Add JPEG XL Open/Read support via libjxl

.ci/install.sh

@@ -55,5 +55,8 @@ pushd depends && sudo ./install_raqm.sh && popd
 # libavif
 pushd depends && sudo ./install_libavif.sh && popd
 
+# libjxl
+pushd depends && sudo ./install_libjxl.sh && popd
+
 # extra test images
 pushd depends && ./install_extra_test_images.sh && popd

.github/workflows/test-mingw.yml

@@ -63,6 +63,7 @@ jobs:
               mingw-w64-x86_64-libavif \
               mingw-w64-x86_64-libimagequant \
               mingw-w64-x86_64-libjpeg-turbo \
+              mingw-w64-x86_64-libjxl \
               mingw-w64-x86_64-libraqm \
               mingw-w64-x86_64-libtiff \
               mingw-w64-x86_64-libwebp \

.github/workflows/test-windows.yml

@@ -175,6 +175,14 @@ jobs:
       if: steps.build-cache.outputs.cache-hit != 'true'
       run: "& winbuild\\build\\build_dep_libimagequant.cmd"
 
+    - name: Build dependencies / highway
+      if: steps.build-cache.outputs.cache-hit != 'true'
+      run: "& winbuild\\build\\build_dep_highway.cmd"
+
+    - name: Build dependencies / libjxl
+      if: steps.build-cache.outputs.cache-hit != 'true'
+      run: "& winbuild\\build\\build_dep_libjxl.cmd"
+
     # Raqm dependencies
     - name: Build dependencies / HarfBuzz
       if: steps.build-cache.outputs.cache-hit != 'true'

.github/workflows/wheels-dependencies.sh

@@ -99,6 +99,7 @@ HARFBUZZ_VERSION=12.2.0
 LIBPNG_VERSION=1.6.53
 JPEGTURBO_VERSION=3.1.3
 OPENJPEG_VERSION=2.5.4
+JPEGXL_VERSION=0.11.1
 XZ_VERSION=5.8.2
 ZSTD_VERSION=1.5.7
 TIFF_VERSION=4.7.1
@@ -161,6 +162,21 @@ function build_brotli {
     touch brotli-stamp
 }
 
+function build_jpegxl {
+    if [ -e jpegxl-stamp ]; then return; fi
+
+    local out_dir=$(fetch_unpack https://github.com/google/highway/archive/1.3.0.tar.gz)
+    (cd $out_dir \
+        && cmake -DCMAKE_INSTALL_PREFIX=$BUILD_PREFIX -DCMAKE_INSTALL_LIBDIR=$BUILD_PREFIX/lib -DCMAKE_INSTALL_NAME_DIR=$BUILD_PREFIX/lib $HOST_CMAKE_FLAGS . \
+        && make -j4 install)
+
+    local out_dir=$(fetch_unpack https://github.com/libjxl/libjxl/archive/v$JPEGXL_VERSION.tar.gz)
+    (cd $out_dir \
+        && cmake -DCMAKE_INSTALL_PREFIX=$BUILD_PREFIX -DCMAKE_INSTALL_LIBDIR=$BUILD_PREFIX/lib -DCMAKE_INSTALL_NAME_DIR=$BUILD_PREFIX/lib -DJPEGXL_ENABLE_SJPEG=OFF -DJPEGXL_ENABLE_SKCMS=OFF -DBUILD_TESTING=OFF $HOST_CMAKE_FLAGS . \
+        && make -j4 install)
+    touch jpegxl-stamp
+}
+
 function build_harfbuzz {
     if [ -e harfbuzz-stamp ]; then return; fi
     python3 -m pip install meson ninja
@@ -293,19 +309,6 @@ function build {
     build_libpng
     build_lcms2
     build_openjpeg
-
-    webp_cflags="-O3 -DNDEBUG"
-    if [[ -n "$IS_MACOS" ]]; then
-        webp_cflags="$webp_cflags -Wl,-headerpad_max_install_names"
-    fi
-    webp_ldflags=""
-    if [[ -n "$IOS_SDK" ]]; then
-        webp_ldflags="$webp_ldflags -llzma -lz"
-    fi
-    CFLAGS="$CFLAGS $webp_cflags" LDFLAGS="$LDFLAGS $webp_ldflags" build_simple libwebp $LIBWEBP_VERSION \
-        https://storage.googleapis.com/downloads.webmproject.org/releases/webp tar.gz \
-        --enable-libwebpmux --enable-libwebpdemux
-
     build_brotli
 
