TIFF: report correct image size after opening

Tests/test_image_copy.py

@@ -49,5 +49,6 @@ def test_copy_zero() -> None:
 @skip_unless_feature("libtiff")
 def test_deepcopy() -> None:
     with Image.open("Tests/images/g4_orientation_5.tif") as im:
+        assert im.size == (590, 88)
         out = copy.deepcopy(im)
     assert out.size == (590, 88)

Tests/test_image_resize.py

@@ -17,7 +17,6 @@ from .helper import (
     assert_image_equal_tofile,
     assert_image_similar,
     hopper,
-    skip_unless_feature,
 )
 
 
@@ -299,14 +298,6 @@ class TestImageResize:
             with pytest.raises(ValueError):
                 im.resize((10, 10), "unknown")
 
-    @skip_unless_feature("libtiff")
-    def test_load_first(self) -> None:
-        # load() may change the size of the image
-        # Test that resize() is calling it before getting the size
-        with Image.open("Tests/images/g4_orientation_5.tif") as im:
-            im = im.resize((64, 64))
-            assert im.size == (64, 64)
-
     @pytest.mark.parametrize("mode", ("L", "RGB", "I", "F"))
     def test_default_filter_bicubic(self, mode: str) -> None:
         im = hopper(mode)

Tests/test_image_thumbnail.py

@@ -9,7 +9,6 @@ from .helper import (
     assert_image_similar,
     fromstring,
     hopper,
-    skip_unless_feature,
     tostring,
 )
 
@@ -90,22 +89,6 @@ def test_no_resize() -> None:
         im.thumbnail((64, 64))
         assert im.size == (64, 64)
 
-
-@skip_unless_feature("libtiff")
-def test_load_first() -> None:
-    # load() may change the size of the image
-    # Test that thumbnail() is calling it before performing size calculations
-    with Image.open("Tests/images/g4_orientation_5.tif") as im:
-        im.thumbnail((64, 64))
-        assert im.size == (64, 10)
-
-    # Test thumbnail(), without draft(),
-    # on an image that is large enough once load() has changed the size
-    with Image.open("Tests/images/g4_orientation_5.tif") as im:
-        im.thumbnail((590, 88), reducing_gap=None)
-        assert im.size == (590, 88)
-
-
 def test_load_first_unless_jpeg() -> None:
     # Test that thumbnail() still uses draft() for JPEG
     with Image.open("Tests/images/hopper.jpg") as im:

Tests/test_numpy.py

@@ -240,8 +240,9 @@ def test_zero_size() -> None:
 @skip_unless_feature("libtiff")
 def test_load_first() -> None:
     with Image.open("Tests/images/g4_orientation_5.tif") as im:
+        assert im.size == (590, 88)
         a = numpy.array(im)
-        assert a.shape == (88, 590)
+    assert a.shape == (88, 590)
 
 
 def test_bool() -> None:

src/PIL/ImageFile.py

@@ -322,8 +322,9 @@ class ImageFile(Image.Image):
 
     def load_prepare(self) -> None:
         # create image memory if necessary
-        if self._im is None or self.im.mode != self.mode or self.im.size != self.size:
-            self.im = Image.core.new(self.mode, self.size)
+        # use internal _size property for correct tile size
+        if self._im is None or self.im.mode != self.mode or self.im.size != self._size:
+            self.im = Image.core.new(self.mode, self._size)
         # create palette (optional)
         if self.mode == "P":
             Image.Image.load(self)

src/PIL/TiffImagePlugin.py

@@ -1275,6 +1275,13 @@ class TiffImageFile(ImageFile.ImageFile):
             return self._load_libtiff()
         return super().load()
 
+    @property
+    def size(self) -> tuple[int, int]:
+        if hasattr(self, 'tag_v2'):
+            if self.tag_v2.get(ExifTags.Base.Orientation) in (5, 6, 7, 8):
+                return (self._size[1], self._size[0])
+        return self._size
+
     def load_end(self) -> None:
         # allow closing if we're on the first frame, there's no next
         # This is the ImageFile.load path only, libtiff specific below.
@@ -1559,7 +1566,7 @@ class TiffImageFile(ImageFile.ImageFile):
             if STRIPOFFSETS in self.tag_v2:
                 offsets = self.tag_v2[STRIPOFFSETS]
                 h = self.tag_v2.get(ROWSPERSTRIP, ysize)
-                w = self.size[0]
+                w = xsize
             else:
                 # tiled image
                 offsets = self.tag_v2[TILEOFFSETS]
@@ -1593,9 +1600,9 @@ class TiffImageFile(ImageFile.ImageFile):
                     )
                 )
                 x = x + w
-                if x >= self.size[0]:
+                if x >= xsize:
                     x, y = 0, y + h
-                    if y >= self.size[1]:
+                    if y >= ysize:
                         x = y = 0
                         layer += 1
         else: