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                 $this->mRawExifData = exif_read_data( $file );
 291                 wfRestoreWarnings();
 292
 293                 $this->makeFilteredData();
 294                 $this->makeFormattedData();
 295
 296                 $this->debugFile( $basename, __FUNCTION__, false );
 297         }
 298
 299         /**#@+
 300          * @access private
 301          */
 302         /**
 303          * Generate a flat list of the exif tags
 304          */
 305         function makeFlatExifTags() {
 306                 $this->extractTags( $this->mExifTags );
 307         }
 308
 309         /**
 310          * A recursing extractor function used by makeFlatExifTags()
 311          *
 312          * Note: This used to use an array_walk function, but it made PHP5
 313          * segfault, see `cvs diff -u -r 1.4 -r 1.5 Exif.php`
 314          */
 315         function extractTags( &$tagset ) {
 316                 foreach( $tagset as $key => $val ) {
 317                         if( is_array( $val ) ) {
 318                                 $this->extractTags( $val );
 319                         } else {
 320                                 $this->mFlatExifTags[$key] = $val;
 321                         }
 322                 }
 323         }
 324
 325         /**
 326          * Make $this->mFilteredExifData
 327          */
 328         function makeFilteredData() {
 329                 $this->mFilteredExifData = $this->mRawExifData;
 330
 331                 foreach( $this->mFilteredExifData as $k => $v ) {
 332                         if ( !in_array( $k, array_keys( $this->mFlatExifTags ) ) ) {
 333                                 $this->debug( $v, __FUNCTION__, "'$k' is not a valid Exif tag" );
 334                                 unset( $this->mFilteredExifData[$k] );
 335                         }
 336                 }
 337
 338                 foreach( $this->mFilteredExifData as $k => $v ) {
 339                         if ( !$this->validate($k, $v) ) {
 340                                 $this->debug( $v, __FUNCTION__, "'$k' contained invalid data" );
 341                                 unset( $this->mFilteredExifData[$k] );
 342                         }
 343                 }
 344         }
 345
 346         function makeFormattedData( $data = null ) {
 347                 $format = new FormatExif( $this->getFilteredData() );
 348                 $this->mFormattedExifData = $format->getFormattedData();
 349         }
 350         /**#@-*/
 351
 352         /**#@+
 353          * @return array
 354          */
 355         /**
 356          * Get $this->mRawExifData
 357          */
 358         function getData() {
 359                 return $this->mRawExifData;
 360         }
 361
 362         /**
 363          * Get $this->mFilteredExifData
 364          */
 365         function getFilteredData() {
 366                 return $this->mFilteredExifData;
 367         }
 368
 369         /**
 370          * Get $this->mFormattedExifData
 371          */
 372         function getFormattedData() {
 373                 return $this->mFormattedExifData;
 374         }
 375         /**#@-*/
 376
 377         /**
 378          * The version of the output format
 379          *
 380          * Before the actual metadata information is saved in the database we
 381          * strip some of it since we don't want to save things like thumbnails
 382          * which usually accompany Exif data. This value gets saved in the
 383          * database along with the actual Exif data, and if the version in the
 384          * database doesn't equal the value returned by this function the Exif
 385          * data is regenerated.
 386          *
 387          * @return int
 388          */
 389         function version() {
 390                 return 1; // We don't need no bloddy constants!