     if [[ -n "$IS_MACOS" ]]; then
@@ -323,7 +326,23 @@ function build {
         # On iOS, there's no vendor-provided raqm, and we can't ship it due to
         # licensing, so there's no point building harfbuzz.
         build_harfbuzz
+
+        if [[ "$MB_ML_VER" != 2014 ]]; then
+            build_jpegxl
+        fi
     fi
+
+    webp_cflags="-O3 -DNDEBUG"
+    if [[ -n "$IS_MACOS" ]]; then
+        webp_cflags="$webp_cflags -Wl,-headerpad_max_install_names"
+    fi
+    webp_ldflags=""
+    if [[ -n "$IOS_SDK" ]]; then
+        webp_ldflags="$webp_ldflags -llzma -lz"
+    fi
+    CFLAGS="$CFLAGS $webp_cflags" LDFLAGS="$LDFLAGS $webp_ldflags" build_simple libwebp $LIBWEBP_VERSION \
+        https://storage.googleapis.com/downloads.webmproject.org/releases/webp tar.gz \
+        --enable-libwebpmux --enable-libwebpdemux
 }
 
 function create_meson_cross_config {

Tests/test_file_jxl.py

@@ -0,0 +1,64 @@
+from __future__ import annotations
+
+import os
+import re
+
+import pytest
+
+from PIL import Image, JpegXlImagePlugin, UnidentifiedImageError, features
+
+from .helper import assert_image_similar_tofile, skip_unless_feature
+
+try:
+    from PIL import _jpegxl
+except ImportError:
+    pass
+
+
+class TestUnsupportedJpegXl:
+    def test_unsupported(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        monkeypatch.setattr(JpegXlImagePlugin, "SUPPORTED", False)
+
+        with pytest.raises(OSError):
+            with pytest.warns(UserWarning, match="JXL support not installed"):
+                Image.open("Tests/images/jxl/hopper.jxl")
+
+
+@skip_unless_feature("jpegxl")
+class TestFileJpegXl:
+    def test_version(self) -> None:
+        version = features.version_module("jpegxl")
+        assert version is not None
+        assert re.search(r"\d+\.\d+\.\d+$", version)
+
+    @pytest.mark.parametrize(
+        "mode, test_file",
+        (
+            ("1", "hopper_bw_500.png"),
+            ("L", "hopper_gray.jpg"),
+            ("I;16", "jxl/16bit_subcutaneous.cropped.png"),
+            ("RGB", "hopper.jpg"),
+            ("RGBA", "transparent.png"),
+        ),
+    )
+    def test_read(self, mode: str, test_file: str) -> None:
+        with Image.open(
+            "Tests/images/jxl/"
+            + os.path.splitext(os.path.basename(test_file))[0]
+            + ".jxl"
+        ) as im:
+            assert im.format == "JPEG XL"
+            assert im.mode == mode
+
+            assert_image_similar_tofile(im, "Tests/images/" + test_file, 1.9)
+
+    def test_unknown_mode(self) -> None:
+        with pytest.raises(UnidentifiedImageError):
+            Image.open("Tests/images/jxl/unknown_mode.jxl")
+
+    def test_JpegXlDecode_with_invalid_args(self) -> None:
+        """
+        Calling decoder functions with no arguments should result in an error.
+        """
+        with pytest.raises(TypeError):
+            _jpegxl.JpegXlDecoder()

Tests/test_file_jxl_animated.py

@@ -0,0 +1,76 @@
+from __future__ import annotations
+
+import pytest
+
+from PIL import Image
+
+from .helper import assert_image_equal, skip_unless_feature
+
+pytestmark = skip_unless_feature("jpegxl")
+
+
+def test_n_frames() -> None:
+    """Ensure that jxl format sets n_frames and is_animated attributes correctly."""
+
+    with Image.open("Tests/images/jxl/hopper.jxl") as im:
+        assert im.n_frames == 1
+        assert not im.is_animated
+
+    with Image.open("Tests/images/jxl/iss634.jxl") as im:
+        assert im.n_frames == 41
+        assert im.is_animated
+
+
+def test_duration() -> None:
+    with Image.open("Tests/images/jxl/iss634.jxl") as im:
+        assert im.info["duration"] == 70
+        assert im.info["timestamp"] == 0
+
+        im.seek(2)
+        assert im.info["duration"] == 60
+        assert im.info["timestamp"] == 140
+
+
+def test_seek() -> None:
+    """
+    Open an animated jxl file, and then try seeking through frames in reverse-order,
+    verifying the durations are correct.
+    """
+
+    with Image.open("Tests/images/jxl/traffic_light.jxl") as im1:
+        with Image.open("Tests/images/jxl/traffic_light.gif") as im2:
+            assert im1.n_frames == im2.n_frames
+            assert im1.is_animated
+
+            # Traverse frames in reverse, checking timestamps and durations
+            total_duration = 0
+            for frame in reversed(range(im1.n_frames)):
+                im1.seek(frame)
+                im2.seek(frame)
+
+                assert_image_equal(im1.convert("RGB"), im2.convert("RGB"))
+
+                total_duration += im1.info["duration"]
+                assert im1.info["duration"] == im2.info["duration"]
+                assert im1.info["timestamp"] == im1.info["timestamp"]
+            assert total_duration == 8000
+
+            assert im1.tell() == 0
+            assert im2.tell() == 0
+
+            im1.seek(0)
+            im1.load()
+            im2.seek(0)
+            im2.load()
+
+
+def test_seek_errors() -> None:
+    with Image.open("Tests/images/jxl/iss634.jxl") as im:
+        with pytest.raises(EOFError, match="attempt to seek outside sequence"):
+            im.seek(-1)
+
+        im.seek(1)
+        with pytest.raises(EOFError, match="no more images in JPEG XL file"):
+            im.seek(47)
+
+        assert im.tell() == 1

Tests/test_file_jxl_metadata.py

@@ -0,0 +1,114 @@
+from __future__ import annotations
+
+from types import ModuleType
+
+import pytest
+
+from PIL import Image, JpegXlImagePlugin
+
+from .helper import skip_unless_feature
+
+pytestmark = skip_unless_feature("jpegxl")
+
+ElementTree: ModuleType | None
+try:
+    from defusedxml import ElementTree
+except ImportError:
+    ElementTree = None
+
+
+# cjxl flower.jpg flower.jxl --lossless_jpeg=0 -q 75 -e 8
+
+# >>> from PIL import Image
+# >>> with Image.open('Tests/images/flower2.webp') as im:
+# >>>   with open('/tmp/xmp.xml', 'wb') as f:
+# >>>     f.write(im.info['xmp'])
+# cjxl flower2.jpg flower2.jxl --lossless_jpeg=0 -q 75 -e 8 -x xmp=/tmp/xmp.xml
+
+
+def test_read_exif_metadata() -> None:
+    with Image.open("Tests/images/jxl/flower.jxl") as im:
+        assert im.format == "JPEG XL"
+        exif_data = im.info["exif"]
+
+        exif = im.getexif()
+
+    # Camera make
+    assert exif[271] == "Canon"
+
+    with Image.open("Tests/images/flower.jpg") as im_jpeg:
+        expected_exif = im_jpeg.info["exif"]
+
+    # JPEG XL always returns exif without "Exif\x00\x00" prefix
+    assert exif_data == expected_exif[6:]
+
+
+def test_read_exif_metadata_without_prefix() -> None:
+    with Image.open("Tests/images/jxl/flower2.jxl") as im:
+        # Assert prefix is not present
+        assert im.info["exif"][:6] != b"Exif\x00\x00"
+
+        exif = im.getexif()
+    assert exif[305] == "Adobe Photoshop CS6 (Macintosh)"
+
+
+def test_read_icc_profile() -> None:
+    with Image.open("Tests/images/jxl/flower.jxl") as im:
+        assert "icc_profile" in im.info
+
+
+def test_getxmp() -> None:
+    with Image.open("Tests/images/jxl/flower.jxl") as im:
+        assert "xmp" not in im.info
+        if ElementTree is None:
+            with pytest.warns(
+                UserWarning,
+                match="XMP data cannot be read without defusedxml dependency",
+            ):
+                xmp = im.getxmp()
+        else:
+            xmp = im.getxmp()
+        assert xmp == {}
+
+    with Image.open("Tests/images/jxl/flower2.jxl") as im:
+        if ElementTree is None:
+            with pytest.warns(
+                UserWarning,
+                match="XMP data cannot be read without defusedxml dependency",
+            ):
+                assert im.getxmp() == {}
+        else:
+            assert "xmp" in im.info
+            assert (
+                im.getxmp()["xmpmeta"]["xmptk"]
+                == "Adobe XMP Core 5.3-c011 66.145661, 2012/02/06-14:56:27        "
+            )
+
+
+def test_4_byte_exif(monkeypatch: pytest.MonkeyPatch) -> None:
+    class _mock_jpegxl:
+        class JpegXlDecoder:
+            def __init__(self, b: bytes) -> None:
+                pass
+
+            def get_info(self) -> tuple[tuple[int, int], str, int, int, int, int, int]:
+                return ((1, 1), "L", 0, 0, 0, 0, 0)
+
+            def get_icc(self) -> None:
+                pass
+
+            def get_exif(self) -> bytes:
+                return b"\0\0\0\0"
+
+            def get_xmp(self) -> None:
+                pass
+
+    monkeypatch.setattr(JpegXlImagePlugin, "_jpegxl", _mock_jpegxl)
+
+    with Image.open("Tests/images/jxl/hopper.jxl") as im:
+        assert "exif" not in im.info
+
+
+def test_read_exif_metadata_empty() -> None:
+    with Image.open("Tests/images/jxl/hopper.jxl") as im:
+        assert im.getexif() == {}