, so it's defined in skcms.h |
| // skcms_Signature_XYZ = 0x58595A20, |
| }; |
| |
| static uint16_t read_big_u16(const uint8_t* ptr) { |
| uint16_t be; |
| memcpy(&be, ptr, sizeof(be)); |
| #if defined(_MSC_VER) |
| return _byteswap_ushort(be); |
| #else |
| return __builtin_bswap16(be); |
| #endif |
| } |
| |
| static uint32_t read_big_u32(const uint8_t* ptr) { |
| uint32_t be; |
| memcpy(&be, ptr, sizeof(be)); |
| #if defined(_MSC_VER) |
| return _byteswap_ulong(be); |
| #else |
| return __builtin_bswap32(be); |
| #endif |
| } |
| |
| static int32_t read_big_i32(const uint8_t* ptr) { |
| return (int32_t)read_big_u32(ptr); |
| } |
| |
| static float read_big_fixed(const uint8_t* ptr) { |
| return read_big_i32(ptr) * (1.0f / 65536.0f); |
| } |
| |
| // Maps to an in-memory profile so that fields line up to the locations specified |
| // in ICC.1:2010, section 7.2 |
| typedef struct { |
| uint8_t size [ 4]; |
| uint8_t cmm_type [ 4]; |
| uint8_t version [ 4]; |
| uint8_t profile_class [ 4]; |
| uint8_t data_color_space [ 4]; |
| uint8_t pcs [ 4]; |
| uint8_t creation_date_time [12]; |
| uint8_t signature [ 4]; |
| uint8_t platform [ 4]; |
| uint8_t flags [ 4]; |
| uint8_t device_manufacturer [ 4]; |
| uint8_t device_model [ 4]; |
| uint8_t device_attributes [ 8]; |
| uint8_t rendering_intent [ 4]; |
| uint8_t illuminant_X [ 4]; |
| uint8_t illuminant_Y [ 4]; |
| uint8_t illuminant_Z [ 4]; |
| uint8_t creator [ 4]; |
| uint8_t profile_id [16]; |
| uint8_t reserved [28]; |
| uint8_t tag_count [ 4]; // Technically not part of header, but required |
| } header_Layout; |
| |
| typedef struct { |
| uint8_t signature [4]; |
| uint8_t offset [4]; |
| uint8_t size [4]; |
| } tag_Layout; |
| |
| static const tag_Layout* get_tag_table(const skcms_ICCProfile* profile) { |
| return (const tag_Layout*)(profile->buffer + SAFE_SIZEOF(header_Layout)); |
| } |
| |
| // s15Fixed16ArrayType is technically variable sized, holding N values. However, the only valid |
| // use of the type is for the CHAD tag that stores exactly nine values. |
| typedef struct { |
| uint8_t type [ 4]; |
| uint8_t reserved [ 4]; |
| uint8_t values [36]; |
| } sf32_Layout; |
| |
| bool skcms_GetCHAD(const skcms_ICCProfile* profile, skcms_Matrix3x3* m) { |
| skcms_ICCTag tag; |
| if (!skcms_GetTagBySignature(profile, skcms_Signature_CHAD, &tag)) { |
| return false; |
| } |
| |
| if (tag.type != skcms_Signature_sf32 || tag.size < SAFE_SIZEOF(sf32_Layout)) { |
| return false; |
| } |
| |
| const sf32_Layout* sf32Tag = (const sf32_Layout*)tag.buf; |
| const uint8_t* values = sf32Tag->values; |
| for (int r = 0; r < 3; ++r) |
| for (int c = 0; c < 3; ++c, values += 4) { |
| m->vals[r][c] = read_big_fixed(values); |
| } |
| return true; |
| } |
| |
| // XYZType is technically variable sized, holding N XYZ triples. However, the only valid uses of |
| // the type are for tags/data that store exactly one triple. |
| typedef struct { |
| uint8_t type [4]; |
| uint8_t reserved [4]; |
| uint8_t X [4]; |
| uint8_t Y [4]; |
| uint8_t Z [4]; |
| } XYZ_Layout; |
| |
| static bool read_tag_xyz(const skcms_ICCTag* tag, float* x, float* y, float* z) { |
| if (tag->type != skcms_Signature_XYZ || tag->size < SAFE_SIZEOF(XYZ_Layout)) { |
| return false; |
| } |
| |
| const XYZ_Layout* xyzTag = (const XYZ_Layout*)tag->buf; |
| |
| *x = read_big_fixed(xyzTag->X); |
| *y = read_big_fixed(xyzTag->Y); |
| *z = read_big_fixed(xyzTag->Z); |
| return true; |
| } |
| |
| static bool read_to_XYZD50(const skcms_ICCTag* rXYZ, const skcms_ICCTag* gXYZ, |
| const skcms_ICCTag* bXYZ, skcms_Matrix3x3* toXYZ) { |
| return read_tag_xyz(rXYZ, &toXYZ->vals[0][0], &toXYZ->vals[1][0], &toXYZ->vals[2][0]) && |
| read_tag_xyz(gXYZ, &toXYZ->vals[0][1], &toXYZ->vals[1][1], &toXYZ->vals[2][1]) && |
| read_tag_xyz(bXYZ, &toXYZ->vals[0][2], &toXYZ->vals[1][2], &toXYZ->vals[2][2]); |
| } |
| |
| typedef struct { |
| uint8_t type [4]; |
| uint8_t reserved_a [4]; |
| uint8_t function_type [2]; |
| uint8_t reserved_b [2]; |
| uint8_t parameters [ ]; // 1, 3, 4, 5, or 7 s15.16 parameters, depending on function_type |
| } para_Layout; |
| |
| static bool read_curve_para(const uint8_t* buf, uint32_t size, |
| skcms_Curve* curve, uint32_t* curve_size) { |
| if (size < SAFE_SIZEOF(para_Layout)) { |
| return false; |
| } |
| |
