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
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
|
# -*- coding: utf-8 -*-
from __future__ import absolute_import
from .base import Type
from .isobmff import IsoBmff
class Jpeg(Type):
"""
Implements the JPEG image type matcher.
"""
MIME = 'image/jpeg'
EXTENSION = 'jpg'
def __init__(self):
super(Jpeg, self).__init__(
mime=Jpeg.MIME,
extension=Jpeg.EXTENSION
)
def match(self, buf):
return (len(buf) > 2 and
buf[0] == 0xFF and
buf[1] == 0xD8 and
buf[2] == 0xFF)
class Jpx(Type):
"""
Implements the JPEG2000 image type matcher.
"""
MIME = "image/jpx"
EXTENSION = "jpx"
def __init__(self):
super(Jpx, self).__init__(mime=Jpx.MIME, extension=Jpx.EXTENSION)
def match(self, buf):
return (
len(buf) > 50
and buf[0] == 0x00
and buf[1] == 0x00
and buf[2] == 0x00
and buf[3] == 0x0C
and buf[16:24] == b"ftypjp2 "
)
class Apng(Type):
"""
Implements the APNG image type matcher.
"""
MIME = 'image/apng'
EXTENSION = 'apng'
def __init__(self):
super(Apng, self).__init__(
mime=Apng.MIME,
extension=Apng.EXTENSION
)
def match(self, buf):
if (len(buf) > 8 and
buf[:8] == bytearray([0x89, 0x50, 0x4e, 0x47,
0x0d, 0x0a, 0x1a, 0x0a])):
# cursor in buf, skip already readed 8 bytes
i = 8
while len(buf) > i:
data_length = int.from_bytes(buf[i:i+4], byteorder="big")
i += 4
chunk_type = buf[i:i+4].decode("ascii", errors='ignore')
i += 4
# acTL chunk in APNG should appears first than IDAT
# IEND is end of PNG
if (chunk_type == "IDAT" or chunk_type == "IEND"):
return False
elif (chunk_type == "acTL"):
return True
# move to the next chunk by skipping data and crc (4 bytes)
i += data_length + 4
return False
class Png(Type):
"""
Implements the PNG image type matcher.
"""
MIME = 'image/png'
EXTENSION = 'png'
def __init__(self):
super(Png, self).__init__(
mime=Png.MIME,
extension=Png.EXTENSION
)
def match(self, buf):
return (len(buf) > 3 and
buf[0] == 0x89 and
buf[1] == 0x50 and
buf[2] == 0x4E and
buf[3] == 0x47)
class Gif(Type):
"""
Implements the GIF image type matcher.
"""
MIME = 'image/gif'
EXTENSION = 'gif'
def __init__(self):
super(Gif, self).__init__(
mime=Gif.MIME,
extension=Gif.EXTENSION,
)
def match(self, buf):
return (len(buf) > 2 and
buf[0] == 0x47 and
buf[1] == 0x49 and
buf[2] == 0x46)
class Webp(Type):
"""
Implements the WEBP image type matcher.
"""
MIME = 'image/webp'
EXTENSION = 'webp'
def __init__(self):
super(Webp, self).__init__(
mime=Webp.MIME,
extension=Webp.EXTENSION,
)
def match(self, buf):
return (len(buf) > 13 and
buf[0] == 0x52 and
buf[1] == 0x49 and
buf[2] == 0x46 and
buf[3] == 0x46 and
buf[8] == 0x57 and
buf[9] == 0x45 and
buf[10] == 0x42 and
buf[11] == 0x50 and
buf[12] == 0x56 and
buf[13] == 0x50)
class Cr2(Type):
"""
Implements the CR2 image type matcher.
"""
MIME = 'image/x-canon-cr2'
EXTENSION = 'cr2'
def __init__(self):
super(Cr2, self).__init__(
mime=Cr2.MIME,
extension=Cr2.EXTENSION,
)
def match(self, buf):
return (len(buf) > 9 and
((buf[0] == 0x49 and buf[1] == 0x49 and
buf[2] == 0x2A and buf[3] == 0x0) or
(buf[0] == 0x4D and buf[1] == 0x4D and
buf[2] == 0x0 and buf[3] == 0x2A)) and
buf[8] == 0x43 and buf[9] == 0x52)
class Tiff(Type):
"""
Implements the TIFF image type matcher.
"""
MIME = 'image/tiff'
EXTENSION = 'tif'
def __init__(self):
super(Tiff, self).__init__(
mime=Tiff.MIME,
extension=Tiff.EXTENSION,
)
def match(self, buf):
return (len(buf) > 9 and
((buf[0] == 0x49 and buf[1] == 0x49 and
buf[2] == 0x2A and buf[3] == 0x0) or
(buf[0] == 0x4D and buf[1] == 0x4D and
buf[2] == 0x0 and buf[3] == 0x2A))
and not (buf[8] == 0x43 and buf[9] == 0x52))
class Bmp(Type):
"""
Implements the BMP image type matcher.
"""
MIME = 'image/bmp'
EXTENSION = 'bmp'
def __init__(self):
super(Bmp, self).__init__(
mime=Bmp.MIME,
extension=Bmp.EXTENSION,
)
def match(self, buf):
return (len(buf) > 1 and
buf[0] == 0x42 and
buf[1] == 0x4D)
class Jxr(Type):
"""
Implements the JXR image type matcher.
"""
MIME = 'image/vnd.ms-photo'
EXTENSION = 'jxr'
def __init__(self):
super(Jxr, self).__init__(
mime=Jxr.MIME,
extension=Jxr.EXTENSION,
)
def match(self, buf):
return (len(buf) > 2 and
buf[0] == 0x49 and
buf[1] == 0x49 and
buf[2] == 0xBC)
class Psd(Type):
"""
Implements the PSD image type matcher.
"""
MIME = 'image/vnd.adobe.photoshop'
EXTENSION = 'psd'
def __init__(self):
super(Psd, self).__init__(
mime=Psd.MIME,
extension=Psd.EXTENSION,
)
def match(self, buf):
return (len(buf) > 3 and
buf[0] == 0x38 and
buf[1] == 0x42 and
buf[2] == 0x50 and
buf[3] == 0x53)
class Ico(Type):
"""
Implements the ICO image type matcher.
"""
MIME = 'image/x-icon'
EXTENSION = 'ico'
def __init__(self):
super(Ico, self).__init__(
mime=Ico.MIME,
extension=Ico.EXTENSION,
)
def match(self, buf):
return (len(buf) > 3 and
buf[0] == 0x00 and
buf[1] == 0x00 and
buf[2] == 0x01 and
buf[3] == 0x00)
class Heic(IsoBmff):
"""
Implements the HEIC image type matcher.
"""
MIME = 'image/heic'
EXTENSION = 'heic'
def __init__(self):
super(Heic, self).__init__(
mime=Heic.MIME,
extension=Heic.EXTENSION
)
def match(self, buf):
if not self._is_isobmff(buf):
return False
major_brand, minor_version, compatible_brands = self._get_ftyp(buf)
if major_brand == 'heic':
return True
if major_brand in ['mif1', 'msf1'] and 'heic' in compatible_brands:
return True
return False
class Dcm(Type):
MIME = 'application/dicom'
EXTENSION = 'dcm'
OFFSET = 128
def __init__(self):
super(Dcm, self).__init__(
mime=Dcm.MIME,
extension=Dcm.EXTENSION
)
def match(self, buf):
return (len(buf) > Dcm.OFFSET + 4 and
buf[Dcm.OFFSET + 0] == 0x44 and
buf[Dcm.OFFSET + 1] == 0x49 and
buf[Dcm.OFFSET + 2] == 0x43 and
buf[Dcm.OFFSET + 3] == 0x4D)
class Dwg(Type):
"""Implements the Dwg image type matcher."""
MIME = 'image/vnd.dwg'
EXTENSION = 'dwg'
def __init__(self):
super(Dwg, self).__init__(
mime=Dwg.MIME,
extension=Dwg.EXTENSION
)
def match(self, buf):
return buf[:4] == bytearray([0x41, 0x43, 0x31, 0x30])
class Xcf(Type):
"""Implements the Xcf image type matcher."""
MIME = 'image/x-xcf'
EXTENSION = 'xcf'
def __init__(self):
super(Xcf, self).__init__(
mime=Xcf.MIME,
extension=Xcf.EXTENSION
)
def match(self, buf):
return buf[:10] == bytearray([0x67, 0x69, 0x6d, 0x70, 0x20,
0x78, 0x63, 0x66, 0x20, 0x76])
class Avif(IsoBmff):
"""
Implements the AVIF image type matcher.
"""
MIME = 'image/avif'
EXTENSION = 'avif'
def __init__(self):
super(Avif, self).__init__(
mime=Avif.MIME,
extension=Avif.EXTENSION
)
def match(self, buf):
if not self._is_isobmff(buf):
return False
major_brand, minor_version, compatible_brands = self._get_ftyp(buf)
if major_brand == 'avif':
return True
if major_brand in ['mif1', 'msf1'] and 'avif' in compatible_brands:
return True
return False
|
