Added type hints

.ci/requirements-mypy.txt

@@ -5,6 +5,7 @@ ipython
 numpy
 packaging
 pytest
+sphinx
 types-defusedxml
 types-olefile
 types-setuptools

Tests/test_imagefile.py

@@ -317,7 +317,13 @@ def test_setimage(self) -> None:
 
         fp = BytesIO()
         ImageFile._save(
-            im, fp, [("MOCK", (xoff, yoff, xoff + xsize, yoff + ysize), 0, "RGB")]
+            im,
+            fp,
+            [
+                ImageFile._Tile(
+                    "MOCK", (xoff, yoff, xoff + xsize, yoff + ysize), 0, "RGB"
+                )
+            ],
         )
 
         assert MockPyEncoder.last
@@ -333,7 +339,7 @@ def test_extents_none(self) -> None:
         im.tile = [("MOCK", None, 32, None)]
 
         fp = BytesIO()
-        ImageFile._save(im, fp, [("MOCK", None, 0, "RGB")])
+        ImageFile._save(im, fp, [ImageFile._Tile("MOCK", None, 0, "RGB")])
 
         assert MockPyEncoder.last
         assert MockPyEncoder.last.state.xoff == 0
@@ -350,15 +356,19 @@ def test_negsize(self) -> None:
         MockPyEncoder.last = None
         with pytest.raises(ValueError):
             ImageFile._save(
-                im, fp, [("MOCK", (xoff, yoff, -10, yoff + ysize), 0, "RGB")]
+                im,
+                fp,
+                [ImageFile._Tile("MOCK", (xoff, yoff, -10, yoff + ysize), 0, "RGB")],
             )
         last: MockPyEncoder | None = MockPyEncoder.last
         assert last
         assert last.cleanup_called
 
         with pytest.raises(ValueError):
             ImageFile._save(
-                im, fp, [("MOCK", (xoff, yoff, xoff + xsize, -10), 0, "RGB")]
+                im,
+                fp,
+                [ImageFile._Tile("MOCK", (xoff, yoff, xoff + xsize, -10), 0, "RGB")],
             )
 
     def test_oversize(self) -> None:
@@ -371,14 +381,22 @@ def test_oversize(self) -> None:
             ImageFile._save(
                 im,
                 fp,
-                [("MOCK", (xoff, yoff, xoff + xsize + 100, yoff + ysize), 0, "RGB")],
+                [
+                    ImageFile._Tile(
+                        "MOCK", (xoff, yoff, xoff + xsize + 100, yoff + ysize), 0, "RGB"
+                    )
+                ],
             )
 
         with pytest.raises(ValueError):
             ImageFile._save(
                 im,
                 fp,
-                [("MOCK", (xoff, yoff, xoff + xsize, yoff + ysize + 100), 0, "RGB")],
+                [
+                    ImageFile._Tile(
+                        "MOCK", (xoff, yoff, xoff + xsize, yoff + ysize + 100), 0, "RGB"
+                    )
+                ],
             )
 
     def test_encode(self) -> None:

docs/example/DdsImagePlugin.py

@@ -14,6 +14,7 @@
 
 import struct
 from io import BytesIO
+from typing import IO
 
 from PIL import Image, ImageFile
 
@@ -94,26 +95,26 @@
 DXT5_FOURCC = 0x35545844
 
 
-def _decode565(bits):
+def _decode565(bits: int) -> tuple[int, int, int]:
     a = ((bits >> 11) & 0x1F) << 3
     b = ((bits >> 5) & 0x3F) << 2
     c = (bits & 0x1F) << 3
     return a, b, c
 
 
-def _c2a(a, b):
+def _c2a(a: int, b: int) -> int:
     return (2 * a + b) // 3
 
 
-def _c2b(a, b):
+def _c2b(a: int, b: int) -> int:
     return (a + b) // 2
 
 
-def _c3(a, b):
+def _c3(a: int, b: int) -> int:
     return (2 * b + a) // 3
 
 
-def _dxt1(data, width, height):
+def _dxt1(data: IO[bytes], width: int, height: int) -> bytes:
     # TODO implement this function as pixel format in decode.c
     ret = bytearray(4 * width * height)
 
@@ -151,7 +152,7 @@ def _dxt1(data, width, height):
     return bytes(ret)
 
 
-def _dxtc_alpha(a0, a1, ac0, ac1, ai):
+def _dxtc_alpha(a0: int, a1: int, ac0: int, ac1: int, ai: int) -> int:
     if ai <= 12:
         ac = (ac0 >> ai) & 7
     elif ai == 15:
@@ -175,7 +176,7 @@ def _dxtc_alpha(a0, a1, ac0, ac1, ai):
     return alpha
 
 
-def _dxt5(data, width, height):
+def _dxt5(data: IO[bytes], width: int, height: int) -> bytes:
     # TODO implement this function as pixel format in decode.c
     ret = bytearray(4 * width * height)
 
@@ -211,7 +212,7 @@ class DdsImageFile(ImageFile.ImageFile):
     format = "DDS"
     format_description = "DirectDraw Surface"
 
-    def _open(self):
+    def _open(self) -> None:
         if not _accept(self.fp.read(4)):
             msg = "not a DDS file"
             raise SyntaxError(msg)
@@ -242,19 +243,20 @@ def _open(self):
         elif fourcc == b"DXT5":
             self.decoder = "DXT5"
         else:
-            msg = f"Unimplemented pixel format {fourcc}"
+            msg = f"Unimplemented pixel format {repr(fourcc)}"
             raise NotImplementedError(msg)
 
         self.tile = [(self.decoder, (0, 0) + self.size, 0, (self.mode, 0, 1))]
 
-    def load_seek(self, pos):
+    def load_seek(self, pos: int) -> None:
         pass
 
 
 class DXT1Decoder(ImageFile.PyDecoder):
     _pulls_fd = True
 
-    def decode(self, buffer):
+    def decode(self, buffer: bytes) -> tuple[int, int]:
+        assert self.fd is not None
         try:
             self.set_as_raw(_dxt1(self.fd, self.state.xsize, self.state.ysize))
         except struct.error as e:
@@ -266,7 +268,8 @@ def decode(self, buffer):
 class DXT5Decoder(ImageFile.PyDecoder):
     _pulls_fd = True
 
-    def decode(self, buffer):
+    def decode(self, buffer: bytes) -> tuple[int, int]:
+        assert self.fd is not None
         try:
             self.set_as_raw(_dxt5(self.fd, self.state.xsize, self.state.ysize))
         except struct.error as e:
@@ -279,7 +282,7 @@ def decode(self, buffer):
 Image.register_decoder("DXT5", DXT5Decoder)
 
 
-def _accept(prefix):
+def _accept(prefix: bytes) -> bool:
     return prefix[:4] == b"DDS "
 
 

docs/handbook/image-file-formats.rst

@@ -1517,19 +1517,21 @@ To add other read or write support, use
 :py:func:`PIL.WmfImagePlugin.register_handler` to register a WMF and EMF
 handler. ::
 
-    from PIL import Image
+    from typing import IO
+
+    from PIL import Image, ImageFile
     from PIL import WmfImagePlugin
 
 
-    class WmfHandler:
-        def open(self, im):
+    class WmfHandler(ImageFile.StubHandler):
+        def open(self, im: ImageFile.StubImageFile) -> None:
             ...
 
-        def load(self, im):
+        def load(self, im: ImageFile.StubImageFile) -> Image.Image:
             ...
             return image
 
-        def save(self, im, fp, filename):
+        def save(self, im: Image.Image, fp: IO[bytes], filename: str) -> None:
             ...
 
 

docs/handbook/tutorial.rst

@@ -186,7 +186,7 @@ Rolling an image
 
 ::
 
-    def roll(im, delta):
+    def roll(im: Image.Image, delta: int) -> Image.Image:
         """Roll an image sideways."""
         xsize, ysize = im.size
 
@@ -211,7 +211,7 @@ Merging images
 
 ::
 
-    def merge(im1, im2):
+    def merge(im1: Image.Image, im2: Image.Image) -> Image.Image:
         w = im1.size[0] + im2.size[0]
         h = max(im1.size[1], im2.size[1])
         im = Image.new("RGBA", (w, h))
@@ -704,7 +704,7 @@ in the current directory can be saved as JPEGs at reduced quality.
     import glob
     from PIL import Image
 
-    def compress_image(source_path, dest_path):
+    def compress_image(source_path: str, dest_path: str) -> None:
         with Image.open(source_path) as img:
             if img.mode != "RGB":
                 img = img.convert("RGB")

docs/handbook/writing-your-own-image-plugin.rst

@@ -53,7 +53,7 @@ true color.
     from PIL import Image, ImageFile
 
 
-    def _accept(prefix):
+    def _accept(prefix: bytes) -> bool:
         return prefix[:4] == b"SPAM"
 
 
@@ -62,7 +62,7 @@ true color.
         format = "SPAM"
         format_description = "Spam raster image"
 
-        def _open(self):
+        def _open(self) -> None:
 
             header = self.fp.read(128).split()
 
@@ -82,7 +82,7 @@ true color.
                 raise SyntaxError(msg)
 
             # data descriptor
-            self.tile = [("raw", (0, 0) + self.size, 128, (self.mode, 0, 1))]
+            self.tile = [ImageFile._Tile("raw", (0, 0) + self.size, 128, (self.mode, 0, 1))]
 
