diff --git a/Tests/images/multipage_multiple_frame_loop.tiff b/Tests/images/multipage_multiple_frame_loop.tiff new file mode 100644 index 00000000000..b6759b08023 Binary files /dev/null and b/Tests/images/multipage_multiple_frame_loop.tiff differ diff --git a/Tests/images/multipage_out_of_order.tiff b/Tests/images/multipage_out_of_order.tiff new file mode 100644 index 00000000000..1576a549b58 Binary files /dev/null and b/Tests/images/multipage_out_of_order.tiff differ diff --git a/Tests/images/multipage_single_frame_loop.tiff b/Tests/images/multipage_single_frame_loop.tiff new file mode 100644 index 00000000000..26f27c421cd Binary files /dev/null and b/Tests/images/multipage_single_frame_loop.tiff differ diff --git a/Tests/test_file_tiff.py b/Tests/test_file_tiff.py index c24438c4851..dd312d6df6a 100644 --- a/Tests/test_file_tiff.py +++ b/Tests/test_file_tiff.py @@ -301,6 +301,19 @@ def test_multipage_last_frame(self): assert im.size == (20, 20) assert im.convert("RGB").getpixel((0, 0)) == (0, 0, 255) + def test_frame_order(self): + # A frame can't progress to itself after reading + with Image.open("Tests/images/multipage_single_frame_loop.tiff") as im: + assert im.n_frames == 1 + + # A frame can't progress to a frame that has already been read + with Image.open("Tests/images/multipage_multiple_frame_loop.tiff") as im: + assert im.n_frames == 2 + + # Frames don't have to be in sequence + with Image.open("Tests/images/multipage_out_of_order.tiff") as im: + assert im.n_frames == 3 + def test___str__(self): filename = "Tests/images/pil136.tiff" with Image.open(filename) as im: diff --git a/src/PIL/TiffImagePlugin.py b/src/PIL/TiffImagePlugin.py index 5d046761a6a..ed14ec4c7b0 100644 --- a/src/PIL/TiffImagePlugin.py +++ b/src/PIL/TiffImagePlugin.py @@ -1067,7 +1067,12 @@ def _seek(self, frame): self._frame_pos.append(self.__next) logger.debug("Loading tags, location: %s" % self.fp.tell()) self.tag_v2.load(self.fp) - self.__next = self.tag_v2.next + if self.tag_v2.next in self._frame_pos: + # This IFD has already been processed + # Declare this to be the end of the image to prevent an infinite loop + self.__next = 0 + else: + self.__next = self.tag_v2.next if self.__next == 0: self._n_frames = frame + 1 if len(self._frame_pos) == 1: