mediagoblin/tests/test_exif.py

   1 # GNU MediaGoblin -- federated, autonomous media hosting
   2 # Copyright (C) 2011, 2012 MediaGoblin contributors.  See AUTHORS.
   3 #
   4 # This program is free software: you can redistribute it and/or modify
   5 # it under the terms of the GNU Affero General Public License as published by
   6 # the Free Software Foundation, either version 3 of the License, or
   7 # (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU Affero General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU Affero General Public License
  15 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 import os
  18 try:
  19     from PIL import Image
  20 except ImportError:
  21     import Image
  22
  23 from collections import OrderedDict
  24
  25 from mediagoblin.tools.exif import exif_fix_image_orientation, \
  26     extract_exif, clean_exif, get_gps_data, get_useful
  27 from .resources import GOOD_JPG, EMPTY_JPG, BAD_JPG, GPS_JPG
  28
  29
  30 def assert_in(a, b):
  31     assert a in b, "%r not in %r" % (a, b)
  32
  33
  34 def test_exif_extraction():
  35     '''
  36     Test EXIF extraction from a good image
  37     '''
  38     result = extract_exif(GOOD_JPG)
  39     clean = clean_exif(result)
  40     useful = get_useful(clean)
  41     gps = get_gps_data(result)
  42
  43     # Do we have the result?
  44     assert len(result) >= 50
  45
  46     # Do we have clean data?
  47     assert len(clean) >= 50
  48
  49     # GPS data?
  50     assert gps == {}
  51
  52     # Do we have the "useful" tags?
  53
  54     expected = OrderedDict({'EXIF CVAPattern': {'field_length': 8,
  55                      'field_offset': 26224,
  56                      'field_type': 7,
  57                      'printable': '[0, 2, 0, 2, 1, 2, 0, 1]',
  58                      'tag': 41730,
  59                      'values': [0, 2, 0, 2, 1, 2, 0, 1]},
  60  'EXIF ColorSpace': {'field_length': 2,
  61                      'field_offset': 476,
  62                      'field_type': 3,
  63                      'printable': 'sRGB',
  64                      'tag': 40961,
  65                      'values': [1]},
  66  'EXIF ComponentsConfiguration': {'field_length': 4,
  67                                   'field_offset': 308,
  68                                   'field_type': 7,
  69                                   'printable': 'YCbCr',
  70                                   'tag': 37121,
  71                                   'values': [1, 2, 3, 0]},
  72  'EXIF CompressedBitsPerPixel': {'field_length': 8,
  73                                  'field_offset': 756,
  74                                  'field_type': 5,
  75                                  'printable': u'4',
  76                                  'tag': 37122,
  77                                  'values': [[4, 1]]},
  78  'EXIF Contrast': {'field_length': 2,
  79                    'field_offset': 656,
  80                    'field_type': 3,
  81                    'printable': u'Soft',
  82                    'tag': 41992,
  83                    'values': [1]},
  84  'EXIF CustomRendered': {'field_length': 2,
  85                          'field_offset': 572,
  86                          'field_type': 3,
  87                          'printable': u'Normal',
  88                          'tag': 41985,
  89                          'values': [0]},
  90  'EXIF DateTimeDigitized': {'field_length': 20,
  91                             'field_offset': 736,
  92                             'field_type': 2,
  93                             'printable': u'2011:06:22 12:20:33',
  94                             'tag': 36868,
  95                             'values': u'2011:06:22 12:20:33'},
  96  'EXIF DateTimeOriginal': {'field_length': 20,
  97                            'field_offset': 716,
  98                            'field_type': 2,
  99                            'printable': u'2011:06:22 12:20:33',
 100                            'tag': 36867,
 101                            'values': u'2011:06:22 12:20:33'},
 102  'EXIF DigitalZoomRatio': {'field_length': 8,
 103                            'field_offset': 26232,
 104                            'field_type': 5,
 105                            'printable': u'1',
 106                            'tag': 41988,
 107                            'values': [[1, 1]]},
 108  'EXIF ExifImageLength': {'field_length': 2,
 109                           'field_offset': 500,
 110                           'field_type': 3,
 111                           'printable': u'2592',
 112                           'tag': 40963,
 113                           'values': [2592]},
 114  'EXIF ExifImageWidth': {'field_length': 2,
 115                          'field_offset': 488,
