/*
 * Copyright 2018 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifdef _MSC_VER
#define _CRT_SECURE_NO_WARNINGS
#endif

#include "skcms.h"
#include "src/LinearAlgebra.h"
#include "src/Macros.h"
#include "src/TransferFunction.h"
#include <math.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

#if defined(_MSC_VER)
    #define DEBUGBREAK __debugbreak
#elif defined(__clang__)
    #define DEBUGBREAK __builtin_debugtrap
#else
    #define DEBUGBREAK __builtin_trap
#endif

#define expect(cond)                                                                  \
    do {                                                                              \
        if (!(cond)) {                                                                \
            fprintf(stderr, "expect(" #cond ") failed at %s:%d\n",__FILE__,__LINE__); \
            fflush(stderr);   /* stderr is buffered on Windows. */                    \
            DEBUGBREAK();                                                             \
        }                                                                             \
    } while(false)

static void test_ICCProfile() {
    // Nothing works yet.  :)
    skcms_ICCProfile profile;

    const uint8_t buf[] = { 0x42 };
    expect(!skcms_Parse(buf, sizeof(buf), &profile));
}

static void test_FormatConversions() {
    // If we use a single skcms_ICCProfile, we should be able to use skcms_Transform()
    // to do skcms_PixelFormat conversions.
    skcms_ICCProfile profile;

    // We can interpret src as 85 RGB_888 pixels or 64 RGB_8888 pixels.
    uint8_t src[256],
            dst[85*4];
    for (int i = 0; i < 256; i++) {
        src[i] = (uint8_t)i;
    }

    // This should basically be a really complicated memcpy().
    expect(skcms_Transform(src, skcms_PixelFormat_RGBA_8888, &profile,
                           dst, skcms_PixelFormat_RGBA_8888, &profile,
                           64));
    for (int i = 0; i < 256; i++) {
        expect(dst[i] == i);
    }

    // We can do RGBA -> BGRA swaps two ways:
    expect(skcms_Transform(src, skcms_PixelFormat_RGBA_8888, &profile,
                           dst, skcms_PixelFormat_BGRA_8888, &profile,
                           64));
    for (int i = 0; i < 64; i++) {
        expect(dst[4*i+0] == 4*i+2);
        expect(dst[4*i+1] == 4*i+1);
        expect(dst[4*i+2] == 4*i+0);
        expect(dst[4*i+3] == 4*i+3);
    }
    expect(skcms_Transform(src, skcms_PixelFormat_BGRA_8888, &profile,
                           dst, skcms_PixelFormat_RGBA_8888, &profile,
                           64));
    for (int i = 0; i < 64; i++) {
        expect(dst[4*i+0] == 4*i+2);
        expect(dst[4*i+1] == 4*i+1);
        expect(dst[4*i+2] == 4*i+0);
        expect(dst[4*i+3] == 4*i+3);
    }

    // Let's convert RGB_888 to RGBA_8888...
    expect(skcms_Transform(src, skcms_PixelFormat_RGB_888  , &profile,
                           dst, skcms_PixelFormat_RGBA_8888, &profile,
                           85));
    for (int i = 0; i < 85; i++) {
        expect(dst[4*i+0] == 3*i+0);
        expect(dst[4*i+1] == 3*i+1);
        expect(dst[4*i+2] == 3*i+2);
        expect(dst[4*i+3] ==   255);
    }
    // ... and now all the variants of R-B swaps.
    expect(skcms_Transform(src, skcms_PixelFormat_BGR_888  , &profile,
                           dst, skcms_PixelFormat_BGRA_8888, &profile,
                           85));
    for (int i = 0; i < 85; i++) {
        expect(dst[4*i+0] == 3*i+0);
        expect(dst[4*i+1] == 3*i+1);
        expect(dst[4*i+2] == 3*i+2);
        expect(dst[4*i+3] ==   255);
    }
    expect(skcms_Transform(src, skcms_PixelFormat_BGR_888  , &profile,
                           dst, skcms_PixelFormat_RGBA_8888, &profile,
                           85));
    for (int i = 0; i < 85; i++) {
        expect(dst[4*i+0] == 3*i+2);
        expect(dst[4*i+1] == 3*i+1);
        expect(dst[4*i+2] == 3*i+0);
        expect(dst[4*i+3] ==   255);
    }
    expect(skcms_Transform(src, skcms_PixelFormat_RGB_888  , &profile,
                           dst, skcms_PixelFormat_BGRA_8888, &profile,
                           85));
    for (int i = 0; i < 85; i++) {
        expect(dst[4*i+0] == 3*i+2);
        expect(dst[4*i+1] == 3*i+1);
        expect(dst[4*i+2] == 3*i+0);
        expect(dst[4*i+3] ==   255);
    }

    // Let's test in-place transforms.
    // RGBA_8888 and RGB_888 aren't the same size, so we shouldn't allow this call.
    expect(!skcms_Transform(src, skcms_PixelFormat_RGB_888,   &profile,
                            src, skcms_PixelFormat_RGBA_8888, &profile,
                            85));

    // These two should work fine.
    expect(skcms_Transform(src, skcms_PixelFormat_BGRA_8888, &profile,
                           src, skcms_PixelFormat_RGBA_8888, &profile,
                           64));
    for (int i = 0; i < 64; i++) {
        expect(src[4*i+0] == 4*i+2);
        expect(src[4*i+1] == 4*i+1);
        expect(src[4*i+2] == 4*i+0);
        expect(src[4*i+3] == 4*i+3);
    }
    expect(skcms_Transform(src, skcms_PixelFormat_RGBA_8888, &profile,
                           src, skcms_PixelFormat_BGRA_8888, &profile,
                           64));
    for (int i = 0; i < 64; i++) {
        expect(src[4*i+0] == 4*i+0);
        expect(src[4*i+1] == 4*i+1);
        expect(src[4*i+2] == 4*i+2);
        expect(src[4*i+3] == 4*i+3);
    }

    uint32_t _8888[3] = { 0x03020100, 0x07060504, 0x0b0a0908 };
    uint8_t _888[9];
    expect(skcms_Transform(_8888, skcms_PixelFormat_RGBA_8888, &profile,
                           _888 , skcms_PixelFormat_RGB_888  , &profile,
                           3));
    expect(_888[0] == 0 && _888[1] == 1 && _888[2] ==  2);
    expect(_888[3] == 4 && _888[4] == 5 && _888[5] ==  6);
    expect(_888[6] == 8 && _888[7] == 9 && _888[8] == 10);
}

static void test_FormatConversions_565() {
    // If we use a single skcms_ICCProfile, we should be able to use skcms_Transform()
    // to do skcms_PixelFormat conversions.
    skcms_ICCProfile profile;

    // This should hit all the unique values of each lane of 565.
    uint16_t src[64];
    for (int i = 0; i < 64; i++) {
        src[i] = (uint16_t)( (i/2) <<  0 )
               | (uint16_t)( (i/1) <<  5 )
               | (uint16_t)( (i/2) << 11 );
    }
    expect(src[ 0] == 0x0000);
    expect(src[31] == 0x7bef);
    expect(src[63] == 0xffff);

    uint32_t dst[64];
    expect(skcms_Transform(src, skcms_PixelFormat_RGB_565,   &profile,
                           dst, skcms_PixelFormat_RGBA_8888, &profile,
                           64));
    // We'll just spot check these results a bit.
    for (int i = 0; i < 64; i++) {
        expect((dst[i] >> 24) == 255);  // All opaque.
    }
    expect(dst[ 0] == 0xff000000);  // 0 -> 0
    expect(dst[20] == 0xff525152);  // (10/31) ≈ (82/255) and (20/63) ≈ (81/255)
    expect(dst[62] == 0xfffffbff);  // (31/31) == (255/255) and (62/63) ≈ (251/255)
    expect(dst[63] == 0xffffffff);  // 1 -> 1

    // Let's convert back the other way.
    uint16_t back[64];
    expect(skcms_Transform(dst , skcms_PixelFormat_RGBA_8888, &profile,
                           back, skcms_PixelFormat_RGB_565  , &profile,
                           64));
    for (int i = 0; i < 64; i++) {
        expect(src[i] == back[i]);
    }
}

static void test_FormatConversions_16161616() {
    skcms_ICCProfile profile;

    // We want to hit each 16-bit value, 4 per each of 16384 pixels.
    uint64_t* src = malloc(8 * 16384);
    for (int i = 0; i < 16384; i++) {
        src[i] = (uint64_t)(4*i + 0) <<  0
               | (uint64_t)(4*i + 1) << 16
               | (uint64_t)(4*i + 2) << 32
               | (uint64_t)(4*i + 3) << 48;
    }
    expect(src[    0] == 0x0003000200010000);
    expect(src[ 8127] == 0x7eff7efe7efd7efc);  // This should demonstrate interesting rounding.
    expect(src[16383] == 0xfffffffefffdfffc);

    uint32_t* dst = malloc(4 * 16384);
    expect(skcms_Transform(src, skcms_PixelFormat_RGBA_16161616, &profile,
                           dst, skcms_PixelFormat_RGBA_8888    , &profile,
                           16384));

    // skcms_Transform() will treat src as holding big-endian 16-bit values,
    // so the low lanes are actually the most significant byte, and the high least.

    expect(dst[    0] == 0x03020100);
    expect(dst[ 8127] == 0xfefefdfc);  // 0x7eff rounds down to 0xfe, 0x7efe rounds up to 0xfe.
    expect(dst[16383] == 0xfffefdfc);

    // We've lost precision when transforming to 8-bit, so these won't quite round-trip.
    // Instead we should see the 8-bit dst value byte-doubled, as 65535/255 = 257 = 0x0101.
    uint64_t* back = malloc(8 * 16384);
    expect(skcms_Transform(dst , skcms_PixelFormat_RGBA_8888    , &profile,
                           back, skcms_PixelFormat_RGBA_16161616, &profile,
                           16384));
    for (int i = 0; i < 16384; i++) {
        expect( ((back[i] >>  0) & 0xffff) == ((dst[i] >>  0) & 0xff) * 0x0101);
        expect( ((back[i] >> 16) & 0xffff) == ((dst[i] >>  8) & 0xff) * 0x0101);
        expect( ((back[i] >> 32) & 0xffff) == ((dst[i] >> 16) & 0xff) * 0x0101);
        expect( ((back[i] >> 48) & 0xffff) == ((dst[i] >> 24) & 0xff) * 0x0101);
    }

    free(src);
    free(dst);
    free(back);
}

static void test_FormatConversions_161616() {
    skcms_ICCProfile profile;

    // We'll test the same cases as the _16161616() test, as if they were 4 RGB pixels.
    uint16_t src[] = { 0x0000, 0x0001, 0x0002,
                       0x0003, 0x7efc, 0x7efd,
                       0x7efe, 0x7eff, 0xfffc,
                       0xfffd, 0xfffe, 0xffff };
    uint32_t dst[4];
    expect(skcms_Transform(src, skcms_PixelFormat_RGB_161616, &profile,
                           dst, skcms_PixelFormat_RGBA_8888 , &profile,
                           4));

    expect(dst[0] == 0xff020100);
    expect(dst[1] == 0xfffdfc03);
    expect(dst[2] == 0xfffcfefe);
    expect(dst[3] == 0xfffffefd);

    // We've lost precision when transforming to 8-bit, so these won't quite round-trip.
    // Instead we should see the most signficant (low) byte doubled, as 65535/255 = 257 = 0x0101.
    uint16_t back[12];
    expect(skcms_Transform(dst , skcms_PixelFormat_RGBA_8888 , &profile,
                           back, skcms_PixelFormat_RGB_161616, &profile,
                           4));
    for (int i = 0; i < 12; i++) {
        expect(back[0] == (src[0] & 0xff) * 0x0101);
    }
}

static void test_FormatConversions_101010() {
    skcms_ICCProfile profile;

    uint32_t src = (uint32_t)1023 <<  0    // 1.0.
                 | (uint32_t) 511 << 10    // About 1/2.
                 | (uint32_t)   4 << 20    // Smallest 10-bit channel that's non-zero in 8-bit.
                 | (uint32_t)   1 << 30;   // 1/3, smallest non-zero alpha.
    uint32_t dst;
    expect(skcms_Transform(&src, skcms_PixelFormat_RGBA_1010102, &profile,
                           &dst, skcms_PixelFormat_RGBA_8888   , &profile,
                           1));
    expect(dst == 0x55017fff);

    // Same as above, but we'll ignore the 1/3 alpha and fill in 1.0.
    expect(skcms_Transform(&src, skcms_PixelFormat_RGB_101010x, &profile,
                           &dst, skcms_PixelFormat_RGBA_8888  , &profile,
                           1));
    expect(dst == 0xff017fff);

