Merge branch 'main' into feature/png-bit-depth

.ci/requirements-cibw.txt

@@ -1 +1 @@
-cibuildwheel==3.4.0
+cibuildwheel==3.4.1

.ci/requirements-mypy.txt

@@ -1,4 +1,4 @@
-mypy==1.19.1
+mypy==1.20.2
 arro3-compute
 arro3-core
 IceSpringPySideStubs-PyQt6

.github/dependencies.json

@@ -3,12 +3,12 @@
   "bzip2": "1.0.8",
   "freetype": "2.14.3",
   "fribidi": "1.0.16",
-  "harfbuzz": "13.2.1",
+  "harfbuzz": "14.2.0",
   "jpegturbo": "3.1.4.1",
-  "lcms2": "2.18",
+  "lcms2": "2.19",
   "libavif": "1.4.1",
   "libimagequant": "4.4.1",
-  "libpng": "1.6.56",
+  "libpng": "1.6.58",
   "libwebp": "1.6.0",
   "libxcb": "1.17.0",
   "openjpeg": "2.5.4",

.github/workflows/cifuzz.yml

@@ -30,14 +30,14 @@ jobs:
     steps:
     - name: Build Fuzzers
       id: build
-      uses: google/oss-fuzz/infra/cifuzz/actions/build_fuzzers@e41e2f295eb18d630932fdd33d072527ba74c87b # master
+      uses: google/oss-fuzz/infra/cifuzz/actions/build_fuzzers@c11174f47deee98f260dede5d661614bda78ae39 # master
       with:
         oss-fuzz-project-name: 'pillow'
         language: python
         dry-run: false
     - name: Run Fuzzers
       id: run
-      uses: google/oss-fuzz/infra/cifuzz/actions/run_fuzzers@e41e2f295eb18d630932fdd33d072527ba74c87b # master
+      uses: google/oss-fuzz/infra/cifuzz/actions/run_fuzzers@c11174f47deee98f260dede5d661614bda78ae39 # master
       with:
         oss-fuzz-project-name: 'pillow'
         fuzz-seconds: 600

.github/workflows/lint.yml

@@ -25,7 +25,7 @@ jobs:
         with:
           python-version: "3.x"
       - name: Install uv
-        uses: astral-sh/setup-uv@37802adc94f370d6bfd71619e3f0bf239e1f3b78 # v7.6.0
+        uses: astral-sh/setup-uv@08807647e7069bb48b6ef5acd8ec9567f424441b # v8.1.0
       - name: Lint
         run: uvx --with tox-uv tox -e lint
       - name: Mypy

.github/workflows/wheels.yml

@@ -270,7 +270,7 @@ jobs:
           path: dist
           merge-multiple: true
       - name: Upload wheels to scientific-python-nightly-wheels
-        uses: scientific-python/upload-nightly-action@5748273c71e2d8d3a61f3a11a16421c8954f9ecf # 0.6.3
+        uses: scientific-python/upload-nightly-action@e76cfec8a4611fd02808a801b0ff5a7d7c1b2d99 # 0.6.4
         with:
           artifacts_path: dist
           anaconda_nightly_upload_token: ${{ secrets.ANACONDA_ORG_UPLOAD_TOKEN }}

Tests/test_file_png.py

@@ -516,8 +516,9 @@ class TestFilePng:
             im = roundtrip(im)
         assert im.info["transparency"] == (248, 248, 248)
 
-        im = roundtrip(im, transparency=(0, 1, 2))
-        assert im.info["transparency"] == (0, 1, 2)
+        for transparency in ((0, 1, 2), [0, 1, 2]):
+            im = roundtrip(im, transparency=transparency)
+            assert im.info["transparency"] == (0, 1, 2)
 
     def test_trns_p(self, tmp_path: Path) -> None:
         # Check writing a transparency of 0, issue #528
@@ -532,6 +533,36 @@ class TestFilePng:
 
             assert_image_equal(im2.convert("RGBA"), im.convert("RGBA"))
 
+    def test_trns_invalid(self, tmp_path: Path) -> None:
+        out = tmp_path / "temp.png"
+
+        for mode in ("1", "L", "I;16"):
+            im = Image.new(mode, (1, 1))
+            with pytest.raises(
+                ValueError, match=f"transparency for {mode} must be an integer"
+            ):
+                im.save(out, transparency="invalid")
+
+        im = Image.new("I", (1, 1))
+        with pytest.warns(DeprecationWarning, match="Saving I mode images as PNG"):
+            with pytest.raises(ValueError):
+                im.save(out, transparency="invalid")
+
+        im = Image.new("P", (1, 1))
+        with pytest.raises(
+            ValueError, match="transparency for P must be an integer or bytes"
+        ):
+            im.save(out, transparency="invalid")
+
+        im = Image.new("RGB", (1, 1))
+        with pytest.raises(
+            ValueError, match="transparency for RGB must be list or tuple"
+        ):
+            im.save(out, transparency="invalid")
+
+        with pytest.raises(ValueError, match="transparency for RGB must have length 3"):
+            im.save(out, transparency=(1, 2))
+
     def test_trns_null(self) -> None:
         # Check reading images with null tRNS value, issue #1239
         test_file = "Tests/images/tRNS_null_1x1.png"

