includes/Exif.php

   1 <?php
   2 if ( !defined( 'MEDIAWIKI' ) ) die();
   3 /**
   4  * @package MediaWiki
   5  * @subpackage Metadata
   6  *
   7  * @author Ævar Arnfjörð Bjarmason <avarab@gmail.com>
   8  * @copyright Copyright © 2005, Ævar Arnfjörð Bjarmason
   9  * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License along
  22  * with this program; if not, write to the Free Software Foundation, Inc.,
  23  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  24  * http://www.gnu.org/copyleft/gpl.html
  25  *
  26  * @link http://exif.org/Exif2-2.PDF The Exif 2.2 specification
  27  * @bug 1555, 1947
  28  */
  29
  30 /**#@+
  31  * Exif tag type definition
  32  */
  33 define('MW_EXIF_BYTE', 1);              # An 8-bit (1-byte) unsigned integer.
  34 define('MW_EXIF_ASCII', 2);             # An 8-bit byte containing one 7-bit ASCII code. The final byte is terminated with NULL.
  35 define('MW_EXIF_SHORT', 3);             # A 16-bit (2-byte) unsigned integer.
  36 define('MW_EXIF_LONG', 4);              # A 32-bit (4-byte) unsigned integer.
  37 define('MW_EXIF_RATIONAL', 5);          # Two LONGs. The first LONG is the numerator and the second LONG expresses the denominator
  38 define('MW_EXIF_UNDEFINED', 7);         # An 8-bit byte that can take any value depending on the field definition
  39 define('MW_EXIF_SLONG', 9);             # A 32-bit (4-byte) signed integer (2's complement notation),
  40 define('MW_EXIF_SRATIONAL', 10);        # Two SLONGs. The first SLONG is the numerator and the second SLONG is the denominator.
  41 /**#@-*/
  42
  43
  44 /**
  45  * @package MediaWiki
  46  * @subpackage Metadata
  47  */
  48 class Exif {
  49         /**#@+
  50          * @var array
  51          * @access private
  52          */
  53
  54         /**
  55          * Exif tags grouped by category, the tagname itself is the key and the type
  56          * is the value, in the case of more than one possible value type they are
  57          * seperated by commas.
  58          */
  59         var $mExifTags;
  60
  61         /**
  62          * A one dimentional array of all Exif tags
  63          */
  64         var $mFlatExifTags;
  65
  66         /**
  67          * The raw Exif data returned by exif_read_data()
  68          */
  69         var $mRawExifData;
  70
  71         /**
  72          * A Filtered version of $mRawExifData that has been pruned of invalid
  73          * tags and tags that contain content they shouldn't contain according
  74          * to the Exif specification
  75          */
  76         var $mFilteredExifData;
  77
  78         /**
  79          * Filtered and formatted Exif data, see FormatExif::getFormattedData()
  80          */
  81         var $mFormattedExifData;
  82
  83         /**#@-*/
  84
  85         /**
  86          * The private log to log to
  87          *
  88          * @var string
  89          * @access private
  90          */
  91         var $log = 'exif';
  92
  93         /**
  94          * Constructor
  95          *
  96          * @param string $file
  97          */
  98         function Exif( $file ) {
  99                 /**
 100                  * Page numbers here refer to pages in the EXIF 2.2 standard
 101                  *
 102                  * @link http://exif.org/Exif2-2.PDF The Exif 2.2 specification
 103                  */
 104                 $this->mExifTags = array(
 105                         # TIFF Rev. 6.0 Attribute Information (p22)
 106                         'tiff' => array(
 107                                 # Tags relating to image structure
 108                                 'structure' => array(
 109                                         'ImageWidth' => MW_EXIF_SHORT.','.MW_EXIF_LONG,         # Image width
 110                                         'ImageLength' => MW_EXIF_SHORT.','.MW_EXIF_LONG,        # Image height
 111                                         'BitsPerSample' => MW_EXIF_SHORT,                       # Number of bits per component
 112                                         # "When a primary image is JPEG compressed, this designation is not"
 113                                         # "necessary and is omitted." (p23)
 114                                         'Compression' => MW_EXIF_SHORT,                         # Compression scheme #p23
 115                                         'PhotometricInterpretation' => MW_EXIF_SHORT,           # Pixel composition #p23
 116                                         'Orientation' => MW_EXIF_SHORT,                         # Orientation of image #p24
 117                                         'SamplesPerPixel' => MW_EXIF_SHORT,                     # Number of components
 118                                         'PlanarConfiguration' => MW_EXIF_SHORT,                 # Image data arrangement #p24
 119                                         'YCbCrSubSampling' => MW_EXIF_SHORT,                    # Subsampling ratio of Y to C #p24
 120                                         'YCbCrPositioning' => MW_EXIF_SHORT,                    # Y and C positioning #p24-25
 121                                         'XResolution' => MW_EXIF_RATIONAL,                      # Image resolution in width direction
 122                                         'YResolution' => MW_EXIF_RATIONAL,                      # Image resolution in height direction
 123                                         'ResolutionUnit' => MW_EXIF_SHORT,                      # Unit of X and Y resolution #(p26)
 124                                 ),
 125
 126                                 # Tags relating to recording offset
 127                                 'offset' => array(
 128                                         'StripOffsets' => MW_EXIF_SHORT.','.MW_EXIF_LONG,                       # Image data location
 129                                         'RowsPerStrip' => MW_EXIF_SHORT.','.MW_EXIF_LONG,                       # Number of rows per strip
 130                                         'StripByteCounts' => MW_EXIF_SHORT.','.MW_EXIF_LONG,                    # Bytes per compressed strip