    // Converting 101010x <-> 1010102 will force opaque in either direction.
    expect(skcms_Transform(&src, skcms_PixelFormat_RGBA_1010102, &profile,
                           &dst, skcms_PixelFormat_RGB_101010x , &profile,
                           1));
    expect(dst == ( (uint32_t)1023 <<  0
                  | (uint32_t) 511 << 10
                  | (uint32_t)   4 << 20
                  | (uint32_t)   3 << 30));
    expect(skcms_Transform(&src, skcms_PixelFormat_RGB_101010x , &profile,
                           &dst, skcms_PixelFormat_RGBA_1010102, &profile,
                           1));
    expect(dst == ( (uint32_t)1023 <<  0
                  | (uint32_t) 511 << 10
                  | (uint32_t)   4 << 20
                  | (uint32_t)   3 << 30));
}

static void test_FormatConversions_half() {
    skcms_ICCProfile profile;

    uint16_t src[] = {
        0x3c00,  // 1.0
        0x3800,  // 0.5
        0x1805,  // Should round up to 0x01
        0x1804,  // Should round down to 0x00
        0x4000,  // 2.0
        0x03ff,  // A denorm, may be flushed to zero.
        0x83ff,  // A negative denorm, may be flushed to zero.
        0xbc00,  // -1.0
    };

    uint32_t dst[2];
    expect(skcms_Transform(&src, skcms_PixelFormat_RGBA_hhhh, &profile,
                           &dst, skcms_PixelFormat_RGBA_8888, &profile,
                           2));
    expect(dst[0] == 0x000180ff);
    expect(dst[1] == 0x000000ff);  // Notice we've clamped 2.0 to 0xff and -1.0 to 0x00.

    expect(skcms_Transform(&src, skcms_PixelFormat_RGB_hhh,   &profile,
                           &dst, skcms_PixelFormat_RGBA_8888, &profile,
                           2));
    expect(dst[0] == 0xff0180ff);
    expect(dst[1] == 0xff00ff00);  // Remember, this corresponds to src[3-5].

    float fdst[8];
    expect(skcms_Transform( &src, skcms_PixelFormat_RGBA_hhhh, &profile,
                           &fdst, skcms_PixelFormat_RGBA_ffff, &profile,
                           2));
    expect(fdst[0] ==  1.0f);
    expect(fdst[1] ==  0.5f);
    expect(fdst[2] > 1/510.0f);
    expect(fdst[3] < 1/510.0f);
    expect(fdst[4] ==  2.0f);
    expect(fdst[5] == +0.00006097555f || fdst[5] == 0.0f);  // may have been flushed to zero
    expect(fdst[6] == -0.00006097555f || fdst[6] == 0.0f);
    expect(fdst[7] == -1.0f);

    // Now convert back, first to RGBA halfs, then RGB halfs.
    uint16_t back[8];
    expect(skcms_Transform(&fdst, skcms_PixelFormat_RGBA_ffff, &profile,
                           &back, skcms_PixelFormat_RGBA_hhhh, &profile,
                           2));
    expect(back[0] == src[0]);
    expect(back[1] == src[1]);
    expect(back[2] == src[2]);
    expect(back[3] == src[3]);
    expect(back[4] == src[4]);
    expect(back[5] == src[5] || back[5] == 0x0000);
    expect(back[6] == src[6] || back[6] == 0x0000);
    expect(back[7] == src[7]);

    expect(skcms_Transform(&fdst, skcms_PixelFormat_RGBA_ffff, &profile,
                           &back, skcms_PixelFormat_RGB_hhh  , &profile,
                           2));
    expect(back[0] == src[0]);
    expect(back[1] == src[1]);
    expect(back[2] == src[2]);
    expect(back[3] == src[4]);
    expect(back[4] == src[5] || back[4] == 0x0000);
    expect(back[5] == src[6] || back[5] == 0x0000);
}

static void test_FormatConversions_float() {
    skcms_ICCProfile profile;

    float src[] = { 1.0f, 0.5f, 1/255.0f, 1/512.0f };

    uint32_t dst;
    expect(skcms_Transform(&src, skcms_PixelFormat_RGBA_ffff, &profile,
                           &dst, skcms_PixelFormat_RGBA_8888, &profile,
                           1));
    expect(dst == 0x000180ff);

    // Same as above, but we'll ignore the 1/512 alpha and fill in 1.0.
    expect(skcms_Transform(&src, skcms_PixelFormat_RGB_fff,   &profile,
                           &dst, skcms_PixelFormat_RGBA_8888, &profile,
                           1));
    expect(dst == 0xff0180ff);

    // Let's make sure each byte converts to the float we expect.
    uint32_t bytes[64];
    float   fdst[4*64];
    for (int i = 0; i < 64; i++) {
        bytes[i] = 0x03020100 + 0x04040404 * (uint32_t)i;
    }
    expect(skcms_Transform(&bytes, skcms_PixelFormat_RGBA_8888, &profile,
                            &fdst, skcms_PixelFormat_RGBA_ffff, &profile,
                           64));
    for (int i = 0; i < 256; i++) {
        expect(fdst[i] == i*(1/255.0f));
    }

    float ffff[16] = { 0,1,2,3, 4,5,6,7, 8,9,10,11, 12,13,14,15 };
    float  fff[12] = { 0,0,0, 0,0,0, 0,0,0, 0,0,0};
    expect(skcms_Transform(ffff, skcms_PixelFormat_RGBA_ffff, &profile,
                           fff , skcms_PixelFormat_RGB_fff  , &profile,
                           1));
    expect(fff[0] == 0); expect(fff[1] == 1); expect(fff[2] == 2);

    expect(skcms_Transform(ffff, skcms_PixelFormat_RGBA_ffff, &profile,
                           fff , skcms_PixelFormat_RGB_fff  , &profile,
                           4));
    expect(fff[0] ==  0); expect(fff[ 1] ==  1); expect(fff[ 2] ==  2);
    expect(fff[3] ==  4); expect(fff[ 4] ==  5); expect(fff[ 5] ==  6);
    expect(fff[6] ==  8); expect(fff[ 7] ==  9); expect(fff[ 8] == 10);
    expect(fff[9] == 12); expect(fff[10] == 13); expect(fff[11] == 14);
}

static const skcms_TransferFunction srgb_transfer_fn =
    { 2.4f, 1 / 1.055f, 0.055f / 1.055f, 1 / 12.92f, 0.04045f, 0.0f, 0.0f };
static const skcms_TransferFunction kodak_transfer_fn =
    { 2.404834f, 0.945568f, 0.052557f, 0.151814f, 0.133333f, 0.004353f, 0.0f };
static const skcms_TransferFunction gamma_1_8_transfer_fn =
    { 1.8f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f };
static const skcms_TransferFunction gamma_2_2_transfer_fn =
    { 2.2f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f };
static const skcms_TransferFunction gamma_2_4_transfer_fn =
    { 2.4f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f };
static const skcms_TransferFunction gamma_2_8_transfer_fn =
    { 2.8f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f };
static const skcms_TransferFunction bt_709_transfer_fn =
    { 1 / 0.45f, 1 / 1.099f, 0.099f / 1.099f, 1 / 4.5f, 0.081f, 0.0f, 0.0f };
static const skcms_TransferFunction smpte_240m_transfer_fn =
    { 1 / 0.45f, 1 / 1.1115f, 0.1115f / 1.1115f, 0.25f, 0.0913f, 0.0f, 0.0f };
// These are two different ways to represent the linear (identity) transfer function
static const skcms_TransferFunction gamma_1_transfer_fn =
    { 1.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f };
static const skcms_TransferFunction linear_transfer_fn =
    { 0.0f, 1.0f, 0.0f, 1.0f, 2.0f, 0.0f, 0.0f };

static const skcms_Matrix3x3 srgb_to_xyz  = { { { 0.4360657f, 0.3851471f, 0.1430664f },
                                                { 0.2224884f, 0.7168732f, 0.0606079f },
                                                { 0.0139160f, 0.0970764f, 0.7140961f } } };

static const skcms_Matrix3x3 sgbr_to_xyz  = { { { 0.3851471f, 0.1430664f, 0.4360657f },
                                                { 0.7168732f, 0.0606079f, 0.2224884f },
                                                { 0.0970764f, 0.7140961f, 0.0139160f } } };

static const skcms_Matrix3x3 srgb_lcms_to_xyz  = { { { 0.4358521f, 0.3853302f, 0.1430206f },
                                                     { 0.2223816f, 0.7170410f, 0.0605927f },
                                                     { 0.0139160f, 0.0971375f, 0.7138367f } } };

static const skcms_Matrix3x3 kodak_to_xyz  = { { { 0.4376373f, 0.3884125f, 0.1424103f },
                                                 { 0.2149506f, 0.7129059f, 0.0721283f, },
                                                 { 0.0112610f, 0.0807190f, 0.7258759f } } };

static const skcms_Matrix3x3 adobe_to_xyz = { { { 0.6097412f, 0.2052765f, 0.1491852f },
                                                { 0.3111115f, 0.6256714f, 0.0632172f },
                                                { 0.0194702f, 0.0608673f, 0.7445679f } } };

static const skcms_Matrix3x3 p3_to_xyz    = { { { 0.5151215f, 0.2919769f, 0.1571045f },
                                                { 0.2411957f, 0.6922455f, 0.0665741f },
                                                { -0.0010376f, 0.0418854f, 0.7840729f } } };

static const skcms_Matrix3x3 apple_lcd_to_xyz = { { { 0.4443359f, 0.3794403f, 0.1404114f },
                                                    { 0.2247620f, 0.7261658f, 0.0490723f },
                                                    { 0.0054779f, 0.0779724f, 0.7414551f } } };

static const skcms_Matrix3x3 gen_rgb_to_xyz = { { { 0.4542999f, 0.3533478f, 0.1566467f },
                                                  { 0.2419128f, 0.6736298f, 0.0844574f },
                                                  { 0.0148926f, 0.0906372f, 0.7195740f } } };

static const skcms_Matrix3x3 hd709_to_xyz = { { { 0.3589630f, 0.4463501f, 0.1588898f },
                                                { 0.1959229f, 0.7428436f, 0.0612335f },
                                                { 0.0096741f, 0.0435181f, 0.7717133f } } };

static const skcms_Matrix3x3 mm_hard_to_xyz = { { { 0.9642029f, 0.0000000f, 0.9642029f },
                                                  { 1.0000000f, 0.0000000f, 1.0000000f },
                                                  { 0.8249054f, 0.0000000f, 0.8249054f } } };

static const skcms_Matrix3x3 ph1_to_xyz = { { { 0.6479034f, 0.3573608f, 0.1564178f },
                                              { 0.3829193f, 1.1097260f, 0.0000000f },
                                              { 0.0832672f, 0.6792755f, 0.5234222f } } };

typedef struct {
    const char*                   filename;
    bool                          expect_parse;
    const skcms_TransferFunction* expect_exact_tf;
    const skcms_TransferFunction* expect_approx_tf;
    const skcms_Matrix3x3*        expect_xyz;
} ProfileTestCase;

static const ProfileTestCase profile_test_cases[] = {
    // iccMAX profiles that we can't parse at all
    { "profiles/color.org/sRGB_D65_colorimetric.icc",  false, NULL, NULL, NULL },
    { "profiles/color.org/sRGB_D65_MAT.icc",           false, NULL, NULL, NULL },
    { "profiles/color.org/sRGB_ISO22028.icc",          false, NULL, NULL, NULL },

    // V2 or V4 profiles that only include A2B/B2A tags (no TRC or XYZ)
    { "profiles/color.org/sRGB_ICC_v4_Appearance.icc", true, NULL, NULL, NULL },
    { "profiles/color.org/sRGB_v4_ICC_preference.icc", true, NULL, NULL, NULL },
    { "profiles/color.org/Upper_Left.icc",             true, NULL, NULL, NULL },
    { "profiles/color.org/Upper_Right.icc",            true, NULL, NULL, NULL },
    { "profiles/misc/Apple_Wide_Color.icc",            true, NULL, NULL, NULL },
    { "profiles/misc/Coated_FOGRA39_CMYK.icc",         true, NULL, NULL, NULL },
    { "profiles/misc/ColorGATE_Sihl_PhotoPaper.icc",   true, NULL, NULL, NULL }, // Has kTRC. Broken tag table, but A2B0 parses okay
    { "profiles/misc/ColorLogic_ISO_Coated_CMYK.icc",  true, NULL, NULL, NULL }, // Has kTRC.
    { "profiles/misc/Japan_Color_2001_Coated.icc",     true, NULL, NULL, NULL },
    { "profiles/misc/Lexmark_X110.icc",                true, NULL, NULL, NULL },
    { "profiles/misc/MartiMaria_browsertest_A2B.icc",  true, NULL, NULL, NULL },
    { "profiles/misc/PrintOpen_ISO_Coated_CMYK.icc",   true, NULL, NULL, NULL }, // Has kTRC.
    { "profiles/misc/sRGB_ICC_v4_beta.icc",            true, NULL, NULL, NULL },
    { "profiles/misc/SWOP_Coated_20_GCR_CMYK.icc",     true, NULL, NULL, NULL },
    { "profiles/misc/US_Web_Coated_SWOP_CMYK.icc",     true, NULL, NULL, NULL },
    { "profiles/misc/XRite_GRACol7_340_CMYK.icc",      true, NULL, NULL, NULL },

    // V2 monochrome output profiles that include kTRC but no A2B
    { "profiles/misc/Dot_Gain_20_Grayscale.icc",       true, NULL, NULL, NULL }, // kTRC table
    { "profiles/misc/Gray_Gamma_22.icc",               true, NULL, NULL, NULL }, // kTRC gamma

    // V4 profiles with parametric TRC curves and XYZ
    { "profiles/mobile/Display_P3_parametric.icc",     true, &srgb_transfer_fn, NULL, &p3_to_xyz },
    { "profiles/mobile/sRGB_parametric.icc",           true, &srgb_transfer_fn, NULL, &srgb_to_xyz },
    { "profiles/mobile/iPhone7p.icc",                  true, &srgb_transfer_fn, NULL, &p3_to_xyz },
    { "profiles/misc/sRGB_lcms.icc",                   true, &srgb_transfer_fn, NULL, &srgb_lcms_to_xyz },

    // V4 profiles with LUT TRC curves and XYZ
    { "profiles/mobile/Display_P3_LUT.icc",            true, NULL, &srgb_transfer_fn, &p3_to_xyz },
    { "profiles/mobile/sRGB_LUT.icc",                  true, NULL, &srgb_transfer_fn, &srgb_to_xyz },

    // V2 profiles with gamma TRC and XYZ
    { "profiles/color.org/Lower_Left.icc",             true, &gamma_2_2_transfer_fn, NULL, &sgbr_to_xyz },
    { "profiles/color.org/Lower_Right.icc",            true, &gamma_2_2_transfer_fn, NULL, &adobe_to_xyz },
    { "profiles/misc/AdobeRGB.icc",                    true, &gamma_2_2_transfer_fn, NULL, &adobe_to_xyz },
    { "profiles/misc/Color_Spin_Gamma_18.icc",         true, &gamma_1_8_transfer_fn, NULL, &sgbr_to_xyz },
    { "profiles/misc/Generic_RGB_Gamma_18.icc",        true, &gamma_1_8_transfer_fn, NULL, &gen_rgb_to_xyz },

    // V2 profiles with LUT TRC and XYZ
    { "profiles/color.org/sRGB2014.icc",               true, NULL, &srgb_transfer_fn, &srgb_to_xyz },
    { "profiles/sRGB_Facebook.icc",                    true, NULL, &srgb_transfer_fn, &srgb_to_xyz },
    { "profiles/misc/Apple_Color_LCD.icc",             true, NULL, &srgb_transfer_fn, &apple_lcd_to_xyz },
    { "profiles/misc/HD_709.icc",                      true, NULL, &srgb_transfer_fn, &hd709_to_xyz},
    { "profiles/misc/sRGB_black_scaled.icc",           true, NULL, &srgb_transfer_fn, &srgb_to_xyz },
    { "profiles/misc/sRGB_HP.icc",                     true, NULL, &srgb_transfer_fn, &srgb_to_xyz },
    { "profiles/misc/sRGB_HP_2.icc",                   true, NULL, &srgb_transfer_fn, &srgb_to_xyz },

    // Hard test profile. Non-invertible XYZ, three separate tables that fail to approximate
    { "profiles/misc/MartiMaria_browsertest_HARD.icc", true, NULL, NULL, &mm_hard_to_xyz },

    // Camera profile with three separate tables that fail to approximate
    { "profiles/misc/Phase_One_P25.icc",               true, NULL, NULL, &ph1_to_xyz },

    // Profile claims to be sRGB, but seems quite different
    { "profiles/misc/Kodak_sRGB.icc",                  true, NULL, &kodak_transfer_fn, &kodak_to_xyz },

    // fuzzer generated profiles that found parsing bugs

    // Bad tag table data - these should not parse
    { "profiles/fuzz/last_tag_too_small.icc",          false, NULL, NULL, NULL }, // skia:7592
    { "profiles/fuzz/named_tag_too_small.icc",         false, NULL, NULL, NULL }, // skia:7592

    // These parse but have trouble afterward.
    { "profiles/fuzz/curv_size_overflow.icc",          true, NULL, NULL, NULL }, // skia:7593
    { "profiles/fuzz/truncated_curv_tag.icc",          true, NULL, NULL, NULL }, // oss-fuzz:6103
    { "profiles/fuzz/zero_a.icc",                      true, NULL, NULL, NULL }, // oss-fuzz:????
    { "profiles/fuzz/a2b_too_many_input_channels.icc", true, NULL, NULL, NULL }, // oss-fuzz:6521
};

static void load_file(const char* filename, void** buf, size_t* len) {
    FILE* fp = fopen(filename, "rb");
    expect(fp);

    expect(fseek(fp, 0L, SEEK_END) == 0);
    long size = ftell(fp);
    expect(size > 0);
    *len = (size_t)size;
    rewind(fp);

    *buf = malloc(*len);
    expect(*buf);

    size_t bytes_read = fread(*buf, 1, *len, fp);
    expect(bytes_read == *len);
}

static void check_transfer_function(skcms_TransferFunction fn_a,
                                    skcms_TransferFunction fn_b,
                                    float tol) {
    expect(fabsf(fn_a.g - fn_b.g) < tol);
    expect(fabsf(fn_a.a - fn_b.a) < tol);
    expect(fabsf(fn_a.b - fn_b.b) < tol);
    expect(fabsf(fn_a.c - fn_b.c) < tol);
    expect(fabsf(fn_a.d - fn_b.d) < tol);
    expect(fabsf(fn_a.e - fn_b.e) < tol);
    expect(fabsf(fn_a.f - fn_b.f) < tol);
}

static void check_roundtrip_transfer_functions(const skcms_TransferFunction* fwd,
                                               const skcms_TransferFunction* rev,
                                               float tol) {
    for (int i = 0; i < 256; ++i) {
        float t = i / 255.0f;
        float x = skcms_TransferFunction_eval(rev, skcms_TransferFunction_eval(fwd, t));
        expect((int)(x * 255.0f + 0.5f) == i);
        expect(fabsf(x - t) < tol);
    }
}

static void test_Parse() {
    const int test_cases_count = ARRAY_COUNT(profile_test_cases);
    for (int i = 0; i < test_cases_count; ++i) {
        const ProfileTestCase* test = profile_test_cases + i;