Tests/test_image.py

@@ -862,7 +862,7 @@ class TestImage:
     def test_exif_webp(self, tmp_path: Path) -> None:
         with Image.open("Tests/images/hopper.webp") as im:
             exif = im.getexif()
-            assert exif == {}
+            assert dict(exif) == {}
 
             out = tmp_path / "temp.webp"
             exif[258] = 8
@@ -884,7 +884,7 @@ class TestImage:
     def test_exif_png(self, tmp_path: Path) -> None:
         with Image.open("Tests/images/exif.png") as im:
             exif = im.getexif()
-            assert exif == {274: 1}
+            assert dict(exif) == {274: 1}
 
             out = tmp_path / "temp.png"
             exif[258] = 8

Tests/test_image_resample.py

@@ -627,3 +627,37 @@ class TestCoreResampleBox:
                 0.4,
                 f">>> {size} {box} {flt}",
             )
+
+
+class TestCoreResample16bpc:
+    # Lanczos weighting during downsampling can push accumulated float sums
+    @pytest.mark.parametrize(
+        "offset",
+        (
+            # below 0. These must be clamped to 0, not corrupted byte-by-byte.
+            0,  # Left half = 65535, right half = 0
+            # above 65535. These must be clamped to 65535, not corrupted byte-by-byte.
+            50,  # # Left half = 0, right half = 65535
+        ),
+    )
+    def test_resampling_clamp_overflow(self, offset: int) -> None:
+        ims = {}
+        width, height = 100, 10
+        for mode in ("I;16", "F"):
+            im = Image.new(mode, (width, height))
+            im.paste(65535, (offset, 0, offset + width // 2, height))
+
+            # 5x downsampling with Lanczos
+            # creates ~8.7% overshoot or undershoot at the step edge
+            ims[mode] = im.resize((20, height), Image.Resampling.LANCZOS)
+
+        for y in range(height):
+            for x in range(20):
+                v = ims["F"].getpixel((x, y))
+                assert isinstance(v, float)
+                expected = max(0, min(65535, round(v)))
+
+                value = ims["I;16"].getpixel((x, y))
+                assert (
+                    value == expected
+                ), f"Pixel ({x}, {y}): expected {expected}, got {value}"

docs/installation/building-from-source.rst

@@ -51,7 +51,7 @@ Many of Pillow's features require external libraries:
 * **littlecms** provides color management
 
   * Pillow version 2.2.1 and below uses liblcms1, Pillow 2.3.0 and
-    above uses liblcms2. Tested with **1.19** and **2.7-2.18**.
+    above uses liblcms2. Tested with **1.19** and **2.7-2.19**.
 
 * **libwebp** provides the WebP format.
 

src/PIL/Image.py

@@ -2639,11 +2639,8 @@ class Image:
         if is_path(fp):
             filename = os.fspath(fp)
             open_fp = True
-        elif fp == sys.stdout:
-            try:
-                fp = sys.stdout.buffer
-            except AttributeError:
-                pass
+        elif fp == sys.stdout and isinstance(sys.stdout, io.TextIOWrapper):
+            fp = sys.stdout.buffer
         if not filename and hasattr(fp, "name") and is_path(fp.name):
             # only set the name for metadata purposes
             filename = os.fspath(fp.name)

src/PIL/PdfParser.py

@@ -383,7 +383,7 @@ class PdfParser:
             msg = "specify buf or f or filename, but not both buf and f"
             raise RuntimeError(msg)
         self.filename = filename
-        self.buf: bytes | bytearray | mmap.mmap | None = buf
+        self.buf: bytes | bytearray | memoryview | mmap.mmap | None = buf
         self.f = f
         self.start_offset = start_offset
         self.should_close_buf = False
@@ -435,7 +435,9 @@ class PdfParser:
         self.seek_end()
 
     def close_buf(self) -> None:
-        if isinstance(self.buf, mmap.mmap):
+        if isinstance(self.buf, memoryview):
+            self.buf.release()
+        elif isinstance(self.buf, mmap.mmap):
             self.buf.close()
         self.buf = None
 

src/PIL/PngImagePlugin.py

@@ -1446,35 +1446,47 @@ def _save(
             palette_bytes += b"\0"
         chunk(fp, b"PLTE", palette_bytes)
 
-    transparency = im.encoderinfo.get("transparency", im.info.get("transparency", None))
+    transparency = im.encoderinfo.get("transparency", im.info.get("transparency"))
 
-    if transparency or transparency == 0:
+    if transparency is not None:
         if im.mode == "P":
             # limit to actual palette size
             alpha_bytes = colors
             if isinstance(transparency, bytes):
                 chunk(fp, b"tRNS", transparency[:alpha_bytes])
-            else:
+            elif isinstance(transparency, int):
                 transparency = max(0, min(255, transparency))
                 alpha = b"\xff" * transparency + b"\0"
                 chunk(fp, b"tRNS", alpha[:alpha_bytes])
+            else:
+                msg = "transparency for P must be an integer or bytes"
+                raise ValueError(msg)
         elif im.mode in ("1", "L", "I", "I;16"):
-            transparency = max(0, min(65535, transparency))
-            chunk(fp, b"tRNS", o16(transparency))
+            if isinstance(transparency, int):
+                transparency = max(0, min(65535, transparency))
+                chunk(fp, b"tRNS", o16(transparency))
+            else:
+                msg = f"transparency for {im.mode} must be an integer"
+                raise ValueError(msg)
         elif im.mode == "RGB":
-            red, green, blue = transparency
-            chunk(fp, b"tRNS", o16(red) + o16(green) + o16(blue))
-        else:
-            if "transparency" in im.encoderinfo:
-                # don't bother with transparency if it's an RGBA
-                # and it's in the info dict. It's probably just stale.
-                msg = "cannot use transparency for this mode"
-                raise OSError(msg)
-    else:
-        if im.mode == "P" and im.im.getpalettemode() == "RGBA":
-            alpha = im.im.getpalette("RGBA", "A")
-            alpha_bytes = colors
-            chunk(fp, b"tRNS", alpha[:alpha_bytes])
+            if not isinstance(transparency, (list, tuple)):
+                msg = "transparency for RGB must be list or tuple"
+                raise ValueError(msg)
+            elif len(transparency) != 3:
+                msg = "transparency for RGB must have length 3"
+                raise ValueError(msg)
+            else:
+                red, green, blue = transparency
+                chunk(fp, b"tRNS", o16(red) + o16(green) + o16(blue))
+        elif im.encoderinfo.get("transparency") is not None:
+            # don't bother with transparency if it's an RGBA
+            # and it's in the info dict. It's probably just stale.
+            msg = "cannot use transparency for this mode"
+            raise OSError(msg)
+    elif im.mode == "P" and im.im.getpalettemode() == "RGBA":
+        alpha = im.im.getpalette("RGBA", "A")
+        alpha_bytes = colors
+        chunk(fp, b"tRNS", alpha[:alpha_bytes])
 
     if dpi := im.encoderinfo.get("dpi"):
         chunk(

src/libImaging/Convert.c

@@ -37,8 +37,6 @@
 #define MAX(a, b) (a) > (b) ? (a) : (b)
 #define MIN(a, b) (a) < (b) ? (a) : (b)
 
-#define CLIP16(v) ((v) <= 0 ? 0 : (v) >= 65535 ? 65535 : (v))
-
 /* ITU-R Recommendation 601-2 (assuming nonlinear RGB) */
 #define L(rgb) ((INT32)(rgb)[0] * 299 + (INT32)(rgb)[1] * 587 + (INT32)(rgb)[2] * 114)
 #define L24(rgb) ((rgb)[0] * 19595 + (rgb)[1] * 38470 + (rgb)[2] * 7471 + 0x8000)

src/libImaging/ImagingUtils.h

@@ -27,6 +27,8 @@
 
 #define CLIP8(v) ((v) <= 0 ? 0 : (v) < 256 ? (v) : 255)
 
+#define CLIP16(v) ((v) <= 0 ? 0 : (v) < 65536 ? (v) : 65535)
+
 /* This is to work around a bug in GCC prior 4.9 in 64 bit mode.
    GCC generates code with partial dependency which is 3 times slower.
    See: https://stackoverflow.com/a/26588074/253146 */

src/libImaging/Resample.c

@@ -492,9 +492,9 @@ ImagingResampleHorizontal_16bpc(
                         << 8)) *
                       k[x];
             }
-            ss_int = ROUND_UP(ss);
-            imOut->image8[yy][xx * 2 + (bigendian ? 1 : 0)] = CLIP8(ss_int % 256);
-            imOut->image8[yy][xx * 2 + (bigendian ? 0 : 1)] = CLIP8(ss_int >> 8);
+            ss_int = CLIP16(ROUND_UP(ss));
+            imOut->image8[yy][xx * 2 + (bigendian ? 1 : 0)] = ss_int & 0xFF;
+            imOut->image8[yy][xx * 2 + (bigendian ? 0 : 1)] = ss_int >> 8;
         }
     }
     ImagingSectionLeave(&cookie);
@@ -531,9 +531,9 @@ ImagingResampleVertical_16bpc(
                        (imIn->image8[y + ymin][xx * 2 + (bigendian ? 0 : 1)] << 8)) *
                       k[y];
             }
-            ss_int = ROUND_UP(ss);
-            imOut->image8[yy][xx * 2 + (bigendian ? 1 : 0)] = CLIP8(ss_int % 256);
-            imOut->image8[yy][xx * 2 + (bigendian ? 0 : 1)] = CLIP8(ss_int >> 8);
+            ss_int = CLIP16(ROUND_UP(ss));
+            imOut->image8[yy][xx * 2 + (bigendian ? 1 : 0)] = ss_int & 0xFF;
+            imOut->image8[yy][xx * 2 + (bigendian ? 0 : 1)] = ss_int >> 8;
         }
     }
     ImagingSectionLeave(&cookie);