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- #
- # The Python Imaging Library
- # $Id$
- #
- # WMF stub codec
- #
- # history:
- # 1996-12-14 fl Created
- # 2004-02-22 fl Turned into a stub driver
- # 2004-02-23 fl Added EMF support
- #
- # Copyright (c) Secret Labs AB 1997-2004. All rights reserved.
- # Copyright (c) Fredrik Lundh 1996.
- #
- # See the README file for information on usage and redistribution.
- #
- # WMF/EMF reference documentation:
- # https://winprotocoldoc.blob.core.windows.net/productionwindowsarchives/MS-WMF/[MS-WMF].pdf
- # http://wvware.sourceforge.net/caolan/index.html
- # http://wvware.sourceforge.net/caolan/ora-wmf.html
-
- from __future__ import print_function
-
- from . import Image, ImageFile
- from ._binary import i16le as word, si16le as short, \
- i32le as dword, si32le as _long
- from ._util import py3
-
-
- __version__ = "0.2"
-
- _handler = None
-
- if py3:
- long = int
-
-
- def register_handler(handler):
- """
- Install application-specific WMF image handler.
-
- :param handler: Handler object.
- """
- global _handler
- _handler = handler
-
-
- if hasattr(Image.core, "drawwmf"):
- # install default handler (windows only)
-
- class WmfHandler(object):
-
- def open(self, im):
- im.mode = "RGB"
- self.bbox = im.info["wmf_bbox"]
-
- def load(self, im):
- im.fp.seek(0) # rewind
- return Image.frombytes(
- "RGB", im.size,
- Image.core.drawwmf(im.fp.read(), im.size, self.bbox),
- "raw", "BGR", (im.size[0]*3 + 3) & -4, -1
- )
-
- register_handler(WmfHandler())
-
- #
- # --------------------------------------------------------------------
- # Read WMF file
-
-
- def _accept(prefix):
- return (
- prefix[:6] == b"\xd7\xcd\xc6\x9a\x00\x00" or
- prefix[:4] == b"\x01\x00\x00\x00"
- )
-
-
- ##
- # Image plugin for Windows metafiles.
-
- class WmfStubImageFile(ImageFile.StubImageFile):
-
- format = "WMF"
- format_description = "Windows Metafile"
-
- def _open(self):
-
- # check placable header
- s = self.fp.read(80)
-
- if s[:6] == b"\xd7\xcd\xc6\x9a\x00\x00":
-
- # placeable windows metafile
-
- # get units per inch
- inch = word(s, 14)
-
- # get bounding box
- x0 = short(s, 6)
- y0 = short(s, 8)
- x1 = short(s, 10)
- y1 = short(s, 12)
-
- # normalize size to 72 dots per inch
- size = (x1 - x0) * 72 // inch, (y1 - y0) * 72 // inch
-
- self.info["wmf_bbox"] = x0, y0, x1, y1
-
- self.info["dpi"] = 72
-
- # sanity check (standard metafile header)
- if s[22:26] != b"\x01\x00\t\x00":
- raise SyntaxError("Unsupported WMF file format")
-
- elif dword(s) == 1 and s[40:44] == b" EMF":
- # enhanced metafile
-
- # get bounding box
- x0 = _long(s, 8)
- y0 = _long(s, 12)
- x1 = _long(s, 16)
- y1 = _long(s, 20)
-
- # get frame (in 0.01 millimeter units)
- frame = _long(s, 24), _long(s, 28), _long(s, 32), _long(s, 36)
-
- # normalize size to 72 dots per inch
- size = x1 - x0, y1 - y0
-
- # calculate dots per inch from bbox and frame
- xdpi = 2540 * (x1 - y0) // (frame[2] - frame[0])
- ydpi = 2540 * (y1 - y0) // (frame[3] - frame[1])
-
- self.info["wmf_bbox"] = x0, y0, x1, y1
-
- if xdpi == ydpi:
- self.info["dpi"] = xdpi
- else:
- self.info["dpi"] = xdpi, ydpi
-
- else:
- raise SyntaxError("Unsupported file format")
-
- self.mode = "RGB"
- self._size = size
-
- 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("WMF save handler not installed")
- _handler.save(im, fp, filename)
-
- #
- # --------------------------------------------------------------------
- # Registry stuff
-
-
- Image.register_open(WmfStubImageFile.format, WmfStubImageFile, _accept)
- Image.register_save(WmfStubImageFile.format, _save)
-
- Image.register_extensions(WmfStubImageFile.format, [".wmf", ".emf"])
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