 131                                         'JPEGInterchangeFormat' => MW_EXIF_SHORT.','.MW_EXIF_LONG,              # Offset to JPEG SOI
 132                                         'JPEGInterchangeFormatLength' => MW_EXIF_SHORT.','.MW_EXIF_LONG,        # Bytes of JPEG data
 133                                 ),
 134
 135                                 # Tags relating to image data characteristics
 136                                 'characteristics' => array(
 137                                         'TransferFunction' => MW_EXIF_SHORT,            # Transfer function
 138                                         'WhitePoint' => MW_EXIF_RATIONAL,               # White point chromaticity
 139                                         'PrimaryChromaticities' => MW_EXIF_RATIONAL,    # Chromaticities of primarities
 140                                         'YCbCrCoefficients' => MW_EXIF_RATIONAL,        # Color space transformation matrix coefficients #p27
 141                                         'ReferenceBlackWhite' => MW_EXIF_RATIONAL       # Pair of black and white reference values
 142                                 ),
 143
 144                                 # Other tags
 145                                 'other' => array(
 146                                         'DateTime' => MW_EXIF_ASCII,            # File change date and time
 147                                         'ImageDescription' => MW_EXIF_ASCII,    # Image title
 148                                         'Make' => MW_EXIF_ASCII,                # Image input equipment manufacturer
 149                                         'Model' => MW_EXIF_ASCII,               # Image input equipment model
 150                                         'Software' => MW_EXIF_ASCII,            # Software used
 151                                         'Artist' => MW_EXIF_ASCII,              # Person who created the image
 152                                         'Copyright' => MW_EXIF_ASCII,           # Copyright holder
 153                                 ),
 154                         ),
 155
 156                         # Exif IFD Attribute Information (p30-31)
 157                         'exif' => array(
 158                                 # Tags relating to version
 159                                 'version' => array(
 160                                         # TODO: NOTE: Nonexistence of this field is taken to mean nonconformance
 161                                         # to the EXIF 2.1 AND 2.2 standards
 162                                         'ExifVersion' => MW_EXIF_UNDEFINED,     # Exif version
 163                                         'FlashpixVersion' => MW_EXIF_UNDEFINED, # Supported Flashpix version #p32
 164                                 ),
 165
 166                                 # Tags relating to Image Data Characteristics
 167                                 'characteristics' => array(
 168                                         'ColorSpace' => MW_EXIF_SHORT,          # Color space information #p32
 169                                 ),
 170
 171                                 # Tags relating to image configuration
 172                                 'configuration' => array(
 173                                         'ComponentsConfiguration' => MW_EXIF_UNDEFINED,         # Meaning of each component #p33
 174                                         'CompressedBitsPerPixel' => MW_EXIF_RATIONAL,           # Image compression mode
 175                                         'PixelYDimension' => MW_EXIF_SHORT.','.MW_EXIF_LONG,    # Valid image width
 176                                         'PixelXDimension' => MW_EXIF_SHORT.','.MW_EXIF_LONG,    # Valind image height
 177                                 ),
 178
 179                                 # Tags relating to related user information
 180                                 'user' => array(
 181                                         'MakerNote' => MW_EXIF_UNDEFINED,                       # Manufacturer notes
 182                                         'UserComment' => MW_EXIF_UNDEFINED,                     # User comments #p34
 183                                 ),
 184
 185                                 # Tags relating to related file information
 186                                 'related' => array(
 187                                         'RelatedSoundFile' => MW_EXIF_ASCII,                    # Related audio file
 188                                 ),
 189
 190                                 # Tags relating to date and time
 191                                 'dateandtime' => array(
 192                                         'DateTimeOriginal' => MW_EXIF_ASCII,                    # Date and time of original data generation #p36
 193                                         'DateTimeDigitized' => MW_EXIF_ASCII,                   # Date and time of original data generation
 194                                         'SubSecTime' => MW_EXIF_ASCII,                          # DateTime subseconds
 195                                         'SubSecTimeOriginal' => MW_EXIF_ASCII,                  # DateTimeOriginal subseconds
 196                                         'SubSecTimeDigitized' => MW_EXIF_ASCII,                 # DateTimeDigitized subseconds
 197                                 ),
 198
 199                                 # Tags relating to picture-taking conditions (p31)
 200                                 'conditions' => array(
 201                                         'ExposureTime' => MW_EXIF_RATIONAL,                     # Exposure time
 202                                         'FNumber' => MW_EXIF_RATIONAL,                          # F Number
 203                                         'ExposureProgram' => MW_EXIF_SHORT,                     # Exposure Program #p38
 204                                         'SpectralSensitivity' => MW_EXIF_ASCII,                 # Spectral sensitivity
 205                                         'ISOSpeedRatings' => MW_EXIF_SHORT,                     # ISO speed rating
 206                                         'OECF' => MW_EXIF_UNDEFINED,                            # Optoelectronic conversion factor
