BufrStubImagePlugin.py
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#
# 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 . import Image, ImageFile
_handler = None
def register_handler(handler):
"""
Install application-specific BUFR image handler.
:param handler: Handler object.
"""
global _handler
_handler = handler
# --------------------------------------------------------------------
# Image adapter
def _accept(prefix):
return prefix[:4] == b"BUFR" or prefix[:4] == b"ZCZC"
class BufrStubImageFile(ImageFile.StubImageFile):
format = "BUFR"
format_description = "BUFR"
def _open(self):
offset = self.fp.tell()
if not _accept(self.fp.read(4)):
raise SyntaxError("Not a BUFR file")
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):
return _handler
def _save(im, fp, filename):
if _handler is None or not hasattr("_handler", "save"):
raise IOError("BUFR save handler not installed")
_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")