test_imagecms.py

import datetime
import os
import re
from io import BytesIO

import pytest
from PIL import Image, ImageMode, features

from .helper import assert_image, assert_image_equal, assert_image_similar, hopper

try:
    from PIL import ImageCms
    from PIL.ImageCms import ImageCmsProfile

    ImageCms.core.profile_open
except ImportError:
    # Skipped via setup_module()
    pass


SRGB = "Tests/icc/sRGB_IEC61966-2-1_black_scaled.icc"
HAVE_PROFILE = os.path.exists(SRGB)


def setup_module():
    try:
        from PIL import ImageCms

        # need to hit getattr to trigger the delayed import error
        ImageCms.core.profile_open
    except ImportError as v:
        pytest.skip(str(v))


def skip_missing():
    if not HAVE_PROFILE:
        pytest.skip("SRGB profile not available")


def test_sanity():
    # basic smoke test.
    # this mostly follows the cms_test outline.

    v = ImageCms.versions()  # should return four strings
    assert v[0] == "1.0.0 pil"
    assert list(map(type, v)) == [str, str, str, str]

    # internal version number
    assert re.search(r"\d+\.\d+$", features.version_module("littlecms2"))

    skip_missing()
    i = ImageCms.profileToProfile(hopper(), SRGB, SRGB)
    assert_image(i, "RGB", (128, 128))

    i = hopper()
    ImageCms.profileToProfile(i, SRGB, SRGB, inPlace=True)
    assert_image(i, "RGB", (128, 128))

    t = ImageCms.buildTransform(SRGB, SRGB, "RGB", "RGB")
    i = ImageCms.applyTransform(hopper(), t)
    assert_image(i, "RGB", (128, 128))

    with hopper() as i:
        t = ImageCms.buildTransform(SRGB, SRGB, "RGB", "RGB")
        ImageCms.applyTransform(hopper(), t, inPlace=True)
        assert_image(i, "RGB", (128, 128))

    p = ImageCms.createProfile("sRGB")
    o = ImageCms.getOpenProfile(SRGB)
    t = ImageCms.buildTransformFromOpenProfiles(p, o, "RGB", "RGB")
    i = ImageCms.applyTransform(hopper(), t)
    assert_image(i, "RGB", (128, 128))

    t = ImageCms.buildProofTransform(SRGB, SRGB, SRGB, "RGB", "RGB")
    assert t.inputMode == "RGB"
    assert t.outputMode == "RGB"
    i = ImageCms.applyTransform(hopper(), t)
    assert_image(i, "RGB", (128, 128))

    # test PointTransform convenience API
    hopper().point(t)


def test_name():
    skip_missing()
    # get profile information for file
    assert (
        ImageCms.getProfileName(SRGB).strip()
        == "IEC 61966-2-1 Default RGB Colour Space - sRGB"
    )


def test_info():
    skip_missing()
    assert ImageCms.getProfileInfo(SRGB).splitlines() == [
        "sRGB IEC61966-2-1 black scaled",
        "",
        "Copyright International Color Consortium, 2009",
        "",
    ]


def test_copyright():
    skip_missing()
    assert (
        ImageCms.getProfileCopyright(SRGB).strip()
        == "Copyright International Color Consortium, 2009"
    )


def test_manufacturer():
    skip_missing()
    assert ImageCms.getProfileManufacturer(SRGB).strip() == ""


def test_model():
    skip_missing()
    assert (
        ImageCms.getProfileModel(SRGB).strip()
        == "IEC 61966-2-1 Default RGB Colour Space - sRGB"
    )


def test_description():
    skip_missing()
    assert (
        ImageCms.getProfileDescription(SRGB).strip() == "sRGB IEC61966-2-1 black scaled"
    )


def test_intent():
    skip_missing()
    assert ImageCms.getDefaultIntent(SRGB) == 0
    support = ImageCms.isIntentSupported(
        SRGB, ImageCms.INTENT_ABSOLUTE_COLORIMETRIC, ImageCms.DIRECTION_INPUT
    )
    assert support == 1