        // Make sure the test parameters are internally consistent
        expect(test->expect_parse || !test->expect_exact_tf);
        expect(test->expect_parse || !test->expect_approx_tf);
        expect(test->expect_parse || !test->expect_xyz);
        expect(!(test->expect_exact_tf && test->expect_approx_tf));

        void* buf = NULL;
        size_t len = 0;
        load_file(test->filename, &buf, &len);
        skcms_ICCProfile profile;
        bool result = skcms_Parse(buf, len, &profile);
        expect(result == test->expect_parse);

        if (!result) {
            free(buf);
            continue;
        }

        expect(profile.has_tf == !!test->expect_exact_tf);

        skcms_TransferFunction approx_tf;
        float max_error;
        bool approx_tf_result = skcms_ApproximateTransferFunction(&profile, &approx_tf,
                                                                             &max_error);
        expect(approx_tf_result == !!test->expect_approx_tf);

        if (profile.has_tf) {
            // V2 'curv' gamma values are 8.8 fixed point, so the maximum error is the value we
            // use here: 0.5 / 256 (~= 0.002)
            // V4 'para' curves are 1.15.16 fixed point, and should be precise to 5 digits, but
            // vendors sometimes round strangely when writing values. Regardless, all of our test
            // profiles are within 0.001, except for the odd version of sRGB used in the iPhone
            // profile. It has a D value of .039 (2556 / 64k) rather than .04045 (2651 / 64k).
            check_transfer_function(*test->expect_exact_tf, profile.tf, 0.5f / 256.0f);
        }

        if (approx_tf_result) {
            // Our approximate curves can vary pretty significantly from the reference curves,
            // so this needs to be fairly tolerant. The more important thing is how the overall
            // curve behaves - which is tested with the byte round-tripping below.
            check_transfer_function(*test->expect_approx_tf, approx_tf, 0.01f);

            // For this check, run every byte value through the forward version of one TF, and
            // the inverse of the other, and make sure it round-trips (using both combinations).
            skcms_TransferFunction approx_inverse_tf;
            skcms_TransferFunction expect_inverse_tf;
            expect(skcms_TransferFunction_invert(&approx_tf, &approx_inverse_tf));
            expect(skcms_TransferFunction_invert(test->expect_approx_tf, &expect_inverse_tf));

            // This function verifies that all bytes round-trip perfectly, but also takes a
            // tolerance to further limit the error after round-trip. We can currently get this
            // within ~30% of a byte (0.0011).
            check_roundtrip_transfer_functions(&approx_tf, &expect_inverse_tf, 0.02f);
            check_roundtrip_transfer_functions(test->expect_approx_tf, &approx_inverse_tf, 0.02f);
        }

        expect(profile.has_toXYZD50 == !!test->expect_xyz);

        if (profile.has_toXYZD50) {
            // XYZ values are 1.15.16 fixed point, but the precise values used by vendors vary
            // quite a bit, especially depending on their implementation of D50 adaptation.
            // This is still a pretty tight tolerance, and all of our test profiles pass.
            const float kXYZ_Tol = 0.0002f;
            for (int r = 0; r < 3; ++r) {
                for (int c = 0; c < 3; ++c) {
                    expect( fabsf( profile.toXYZD50.vals[r][c] -
                                  test->expect_xyz->vals[r][c]) < kXYZ_Tol );
                }
            }
        }

        free(buf);
    }
}

static void test_TransferFunction_approximate() {
    const skcms_TransferFunction* transfer_fns[] = {
        &gamma_2_2_transfer_fn,
        &gamma_2_4_transfer_fn,
        &gamma_2_8_transfer_fn,
        &srgb_transfer_fn,
        &smpte_240m_transfer_fn,
        &bt_709_transfer_fn,
        &gamma_1_transfer_fn,
        &linear_transfer_fn,
    };
    const int num_transfer_fns = ARRAY_COUNT(transfer_fns);

    int table_sizes[] = { 512, 256, 128, 64, 16, 11, 8, 7, 6, 5, 4 };
    const int num_table_sizes = ARRAY_COUNT(table_sizes);

    for (int ts = 0; ts < num_table_sizes; ++ts) {
        float* x = malloc((size_t)table_sizes[ts] * sizeof(float));
        for (int i = 0; i < table_sizes[ts]; ++i) {
            x[i] = (float)i / (table_sizes[ts] - 1);
        }

        float* t = malloc((size_t)table_sizes[ts] * sizeof(float));
        for (int tf = 0; tf < num_transfer_fns; ++tf) {
            for (int i = 0; i < table_sizes[ts]; ++i) {
                t[i] = skcms_TransferFunction_eval(transfer_fns[tf], x[i]);
            }

            skcms_TransferFunction fn_approx;
            float max_error;
            expect(skcms_TransferFunction_approximate(&fn_approx, x, t, table_sizes[ts],
                                                      &max_error));