 207                                         'ShutterSpeedValue' => MW_EXIF_SRATIONAL,               # Shutter speed
 208                                         'ApertureValue' => MW_EXIF_RATIONAL,                    # Aperture
 209                                         'BrightnessValue' => MW_EXIF_SRATIONAL,                 # Brightness
 210                                         'ExposureBiasValue' => MW_EXIF_SRATIONAL,               # Exposure bias
 211                                         'MaxApertureValue' => MW_EXIF_RATIONAL,                 # Maximum land aperture
 212                                         'SubjectDistance' => MW_EXIF_RATIONAL,                  # Subject distance
 213                                         'MeteringMode' => MW_EXIF_SHORT,                        # Metering mode #p40
 214                                         'LightSource' => MW_EXIF_SHORT,                         # Light source #p40-41
 215                                         'Flash' => MW_EXIF_SHORT,                               # Flash #p41-42
 216                                         'FocalLength' => MW_EXIF_RATIONAL,                      # Lens focal length
 217                                         'SubjectArea' => MW_EXIF_SHORT,                         # Subject area
 218                                         'FlashEnergy' => MW_EXIF_RATIONAL,                      # Flash energy
 219                                         'SpatialFrequencyResponse' => MW_EXIF_UNDEFINED,        # Spatial frequency response
 220                                         'FocalPlaneXResolution' => MW_EXIF_RATIONAL,            # Focal plane X resolution
 221                                         'FocalPlaneYResolution' => MW_EXIF_RATIONAL,            # Focal plane Y resolution
 222                                         'FocalPlaneResolutionUnit' => MW_EXIF_SHORT,            # Focal plane resolution unit #p46
 223                                         'SubjectLocation' => MW_EXIF_SHORT,                     # Subject location
 224                                         'ExposureIndex' => MW_EXIF_RATIONAL,                    # Exposure index
 225                                         'SensingMethod' => MW_EXIF_SHORT,                       # Sensing method #p46
 226                                         'FileSource' => MW_EXIF_UNDEFINED,                      # File source #p47
 227                                         'SceneType' => MW_EXIF_UNDEFINED,                       # Scene type #p47
 228                                         'CFAPattern' => MW_EXIF_UNDEFINED,                      # CFA pattern
 229                                         'CustomRendered' => MW_EXIF_SHORT,                      # Custom image processing #p48
 230                                         'ExposureMode' => MW_EXIF_SHORT,                        # Exposure mode #p48
 231                                         'WhiteBalance' => MW_EXIF_SHORT,                        # White Balance #p49
 232                                         'DigitalZoomRatio' => MW_EXIF_RATIONAL,                 # Digital zoom ration
 233                                         'FocalLengthIn35mmFilm' => MW_EXIF_SHORT,               # Focal length in 35 mm film
 234                                         'SceneCaptureType' => MW_EXIF_SHORT,                    # Scene capture type #p49
 235                                         'GainControl' => MW_EXIF_RATIONAL,                      # Scene control #p49-50
 236                                         'Contrast' => MW_EXIF_SHORT,                            # Contrast #p50
 237                                         'Saturation' => MW_EXIF_SHORT,                          # Saturation #p50
 238                                         'Sharpness' => MW_EXIF_SHORT,                           # Sharpness #p50
 239                                         'DeviceSettingDescription' => MW_EXIF_UNDEFINED,        # Desice settings description
 240                                         'SubjectDistanceRange' => MW_EXIF_SHORT,                # Subject distance range #p51
 241                                 ),
 242
 243                                 'other' => array(
 244                                         'ImageUniqueID' => MW_EXIF_ASCII,       # Unique image ID
 245                                 ),
 246                         ),
 247
 248                         # GPS Attribute Information (p52)
 249                         'gps' => array(
 250                                 'GPSVersionID' => MW_EXIF_BYTE,                 # GPS tag version
 251                                 'GPSLatitudeRef' => MW_EXIF_ASCII,              # North or South Latitude #p52-53
 252                                 'GPSLatitude' => MW_EXIF_RATIONAL,              # Latitude
 253                                 'GPSLongitudeRef' => MW_EXIF_ASCII,             # East or West Longitude #p53
 254                                 'GPSLongitude' => MW_EXIF_RATIONAL,             # Longitude
 255                                 'GPSAltitudeRef' => MW_EXIF_BYTE,               # Altitude reference
 256                                 'GPSAltitude' => MW_EXIF_RATIONAL,              # Altitude
 257                                 'GPSTimeStamp' => MW_EXIF_RATIONAL,             # GPS time (atomic clock)
 258                                 'GPSSatellites' => MW_EXIF_ASCII,               # Satellites used for measurement
 259                                 'GPSStatus' => MW_EXIF_ASCII,                   # Receiver status #p54
 260                                 'GPSMeasureMode' => MW_EXIF_ASCII,              # Measurement mode #p54-55
 261                                 'GPSDOP' => MW_EXIF_RATIONAL,                   # Measurement precision
 262                                 'GPSSpeedRef' => MW_EXIF_ASCII,                 # Speed unit #p55
 263                                 'GPSSpeed' => MW_EXIF_RATIONAL,                 # Speed of GPS receiver
 264                                 'GPSTrackRef' => MW_EXIF_ASCII,                 # Reference for direction of movement #p55
 265                                 'GPSTrack' => MW_EXIF_RATIONAL,                 # Direction of movement