def test_profile_object():
    # same, using profile object
    p = ImageCms.createProfile("sRGB")
    # assert ImageCms.getProfileName(p).strip() == "sRGB built-in - (lcms internal)"
    # assert ImageCms.getProfileInfo(p).splitlines() ==
    #     ["sRGB built-in", "", "WhitePoint : D65 (daylight)", "", ""]
    assert ImageCms.getDefaultIntent(p) == 0
    support = ImageCms.isIntentSupported(
        p, ImageCms.INTENT_ABSOLUTE_COLORIMETRIC, ImageCms.DIRECTION_INPUT
    )
    assert support == 1


def test_extensions():
    # extensions

    with Image.open("Tests/images/rgb.jpg") as i:
        p = ImageCms.getOpenProfile(BytesIO(i.info["icc_profile"]))
    assert (
        ImageCms.getProfileName(p).strip()
        == "IEC 61966-2.1 Default RGB colour space - sRGB"
    )


def test_exceptions():
    # Test mode mismatch
    psRGB = ImageCms.createProfile("sRGB")
    pLab = ImageCms.createProfile("LAB")
    t = ImageCms.buildTransform(pLab, psRGB, "LAB", "RGB")
    with pytest.raises(ValueError):
        t.apply_in_place(hopper("RGBA"))

    # the procedural pyCMS API uses PyCMSError for all sorts of errors
    with hopper() as im:
        with pytest.raises(ImageCms.PyCMSError):
            ImageCms.profileToProfile(im, "foo", "bar")
    with pytest.raises(ImageCms.PyCMSError):
        ImageCms.buildTransform("foo", "bar", "RGB", "RGB")
    with pytest.raises(ImageCms.PyCMSError):
        ImageCms.getProfileName(None)
    skip_missing()
    with pytest.raises(ImageCms.PyCMSError):
        ImageCms.isIntentSupported(SRGB, None, None)


def test_display_profile():
    # try fetching the profile for the current display device
    ImageCms.get_display_profile()


def test_lab_color_profile():
    ImageCms.createProfile("LAB", 5000)
    ImageCms.createProfile("LAB", 6500)


def test_unsupported_color_space():
    with pytest.raises(ImageCms.PyCMSError):
        ImageCms.createProfile("unsupported")


def test_invalid_color_temperature():
    with pytest.raises(ImageCms.PyCMSError):
        ImageCms.createProfile("LAB", "invalid")


def test_simple_lab():
    i = Image.new("RGB", (10, 10), (128, 128, 128))

    psRGB = ImageCms.createProfile("sRGB")
    pLab = ImageCms.createProfile("LAB")
    t = ImageCms.buildTransform(psRGB, pLab, "RGB", "LAB")

    i_lab = ImageCms.applyTransform(i, t)

    assert i_lab.mode == "LAB"

    k = i_lab.getpixel((0, 0))
    # not a linear luminance map. so L != 128:
    assert k == (137, 128, 128)

    l_data = i_lab.getdata(0)
    a_data = i_lab.getdata(1)
    b_data = i_lab.getdata(2)

    assert list(l_data) == [137] * 100
    assert list(a_data) == [128] * 100
    assert list(b_data) == [128] * 100


def test_lab_color():
    psRGB = ImageCms.createProfile("sRGB")
    pLab = ImageCms.createProfile("LAB")
    t = ImageCms.buildTransform(psRGB, pLab, "RGB", "LAB")

    # Need to add a type mapping for some PIL type to TYPE_Lab_8 in findLCMSType, and
    # have that mapping work back to a PIL mode (likely RGB).
    i = ImageCms.applyTransform(hopper(), t)
    assert_image(i, "LAB", (128, 128))

