Spaces:
Sleeping
Sleeping
# | |
# The Python Imaging Library | |
# $Id$ | |
# | |
# GRIB 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 GRIB image handler. | |
:param handler: Handler object. | |
""" | |
global _handler | |
_handler = handler | |
# -------------------------------------------------------------------- | |
# Image adapter | |
def _accept(prefix: bytes) -> bool: | |
return prefix[:4] == b"GRIB" and prefix[7] == 1 | |
class GribStubImageFile(ImageFile.StubImageFile): | |
format = "GRIB" | |
format_description = "GRIB" | |
def _open(self) -> None: | |
offset = self.fp.tell() | |
if not _accept(self.fp.read(8)): | |
msg = "Not a GRIB 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 = "GRIB save handler not installed" | |
raise OSError(msg) | |
_handler.save(im, fp, filename) | |
# -------------------------------------------------------------------- | |
# Registry | |
Image.register_open(GribStubImageFile.format, GribStubImageFile, _accept) | |
Image.register_save(GribStubImageFile.format, _save) | |
Image.register_extension(GribStubImageFile.format, ".grib") | |