 266                                 'GPSImgDirectionRef' => MW_EXIF_ASCII,          # Reference for direction of image #p56
 267                                 'GPSImgDirection' => MW_EXIF_RATIONAL,          # Direction of image
 268                                 'GPSMapDatum' => MW_EXIF_ASCII,                 # Geodetic survey data used
 269                                 'GPSDestLatitudeRef' => MW_EXIF_ASCII,          # Reference for latitude of destination #p56
 270                                 'GPSDestLatitude' => MW_EXIF_RATIONAL,          # Latitude destination
 271                                 'GPSDestLongitudeRef' => MW_EXIF_ASCII,         # Reference for longitude of destination #p57
 272                                 'GPSDestLongitude' => MW_EXIF_RATIONAL,         # Longitude of destination
 273                                 'GPSDestBearingRef' => MW_EXIF_ASCII,           # Reference for bearing of destination #p57
 274                                 'GPSDestBearing' => MW_EXIF_RATIONAL,           # Bearing of destination
 275                                 'GPSDestDistanceRef' => MW_EXIF_ASCII,          # Reference for distance to destination #p57-58
 276                                 'GPSDestDistance' => MW_EXIF_RATIONAL,          # Distance to destination
 277                                 'GPSProcessingMethod' => MW_EXIF_UNDEFINED,     # Name of GPS processing method
 278                                 'GPSAreaInformation' => MW_EXIF_UNDEFINED,      # Name of GPS area
 279                                 'GPSDateStamp' => MW_EXIF_ASCII,                # GPS date
 280                                 'GPSDifferential' => MW_EXIF_SHORT,             # GPS differential correction
 281                         ),
 282                 );
 283
 284                 $basename = basename( $file );
 285
 286                 $this->makeFlatExifTags();
 287
 288                 $this->debugFile( $basename, __FUNCTION__, true );
 289                 wfSuppressWarnings();
 290                 $data = exif_read_data( $file );
 291                 wfRestoreWarnings();
 292                 /**
 293                  * exif_read_data() will return false on invalid input, such as
 294                  * when somebody uploads a file called something.jpeg
 295                  * containing random gibberish.
 296                  */
 297                 $this->mRawExifData = $data ? $data : array();
 298
 299                 $this->makeFilteredData();
 300                 $this->makeFormattedData();
 301
 302                 $this->debugFile( $basename, __FUNCTION__, false );
 303         }
 304
 305         /**#@+
 306          * @access private
 307          */
 308         /**
 309          * Generate a flat list of the exif tags
 310          */
 311         function makeFlatExifTags() {
 312                 $this->extractTags( $this->mExifTags );
 313         }
 314
 315         /**
 316          * A recursing extractor function used by makeFlatExifTags()
 317          *
 318          * Note: This used to use an array_walk function, but it made PHP5
 319          * segfault, see `cvs diff -u -r 1.4 -r 1.5 Exif.php`
 320          */
 321         function extractTags( &$tagset ) {
 322                 foreach( $tagset as $key => $val ) {
 323                         if( is_array( $val ) ) {
 324                                 $this->extractTags( $val );
 325                         } else {
 326                                 $this->mFlatExifTags[$key] = $val;
 327                         }
 328                 }
 329         }
 330
 331         /**
 332          * Make $this->mFilteredExifData
 333          */
 334         function makeFilteredData() {
 335                 $this->mFilteredExifData = $this->mRawExifData;
 336
 337                 foreach( $this->mFilteredExifData as $k => $v ) {
 338                         if ( !in_array( $k, array_keys( $this->mFlatExifTags ) ) ) {
 339                                 $this->debug( $v, __FUNCTION__, "'$k' is not a valid Exif tag" );
 340                                 unset( $this->mFilteredExifData[$k] );
 341                         }
 342                 }
 343
 344                 foreach( $this->mFilteredExifData as $k => $v ) {
 345                         if ( !$this->validate($k, $v) ) {
 346                                 $this->debug( $v, __FUNCTION__, "'$k' contained invalid data" );
 347                                 unset( $this->mFilteredExifData[$k] );
 348                         }
 349                 }
 350         }
 351
 352         function makeFormattedData( $data = null ) {
 353                 $format = new FormatExif( $this->getFilteredData() );
 354                 $this->mFormattedExifData = $format->getFormattedData();
 355         }
 356         /**#@-*/
 357
 358         /**#@+
 359          * @return array
 360          */
 361         /**
 362          * Get $this->mRawExifData
 363          */
 364         function getData() {
 365                 return $this->mRawExifData;
 366         }
 367
 368         /**
 369          * Get $this->mFilteredExifData
 370          */
 371         function getFilteredData() {
 372                 return $this->mFilteredExifData;
 373         }
 374
 375         /**
 376          * Get $this->mFormattedExifData
 377          */
 378         function getFormattedData() {
 379                 return $this->mFormattedExifData;
 380         }
 381         /**#@-*/
 382
 383         /**
 384          * The version of the output format
 385          *
 386          * Before the actual metadata information is saved in the database we
 387          * strip some of it since we don't want to save things like thumbnails
 388          * which usually accompany Exif data. This value gets saved in the
 389          * database along with the actual Exif data, and if the version in the
 390          * database doesn't equal the value returned by this function the Exif
 391          * data is regenerated.
 392          *
 393          * @return int
 394          */
 395         function version() {
 396                 return 1; // We don't need no bloddy constants!