| const para_Layout* paraTag = (const para_Layout*)buf; |
| |
| enum { kG = 0, kGAB = 1, kGABC = 2, kGABCD = 3, kGABCDEF = 4 }; |
| uint16_t function_type = read_big_u16(paraTag->function_type); |
| if (function_type > kGABCDEF) { |
| return false; |
| } |
| |
| static const uint32_t curve_bytes[] = { 4, 12, 16, 20, 28 }; |
| if (size < SAFE_SIZEOF(para_Layout) + curve_bytes[function_type]) { |
| return false; |
| } |
| |
| if (curve_size) { |
| *curve_size = SAFE_SIZEOF(para_Layout) + curve_bytes[function_type]; |
| } |
| |
| curve->table_entries = 0; |
| curve->parametric.a = 1.0f; |
| curve->parametric.b = 0.0f; |
| curve->parametric.c = 0.0f; |
| curve->parametric.d = 0.0f; |
| curve->parametric.e = 0.0f; |
| curve->parametric.f = 0.0f; |
| curve->parametric.g = read_big_fixed(paraTag->parameters); |
| |
| switch (function_type) { |
| case kGAB: |
| curve->parametric.a = read_big_fixed(paraTag->parameters + 4); |
| curve->parametric.b = read_big_fixed(paraTag->parameters + 8); |
| if (curve->parametric.a == 0) { |
| return false; |
| } |
| curve->parametric.d = -curve->parametric.b / curve->parametric.a; |
| break; |
| case kGABC: |
| curve->parametric.a = read_big_fixed(paraTag->parameters + 4); |
| curve->parametric.b = read_big_fixed(paraTag->parameters + 8); |
| curve->parametric.e = read_big_fixed(paraTag->parameters + 12); |
| if (curve->parametric.a == 0) { |
| return false; |
| } |
| curve->parametric.d = -curve->parametric.b / curve->parametric.a; |
| curve->parametric.f = curve->parametric.e; |
| break; |
| case kGABCD: |
| curve->parametric.a = read_big_fixed(paraTag->parameters + 4); |
| curve->parametric.b = read_big_fixed(paraTag->parameters + 8); |
| curve->parametric.c = read_big_fixed(paraTag->parameters + 12); |
| curve->parametric.d = read_big_fixed(paraTag->parameters + 16); |
| break; |
| case kGABCDEF: |
| curve->parametric.a = read_big_fixed(paraTag->parameters + 4); |
| curve->parametric.b = read_big_fixed(paraTag->parameters + 8); |
| curve->parametric.c = read_big_fixed(paraTag->parameters + 12); |
| curve->parametric.d = read_big_fixed(paraTag->parameters + 16); |
| curve->parametric.e = read_big_fixed(paraTag->parameters + 20); |
| curve->parametric.f = read_big_fixed(paraTag->parameters + 24); |
| break; |
| } |
| return skcms_TransferFunction_isValid(&curve->parametric); |
| } |
| |
| typedef struct { |
| uint8_t type [4]; |
| uint8_t reserved [4]; |
| uint8_t value_count [4]; |
| uint8_t parameters [ ]; // value_count parameters (8.8 if 1, uint16 (n*65535) if > 1) |
| } curv_Layout; |
| |
| static bool read_curve_curv(const uint8_t* buf, uint32_t size, |
| skcms_Curve* curve, uint32_t* curve_size) { |
| if (size < SAFE_SIZEOF(curv_Layout)) { |
| return false; |
| } |
| |
| const curv_Layout* curvTag = (const curv_Layout*)buf; |
| |
| uint32_t value_count = read_big_u32(curvTag->value_count); |
| if (size < SAFE_SIZEOF(curv_Layout) + value_count * SAFE_SIZEOF(uint16_t)) { |
| return false; |
| } |
| |
| if (curve_size) { |
| *curve_size = SAFE_SIZEOF(curv_Layout) + value_count * SAFE_SIZEOF(uint16_t); |
| } |
| |
| if (value_count < 2) { |
| curve->table_entries = 0; |
| curve->parametric.a = 1.0f; |
| curve->parametric.b = 0.0f; |
| curve->parametric.c = 0.0f; |
| curve->parametric.d = 0.0f; |
| curve->parametric.e = 0.0f; |
| curve->parametric.f = 0.0f; |
| if (value_count == 0) { |
| // Empty tables are a shorthand for an identity curve |
| curve->parametric.g = 1.0f; |
| } else { |
| // Single entry tables are a shorthand for simple gamma |
| curve->parametric.g = read_big_u16(curvTag->parameters) * (1.0f / 256.0f); |
| } |
| } else { |
| curve->table_8 = NULL; |
| curve->table_16 = curvTag->parameters; |
| curve->table_entries = value_count; |
| } |
| |
| return true; |
| } |
| |
| // Parses both curveType and parametricCurveType data. Ensures that at most 'size' bytes are read. |
| // If curve_size is not NULL, writes the number of bytes used by the curve in (*curve_size). |
| static bool read_curve(const uint8_t* buf, uint32_t size, |
| skcms_Curve* curve, uint32_t* curve_size) { |
| if (!buf || size < 4 || !curve) { |
| return false; |
| } |
| |
| uint32_t type = read_big_u32(buf); |
| if (type == skcms_Signature_para) { |
| return read_curve_para(buf, size, curve, curve_size); |
| } else if (type == skcms_Signature_curv) { |
| return read_curve_curv(buf, size, curve, curve_size); |
| } |
| |
| return false; |
| } |
| |
| // mft1 and mft2 share a large chunk of data |
| typedef struct { |
| uint8_t type [ 4]; |
| uint8_t reserved_a [ 4]; |
| uint8_t input_channels [ 1]; |
| uint8_t output_channels [ 1]; |
| uint8_t grid_points [ 1]; |
| uint8_t reserved_b [ 1]; |
| uint8_t matrix [36]; |
| } mft_CommonLayout; |
| |
| typedef struct { |
| mft_CommonLayout common [ 1]; |
| |
| uint8_t tables [ ]; |
| } mft1_Layout; |
| |
| typedef struct { |
| mft_CommonLayout common [ 1]; |
| |
| uint8_t input_table_entries [ 2]; |
| uint8_t output_table_entries [ 2]; |
| uint8_t tables [ ]; |
| } mft2_Layout; |
| |
| static bool read_mft_common(const mft_CommonLayout* mftTag, skcms_A2B* a2b) { |
| // MFT matrices are applied before the first set of curves, but must be identity unless the |
| // input is PCSXYZ. We don't support PCSXYZ profiles, so we ignore this matrix. Note that the |
| // matrix in skcms_A2B is applied later in the pipe, so supporting this would require another |
| // field/flag. |
| a2b->matrix_channels = 0; |
| |
| a2b->input_channels = mftTag->input_channels[0]; |
| a2b->output_channels = mftTag->output_channels[0]; |
| |
| // We require exactly three (ie XYZ/Lab/RGB) output channels |
| if (a2b->output_channels != ARRAY_COUNT(a2b->output_curves)) { |
| return false; |
| } |
| // We require at least one, and no more than four (ie CMYK) input channels |
| if (a2b->input_channels < 1 || a2b->input_channels > ARRAY_COUNT(a2b->input_curves)) { |
| return false; |
| } |
| |
| for (uint32_t i = 0; i < a2b->input_channels; ++i) { |
| a2b->grid_points[i] = mftTag->grid_points[0]; |
| } |
| // The grid only makes sense with at least two points along each axis |
| if (a2b->grid_points[0] < 2) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static bool init_a2b_tables(const uint8_t* table_base, uint64_t max_tables_len, uint32_t byte_width, |
| uint32_t input_table_entries, uint32_t output_table_entries, |
| skcms_A2B* a2b) { |
| // byte_width is 1 or 2, [input|output]_table_entries are in [2, 4096], so no overflow |
| uint32_t byte_len_per_input_table = input_table_entries * byte_width; |
| uint32_t byte_len_per_output_table = output_table_entries * byte_width; |
| |
| // [input|output]_channels are <= 4, so still no overflow |
| uint32_t byte_len_all_input_tables = a2b->input_channels * byte_len_per_input_table; |
| uint32_t byte_len_all_output_tables = a2b->output_channels * byte_len_per_output_table; |
| |
| uint64_t grid_size = a2b->output_channels * byte_width; |
| for (uint32_t axis = 0; axis < a2b->input_channels; ++axis) { |
| grid_size *= a2b->grid_points[axis]; |
| } |
| |
| if (max_tables_len < byte_len_all_input_tables + grid_size + byte_len_all_output_tables) { |
| return false; |
| } |
| |
| for (uint32_t i = 0; i < a2b->input_channels; ++i) { |
| a2b->input_curves[i].table_entries = input_table_entries; |
| if (byte_width == 1) { |
| a2b->input_curves[i].table_8 = table_base + i * byte_len_per_input_table; |
| a2b->input_curves[i].table_16 = NULL; |
| } else { |
| a2b->input_curves[i].table_8 = NULL; |
| a2b->input_curves[i].table_16 = table_base + i * byte_len_per_input_table; |
| } |
| } |
| |
| if (byte_width == 1) { |
| a2b->grid_8 = table_base + byte_len_all_input_tables; |
| a2b->grid_16 = NULL; |
| } else { |
| a2b->grid_8 = NULL; |
| a2b->grid_16 = table_base + byte_len_all_input_tables; |
| } |
| |
| const uint8_t* output_table_base = table_base + byte_len_all_input_tables + grid_size; |
| for (uint32_t i = 0; i < a2b->output_channels; ++i) { |
| a2b->output_curves[i].table_entries = output_table_entries; |
| if (byte_width == 1) { |
| a2b->output_curves[i].table_8 = output_table_base + i * byte_len_per_output_table; |
| a2b->output_curves[i].table_16 = NULL; |
| } else { |
| a2b->output_curves[i].table_8 = NULL; |
| a2b->output_curves[i].table_16 = output_table_base + i * byte_len_per_output_table; |
| } |
| } |
| |
| return true; |
| } |
| |
| static bool read_tag_mft1(const skcms_ICCTag* tag, skcms_A2B* a2b) { |
| if (tag->size < SAFE_SIZEOF(mft1_Layout)) { |
| return false; |
| } |
| |
| const mft1_Layout* mftTag = (const mft1_Layout*)tag->buf; |
| if (!read_mft_common(mftTag->common, a2b)) { |
| return false; |
| } |
| |
| uint32_t input_table_entries = 256; |
| uint32_t output_table_entries = 256; |
| |
| return init_a2b_tables(mftTag->tables, tag->size - SAFE_SIZEOF(mft1_Layout), 1, |
| input_table_entries, output_table_entries, a2b); |
| } |
| |
| static bool read_tag_mft2(const skcms_ICCTag* tag, skcms_A2B* a2b) { |
| if (tag->size < SAFE_SIZEOF(mft2_Layout)) { |
| return false; |
| } |
| |
| const mft2_Layout* mftTag = (const mft2_Layout*)tag->buf; |
| if (!read_mft_common(mftTag->common, a2b)) { |
| return false; |
| } |
| |
| uint32_t input_table_entries = read_big_u16(mftTag->input_table_entries); |
| uint32_t output_table_entries = read_big_u16(mftTag->output_table_entries); |
| |
| // ICC spec mandates that 2 <= table_entries <= 4096 |
| if (input_table_entries < 2 || input_table_entries > 4096 || |
| output_table_entries < 2 || output_table_entries > 4096) { |
| return false; |
| } |
| |
| return init_a2b_tables(mftTag->tables, tag->size - SAFE_SIZEOF(mft2_Layout), 2, |
| input_table_entries, output_table_entries, a2b); |
| } |
| |
| static bool read_curves(const uint8_t* buf, uint32_t size, uint32_t curve_offset, |
| uint32_t num_curves, skcms_Curve* curves) { |
| for (uint32_t i = 0; i < num_curves; ++i) { |
| if (curve_offset > size) { |
| return false; |
| } |
| |
| uint32_t curve_bytes; |
| if (!read_curve(buf + curve_offset, size - curve_offset, &curves[i], &curve_bytes)) { |
| return false; |
| } |
| |
| if (curve_bytes > UINT32_MAX - 3) { |
| return false; |
| } |
| curve_bytes = (curve_bytes + 3) & ~3U; |
| |
| uint64_t new_offset_64 = (uint64_t)curve_offset + curve_bytes; |
| curve_offset = (uint32_t)new_offset_64; |
| if (new_offset_64 != curve_offset) { |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| typedef struct { |
| uint8_t type [ 4]; |
| uint8_t reserved_a [ 4]; |
| uint8_t input_channels [ 1]; |
| uint8_t output_channels [ 1]; |
| uint8_t reserved_b [ 2]; |
| uint8_t b_curve_offset [ 4]; |
| uint8_t matrix_offset [ 4]; |
| uint8_t m_curve_offset [ 4]; |
| uint8_t clut_offset [ 4]; |
| uint8_t a_curve_offset [ 4]; |
| } mAB_Layout; |
| |
| typedef struct { |
| uint8_t grid_points [16]; |
| uint8_t grid_byte_width [ 1]; |
| uint8_t reserved [ 3]; |
| uint8_t data [ ]; |
| } mABCLUT_Layout; |
| |
| static bool read_tag_mab(const skcms_ICCTag* tag, skcms_A2B* a2b, bool pcs_is_xyz) { |
| if (tag->size < SAFE_SIZEOF(mAB_Layout)) { |
| return false; |
| } |
| |
| const mAB_Layout* mABTag = (const mAB_Layout*)tag->buf; |
| |
| a2b->input_channels = mABTag->input_channels[0]; |
| a2b->output_channels = mABTag->output_channels[0]; |
| |
| // We require exactly three (ie XYZ/Lab/RGB) output channels |
| if (a2b->output_channels != ARRAY_COUNT(a2b->output_curves)) { |
| return false; |
| } |
| // We require no more than four (ie CMYK) input channels |
| if (a2b->input_channels > ARRAY_COUNT(a2b->input_curves)) { |
| return false; |
| } |
| |
| uint32_t b_curve_offset = read_big_u32(mABTag->b_curve_offset); |
| uint32_t matrix_offset = read_big_u32(mABTag->matrix_offset); |
| uint32_t m_curve_offset = read_big_u32(mABTag->m_curve_offset); |
| uint32_t clut_offset = read_big_u32(mABTag->clut_offset); |
| uint32_t a_curve_offset = read_big_u32(mABTag->a_curve_offset); |
| |
| // "B" curves must be present |
| if (0 == b_curve_offset) { |
| return false; |
| } |
| |
| if (!read_curves(tag->buf, tag->size, b_curve_offset, a2b->output_channels, |
| a2b->output_curves)) { |
| return false; |
| } |
| |
| // "M" curves and Matrix must be used together |
| if (0 != m_curve_offset) { |
| if (0 == matrix_offset) { |
| return false; |
| } |
| a2b->matrix_channels = a2b->output_channels; |
| if (!read_curves(tag->buf, tag->size, m_curve_offset, a2b->matrix_channels, |
| a2b->matrix_curves)) { |
| return false; |
| } |
| |
| // Read matrix, which is stored as a row-major 3x3, followed by the fourth column |
| if (tag->size < matrix_offset + 12 * SAFE_SIZEOF(uint32_t)) { |
| return false; |
| } |
| float encoding_factor = pcs_is_xyz ? 65535 / 32768.0f : 1.0f; |
| const uint8_t* mtx_buf = tag->buf + matrix_offset; |
| a2b->matrix.vals[0][0] = encoding_factor * read_big_fixed(mtx_buf + 0); |
| a2b->matrix.vals[0][1] = encoding_factor * read_big_fixed(mtx_buf + 4); |
| a2b->matrix.vals[0][2] = encoding_factor * read_big_fixed(mtx_buf + 8); |
