diff options
Diffstat (limited to 'synapse/rest/media/v1/thumbnailer.py')
| -rw-r--r-- | synapse/rest/media/v1/thumbnailer.py | 71 |
1 files changed, 60 insertions, 11 deletions
diff --git a/synapse/rest/media/v1/thumbnailer.py b/synapse/rest/media/v1/thumbnailer.py index 390491eb83..9b93b9b4f6 100644 --- a/synapse/rest/media/v1/thumbnailer.py +++ b/synapse/rest/media/v1/thumbnailer.py @@ -14,7 +14,8 @@ # limitations under the License. import logging from io import BytesIO -from typing import Tuple +from types import TracebackType +from typing import Optional, Tuple, Type from PIL import Image @@ -45,6 +46,9 @@ class Thumbnailer: Image.MAX_IMAGE_PIXELS = max_image_pixels def __init__(self, input_path: str): + # Have we closed the image? + self._closed = False + try: self.image = Image.open(input_path) except OSError as e: @@ -89,7 +93,8 @@ class Thumbnailer: # Safety: `transpose` takes an int rather than e.g. an IntEnum. # self.transpose_method is set above to be a value in # EXIF_TRANSPOSE_MAPPINGS, and that only contains correct values. - self.image = self.image.transpose(self.transpose_method) # type: ignore[arg-type] + with self.image: + self.image = self.image.transpose(self.transpose_method) # type: ignore[arg-type] self.width, self.height = self.image.size self.transpose_method = None # We don't need EXIF any more @@ -122,9 +127,11 @@ class Thumbnailer: # If the image has transparency, use RGBA instead. if self.image.mode in ["1", "L", "P"]: if self.image.info.get("transparency", None) is not None: - self.image = self.image.convert("RGBA") + with self.image: + self.image = self.image.convert("RGBA") else: - self.image = self.image.convert("RGB") + with self.image: + self.image = self.image.convert("RGB") return self.image.resize((width, height), Image.ANTIALIAS) def scale(self, width: int, height: int, output_type: str) -> BytesIO: @@ -133,8 +140,8 @@ class Thumbnailer: Returns: BytesIO: the bytes of the encoded image ready to be written to disk """ - scaled = self._resize(width, height) - return self._encode_image(scaled, output_type) + with self._resize(width, height) as scaled: + return self._encode_image(scaled, output_type) def crop(self, width: int, height: int, output_type: str) -> BytesIO: """Rescales and crops the image to the given dimensions preserving @@ -151,18 +158,21 @@ class Thumbnailer: BytesIO: the bytes of the encoded image ready to be written to disk """ if width * self.height > height * self.width: + scaled_width = width scaled_height = (width * self.height) // self.width - scaled_image = self._resize(width, scaled_height) crop_top = (scaled_height - height) // 2 crop_bottom = height + crop_top - cropped = scaled_image.crop((0, crop_top, width, crop_bottom)) + crop = (0, crop_top, width, crop_bottom) else: scaled_width = (height * self.width) // self.height - scaled_image = self._resize(scaled_width, height) + scaled_height = height crop_left = (scaled_width - width) // 2 crop_right = width + crop_left - cropped = scaled_image.crop((crop_left, 0, crop_right, height)) - return self._encode_image(cropped, output_type) + crop = (crop_left, 0, crop_right, height) + + with self._resize(scaled_width, scaled_height) as scaled_image: + with scaled_image.crop(crop) as cropped: + return self._encode_image(cropped, output_type) def _encode_image(self, output_image: Image.Image, output_type: str) -> BytesIO: output_bytes_io = BytesIO() @@ -171,3 +181,42 @@ class Thumbnailer: output_image = output_image.convert("RGB") output_image.save(output_bytes_io, fmt, quality=80) return output_bytes_io + + def close(self) -> None: + """Closes the underlying image file. + + Once closed no other functions can be called. + + Can be called multiple times. + """ + + if self._closed: + return + + self._closed = True + + # Since we run this on the finalizer then we need to handle `__init__` + # raising an exception before it can define `self.image`. + image = getattr(self, "image", None) + if image is None: + return + + image.close() + + def __enter__(self) -> "Thumbnailer": + """Make `Thumbnailer` a context manager that calls `close` on + `__exit__`. + """ + return self + + def __exit__( + self, + type: Optional[Type[BaseException]], + value: Optional[BaseException], + traceback: Optional[TracebackType], + ) -> None: + self.close() + + def __del__(self) -> None: + # Make sure we actually do close the image, rather than leak data. + self.close() |