 397         }
 398
 399         /**#@+
 400          * Validates if a tag value is of the type it should be according to the Exif spec
 401          *
 402          * @access private
 403          *
 404          * @param mixed $in The input value to check
 405          * @return bool
 406          */
 407         function isByte( $in ) {
 408                 if ( sprintf('%d', $in) == $in && $in >= 0 && $in <= 255 ) {
 409                         $this->debug( $in, __FUNCTION__, true );
 410                         return true;
 411                 } else {
 412                         $this->debug( $in, __FUNCTION__, false );
 413                         return false;
 414                 }
 415         }
 416
 417         function isASCII( $in ) {
 418                 if ( preg_match( "/[^\x0a\x20-\x7e]/", $in ) ) {
 419                         $this->debug( $in, __FUNCTION__, 'found a character not in our whitelist' );
 420                         return false;
 421                 }
 422
 423                 if ( preg_match( "/^\s*$/", $in ) ) {
 424                         $this->debug( $in, __FUNCTION__, 'input consisted solely of whitespace' );
 425                         return false;
 426                 }
 427
 428                 return true;
 429         }
 430
 431         function isShort( $in ) {
 432                 if ( sprintf('%d', $in) == $in && $in >= 0 && $in <= 65536 ) {
 433                         $this->debug( $in, __FUNCTION__, true );
 434                         return true;
 435                 } else {
 436                         $this->debug( $in, __FUNCTION__, false );
 437                         return false;
 438                 }
 439         }
 440
 441         function isLong( $in ) {
 442                 if ( sprintf('%d', $in) == $in && $in >= 0 && $in <= 4294967296 ) {
 443                         $this->debug( $in, __FUNCTION__, true );
 444                         return true;
 445                 } else {
 446                         $this->debug( $in, __FUNCTION__, false );
 447                         return false;
 448                 }
 449         }
 450
 451         function isRational( $in ) {
 452                 if ( @preg_match( "/^(\d+)\/(\d+[1-9]|[1-9]\d*)$/", $in, $m ) ) { # Avoid division by zero
 453                         return $this->isLong( $m[1] ) && $this->isLong( $m[2] );
 454                 } else {
 455                         $this->debug( $in, __FUNCTION__, 'fed a non-fraction value' );
 456                         return false;
 457                 }
 458         }
 459
 460         function isUndefined( $in ) {
 461                 if ( preg_match( "/^\d{4}$/", $in ) ) { // Allow ExifVersion and FlashpixVersion
 462                         $this->debug( $in, __FUNCTION__, true );
 463                         return true;
 464                 } else {
 465                         $this->debug( $in, __FUNCTION__, false );
 466                         return false;
 467                 }
 468         }
 469
 470         function isSlong( $in ) {
 471                 if ( $this->isLong( abs( $in ) ) ) {
 472                         $this->debug( $in, __FUNCTION__, true );
 473                         return true;
 474                 } else {
 475                         $this->debug( $in, __FUNCTION__, false );
 476                         return false;
 477                 }
 478         }
 479
 480         function isSrational( $in ) {
 481                 if ( preg_match( "/^(\d+)\/(\d+[1-9]|[1-9]\d*)$/", $in, $m ) ) { # Avoid division by zero
 482                         return $this->isSlong( $m[0] ) && $this->isSlong( $m[1] );
 483                 } else {
 484                         $this->debug( $in, __FUNCTION__, 'fed a non-fraction value' );
 485                         return false;
 486                 }
 487         }
 488         /**#@-*/
 489
 490         /**
 491          * Validates if a tag has a legal value according to the Exif spec
 492          *
 493          * @access private
 494          *
 495          * @param string $tag The tag to check
 496          * @param mixed  $val The value of the tag
 497          * @return bool
 498          */
 499         function validate( $tag, $val ) {
 500                 $debug = "tag is '$tag'";
 501                 // Fucks up if not typecast
 502                 switch( (string)$this->mFlatExifTags[$tag] ) {
 503                         case (string)MW_EXIF_BYTE:
 504                                 $this->debug( $val, __FUNCTION__, $debug );
 505                                 return $this->isByte( $val );
 506                         case (string)MW_EXIF_ASCII:
 507                                 $this->debug( $val, __FUNCTION__, $debug );
 508                                 return $this->isASCII( $val );
 509                         case (string)MW_EXIF_SHORT:
 510                                 $this->debug( $val, __FUNCTION__, $debug );
 511                                 return $this->isShort( $val );
 512                         case (string)MW_EXIF_LONG:
 513                                 $this->debug( $val, __FUNCTION__, $debug );
 514                                 return $this->isLong( $val );
 515                         case (string)MW_EXIF_RATIONAL:
 516                                 $this->debug( $val, __FUNCTION__, $debug );
 517                                 return $this->isRational( $val );
 518                         case (string)MW_EXIF_UNDEFINED:
 519                                 $this->debug( $val, __FUNCTION__, $debug );
 520                                 return $this->isUndefined( $val );
 521                         case (string)MW_EXIF_SLONG:
 522                                 $this->debug( $val, __FUNCTION__, $debug );
 523                                 return $this->isSlong( $val );
 524                         case (string)MW_EXIF_SRATIONAL:
 525                                 $this->debug( $val, __FUNCTION__, $debug );
 526                                 return $this->isSrational( $val );
 527                         case (string)MW_EXIF_SHORT.','.MW_EXIF_LONG:
 528                                 $this->debug( $val, __FUNCTION__, $debug );
 529                                 return $this->isShort( $val ) || $this->isLong( $val );
 530                         default:
 531                                 $this->debug( $val, __FUNCTION__, "The tag '$tag' is unknown" );
 532                                 return false;
 533                 }
 534         }
 535
 536         /**
 537          * Conviniance function for debugging output
 538          *
 539          * @access private
 540          *
 541          * @param mixed $in
 542          * @param string $fname
 543          * @param mixed $action
 544          */
 545          function debug( $in, $fname, $action = null ) {
 546                 $type = gettype( $in );
 547                 $class = ucfirst( __CLASS__ );
 548                 if ( $type === 'array' )
 549                         $in = print_r( $in, true );
 550
 551                 if ( $action === true )
 552                         wfDebugLog( $this->log, "$class::$fname: accepted: '$in' (type: $type)\n");
 553                 elseif ( $action === false )
 554                         wfDebugLog( $this->log, "$class::$fname: rejected: '$in' (type: $type)\n");
 555                 elseif ( $action === null )
 556                         wfDebugLog( $this->log, "$class::$fname: input was: '$in' (type: $type)\n");