| a2b->matrix.vals[1][0] = encoding_factor * read_big_fixed(mtx_buf + 12); |
| a2b->matrix.vals[1][1] = encoding_factor * read_big_fixed(mtx_buf + 16); |
| a2b->matrix.vals[1][2] = encoding_factor * read_big_fixed(mtx_buf + 20); |
| a2b->matrix.vals[2][0] = encoding_factor * read_big_fixed(mtx_buf + 24); |
| a2b->matrix.vals[2][1] = encoding_factor * read_big_fixed(mtx_buf + 28); |
| a2b->matrix.vals[2][2] = encoding_factor * read_big_fixed(mtx_buf + 32); |
| a2b->matrix.vals[0][3] = encoding_factor * read_big_fixed(mtx_buf + 36); |
| a2b->matrix.vals[1][3] = encoding_factor * read_big_fixed(mtx_buf + 40); |
| a2b->matrix.vals[2][3] = encoding_factor * read_big_fixed(mtx_buf + 44); |
| } else { |
| if (0 != matrix_offset) { |
| return false; |
| } |
| a2b->matrix_channels = 0; |
| } |
| |
| // "A" curves and CLUT must be used together |
| if (0 != a_curve_offset) { |
| if (0 == clut_offset) { |
| return false; |
| } |
| if (!read_curves(tag->buf, tag->size, a_curve_offset, a2b->input_channels, |
| a2b->input_curves)) { |
| return false; |
| } |
| |
| if (tag->size < clut_offset + SAFE_SIZEOF(mABCLUT_Layout)) { |
| return false; |
| } |
| const mABCLUT_Layout* clut = (const mABCLUT_Layout*)(tag->buf + clut_offset); |
| |
| if (clut->grid_byte_width[0] == 1) { |
| a2b->grid_8 = clut->data; |
| a2b->grid_16 = NULL; |
| } else if (clut->grid_byte_width[0] == 2) { |
| a2b->grid_8 = NULL; |
| a2b->grid_16 = clut->data; |
| } else { |
| return false; |
| } |
| |
| uint64_t grid_size = a2b->output_channels * clut->grid_byte_width[0]; |
| for (uint32_t i = 0; i < a2b->input_channels; ++i) { |
| a2b->grid_points[i] = clut->grid_points[i]; |
| // The grid only makes sense with at least two points along each axis |
| if (a2b->grid_points[i] < 2) { |
| return false; |
| } |
| grid_size *= a2b->grid_points[i]; |
| } |
| if (tag->size < clut_offset + SAFE_SIZEOF(mABCLUT_Layout) + grid_size) { |
| return false; |
| } |
| } else { |
| if (0 != clut_offset) { |
| return false; |
| } |
| |
| // If there is no CLUT, the number of input and output channels must match |
| if (a2b->input_channels != a2b->output_channels) { |
| return false; |
| } |
| |
| // Zero out the number of input channels to signal that we're skipping this stage |
| a2b->input_channels = 0; |
| } |
| |
| return true; |
| } |
| |
| static bool read_a2b(const skcms_ICCTag* tag, skcms_A2B* a2b, bool pcs_is_xyz) { |
| bool ok = false; |
| if (tag->type == skcms_Signature_mft1) { |
| ok = read_tag_mft1(tag, a2b); |
| } else if (tag->type == skcms_Signature_mft2) { |
| ok = read_tag_mft2(tag, a2b); |
| } else if (tag->type == skcms_Signature_mAB) { |
| ok = read_tag_mab(tag, a2b, pcs_is_xyz); |
| } |
| if (!ok) { |
| return false; |
| } |
| |
| // Detect and canonicalize identity tables. |
| skcms_Curve* curves[] = { |
| a2b->input_channels > 0 ? a2b->input_curves + 0 : NULL, |
| a2b->input_channels > 1 ? a2b->input_curves + 1 : NULL, |
| a2b->input_channels > 2 ? a2b->input_curves + 2 : NULL, |
| a2b->input_channels > 3 ? a2b->input_curves + 3 : NULL, |
| a2b->matrix_channels > 0 ? a2b->matrix_curves + 0 : NULL, |
| a2b->matrix_channels > 1 ? a2b->matrix_curves + 1 : NULL, |
| a2b->matrix_channels > 2 ? a2b->matrix_curves + 2 : NULL, |
| a2b->output_channels > 0 ? a2b->output_curves + 0 : NULL, |
| a2b->output_channels > 1 ? a2b->output_curves + 1 : NULL, |
| a2b->output_channels > 2 ? a2b->output_curves + 2 : NULL, |
| }; |
| |
| for (int i = 0; i < ARRAY_COUNT(curves); i++) { |
| skcms_Curve* curve = curves[i]; |
| |
| if (curve && curve->table_entries && curve->table_entries <= (uint32_t)INT_MAX) { |
| int N = (int)curve->table_entries; |
| |
| float c,d,f; |
| if (N == skcms_fit_linear(curve, N, 1.0f/(2*N), &c,&d,&f) |
| && c == 1.0f |
| && f == 0.0f) { |
| curve->table_entries = 0; |
| curve->table_8 = NULL; |
| curve->table_16 = NULL; |
| curve->parametric = (skcms_TransferFunction){1,1,0,0,0,0,0}; |
| } |
| } |
| } |
| |
| return true; |
| } |
| |
| void skcms_GetTagByIndex(const skcms_ICCProfile* profile, uint32_t idx, skcms_ICCTag* tag) { |
| if (!profile || !profile->buffer || !tag) { return; } |
| if (idx > profile->tag_count) { return; } |
| const tag_Layout* tags = get_tag_table(profile); |
| tag->signature = read_big_u32(tags[idx].signature); |