            expect(max_error < 3.f / 256.f);
        }

        free(x);
        free(t);
    }
}

static void test_TransferFunction_approximate_clamped() {
    // These data represent a transfer function that is clamped at the high
    // end of its domain. It comes from the color profile attached to
    // https://crbug.com/750459
    float t[256] = {
        0.000000f, 0.000305f, 0.000610f, 0.000916f, 0.001221f, 0.001511f,
        0.001816f, 0.002121f, 0.002426f, 0.002731f, 0.003037f, 0.003601f,
        0.003937f, 0.004303f, 0.004685f, 0.005081f, 0.005509f, 0.005951f,
        0.006409f, 0.006882f, 0.007385f, 0.007904f, 0.008438f, 0.009003f,
        0.009583f, 0.010193f, 0.010819f, 0.011460f, 0.012131f, 0.012818f,
        0.013535f, 0.014267f, 0.015030f, 0.015808f, 0.016617f, 0.017456f,
        0.018296f, 0.019181f, 0.020081f, 0.021012f, 0.021958f, 0.022934f,
        0.023926f, 0.024949f, 0.026001f, 0.027070f, 0.028168f, 0.029297f,
        0.030442f, 0.031617f, 0.032822f, 0.034058f, 0.035309f, 0.036591f,
        0.037903f, 0.039231f, 0.040604f, 0.041993f, 0.043412f, 0.044846f,
        0.046326f, 0.047822f, 0.049348f, 0.050904f, 0.052491f, 0.054108f,
        0.055756f, 0.057420f, 0.059113f, 0.060853f, 0.062608f, 0.064393f,
        0.066209f, 0.068055f, 0.069932f, 0.071839f, 0.073762f, 0.075731f,
        0.077729f, 0.079759f, 0.081804f, 0.083894f, 0.086015f, 0.088167f,
        0.090333f, 0.092546f, 0.094789f, 0.097063f, 0.099367f, 0.101701f,
        0.104067f, 0.106477f, 0.108904f, 0.111360f, 0.113863f, 0.116381f,
        0.118944f, 0.121538f, 0.124163f, 0.126818f, 0.129519f, 0.132235f,
        0.134997f, 0.137789f, 0.140612f, 0.143465f, 0.146365f, 0.149279f,
        0.152239f, 0.155230f, 0.158267f, 0.161318f, 0.164416f, 0.167544f,
        0.170718f, 0.173907f, 0.177142f, 0.180407f, 0.183719f, 0.187045f,
        0.190433f, 0.193835f, 0.197284f, 0.200763f, 0.204273f, 0.207813f,
        0.211398f, 0.215030f, 0.218692f, 0.222385f, 0.226108f, 0.229877f,
        0.233677f, 0.237522f, 0.241382f, 0.245304f, 0.249256f, 0.253239f,
        0.257252f, 0.261311f, 0.265415f, 0.269551f, 0.273716f, 0.277928f,
        0.282170f, 0.286458f, 0.290776f, 0.295140f, 0.299535f, 0.303975f,
        0.308446f, 0.312947f, 0.317494f, 0.322087f, 0.326711f, 0.331380f,
        0.336080f, 0.340826f, 0.345602f, 0.350423f, 0.355291f, 0.360174f,
        0.365118f, 0.370092f, 0.375113f, 0.380163f, 0.385260f, 0.390387f,
        0.395560f, 0.400778f, 0.406027f, 0.411322f, 0.416663f, 0.422034f,
        0.427451f, 0.432898f, 0.438392f, 0.443931f, 0.449500f, 0.455116f,
        0.460777f, 0.466468f, 0.472221f, 0.477989f, 0.483818f, 0.489677f,
        0.495583f, 0.501518f, 0.507500f, 0.513527f, 0.519600f, 0.525719f,
        0.531868f, 0.538064f, 0.544289f, 0.550576f, 0.556893f, 0.563256f,
        0.569650f, 0.576104f, 0.582589f, 0.589120f, 0.595697f, 0.602304f,
        0.608972f, 0.615671f, 0.622415f, 0.629206f, 0.636027f, 0.642908f,
        0.649821f, 0.656779f, 0.663783f, 0.670832f, 0.677913f, 0.685054f,
        0.692226f, 0.699443f, 0.706706f, 0.714015f, 0.721370f, 0.728771f,
        0.736202f, 0.743694f, 0.751217f, 0.758785f, 0.766400f, 0.774060f,
        0.781765f, 0.789517f, 0.797314f, 0.805158f, 0.813031f, 0.820966f,
        0.828946f, 0.836957f, 0.845029f, 0.853132f, 0.861280f, 0.869490f,
        0.877729f, 0.886015f, 0.894362f, 0.902739f, 0.911162f, 0.919631f,
        0.928161f, 0.936721f, 0.945327f, 0.953994f, 0.962692f, 0.971435f,
        0.980240f, 0.989075f, 0.997955f, 1.000000f,
    };
    float x[256];
    for (int i = 0; i < 256; ++i) {
        x[i] = i / 255.f;
    }

    skcms_TransferFunction fn_approx;
    float max_error;
    expect(skcms_TransferFunction_approximate(&fn_approx, x, t, 256, &max_error));

    // The approximation should be nearly exact.
    expect(max_error < 1 / 4096.f);
}

static void test_TransferFunction_approximate_badMatch() {
    const int kTableSize = 512;
    const skcms_TransferFunction* transfer_fns[3] = {
        &srgb_transfer_fn,
        &gamma_2_2_transfer_fn,
        &bt_709_transfer_fn,
    };

    float* x = malloc(kTableSize * 3 * sizeof(float));
    float* t = malloc(kTableSize * 3 * sizeof(float));

    // Create a table containing each of these functions
    for (int tf = 0; tf < 3; ++tf) {
        for (int i = 0; i < kTableSize; ++i) {
            x[kTableSize * tf + i] = i / (kTableSize - 1.f);
            t[kTableSize * tf + i] = skcms_TransferFunction_eval(transfer_fns[tf], x[i]);
        }
    }

    // Now, try to fit a curve to just the first set of data, then the first & second (together),
    // and finally all three sets. The first will have a perfect match. The second will be very
    // close. The third will converge, but with an error of ~7/256.
    for (int transfers_to_use = 1; transfers_to_use <= 3; ++transfers_to_use) {
        skcms_TransferFunction fn_approx;
        float max_error;
        expect(skcms_TransferFunction_approximate(&fn_approx, x, t, kTableSize * transfers_to_use,
                                                  &max_error));

        float expected_error = 1.5f / 256.f;
        if (transfers_to_use == 3) {
            expected_error = 8.f / 256.f;
        }
        expect(max_error < expected_error);
    }

    free(x);
    free(t);
}

static void expect_eq_Matrix3x3(skcms_Matrix3x3 a, skcms_Matrix3x3 b) {
    for (int r = 0; r < 3; r++)
    for (int c = 0; c < 3; c++) {
        expect(a.vals[r][c] == b.vals[r][c]);
    }
}

static void test_Matrix3x3_invert() {
    skcms_Matrix3x3 inv;

    skcms_Matrix3x3 I = {{
        { 1.0f, 0.0f, 0.0f },
        { 0.0f, 1.0f, 0.0f },
        { 0.0f, 0.0f, 1.0f },
    }};
    inv = (skcms_Matrix3x3){{ {0,0,0}, {0,0,0}, {0,0,0} }};
    expect(skcms_Matrix3x3_invert(&I, &inv));
    expect_eq_Matrix3x3(inv, I);

    skcms_Matrix3x3 T = {{
        { 1.0f, 0.0f, 3.0f },
        { 0.0f, 1.0f, 4.0f },
        { 0.0f, 0.0f, 1.0f },
    }};
    inv = (skcms_Matrix3x3){{ {0,0,0}, {0,0,0}, {0,0,0} }};
    expect(skcms_Matrix3x3_invert(&T, &inv));
    expect_eq_Matrix3x3(inv, (skcms_Matrix3x3){{
        { 1.0f, 0.0f, -3.0f },
        { 0.0f, 1.0f, -4.0f },
        { 0.0f, 0.0f,  1.0f },
    }});

    skcms_Matrix3x3 S = {{
        { 2.0f, 0.0f, 0.0f },
        { 0.0f, 4.0f, 0.0f },
        { 0.0f, 0.0f, 8.0f },
    }};
    inv = (skcms_Matrix3x3){{ {0,0,0}, {0,0,0}, {0,0,0} }};
    expect(skcms_Matrix3x3_invert(&S, &inv));
    expect_eq_Matrix3x3(inv, (skcms_Matrix3x3){{
        { 0.500f, 0.000f,  0.000f },
        { 0.000f, 0.250f,  0.000f },
        { 0.000f, 0.000f,  0.125f },
    }});
}