    # i.save('temp.lab.tif')  # visually verified vs PS.

    with Image.open("Tests/images/hopper.Lab.tif") as target:
        assert_image_similar(i, target, 3.5)


def test_lab_srgb():
    psRGB = ImageCms.createProfile("sRGB")
    pLab = ImageCms.createProfile("LAB")
    t = ImageCms.buildTransform(pLab, psRGB, "LAB", "RGB")

    with Image.open("Tests/images/hopper.Lab.tif") as img:
        img_srgb = ImageCms.applyTransform(img, t)

    # img_srgb.save('temp.srgb.tif') # visually verified vs ps.

    assert_image_similar(hopper(), img_srgb, 30)
    assert img_srgb.info["icc_profile"]

    profile = ImageCmsProfile(BytesIO(img_srgb.info["icc_profile"]))
    assert "sRGB" in ImageCms.getProfileDescription(profile)


def test_lab_roundtrip():
    # check to see if we're at least internally consistent.
    psRGB = ImageCms.createProfile("sRGB")
    pLab = ImageCms.createProfile("LAB")
    t = ImageCms.buildTransform(psRGB, pLab, "RGB", "LAB")

    t2 = ImageCms.buildTransform(pLab, psRGB, "LAB", "RGB")

    i = ImageCms.applyTransform(hopper(), t)

    assert i.info["icc_profile"] == ImageCmsProfile(pLab).tobytes()

    out = ImageCms.applyTransform(i, t2)

    assert_image_similar(hopper(), out, 2)


def test_profile_tobytes():
    with Image.open("Tests/images/rgb.jpg") as i:
        p = ImageCms.getOpenProfile(BytesIO(i.info["icc_profile"]))

    p2 = ImageCms.getOpenProfile(BytesIO(p.tobytes()))

    # not the same bytes as the original icc_profile, but it does roundtrip
    assert p.tobytes() == p2.tobytes()
    assert ImageCms.getProfileName(p) == ImageCms.getProfileName(p2)
    assert ImageCms.getProfileDescription(p) == ImageCms.getProfileDescription(p2)


def test_extended_information():
    skip_missing()
    o = ImageCms.getOpenProfile(SRGB)
    p = o.profile

    def assert_truncated_tuple_equal(tup1, tup2, digits=10):
        # Helper function to reduce precision of tuples of floats
        # recursively and then check equality.
        power = 10 ** digits

        def truncate_tuple(tuple_or_float):
            return tuple(
                truncate_tuple(val)
                if isinstance(val, tuple)
                else int(val * power) / power
                for val in tuple_or_float
            )

        assert truncate_tuple(tup1) == truncate_tuple(tup2)

    assert p.attributes == 4294967296
    assert_truncated_tuple_equal(
        p.blue_colorant,
        (
            (0.14306640625, 0.06060791015625, 0.7140960693359375),
            (0.1558847490315394, 0.06603820639433387, 0.06060791015625),
        ),
    )
    assert_truncated_tuple_equal(
        p.blue_primary,
        (
            (0.14306641366715667, 0.06060790921083026, 0.7140960805782015),
            (0.15588475410450106, 0.06603820408959558, 0.06060790921083026),
        ),
    )
    assert_truncated_tuple_equal(
        p.chromatic_adaptation,
        (
            (
                (1.04791259765625, 0.0229339599609375, -0.050201416015625),
                (0.02960205078125, 0.9904632568359375, -0.0170745849609375),
                (-0.009246826171875, 0.0150604248046875, 0.7517852783203125),
            ),
            (
                (1.0267159024652783, 0.022470062342089134, 0.0229339599609375),
                (0.02951378324103937, 0.9875098886387147, 0.9904632568359375),
                (-0.012205438066465256, 0.01987915407854985, 0.0150604248046875),
            ),
        ),
    )
    assert p.chromaticity is None
    assert p.clut == {
        0: (False, False, True),
        1: (False, False, True),
        2: (False, False, True),
        3: (False, False, True),
    }

    assert p.colorant_table is None
    assert p.colorant_table_out is None
    assert p.colorimetric_intent is None
    assert p.connection_space == "XYZ "
    assert p.copyright == "Copyright International Color Consortium, 2009"
    assert p.creation_date == datetime.datetime(2009, 2, 27, 21, 36, 31)
    assert p.device_class == "mntr"
    assert_truncated_tuple_equal(
        p.green_colorant,
        (
            (0.3851470947265625, 0.7168731689453125, 0.097076416015625),
            (0.32119769927720654, 0.5978443449048152, 0.7168731689453125),
        ),
    )
    assert_truncated_tuple_equal(
        p.green_primary,
        (
            (0.3851470888162112, 0.7168731974161346, 0.09707641738998518),
            (0.32119768793686687, 0.5978443567149709, 0.7168731974161346),
        ),
    )
    assert p.header_flags == 0
    assert p.header_manufacturer == "\x00\x00\x00\x00"
    assert p.header_model == "\x00\x00\x00\x00"
    assert p.icc_measurement_condition == {
        "backing": (0.0, 0.0, 0.0),
        "flare": 0.0,
        "geo": "unknown",
        "observer": 1,
        "illuminant_type": "D65",
    }
    assert p.icc_version == 33554432
    assert p.icc_viewing_condition is None
    assert p.intent_supported == {
        0: (True, True, True),
        1: (True, True, True),
        2: (True, True, True),
        3: (True, True, True),
    }
    assert p.is_matrix_shaper
    assert p.luminance == ((0.0, 80.0, 0.0), (0.0, 1.0, 80.0))
    assert p.manufacturer is None
    assert_truncated_tuple_equal(
        p.media_black_point,
        (
            (0.012054443359375, 0.0124969482421875, 0.01031494140625),
            (0.34573304157549234, 0.35842450765864337, 0.0124969482421875),
        ),
    )
    assert_truncated_tuple_equal(
        p.media_white_point,
        (
            (0.964202880859375, 1.0, 0.8249053955078125),
            (0.3457029219802284, 0.3585375327567059, 1.0),
        ),
    )
    assert_truncated_tuple_equal(
        (p.media_white_point_temperature,), (5000.722328847392,)
    )
    assert p.model == "IEC 61966-2-1 Default RGB Colour Space - sRGB"

    assert p.perceptual_rendering_intent_gamut is None

    assert p.profile_description == "sRGB IEC61966-2-1 black scaled"
    assert p.profile_id == b")\xf8=\xde\xaf\xf2U\xaexB\xfa\xe4\xca\x839\r"
    assert_truncated_tuple_equal(
        p.red_colorant,
        (
            (0.436065673828125, 0.2224884033203125, 0.013916015625),
            (0.6484536316398539, 0.3308524880306778, 0.2224884033203125),
        ),
    )
    assert_truncated_tuple_equal(
        p.red_primary,
        (
            (0.43606566581047446, 0.22248840582960838, 0.013916015621759925),
            (0.6484536250319214, 0.3308524944738204, 0.22248840582960838),
        ),
    )
    assert p.rendering_intent == 0
    assert p.saturation_rendering_intent_gamut is None
    assert p.screening_description is None
    assert p.target is None
    assert p.technology == "CRT "
    assert p.version == 2.0
    assert p.viewing_condition == "Reference Viewing Condition in IEC 61966-2-1"
    assert p.xcolor_space == "RGB "


def test_profile_typesafety():
    """ Profile init type safety

    prepatch, these would segfault, postpatch they should emit a typeerror
    """

    with pytest.raises(TypeError):
        ImageCms.ImageCmsProfile(0).tobytes()
    with pytest.raises(TypeError):
        ImageCms.ImageCmsProfile(1).tobytes()


def assert_aux_channel_preserved(mode, transform_in_place, preserved_channel):
    def create_test_image():
        # set up test image with something interesting in the tested aux channel.
        # fmt: off
        nine_grid_deltas = [
            (-1, -1), (-1, 0), (-1, 1),
            (0,  -1),  (0, 0),  (0, 1),
            (1,  -1),  (1, 0),  (1, 1),
        ]
        # fmt: on
        chans = []
        bands = ImageMode.getmode(mode).bands
        for band_ndx in range(len(bands)):
            channel_type = "L"  # 8-bit unorm
            channel_pattern = hopper(channel_type)