| tag->size = read_big_u32(tags[idx].size); |
| tag->buf = read_big_u32(tags[idx].offset) + profile->buffer; |
| tag->type = read_big_u32(tag->buf); |
| } |
| |
| bool skcms_GetTagBySignature(const skcms_ICCProfile* profile, uint32_t sig, skcms_ICCTag* tag) { |
| if (!profile || !profile->buffer || !tag) { return false; } |
| const tag_Layout* tags = get_tag_table(profile); |
| for (uint32_t i = 0; i < profile->tag_count; ++i) { |
| if (read_big_u32(tags[i].signature) == sig) { |
| tag->signature = sig; |
| tag->size = read_big_u32(tags[i].size); |
| tag->buf = read_big_u32(tags[i].offset) + profile->buffer; |
| tag->type = read_big_u32(tag->buf); |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| static bool usable_as_src(const skcms_ICCProfile* profile) { |
| return profile->has_A2B |
| || (profile->has_trc && profile->has_toXYZD50); |
| } |
| |
| bool skcms_Parse(const void* buf, size_t len, skcms_ICCProfile* profile) { |
| assert(SAFE_SIZEOF(header_Layout) == 132); |
| |
| if (!profile) { |
| return false; |
| } |
| memset(profile, 0, SAFE_SIZEOF(*profile)); |
| |
| if (len < SAFE_SIZEOF(header_Layout)) { |
| return false; |
| } |
| |
| // Byte-swap all header fields |
| const header_Layout* header = buf; |
| profile->buffer = buf; |
| profile->size = read_big_u32(header->size); |
| uint32_t version = read_big_u32(header->version); |
| profile->data_color_space = read_big_u32(header->data_color_space); |
| profile->pcs = read_big_u32(header->pcs); |
| uint32_t signature = read_big_u32(header->signature); |
| float illuminant_X = read_big_fixed(header->illuminant_X); |
| float illuminant_Y = read_big_fixed(header->illuminant_Y); |
| float illuminant_Z = read_big_fixed(header->illuminant_Z); |
| profile->tag_count = read_big_u32(header->tag_count); |
| |
| // Validate signature, size (smaller than buffer, large enough to hold tag table), |
| // and major version |
| uint64_t tag_table_size = profile->tag_count * SAFE_SIZEOF(tag_Layout); |
| if (signature != skcms_Signature_acsp || |
| profile->size > len || |
| profile->size < SAFE_SIZEOF(header_Layout) + tag_table_size || |
| (version >> 24) > 4) { |
| return false; |
| } |
| |
| // Validate that illuminant is D50 white |
| if (fabsf_(illuminant_X - 0.9642f) > 0.0100f || |
| fabsf_(illuminant_Y - 1.0000f) > 0.0100f || |
| fabsf_(illuminant_Z - 0.8249f) > 0.0100f) { |
| return false; |
| } |
| |
| // Validate that all tag entries have sane offset + size |
| const tag_Layout* tags = get_tag_table(profile); |
| for (uint32_t i = 0; i < profile->tag_count; ++i) { |
| uint32_t tag_offset = read_big_u32(tags[i].offset); |
| uint32_t tag_size = read_big_u32(tags[i].size); |
| uint64_t tag_end = (uint64_t)tag_offset + (uint64_t)tag_size; |
| if (tag_size < 4 || tag_end > profile->size) { |
| return false; |
| } |
| } |
| |
| if (profile->pcs != skcms_Signature_XYZ && profile->pcs != skcms_Signature_Lab) { |
| return false; |
| } |
| |
| bool pcs_is_xyz = profile->pcs == skcms_Signature_XYZ; |
| |
| // Pre-parse commonly used tags. |
| skcms_ICCTag kTRC; |
| if (profile->data_color_space == skcms_Signature_Gray && |
| skcms_GetTagBySignature(profile, skcms_Signature_kTRC, &kTRC)) { |
| if (!read_curve(kTRC.buf, kTRC.size, &profile->trc[0], NULL)) { |
| // Malformed tag |
| return false; |
| } |
| profile->trc[1] = profile->trc[0]; |
| profile->trc[2] = profile->trc[0]; |
| profile->has_trc = true; |
| |
| if (pcs_is_xyz) { |
| profile->toXYZD50.vals[0][0] = illuminant_X; |
| profile->toXYZD50.vals[1][1] = illuminant_Y; |
| profile->toXYZD50.vals[2][2] = illuminant_Z; |
| profile->has_toXYZD50 = true; |
| } |
| } else { |
| skcms_ICCTag rTRC, gTRC, bTRC; |
| if (skcms_GetTagBySignature(profile, skcms_Signature_rTRC, &rTRC) && |
| skcms_GetTagBySignature(profile, skcms_Signature_gTRC, &gTRC) && |
| skcms_GetTagBySignature(profile, skcms_Signature_bTRC, &bTRC)) { |
| if (!read_curve(rTRC.buf, rTRC.size, &profile->trc[0], NULL) || |
| !read_curve(gTRC.buf, gTRC.size, &profile->trc[1], NULL) || |
| !read_curve(bTRC.buf, bTRC.size, &profile->trc[2], NULL)) { |
| // Malformed TRC tags |
| return false; |
| } |
| profile->has_trc = true; |
| } |
| |
| skcms_ICCTag rXYZ, gXYZ, bXYZ; |
| if (skcms_GetTagBySignature(profile, skcms_Signature_rXYZ, &rXYZ) && |
| skcms_GetTagBySignature(profile, skcms_Signature_gXYZ, &gXYZ) && |