 116                          'field_type': 3,
 117                          'printable': u'3872',
 118                          'tag': 40962,
 119                          'values': [3872]},
 120  'EXIF ExifVersion': {'field_length': 4,
 121                       'field_offset': 272,
 122                       'field_type': 7,
 123                       'printable': u'0221',
 124                       'tag': 36864,
 125                       'values': [48, 50, 50, 49]},
 126  'EXIF ExposureBiasValue': {'field_length': 8,
 127                             'field_offset': 764,
 128                             'field_type': 10,
 129                             'printable': u'0',
 130                             'tag': 37380,
 131                             'values': [[0, 1]]},
 132  'EXIF ExposureMode': {'field_length': 2,
 133                        'field_offset': 584,
 134                        'field_type': 3,
 135                        'printable': u'Manual Exposure',
 136                        'tag': 41986,
 137                        'values': [1]},
 138  'EXIF ExposureProgram': {'field_length': 2,
 139                           'field_offset': 248,
 140                           'field_type': 3,
 141                           'printable': u'Manual',
 142                           'tag': 34850,
 143                           'values': [1]},
 144  'EXIF ExposureTime': {'field_length': 8,
 145                        'field_offset': 700,
 146                        'field_type': 5,
 147                        'printable': u'1/125',
 148                        'tag': 33434,
 149                        'values': [[1, 125]]},
 150  'EXIF FNumber': {'field_length': 8,
 151                   'field_offset': 708,
 152                   'field_type': 5,
 153                   'printable': u'10',
 154                   'tag': 33437,
 155                   'values': [[10, 1]]},
 156  'EXIF FileSource': {'field_length': 1,
 157                      'field_offset': 536,
 158                      'field_type': 7,
 159                      'printable': u'Digital Camera',
 160                      'tag': 41728,
 161                      'values': [3]},
 162  'EXIF Flash': {'field_length': 2,
 163                 'field_offset': 380,
 164                 'field_type': 3,
 165                 'printable': u'Flash did not fire',
 166                 'tag': 37385,
 167                 'values': [0]},
 168  'EXIF FlashPixVersion': {'field_length': 4,
 169                           'field_offset': 464,
 170                           'field_type': 7,
 171                           'printable': u'0100',
 172                           'tag': 40960,
 173                           'values': [48, 49, 48, 48]},
 174  'EXIF FocalLength': {'field_length': 8,
 175                       'field_offset': 780,
 176                       'field_type': 5,
 177                       'printable': u'18',
 178                       'tag': 37386,
 179                       'values': [[18, 1]]},
 180  'EXIF FocalLengthIn35mmFilm': {'field_length': 2,
 181                                 'field_offset': 620,
 182                                 'field_type': 3,
 183                                 'printable': u'27',
 184                                 'tag': 41989,
 185                                 'values': [27]},
 186  'EXIF GainControl': {'field_length': 2,
 187                       'field_offset': 644,
 188                       'field_type': 3,
 189                       'printable': u'None',
 190                       'tag': 41991,
 191                       'values': [0]},
 192  'EXIF ISOSpeedRatings': {'field_length': 2,
 193                           'field_offset': 260,
 194                           'field_type': 3,
 195                           'printable': u'100',
 196                           'tag': 34855,
 197                           'values': [100]},
 198  'EXIF InteroperabilityOffset': {'field_length': 4,
 199                                  'field_offset': 512,
 200                                  'field_type': 4,
 201                                  'printable': u'26240',
 202                                  'tag': 40965,
 203                                  'values': [26240]},
 204  'EXIF LightSource': {'field_length': 2,
 205                       'field_offset': 368,
 206                       'field_type': 3,
 207                       'printable': u'Unknown',
 208                       'tag': 37384,
 209                       'values': [0]},
 210  'EXIF MaxApertureValue': {'field_length': 8,
 211                            'field_offset': 772,
 212                            'field_type': 5,
 213                            'printable': u'18/5',
 214                            'tag': 37381,
 215                            'values': [[18, 5]]},
 216  'EXIF MeteringMode': {'field_length': 2,
 217                        'field_offset': 356,
 218                        'field_type': 3,
 219                        'printable': u'Pattern',
 220                        'tag': 37383,
 221                        'values': [5]},
 222  'EXIF Saturation': {'field_length': 2,
 223                      'field_offset': 668,
 224                      'field_type': 3,
 225                      'printable': u'Normal',
 226                      'tag': 41993,
 227                      'values': [0]},
 228  'EXIF SceneCaptureType': {'field_length': 2,
 229                            'field_offset': 632,
 230                            'field_type': 3,
 231                            'printable': u'Standard',
 232                            'tag': 41990,
 233                            'values': [0]},
 234  'EXIF SceneType': {'field_length': 1,
 235                     'field_offset': 548,
 236                     'field_type': 7,
 237                     'printable': u'Directly Photographed',
 238                     'tag': 41729,
 239                     'values': [1]},
 240  'EXIF SensingMethod': {'field_length': 2,
 241                         'field_offset': 524,
 242                         'field_type': 3,
 243                         'printable': u'One-chip color area',
 244                         'tag': 41495,
 245                         'values': [2]},
 246  'EXIF Sharpness': {'field_length': 2,
 247                     'field_offset': 680,
 248                     'field_type': 3,
 249                     'printable': u'Normal',
 250                     'tag': 41994,
 251                     'values': [0]},
 252  'EXIF SubSecTime': {'field_length': 3,
 253                      'field_offset': 428,
 254                      'field_type': 2,
 255                      'printable': u'10',
 256                      'tag': 37520,
 257                      'values': u'10'},
 258  'EXIF SubSecTimeDigitized': {'field_length': 3,
 259                               'field_offset': 452,
 260                               'field_type': 2,
 261                               'printable': u'10',
 262                               'tag': 37522,
 263                               'values': u'10'},
 264  'EXIF SubSecTimeOriginal': {'field_length': 3,
 265                              'field_offset': 440,
 266                              'field_type': 2,
 267                              'printable': u'10',
 268                              'tag': 37521,
 269                              'values': u'10'},
 270  'EXIF SubjectDistanceRange': {'field_length': 2,
 271                                'field_offset': 692,
 272                                'field_type': 3,
 273                                'printable': u'0',
 274                                'tag': 41996,
 275                                'values': [0]},
 276  'EXIF WhiteBalance': {'field_length': 2,
 277                        'field_offset': 596,
 278                        'field_type': 3,
 279                        'printable': u'Auto',
 280                        'tag': 41987,
 281                        'values': [0]},
 282  'Image DateTime': {'field_length': 20,
 283                     'field_offset': 194,
 284                     'field_type': 2,
 285                     'printable': u'2011:06:22 12:20:33',
 286                     'tag': 306,
 287                     'values': u'2011:06:22 12:20:33'},
 288  'Image ExifOffset': {'field_length': 4,
 289                       'field_offset': 126,
 290                       'field_type': 4,
 291                       'printable': u'214',
 292                       'tag': 34665,
 293                       'values': [214]},
 294  'Image Make': {'field_length': 18,
 295                 'field_offset': 134,
 296                 'field_type': 2,
 297                 'printable': u'NIKON CORPORATION',
 298                 'tag': 271,
 299                 'values': u'NIKON CORPORATION'},
 300  'Image Model': {'field_length': 10,
 301                  'field_offset': 152,
 302                  'field_type': 2,
 303                  'printable': u'NIKON D80',
 304                  'tag': 272,
 305                  'values': u'NIKON D80'},
 306  'Image Orientation': {'field_length': 2,
 307                        'field_offset': 42,
 308                        'field_type': 3,
 309                        'printable': u'Rotated 90 CW',
 310                        'tag': 274,
 311                        'values': [6]},
 312  'Image ResolutionUnit': {'field_length': 2,
 313                           'field_offset': 78,
 314                           'field_type': 3,
 315                           'printable': u'Pixels/Inch',
 316                           'tag': 296,
 317                           'values': [2]},
 318  'Image Software': {'field_length': 15,
 319                     'field_offset': 178,
 320                     'field_type': 2,
 321                     'printable': u'Shotwell 0.9.3',
 322                     'tag': 305,
 323                     'values': u'Shotwell 0.9.3'},
 324  'Image XResolution': {'field_length': 8,
 325                        'field_offset': 162,
 326                        'field_type': 5,
 327                        'printable': u'300',
 328                        'tag': 282,
 329                        'values': [[300, 1]]},
 330  'Image YCbCrPositioning': {'field_length': 2,
 331                             'field_offset': 114,
 332                             'field_type': 3,
 333                             'printable': u'Co-sited',
 334                             'tag': 531,
 335                             'values': [2]},
 336  'Image YResolution': {'field_length': 8,
 337                        'field_offset': 170,
 338                        'field_type': 5,
 339                        'printable': u'300',
 340                        'tag': 283,
 341                        'values': [[300, 1]]},
 342  'Thumbnail Compression': {'field_length': 2,
 343                            'field_offset': 26280,
 344                            'field_type': 3,
 345                            'printable': u'JPEG (old-style)',
 346                            'tag': 259,
 347                            'values': [6]},
 348  'Thumbnail ResolutionUnit': {'field_length': 2,
 349                               'field_offset': 26316,
 350                               'field_type': 3,
 351                               'printable': u'Pixels/Inch',
 352                               'tag': 296,
 353                               'values': [2]},
 354  'Thumbnail XResolution': {'field_length': 8,
 355                            'field_offset': 26360,
 356                            'field_type': 5,
 357                            'printable': u'300',
 358                            'tag': 282,
 359                            'values': [[300, 1]]},
 360  'Thumbnail YCbCrPositioning': {'field_length': 2,
 361                                 'field_offset': 26352,
 362                                 'field_type': 3,
 363                                 'printable': u'Co-sited',
 364                                 'tag': 531,
 365                                 'values': [2]},
 366  'Thumbnail YResolution': {'field_length': 8,
 367                            'field_offset': 26368,
 368                            'field_type': 5,
 369                            'printable': u'300',
 370                            'tag': 283,
 371                            'values': [[300, 1]]}})
 372
 373     for key in expected.keys():
 374         assert useful[key] == expected[key]
 375
 376
 377 def test_exif_image_orientation():
 378     '''
 379     Test image reorientation based on EXIF data
 380     '''
 381     result = extract_exif(GOOD_JPG)
 382
 383     image = exif_fix_image_orientation(
 384         Image.open(GOOD_JPG),
 385         result)
 386
 387     # Are the dimensions correct?
 388     assert image.size in ((428, 640), (640, 428))
 389
 390     # If this pixel looks right, the rest of the image probably will too.
 391     # It seems different values are being seen on different platforms/systems
 392     # as of ccca39f1 it seems we're adding to the list those which are seen.
 393     assert_in(image.getdata()[10000],
 394               ((37, 23, 14), (41, 28, 11), (43, 27, 11))
 395               )
 396
 397
 398 def test_exif_no_exif():
 399     '''
 400     Test an image without exif
 401     '''
 402     result = extract_exif(EMPTY_JPG)
 403     clean = clean_exif(result)
 404     useful = get_useful(clean)
 405     gps = get_gps_data(result)
 406
 407     assert result == {}
 408     assert clean == {}
 409     assert gps == {}
 410     assert useful == {}
 411
 412
 413 def test_exif_bad_image():
 414     '''
 415     Test EXIF extraction from a faithful, but bad image
 416     '''
 417     result = extract_exif(BAD_JPG)
 418     clean = clean_exif(result)
 419     useful = get_useful(clean)
 420     gps = get_gps_data(result)
 421
 422     assert result == {}
 423     assert clean == {}
 424     assert gps == {}
 425     assert useful == {}
 426
 427
 428 def test_exif_gps_data():
 429     '''
 430     Test extractiion of GPS data
 431     '''
 432     result = extract_exif(GPS_JPG)
 433     gps = get_gps_data(result)
 434
 435     assert gps == {
 436         'latitude': 59.336666666666666,
 437         'direction': 25.674046740467404,
 438         'altitude': 37.64365671641791,
 439         'longitude': 18.016166666666667}