            # paste pattern with varying offsets to avoid correlation
            # potentially hiding some bugs (like channels getting mixed).
            paste_offset = (
                int(band_ndx / len(bands) * channel_pattern.size[0]),
                int(band_ndx / (len(bands) * 2) * channel_pattern.size[1]),
            )
            channel_data = Image.new(channel_type, channel_pattern.size)
            for delta in nine_grid_deltas:
                channel_data.paste(
                    channel_pattern,
                    tuple(
                        paste_offset[c] + delta[c] * channel_pattern.size[c]
                        for c in range(2)
                    ),
                )
            chans.append(channel_data)
        return Image.merge(mode, chans)

    source_image = create_test_image()
    source_image_aux = source_image.getchannel(preserved_channel)

    # create some transform, it doesn't matter which one
    source_profile = ImageCms.createProfile("sRGB")
    destination_profile = ImageCms.createProfile("sRGB")
    t = ImageCms.buildTransform(
        source_profile, destination_profile, inMode=mode, outMode=mode
    )

    # apply transform
    if transform_in_place:
        ImageCms.applyTransform(source_image, t, inPlace=True)
        result_image = source_image
    else:
        result_image = ImageCms.applyTransform(source_image, t, inPlace=False)
    result_image_aux = result_image.getchannel(preserved_channel)

    assert_image_equal(source_image_aux, result_image_aux)


def test_preserve_auxiliary_channels_rgba():
    assert_aux_channel_preserved(
        mode="RGBA", transform_in_place=False, preserved_channel="A"
    )


def test_preserve_auxiliary_channels_rgba_in_place():
    assert_aux_channel_preserved(
        mode="RGBA", transform_in_place=True, preserved_channel="A"
    )


def test_preserve_auxiliary_channels_rgbx():
    assert_aux_channel_preserved(
        mode="RGBX", transform_in_place=False, preserved_channel="X"
    )


def test_preserve_auxiliary_channels_rgbx_in_place():
    assert_aux_channel_preserved(
        mode="RGBX", transform_in_place=True, preserved_channel="X"
    )


def test_auxiliary_channels_isolated():
    # test data in aux channels does not affect non-aux channels
    aux_channel_formats = [
        # format, profile, color-only format, source test image
        ("RGBA", "sRGB", "RGB", hopper("RGBA")),
        ("RGBX", "sRGB", "RGB", hopper("RGBX")),
        ("LAB", "LAB", "LAB", Image.open("Tests/images/hopper.Lab.tif")),
    ]
    for src_format in aux_channel_formats:
        for dst_format in aux_channel_formats:
            for transform_in_place in [True, False]:
                # inplace only if format doesn't change
                if transform_in_place and src_format[0] != dst_format[0]:
                    continue

                # convert with and without AUX data, test colors are equal
                source_profile = ImageCms.createProfile(src_format[1])
                destination_profile = ImageCms.createProfile(dst_format[1])
                source_image = src_format[3]
                test_transform = ImageCms.buildTransform(
                    source_profile,
                    destination_profile,
                    inMode=src_format[0],
                    outMode=dst_format[0],
                )

                # test conversion from aux-ful source
                if transform_in_place:
                    test_image = source_image.copy()
                    ImageCms.applyTransform(test_image, test_transform, inPlace=True)
                else:
                    test_image = ImageCms.applyTransform(
                        source_image, test_transform, inPlace=False
                    )

                # reference conversion from aux-less source
                reference_transform = ImageCms.buildTransform(
                    source_profile,
                    destination_profile,
                    inMode=src_format[2],
                    outMode=dst_format[2],
                )
                reference_image = ImageCms.applyTransform(
                    source_image.convert(src_format[2]), reference_transform
                )

                assert_image_equal(test_image.convert(dst_format[2]), reference_image)