| skcms_GetTagBySignature(profile, skcms_Signature_bXYZ, &bXYZ)) { |
| if (!read_to_XYZD50(&rXYZ, &gXYZ, &bXYZ, &profile->toXYZD50)) { |
| // Malformed XYZ tags |
| return false; |
| } |
| profile->has_toXYZD50 = true; |
| } |
| } |
| |
| skcms_ICCTag a2b_tag; |
| |
| // For now, we're preferring A2B0, like Skia does and the ICC spec tells us to. |
| // TODO: prefer A2B1 (relative colormetric) over A2B0 (perceptual)? |
| // This breaks with the ICC spec, but we think it's a good idea, given that TRC curves |
| // and all our known users are thinking exclusively in terms of relative colormetric. |
| const uint32_t sigs[] = { skcms_Signature_A2B0, skcms_Signature_A2B1 }; |
| for (int i = 0; i < ARRAY_COUNT(sigs); i++) { |
| if (skcms_GetTagBySignature(profile, sigs[i], &a2b_tag)) { |
| if (!read_a2b(&a2b_tag, &profile->A2B, pcs_is_xyz)) { |
| // Malformed A2B tag |
| return false; |
| } |
| profile->has_A2B = true; |
| break; |
| } |
| } |
| |
| return usable_as_src(profile); |
| } |
| |
| |
| const skcms_ICCProfile* skcms_sRGB_profile() { |
| static const skcms_ICCProfile sRGB_profile = { |
| // These fields are moot when not a skcms_Parse()'d profile. |
| .buffer = NULL, |
| .size = 0, |
| .tag_count = 0, |
| |
| // We choose to represent sRGB with its canonical transfer function, |
| // and with its canonical XYZD50 gamut matrix. |
| .data_color_space = skcms_Signature_RGB, |
| .pcs = skcms_Signature_XYZ, |
| .has_trc = true, |
| .has_toXYZD50 = true, |
| .has_A2B = false, |
| |
| .trc = { |
| {{0, {2.4f, (float)(1/1.055), (float)(0.055/1.055), (float)(1/12.92), 0.04045f, 0, 0 }}}, |
| {{0, {2.4f, (float)(1/1.055), (float)(0.055/1.055), (float)(1/12.92), 0.04045f, 0, 0 }}}, |
| {{0, {2.4f, (float)(1/1.055), (float)(0.055/1.055), (float)(1/12.92), 0.04045f, 0, 0 }}}, |
| }, |
| |
| .toXYZD50 = {{ |
| { 0.436065674f, 0.385147095f, 0.143066406f }, |
| { 0.222488403f, 0.716873169f, 0.060607910f }, |
| { 0.013916016f, 0.097076416f, 0.714096069f }, |
| }}, |
| }; |
| return &sRGB_profile; |
| } |
| |
| const skcms_ICCProfile* skcms_XYZD50_profile() { |
| static const skcms_ICCProfile XYZD50_profile = { |
| .buffer = NULL, |
| .size = 0, |
| .tag_count = 0, |
| |
| .data_color_space = skcms_Signature_RGB, |
| .pcs = skcms_Signature_XYZ, |
| .has_trc = true, |
| .has_toXYZD50 = true, |
| .has_A2B = false, |
| |
| .trc = { |
| {{0, {1,1,0,0,0,0,0}}}, |
| {{0, {1,1,0,0,0,0,0}}}, |
| {{0, {1,1,0,0,0,0,0}}}, |
| }, |
| |
| .toXYZD50 = {{ |
| {1,0,0}, |
| {0,1,0}, |
| {0,0,1}, |
| }}, |
| }; |
| |
| return &XYZD50_profile; |
| } |
| |
| const skcms_TransferFunction* skcms_sRGB_TransferFunction() { |
| return &skcms_sRGB_profile()->trc[0].parametric; |
| } |
| |
| const skcms_TransferFunction* skcms_sRGB_Inverse_TransferFunction() { |
| static const skcms_TransferFunction sRGB_inv = |
| { (float)(1/2.4), 1.137119f, 0, 12.92f, 0.0031308f, -0.055f, 0 }; |
| return &sRGB_inv; |
| } |
| |
| const skcms_TransferFunction* skcms_Identity_TransferFunction() { |
| static const skcms_TransferFunction identity = {1,1,0,0,0,0,0}; |
| return &identity; |
| } |
| |
| const uint8_t skcms_252_random_bytes[] = { |
| 8, 179, 128, 204, 253, 38, 134, 184, 68, 102, 32, 138, 99, 39, 169, 215, |
| 119, 26, 3, 223, 95, 239, 52, 132, 114, 74, 81, 234, 97, 116, 244, 205, 30, |
| 154, 173, 12, 51, 159, 122, 153, 61, 226, 236, 178, 229, 55, 181, 220, 191, |
| 194, 160, 126, 168, 82, 131, 18, 180, 245, 163, 22, 246, 69, 235, 252, 57, |
| 108, 14, 6, 152, 240, 255, 171, 242, 20, 227, 177, 238, 96, 85, 16, 211, |
| 70, 200, 149, 155, 146, 127, 145, 100, 151, 109, 19, 165, 208, 195, 164, |
| 137, 254, 182, 248, 64, 201, 45, 209, 5, 147, 207, 210, 113, 162, 83, 225, |
| 9, 31, 15, 231, 115, 37, 58, 53, 24, 49, 197, 56, 120, 172, 48, 21, 214, |
| 129, 111, 11, 50, 187, 196, 34, 60, 103, 71, 144, 47, 203, 77, 80, 232, |
| 140, 222, 250, 206, 166, 247, 139, 249, 221, 72, 106, 27, 199, 117, 54, |
| 219, 135, 118, 40, 79, 41, 251, 46, 93, 212, 92, 233, 148, 28, 121, 63, |
| 123, 158, 105, 59, 29, 42, 143, 23, 0, 107, 176, 87, 104, 183, 156, 193, |
| 189, 90, 188, 65, 190, 17, 198, 7, 186, 161, 1, 124, 78, 125, 170, 133, |
| 174, 218, 67, 157, 75, 101, 89, 217, 62, 33, 141, 228, 25, 35, 91, 230, 4, |
| 2, 13, 73, 86, 167, 237, 84, 243, 44, 185, 66, 130, 110, 150, 142, 216, 88, |