 557                 else
 558                         wfDebugLog( $this->log, "$class::$fname: $action (type: $type; content: '$in')\n");
 559         }
 560
 561         /**
 562          * Conviniance function for debugging output
 563          *
 564          * @access private
 565          *
 566          * @param string $basename The name of the file being processed
 567          * @paran string $fname The name of the function calling this function
 568          * @param bool $bool $io Specify whether we're beginning or ending
 569          */
 570         function debugFile( $basename, $fname, $io ) {
 571                 $class = ucfirst( __CLASS__ );
 572                 if ( $io )
 573                         wfDebugLog( $this->log, "$class::$fname: begin processing: '$basename'\n" );
 574                 else
 575                         wfDebugLog( $this->log, "$class::$fname: end processing: '$basename'\n" );
 576         }
 577
 578 }
 579
 580 /**
 581  * @package MediaWiki
 582  * @subpackage Metadata
 583  */
 584 class FormatExif {
 585         /**
 586          * The Exif data to format
 587          *
 588          * @var array
 589          * @access private
 590          */
 591         var $mExif;
 592
 593         /**
 594          * Constructor
 595          *
 596          * @param array $exif The Exif data to format ( as returned by
 597          *                    Exif::getFilteredData() )
 598          */
 599         function FormatExif( $exif ) {
 600                 $this->mExif = $exif;
 601         }
 602
 603         /**
 604          * Numbers given by Exif user agents are often magical, that is they
 605          * should be replaced by a detailed explanation depending on their
 606          * value which most of the time are plain integers. This function
 607          * formats Exif values into human readable form.
 608          *
 609          * @return array
 610          */
 611         function getFormattedData() {
 612                 global $wgLang;
 613
 614                 $tags =& $this->mExif;
 615
 616                 $resolutionunit = !isset( $tags['ResolutionUnit'] ) || $tags['ResolutionUnit'] == 2 ? 2 : 3;
 617                 unset( $tags['ResolutionUnit'] );
 618
 619                 foreach( $tags as $tag => $val ) {
 620                         switch( $tag ) {
 621                         case 'Compression':
 622                                 switch( $val ) {
 623                                 case 1: case 6:
 624                                         $tags[$tag] = $this->msg( $tag, $val );
 625                                         break;
 626                                 default:
 627                                         $tags[$tag] = $val;
 628                                         break;
 629                                 }
 630                                 break;
 631
 632                         case 'PhotometricInterpretation':
 633                                 switch( $val ) {
 634                                 case 2: case 6:
 635                                         $tags[$tag] = $this->msg( $tag, $val );
 636                                         break;
 637                                 default:
 638                                         $tags[$tag] = $val;
 639                                         break;
 640                                 }
 641                                 break;
 642
 643                         case 'Orientation':
 644                                 switch( $val ) {
 645                                 case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 8:
 646                                         $tags[$tag] = $this->msg( $tag, $val );
 647                                         break;
 648                                 default:
 649                                         $tags[$tag] = $val;
 650                                         break;
 651                                 }
 652                                 break;
 653
 654                         case 'PlanarConfiguration':
 655                                 switch( $val ) {
 656                                 case 1: case 2:
 657                                         $tags[$tag] = $this->msg( $tag, $val );
 658                                         break;
 659                                 default:
 660                                         $tags[$tag] = $val;
 661                                         break;
 662                                 }
 663                                 break;
 664
 665                         // TODO: YCbCrSubSampling
 666                         // TODO: YCbCrPositioning
 667
 668                         case 'XResolution':
 669                         case 'YResolution':
 670                                 switch( $resolutionunit ) {
 671                                         case 2:
 672                                                 $tags[$tag] = $this->msg( 'XYResolution', 'i', $this->formatNum( $val ) );
 673                                                 break;
 674                                         case 3:
 675                                                 $this->msg( 'XYResolution', 'c', $this->formatNum( $val ) );
 676                                                 break;
 677                                         default:
 678                                                 $tags[$tag] = $val;
 679                                                 break;
 680                                 }
 681                                 break;
 682
 683                         // TODO: YCbCrCoefficients  #p27 (see annex E)
 684                         case 'ExifVersion': case 'FlashpixVersion':
 685                                 $tags[$tag] = "$val"/100;
 686                                 break;
 687
 688                         case 'ColorSpace':
 689                                 switch( $val ) {
 690                                 case 1: case 'FFFF.H':
 691                                         $tags[$tag] = $this->msg( $tag, $val );
 692                                         break;
 693                                 default:
 694                                         $tags[$tag] = $val;
 695                                         break;
 696                                 }
 697                                 break;
 698
 699                         case 'ComponentsConfiguration':
 700                                 switch( $val ) {
 701                                 case 0: case 1: case 2: case 3: case 4: case 5: case 6:
 702                                         $tags[$tag] = $this->msg( $tag, $val );
 703                                         break;
 704                                 default:
 705                                         $tags[$tag] = $val;
 706                                         break;
 707                                 }
 708                                 break;
 709
 710                         case 'DateTime':
 711                         case 'DateTimeOriginal':
 712                         case 'DateTimeDigitized':
 713                                 $tags[$tag] = $wgLang->timeanddate( wfTimestamp(TS_MW, $val) );
 714                                 break;
 715
 716                         case 'ExposureProgram':
 717                                 switch( $val ) {
 718                                 case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 8:
 719                                         $tags[$tag] = $this->msg( $tag, $val );
 720                                         break;
 721                                 default:
 722                                         $tags[$tag] = $val;
 723                                         break;
 724                                 }
 725                                 break;
 726
 727                         case 'SubjectDistance':
 728                                 $tags[$tag] = $this->msg( $tag, '', $this->formatNum( $val ) );
 729                                 break;
 730
 731                         case 'MeteringMode':
 732                                 switch( $val ) {
 733                                 case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 255:
 734                                         $tags[$tag] = $this->msg( $tag, $val );
 735                                         break;
 736                                 default:
 737                                         $tags[$tag] = $val;
 738                                         break;
 739                                 }
 740                                 break;
 741
 742                         case 'LightSource':
 743                                 switch( $val ) {
 744                                 case 0: case 1: case 2: case 3: case 4: case 9: case 10: case 11:
 745                                 case 12: case 13: case 14: case 15: case 17: case 18: case 19: case 20:
 746                                 case 21: case 22: case 23: case 24: case 255:
 747                                         $tags[$tag] = $this->msg( $tag, $val );
 748                                         break;
 749                                 default:
 750                                         $tags[$tag] = $val;
 751                                         break;
 752                                 }
 753                                 break;
 754
 755                         // TODO: Flash
 756                         case 'FocalPlaneResolutionUnit':
 757                                 switch( $val ) {
 758                                 case 2:
 759                                         $tags[$tag] = $this->msg( $tag, $val );
 760                                         break;
 761                                 default:
 762                                         $tags[$tag] = $val;
 763                                         break;
 764                                 }
 765                                 break;
 766
 767                         case 'SensingMethod':
 768                                 switch( $val ) {
 769                                 case 1: case 2: case 3: case 4: case 5: case 7: case 8:
 770                                         $tags[$tag] = $this->msg( $tag, $val );
 771                                         break;
 772                                 default:
 773                                         $tags[$tag] = $val;
 774                                         break;
 775                                 }
 776                                 break;
 777
 778                         case 'FileSource':
 779                                 switch( $val ) {
 780                                 case 3:
 781                                         $tags[$tag] = $this->msg( $tag, $val );
 782                                         break;
 783                                 default:
 784                                         $tags[$tag] = $val;
 785                                         break;
 786                                 }
 787                                 break;
 788
 789                         case 'SceneType':
 790                                 switch( $val ) {
 791                                 case 1:
 792                                         $tags[$tag] = $this->msg( $tag, $val );
 793                                         break;
 794                                 default:
 795                                         $tags[$tag] = $val;
 796                                         break;
 797                                 }
 798                                 break;
 799
 800                         case 'CustomRendered':
 801                                 switch( $val ) {
 802                                 case 0: case 1:
 803                                         $tags[$tag] = $this->msg( $tag, $val );
 804                                         break;
 805                                 default:
 806                                         $tags[$tag] = $val;
 807                                         break;
 808                                 }
 809                                 break;
 810
 811                         case 'ExposureMode':
 812                                 switch( $val ) {
 813                                 case 0: case 1: case 2:
 814                                         $tags[$tag] = $this->msg( $tag, $val );
 815                                         break;
 816                                 default:
 817                                         $tags[$tag] = $val;
 818                                         break;
 819                                 }
 820                                 break;
 821
 822                         case 'WhiteBalance':
 823                                 switch( $val ) {
 824                                 case 0: case 1:
 825                                         $tags[$tag] = $this->msg( $tag, $val );
 826                                         break;
 827                                 default:
 828                                         $tags[$tag] = $val;
 829                                         break;
 830                                 }
 831                                 break;
 832
 833                         case 'SceneCaptureType':
 834                                 switch( $val ) {
 835                                 case 0: case 1: case 2: case 3:
 836                                         $tags[$tag] = $this->msg( $tag, $val );
 837                                         break;
 838                                 default:
 839                                         $tags[$tag] = $val;
 840                                         break;
 841                                 }
 842                                 break;
 843
 844                         case 'GainControl':
 845                                 switch( $val ) {
 846                                 case 0: case 1: case 2: case 3: case 4:
 847                                         $tags[$tag] = $this->msg( $tag, $val );
 848                                         break;
 849                                 default:
 850                                         $tags[$tag] = $val;
 851                                         break;
 852                                 }
 853                                 break;
 854
 855                         case 'Contrast':
 856                                 switch( $val ) {
 857                                 case 0: case 1: case 2:
 858                                         $tags[$tag] = $this->msg( $tag, $val );
 859                                         break;
 860                                 default:
 861                                         $tags[$tag] = $val;
 862                                         break;
 863                                 }
 864                                 break;
 865
