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