| 112, 36, 224, 136, 202, 76, 94, 98, 175, 213 |
| }; |
| |
| bool skcms_ApproximatelyEqualProfiles(const skcms_ICCProfile* A, const skcms_ICCProfile* B) { |
| // For now this is the essentially the same strategy we use in test_only.c |
| // for our skcms_Transform() smoke tests: |
| // 1) transform A to XYZD50 |
| // 2) transform B to XYZD50 |
| // 3) return true if they're similar enough |
| // Our current criterion in 3) is maximum 1 bit error per XYZD50 byte. |
| |
| // Here are 252 of a random shuffle of all possible bytes. |
| // 252 is evenly divisible by 3 and 4. Only 192, 10, 241, and 43 are missing. |
| |
| if (A->data_color_space != B->data_color_space) { |
| return false; |
| } |
| |
| // Interpret as RGB_888 if data color space is RGB or GRAY, RGBA_8888 if CMYK. |
| skcms_PixelFormat fmt = skcms_PixelFormat_RGB_888; |
| size_t npixels = 84; |
| if (A->data_color_space == skcms_Signature_CMYK) { |
| fmt = skcms_PixelFormat_RGBA_8888; |
| npixels = 63; |
| } |
| |
| uint8_t dstA[252], |
| dstB[252]; |
| if (!skcms_Transform( |
| skcms_252_random_bytes, fmt, skcms_AlphaFormat_Unpremul, A, |
| dstA, skcms_PixelFormat_RGB_888, skcms_AlphaFormat_Unpremul, skcms_XYZD50_profile(), |
| npixels)) { |
| return false; |
| } |
| if (!skcms_Transform( |
| skcms_252_random_bytes, fmt, skcms_AlphaFormat_Unpremul, B, |
| dstB, skcms_PixelFormat_RGB_888, skcms_AlphaFormat_Unpremul, skcms_XYZD50_profile(), |
| npixels)) { |
| return false; |
| } |
| |
| for (size_t i = 0; i < 252; i++) { |
| if (abs((int)dstA[i] - (int)dstB[i]) > 1) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| bool skcms_TRCs_AreApproximateInverse(const skcms_ICCProfile* profile, |
| const skcms_TransferFunction* inv_tf) { |
| if (!profile || !profile->has_trc) { |
| return false; |
| } |
| |
| return skcms_AreApproximateInverses(&profile->trc[0], inv_tf) && |
| skcms_AreApproximateInverses(&profile->trc[1], inv_tf) && |
| skcms_AreApproximateInverses(&profile->trc[2], inv_tf); |
| } |
| |
| static bool is_zero_to_one(float x) { |
| return 0 <= x && x <= 1; |
| } |
| |
| bool skcms_PrimariesToXYZD50(float rx, float ry, |
| float gx, float gy, |
| float bx, float by, |
| float wx, float wy, |
| skcms_Matrix3x3* toXYZD50) { |
| if (!is_zero_to_one(rx) || !is_zero_to_one(ry) || |
| !is_zero_to_one(gx) || !is_zero_to_one(gy) || |
| !is_zero_to_one(bx) || !is_zero_to_one(by) || |
| !is_zero_to_one(wx) || !is_zero_to_one(wy) || |
| !toXYZD50) { |
| return false; |
| } |
| |
| // First, we need to convert xy values (primaries) to XYZ. |
| skcms_Matrix3x3 primaries = {{ |
| { rx, gx, bx }, |
| { ry, gy, by }, |
| { 1 - rx - ry, 1 - gx - gy, 1 - bx - by }, |
| }}; |
| skcms_Matrix3x3 primaries_inv; |
| if (!skcms_Matrix3x3_invert(&primaries, &primaries_inv)) { |
| return false; |
| } |
| |
| // Assumes that Y is 1.0f. |
| skcms_Vector3 wXYZ = { { wx / wy, 1, (1 - wx - wy) / wy } }; |
| skcms_Vector3 XYZ = skcms_MV_mul(&primaries_inv, &wXYZ); |
| |
| skcms_Matrix3x3 toXYZ = {{ |
| { XYZ.vals[0], 0, 0 }, |
| { 0, XYZ.vals[1], 0 }, |
| { 0, 0, XYZ.vals[2] }, |
| }}; |
| toXYZ = skcms_Matrix3x3_concat(&primaries, &toXYZ); |
| |
| // Now convert toXYZ matrix to toXYZD50. |
| skcms_Vector3 wXYZD50 = { { 0.96422f, 1.0f, 0.82521f } }; |
| |
| // Calculate the chromatic adaptation matrix. We will use the Bradford method, thus |
| // the matrices below. The Bradford method is used by Adobe and is widely considered |
| // to be the best. |
| skcms_Matrix3x3 xyz_to_lms = {{ |
| { 0.8951f, 0.2664f, -0.1614f }, |
| { -0.7502f, 1.7135f, 0.0367f }, |
| { 0.0389f, -0.0685f, 1.0296f }, |
| }}; |
| skcms_Matrix3x3 lms_to_xyz = {{ |
| { 0.9869929f, -0.1470543f, 0.1599627f }, |
| { 0.4323053f, 0.5183603f, 0.0492912f }, |
| { -0.0085287f, 0.0400428f, 0.9684867f }, |
| }}; |
| |
| skcms_Vector3 srcCone = skcms_MV_mul(&xyz_to_lms, &wXYZ); |
| skcms_Vector3 dstCone = skcms_MV_mul(&xyz_to_lms, &wXYZD50); |
| |
| skcms_Matrix3x3 DXtoD50 = {{ |
| { dstCone.vals[0] / srcCone.vals[0], 0, 0 }, |
| { 0, dstCone.vals[1] / srcCone.vals[1], 0 }, |
| { 0, 0, dstCone.vals[2] / srcCone.vals[2] }, |
| }}; |
| DXtoD50 = skcms_Matrix3x3_concat(&DXtoD50, &xyz_to_lms); |
| DXtoD50 = skcms_Matrix3x3_concat(&lms_to_xyz, &DXtoD50); |
| |
| *toXYZD50 = skcms_Matrix3x3_concat(&DXtoD50, &toXYZ); |
| return true; |
| } |
