Memory map rotated TIFF images at stored size

Tests/test_file_libtiff.py

@@ -1256,7 +1256,8 @@ def test_jpeg_short_strip(self, tiled: bool) -> None:
     def test_orientation(self) -> None:
         with Image.open("Tests/images/g4_orientation_1.tif") as base_im:
             for i in range(2, 9):
-                with Image.open("Tests/images/g4_orientation_" + str(i) + ".tif") as im:
+                infile = "Tests/images/g4_orientation_" + str(i) + ".tif"
+                with Image.open(infile) as im:
                     assert isinstance(im, TiffImagePlugin.TiffImageFile)
                     assert 274 in im.tag_v2
 
@@ -1265,6 +1266,14 @@ def test_orientation(self) -> None:
 
                     assert_image_similar(base_im, im, 0.7)
 
+                with Image.open(infile) as im:
+                    assert im.size == (590, 88)
+
+                    im.tile.append(im.tile[0])
+                    with pytest.raises(OSError, match="Not exactly one tile"):
+                        im.load()
+                    assert im.size == (590, 88)
+
     def test_exif_transpose(self) -> None:
         with Image.open("Tests/images/g4_orientation_1.tif") as base_im:
             for i in range(2, 9):

Tests/test_file_tiff.py

@@ -556,6 +556,25 @@ def test_exif_frames(self) -> None:
             im.seek(1)
             assert im.getexif()[273] == (1408, 1907)
 
+    @pytest.mark.parametrize(
+        "orientation, method",
+        (
+            (5, Image.Transpose.TRANSPOSE),
+            (6, Image.Transpose.ROTATE_270),
+            (7, Image.Transpose.TRANSVERSE),
+            (8, Image.Transpose.ROTATE_90),
+        ),
+    )
+    def test_orientation_mmap(
+        self, orientation: int, method: Image.Transpose, tmp_path: Path
+    ) -> None:
+        filename = tmp_path / "temp.tif"
+        im = hopper("L").crop((0, 0, 128, 64))
+        im.save(filename, tiffinfo={274: orientation})
+        with Image.open(filename) as reloaded:
+            assert reloaded.size == (64, 128)
+            assert_image_equal(reloaded, im.transpose(method))
+
     @pytest.mark.parametrize("mode", ("1", "L"))
     def test_photometric(self, mode: str, tmp_path: Path) -> None:
         filename = tmp_path / "temp.tif"

src/PIL/TiffImagePlugin.py

@@ -1316,15 +1316,21 @@ def get_photoshop_blocks(self) -> dict[int, dict[str, bytes]]:
         return blocks
 
     def load(self) -> Image.core.PixelAccess | None:
-        if self.tile and self.use_load_libtiff:
-            return self._load_libtiff()
-        return super().load()
+        if not self.tile:
+            return super().load()
 
-    def load_prepare(self) -> None:
-        if self._im is None:
-            Image._decompression_bomb_check(self._tile_size)
-            self.im = Image.core.new(self.mode, self._tile_size)
-        ImageFile.ImageFile.load_prepare(self)
+        original_size = self._size
+        self._size = self._tile_size
+
+        try:
+            if self.use_load_libtiff:
+                self._load_libtiff()
+                px = Image.Image.load(self)
+            else:
+                px = super().load()
+        finally:
+            self._size = original_size
+        return px
 
     def load_end(self) -> None:
         # allow closing if we're on the first frame, there's no next
@@ -1343,7 +1349,7 @@ def load_end(self) -> None:
         if ExifTags.Base.Orientation in self.tag_v2:
             del self.tag_v2[ExifTags.Base.Orientation]
 
-    def _load_libtiff(self) -> Image.core.PixelAccess | None:
+    def _load_libtiff(self) -> None:
         """Overload method triggered when we detect a compressed tiff
         Calls out to libtiff"""
 
@@ -1436,8 +1442,6 @@ def _load_libtiff(self) -> Image.core.PixelAccess | None:
             msg = f"decoder error {err}"
             raise OSError(msg)
 
-        return Image.Image.load(self)
-
     def _setup(self) -> None:
         """Setup this image object based on current tags"""
 
@@ -1477,6 +1481,7 @@ def _setup(self) -> None:
             msg = "Invalid dimensions"
             raise ValueError(msg)
         self._tile_size = xsize, ysize
+        Image._decompression_bomb_check(self._tile_size)
         orientation = self.tag_v2.get(ExifTags.Base.Orientation)
         if orientation in (5, 6, 7, 8):
             self._size = ysize, xsize