forked from s444420/AL-2020
74 lines
1.5 KiB
Python
74 lines
1.5 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 . 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 OSError("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")
|