 
     Image.register_open(SpamImageFile.format, SpamImageFile, _accept)

src/PIL/BlpImagePlugin.py

@@ -477,7 +477,7 @@ def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
         fp.write(struct.pack("<i", 5))
         fp.write(struct.pack("<i", 0))
 
-    ImageFile._save(im, fp, [("BLP", (0, 0) + im.size, 0, im.mode)])
+    ImageFile._save(im, fp, [ImageFile._Tile("BLP", (0, 0) + im.size, 0, im.mode)])
 
 
 Image.register_open(BlpImageFile.format, BlpImageFile, _accept)

src/PIL/BmpImagePlugin.py

@@ -482,7 +482,9 @@ def _save(
     if palette:
         fp.write(palette)
 
-    ImageFile._save(im, fp, [("raw", (0, 0) + im.size, 0, (rawmode, stride, -1))])
+    ImageFile._save(
+        im, fp, [ImageFile._Tile("raw", (0, 0) + im.size, 0, (rawmode, stride, -1))]
+    )
 
 
 #

src/PIL/EpsImagePlugin.py

@@ -434,7 +434,7 @@ def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes, eps: int = 1) -
     if hasattr(fp, "flush"):
         fp.flush()
 
-    ImageFile._save(im, fp, [("eps", (0, 0) + im.size, 0, None)])
+    ImageFile._save(im, fp, [ImageFile._Tile("eps", (0, 0) + im.size, 0, None)])
 
     fp.write(b"\n%%%%EndBinary\n")
     fp.write(b"grestore end\n")

src/PIL/GifImagePlugin.py

@@ -591,7 +591,9 @@ def _write_single_frame(
     _write_local_header(fp, im, (0, 0), flags)
 
     im_out.encoderconfig = (8, get_interlace(im))
-    ImageFile._save(im_out, fp, [("gif", (0, 0) + im.size, 0, RAWMODE[im_out.mode])])
+    ImageFile._save(
+        im_out, fp, [ImageFile._Tile("gif", (0, 0) + im.size, 0, RAWMODE[im_out.mode])]
+    )
 
     fp.write(b"\0")  # end of image data
 
@@ -1054,7 +1056,9 @@ def _write_frame_data(
         _write_local_header(fp, im_frame, offset, 0)
 
         ImageFile._save(
-            im_frame, fp, [("gif", (0, 0) + im_frame.size, 0, RAWMODE[im_frame.mode])]
+            im_frame,
+            fp,
+            [ImageFile._Tile("gif", (0, 0) + im_frame.size, 0, RAWMODE[im_frame.mode])],
         )
 
         fp.write(b"\0")  # end of image data

src/PIL/IcoImagePlugin.py

@@ -97,7 +97,9 @@ def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
             if bits != 32:
                 and_mask = Image.new("1", size)
                 ImageFile._save(
-                    and_mask, image_io, [("raw", (0, 0) + size, 0, ("1", 0, -1))]
+                    and_mask,
+                    image_io,
+                    [ImageFile._Tile("raw", (0, 0) + size, 0, ("1", 0, -1))],
                 )
         else:
             frame.save(image_io, "png")

src/PIL/ImImagePlugin.py

@@ -360,7 +360,9 @@ def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
             palette += im_palette[colors * i : colors * (i + 1)]
             palette += b"\x00" * (256 - colors)
         fp.write(palette)  # 768 bytes
-    ImageFile._save(im, fp, [("raw", (0, 0) + im.size, 0, (rawmode, 0, -1))])
+    ImageFile._save(
+        im, fp, [ImageFile._Tile("raw", (0, 0) + im.size, 0, (rawmode, 0, -1))]
+    )
 
 
 #

src/PIL/Image.py

@@ -218,9 +218,10 @@
 # Registries
 
 if TYPE_CHECKING:
+    import mmap
     from xml.etree.ElementTree import Element
 
-    from . import ImageFile, ImagePalette, TiffImagePlugin
+    from . import ImageFile, ImageFilter, ImagePalette, TiffImagePlugin
     from ._typing import NumpyArray, StrOrBytesPath, TypeGuard
 ID: list[str] = []
 OPEN: dict[
@@ -612,7 +613,7 @@
                 logger.debug("Error closing: %s", msg)
 
         if getattr(self, "map", None):
-            self.map = None
+            self.map: mmap.mmap | None = None
 
         # Instead of simply setting to None, we're setting up a
         # deferred error that will better explain that the core image
@@ -1336,9 +1337,6 @@
         self.load()
         return self._new(self.im.expand(xmargin, ymargin))
 
-    if TYPE_CHECKING:
-        from . import ImageFilter
-
     def filter(self, filter: ImageFilter.Filter | type[ImageFilter.Filter]) -> Image:
         """
         Filters this image using the given filter.  For a list of