test-kivy-app/kivy_venv/lib/python3.11/site-packages/PIL/BufrStubImagePlugin.py
2024-09-15 15:12:16 +03:00

77 lines
1.7 KiB
Python

#
# The Python Imaging Library
# $Id$
#
# BUFR stub adapter
#
# Copyright (c) 1996-2003 by Fredrik Lundh
#
# See the README file for information on usage and redistribution.
#
from __future__ import annotations
from typing import IO
from . import Image, ImageFile
_handler = None
def register_handler(handler: ImageFile.StubHandler | None) -> None:
"""
Install application-specific BUFR image handler.
:param handler: Handler object.
"""
global _handler
_handler = handler
# --------------------------------------------------------------------
# Image adapter
def _accept(prefix: bytes) -> bool:
return prefix[:4] == b"BUFR" or prefix[:4] == b"ZCZC"
class BufrStubImageFile(ImageFile.StubImageFile):
format = "BUFR"
format_description = "BUFR"
def _open(self) -> None:
offset = self.fp.tell()
if not _accept(self.fp.read(4)):
msg = "Not a BUFR file"
raise SyntaxError(msg)
self.fp.seek(offset)
# make something up
self._mode = "F"
self._size = 1, 1
loader = self._load()
if loader:
loader.open(self)
def _load(self) -> ImageFile.StubHandler | None:
return _handler
def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
if _handler is None or not hasattr(_handler, "save"):
msg = "BUFR save handler not installed"
raise OSError(msg)
_handler.save(im, fp, filename)
# --------------------------------------------------------------------
# Registry
Image.register_open(BufrStubImageFile.format, BufrStubImageFile, _accept)
Image.register_save(BufrStubImageFile.format, _save)
Image.register_extension(BufrStubImageFile.format, ".bufr")