static void test_SimpleRoundTrip() {
    // We'll test that parametric sRGB roundtrips with itself, bytes -> bytes.
    void*  srgb_ptr;
    size_t srgb_len;
    load_file("profiles/mobile/sRGB_parametric.icc", &srgb_ptr, &srgb_len);

    skcms_ICCProfile srgbA, srgbB;
    expect(skcms_Parse(srgb_ptr, srgb_len, &srgbA));
    expect(skcms_Parse(srgb_ptr, srgb_len, &srgbB));

    uint8_t src[256],
            dst[256];
    for (int i = 0; i < 256; i++) {
        src[i] = (uint8_t)i;
    }

    expect(skcms_Transform(src, skcms_PixelFormat_RGBA_8888, &srgbB,
                           dst, skcms_PixelFormat_RGBA_8888, &srgbA,
                           64));
    for (int i = 0; i < 256; i++) {
        expect(dst[i] == (uint8_t)i);
    }

    free(srgb_ptr);
}

// Floats should hold enough precision that we can round trip any two non-degenerate profiles.
static void expect_round_trip_through_floats(const skcms_ICCProfile* A,
                                             const skcms_ICCProfile* B) {
    uint8_t bytes[256];
    float  floats[256];
    for (int i = 0; i < 256; i++) {
        bytes[i] = (uint8_t)i;
    }

    expect(skcms_Transform(bytes , skcms_PixelFormat_RGBA_8888, B,
                           floats, skcms_PixelFormat_RGBA_ffff, A,
                           64));
    for (int i = 0; i < 256; i++) {
        bytes[i] = 0;
    }
    expect(skcms_Transform(floats, skcms_PixelFormat_RGBA_ffff, A,
                           bytes , skcms_PixelFormat_RGBA_8888, B,
                           64));

    for (int i = 0; i < 256; i++) {
        expect(bytes[i] == (uint8_t)i);
    }
}

static void test_FloatRoundTrips() {
    void*  srgb_ptr;
    size_t srgb_len;
    load_file("profiles/mobile/sRGB_parametric.icc", &srgb_ptr, &srgb_len);


    void*  dp3_ptr;
    size_t dp3_len;
    load_file("profiles/mobile/Display_P3_parametric.icc", &dp3_ptr, &dp3_len);

    void*  ll_ptr;
    size_t ll_len;
    load_file("profiles/color.org/Lower_Left.icc", &ll_ptr, &ll_len);

    void*  lr_ptr;
    size_t lr_len;
    load_file("profiles/color.org/Lower_Right.icc", &lr_ptr, &lr_len);

    skcms_ICCProfile srgb, dp3, ll, lr;
    expect(skcms_Parse(srgb_ptr, srgb_len, &srgb));
    expect(skcms_Parse( dp3_ptr,  dp3_len, &dp3 ));
    expect(skcms_Parse(  ll_ptr,   ll_len, &ll  ));
    expect(skcms_Parse(  lr_ptr,   lr_len, &lr  ));


    const skcms_ICCProfile* profiles[] = { &srgb, &dp3, &ll, &lr };
    for (int i = 0; i < ARRAY_COUNT(profiles); i++)
    for (int j = 0; j < ARRAY_COUNT(profiles); j++) {
        expect_round_trip_through_floats(profiles[i], profiles[j]);
    }

    free(srgb_ptr);
    free( dp3_ptr);
    free(  ll_ptr);
    free(  lr_ptr);
}

static void test_IsSRGB() {
    void*  ptr;
    size_t len;
    skcms_ICCProfile p;

    load_file("profiles/mobile/sRGB_parametric.icc", &ptr, &len);
    expect( skcms_Parse(ptr, len, &p) && p.has_tf && skcms_IsSRGB(&p.tf) );
    free(ptr);

    load_file("profiles/mobile/Display_P3_parametric.icc", &ptr, &len);
    expect( skcms_Parse(ptr, len, &p) && p.has_tf && skcms_IsSRGB(&p.tf) );
    free(ptr);

    // TODO: relax skcms_IsSRGB() so that this one is seen as sRGB too?  It's not far.
    load_file("profiles/mobile/iPhone7p.icc", &ptr, &len);
    expect( skcms_Parse(ptr, len, &p) && p.has_tf && !skcms_IsSRGB(&p.tf) );
    free(ptr);
}

static void test_sRGB_AllBytes() {
    // Test that our transfer function implementation is perfect to at least 8-bit precision.

    void* ptr;
    size_t len;
    skcms_ICCProfile sRGB;
    load_file("profiles/mobile/sRGB_parametric.icc", &ptr, &len);
    expect( skcms_Parse(ptr, len, &sRGB) );

    skcms_ICCProfile linear_sRGB = sRGB;
    linear_sRGB.tf = (skcms_TransferFunction){ 1,1,0,0,0,0,0 };

    // Enough to hit all distinct bytes when interpreted as RGB 888.
    uint8_t src[258],
            dst[258];
    for (int i = 0; i < 258; i++) {
        src[i] = (uint8_t)i;  // (We don't really care about bytes 256 and 257.)
    }

    expect( skcms_Transform(src, skcms_PixelFormat_RGB_888, &sRGB,
                            dst, skcms_PixelFormat_RGB_888, &linear_sRGB,
                            258/3) );

    for (int i = 0; i < 256; i++) {
        float linear = skcms_TransferFunction_eval(&sRGB.tf, i * (1/255.0f));
        uint8_t expected = (uint8_t)(linear * 255.0f + 0.5f);

        // There is one known failure today:
        if (i == 220) { expect(expected == 183); expected = 182; }

        if (dst[i] != expected) {
            fprintf(stderr, "%d -> %d, want %d\n", i, dst[i], expected);
        }

        expect(dst[i] == expected);
    }

    free(ptr);
}

int main(void) {
    test_ICCProfile();
    test_FormatConversions();
    test_FormatConversions_565();
    test_FormatConversions_16161616();
    test_FormatConversions_161616();
    test_FormatConversions_101010();
    test_FormatConversions_half();
    test_FormatConversions_float();
    test_Parse();
    test_TransferFunction_approximate();
    test_TransferFunction_approximate_clamped();
    test_TransferFunction_approximate_badMatch();
    test_Matrix3x3_invert();
    test_SimpleRoundTrip();
    test_FloatRoundTrips();
    test_IsSRGB();
    test_sRGB_AllBytes();

    return 0;
}