1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
|
# encoding: utf-8
# Copyright (C) 2021 - 2022 Advanced Micro Devices, Inc. All rights reserved.
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
# This module monkey patches the docx library to add support for Windows Enhanced Metafile images (EMF)
# Put in a local folder and "import docx_emf_patch" to enable EMF support.
from __future__ import absolute_import, division, print_function
import docx
from docx.image.exceptions import UnrecognizedImageError
from docx.image.constants import MIME_TYPE
from docx.image.exceptions import InvalidImageStreamError
from docx.image.helpers import BIG_ENDIAN, StreamReader
from docx.image.image import BaseImageHeader
import struct
def _ImageHeaderFactory(stream):
"""
Return a |BaseImageHeader| subclass instance that knows how to parse the
headers of the image in *stream*.
"""
from docx.image import SIGNATURES
def read_64(stream):
stream.seek(0)
return stream.read(64)
header = read_64(stream)
for cls, offset, signature_bytes in SIGNATURES:
end = offset + len(signature_bytes)
found_bytes = header[offset:end]
if found_bytes == signature_bytes:
return cls.from_stream(stream)
raise UnrecognizedImageError
class Emf(BaseImageHeader):
"""
Image header parser for EMF images
"""
@property
def content_type(self):
"""
MIME content type for this image, unconditionally `image/emf` for
EMF images.
"""
return MIME_TYPE.EMF
@property
def default_ext(self):
"""
Default filename extension, always 'emf' for EMF images.
"""
return 'emf'
@classmethod
def from_stream(cls, stream, filename=None):
"""
Return a |Emf| instance having header properties parsed from image in
*stream*.
"""
"""
@0 DWORD iType; // fixed
@4 DWORD nSize; // var
@8 RECTL rclBounds;
@24 RECTL rclFrame; // .01 millimeter units L T R B
@40 DWORD dSignature; // ENHMETA_SIGNATURE = 0x464D4520
DWORD nVersion;
DWORD nBytes;
DWORD nRecords;
WORD nHandles;
WORD sReserved;
DWORD nDescription;
DWORD offDescription;
DWORD nPalEntries;
SIZEL szlDevice;
SIZEL szlMillimeters;
"""
stream.seek(0)
x = stream.read(40)
stream.seek(0)
iType, nSize = struct.unpack("ii", x[0:8])
rclBounds = struct.unpack("iiii", x[8:24])
rclFrame = struct.unpack("iiii", x[24:40])
dpi = 300
horz_dpi = dpi
vert_dpi = dpi
mmwidth = (rclFrame[2] - rclFrame[0]) / 100.0
mmheight = (rclFrame[3] - rclFrame[1]) / 100.0
px_width = int(mmwidth * dpi * 0.03937008)
px_height = int(mmheight * dpi * 0.03937008)
#1 dot/inch = 0.03937008 pixel/millimeter
return cls(px_width, px_height, horz_dpi, vert_dpi)
docx.image.Emf = Emf
docx.image.constants.MIME_TYPE.EMF = 'image/emf'
docx.image.SIGNATURES = tuple(
list(docx.image.SIGNATURES) + [(Emf, 40, b' EMF')])
docx.image.image._ImageHeaderFactory = _ImageHeaderFactory
|