 866                         case 'Saturation':
 867                                 switch( $val ) {
 868                                 case 0: case 1: case 2:
 869                                         $tags[$tag] = $this->msg( $tag, $val );
 870                                         break;
 871                                 default:
 872                                         $tags[$tag] = $val;
 873                                         break;
 874                                 }
 875                                 break;
 876
 877                         case 'Sharpness':
 878                                 switch( $val ) {
 879                                 case 0: case 1: case 2:
 880                                         $tags[$tag] = $this->msg( $tag, $val );
 881                                         break;
 882                                 default:
 883                                         $tags[$tag] = $val;
 884                                         break;
 885                                 }
 886                                 break;
 887
 888                         case 'SubjectDistanceRange':
 889                                 switch( $val ) {
 890                                 case 0: case 1: case 2: case 3:
 891                                         $tags[$tag] = $this->msg( $tag, $val );
 892                                         break;
 893                                 default:
 894                                         $tags[$tag] = $val;
 895                                         break;
 896                                 }
 897                                 break;
 898
 899                         case 'GPSLatitudeRef':
 900                         case 'GPSDestLatitudeRef':
 901                                 switch( $val ) {
 902                                 case 'N': case 'S':
 903                                         $tags[$tag] = $this->msg( 'GPSLatitude', $val );
 904                                         break;
 905                                 default:
 906                                         $tags[$tag] = $val;
 907                                         break;
 908                                 }
 909                                 break;
 910
 911                         case 'GPSLongitudeRef':
 912                         case 'GPSDestLongitudeRef':
 913                                 switch( $val ) {
 914                                 case 'E': case 'W':
 915                                         $tags[$tag] = $this->msg( 'GPSLongitude', $val );
 916                                         break;
 917                                 default:
 918                                         $tags[$tag] = $val;
 919                                         break;
 920                                 }
 921                                 break;
 922
 923                         case 'GPSStatus':
 924                                 switch( $val ) {
 925                                 case 'A': case 'V':
 926                                         $tags[$tag] = $this->msg( $tag, $val );
 927                                         break;
 928                                 default:
 929                                         $tags[$tag] = $val;
 930                                         break;
 931                                 }
 932                                 break;
 933
 934                         case 'GPSMeasureMode':
 935                                 switch( $val ) {
 936                                 case 2: case 3:
 937                                         $tags[$tag] = $this->msg( $tag, $val );
 938                                         break;
 939                                 default:
 940                                         $tags[$tag] = $val;
 941                                         break;
 942                                 }
 943                                 break;
 944
 945                         case 'GPSSpeedRef':
 946                         case 'GPSDestDistanceRef':
 947                                 switch( $val ) {
 948                                 case 'K': case 'M': case 'N':
 949                                         $tags[$tag] = $this->msg( 'GPSSpeed', $val );
 950                                         break;
 951                                 default:
 952                                         $tags[$tag] = $val;
 953                                         break;
 954                                 }
 955                                 break;
 956
 957                         case 'GPSTrackRef':
 958                         case 'GPSImgDirectionRef':
 959                         case 'GPSDestBearingRef':
 960                                 switch( $val ) {
 961                                 case 'T': case 'M':
 962                                         $tags[$tag] = $this->msg( 'GPSDirection', $val );
 963                                         break;
 964                                 default:
 965                                         $tags[$tag] = $val;
 966                                         break;
 967                                 }
 968                                 break;
 969
 970                         case 'GPSDateStamp':
 971                                 $tags[$tag] = $wgLang->date( substr( $val, 0, 4 ) . substr( $val, 5, 2 ) . substr( $val, 8, 2 ) . '000000' );
 972                                 break;
 973
 974                         // This is not in the Exif standard, just a special
 975                         // case for our purposes which enables wikis to wikify
 976                         // the make, model and software name to link to their articles.
 977                         case 'Make':
 978                         case 'Model':
 979                         case 'Software':
 980                                 $tags[$tag] = $this->msg( $tag, '', $val );
 981                                 break;
 982                         default:
 983                                 $tags[$tag] = $this->formatNum( $val );
 984                                 break;
 985                         }
 986                 }
 987
 988                 return $tags;
 989         }
 990
 991         /**
 992          * Conviniance function for getFormattedData()
 993          *
 994          * @access private
 995          *
 996          * @param string $tag The tag name to pass on
 997          * @param string $val The value of the tag
 998          * @param string $arg An argument to pass ($1)
 999          * @return string A wfMsg of "exif-$tag-$val" in lower case
1000          */
1001         function msg( $tag, $val, $arg = null ) {
1002                 if ($val === '')
1003                         $val = 'value';
1004                 return wfMsg( strtolower( "exif-$tag-$val" ), $arg );
1005         }
1006
1007         /**
1008          * Format a number, convert numbers from fractions into floating point
1009          * numbers
1010          *
1011          * @access private
1012          *
1013          * @param mixed $num The value to format
1014          * @return mixed A floating point number or whatever we were fed
1015          */
1016         function formatNum( $num ) {
1017                 if ( preg_match( '/^(\d+)\/(\d+)$/', $num, $m ) )
1018                         return $m[2] != 0 ? $m[1] / $m[2] : $num;
1019                 else
1020                         return $num;
1021         }
1022 }