 391         }
 392
 393         /**#@+
 394          * Validates if a tag value is of the type it should be according to the Exif spec
 395          *
 396          * @access private
 397          *
 398          * @param mixed $in The input value to check
 399          * @return bool
 400          */
 401         function isByte( $in ) {
 402                 if ( sprintf('%d', $in) == $in && $in >= 0 && $in <= 255 ) {
 403                         $this->debug( $in, __FUNCTION__, true );
 404                         return true;
 405                 } else {
 406                         $this->debug( $in, __FUNCTION__, false );
 407                         return false;
 408                 }
 409         }
 410
 411         function isASCII( $in ) {
 412                 if ( preg_match( "/[^\x0a\x20-\x7e]/", $in ) ) {
 413                         $this->debug( $in, __FUNCTION__, 'found a character not in our whitelist' );
 414                         return false;
 415                 }
 416
 417                 if ( preg_match( "/^\s*$/", $in ) ) {
 418                         $this->debug( $in, __FUNCTION__, 'input consisted solely of whitespace' );
 419                         return false;
 420                 }
 421
 422                 return true;
 423         }
 424
 425         function isShort( $in ) {
 426                 if ( sprintf('%d', $in) == $in && $in >= 0 && $in <= 65536 ) {
 427                         $this->debug( $in, __FUNCTION__, true );
 428                         return true;
 429                 } else {
 430                         $this->debug( $in, __FUNCTION__, false );
 431                         return false;
 432                 }
 433         }
 434
 435         function isLong( $in ) {
 436                 if ( sprintf('%d', $in) == $in && $in >= 0 && $in <= 4294967296 ) {
 437                         $this->debug( $in, __FUNCTION__, true );
 438                         return true;
 439                 } else {
 440                         $this->debug( $in, __FUNCTION__, false );
 441                         return false;
 442                 }
 443         }
 444
 445         function isRational( $in ) {
 446                 if ( @preg_match( "/^(\d+)\/(\d+[1-9]|[1-9]\d*)$/", $in, $m ) ) { # Avoid division by zero
 447                         return $this->isLong( $m[1] ) && $this->isLong( $m[2] );
 448                 } else {
 449                         $this->debug( $in, __FUNCTION__, 'fed a non-fraction value' );
 450                         return false;
 451                 }
 452         }
 453
 454         function isUndefined( $in ) {
 455                 if ( preg_match( "/^\d{4}$/", $in ) ) { // Allow ExifVersion and FlashpixVersion
 456                         $this->debug( $in, __FUNCTION__, true );
 457                         return true;
 458                 } else {
 459                         $this->debug( $in, __FUNCTION__, false );
 460                         return false;
 461                 }
 462         }
 463
 464         function isSlong( $in ) {
 465                 if ( $this->isLong( abs( $in ) ) ) {
 466                         $this->debug( $in, __FUNCTION__, true );
 467                         return true;
 468                 } else {
 469                         $this->debug( $in, __FUNCTION__, false );
 470                         return false;
 471                 }
 472         }
 473
 474         function isSrational( $in ) {
 475                 if ( preg_match( "/^(\d+)\/(\d+[1-9]|[1-9]\d*)$/", $in, $m ) ) { # Avoid division by zero
 476                         return $this->isSlong( $m[0] ) && $this->isSlong( $m[1] );
 477                 } else {
 478                         $this->debug( $in, __FUNCTION__, 'fed a non-fraction value' );
 479                         return false;
 480                 }
 481         }
 482         /**#@-*/
 483
 484         /**
 485          * Validates if a tag has a legal value according to the Exif spec
 486          *
 487          * @access private
 488          *
 489          * @param string $tag The tag to check
 490          * @param mixed  $val The value of the tag
 491          * @return bool
 492          */
 493         function validate( $tag, $val ) {
 494                 $debug = "tag is '$tag'";
 495                 // Fucks up if not typecast
 496                 switch( (string)$this->mFlatExifTags[$tag] ) {
 497                         case (string)MW_EXIF_BYTE:
 498                                 $this->debug( $val, __FUNCTION__, $debug );
 499                                 return $this->isByte( $val );
 500                         case (string)MW_EXIF_ASCII:
 501                                 $this->debug( $val, __FUNCTION__, $debug );
 502                                 return $this->isASCII( $val );
 503                         case (string)MW_EXIF_SHORT:
 504                                 $this->debug( $val, __FUNCTION__, $debug );
 505                                 return $this->isShort( $val );
 506                         case (string)MW_EXIF_LONG:
 507                                 $this->debug( $val, __FUNCTION__, $debug );
 508                                 return $this->isLong( $val );
 509                         case (string)MW_EXIF_RATIONAL:
 510                                 $this->debug( $val, __FUNCTION__, $debug );
 511                                 return $this->isRational( $val );
 512                         case (string)MW_EXIF_UNDEFINED:
 513                                 $this->debug( $val, __FUNCTION__, $debug );
 514                                 return $this->isUndefined( $val );
 515                         case (string)MW_EXIF_SLONG:
 516                                 $this->debug( $val, __FUNCTION__, $debug );
 517                                 return $this->isSlong( $val );
 518                         case (string)MW_EXIF_SRATIONAL:
 519                                 $this->debug( $val, __FUNCTION__, $debug );
 520                                 return $this->isSrational( $val );
 521                         case (string)MW_EXIF_SHORT.','.MW_EXIF_LONG:
 522                                 $this->debug( $val, __FUNCTION__, $debug );
 523                                 return $this->isShort( $val ) || $this->isLong( $val );
 524                         default:
 525                                 $this->debug( $val, __FUNCTION__, "The tag '$tag' is unknown" );
 526                                 return false;
 527                 }
 528         }
 529
 530         /**
 531          * Conviniance function for debugging output
 532          *
 533          * @access private
 534          *
 535          * @param mixed $in
 536          * @param string $fname
 537          * @param mixed $action
 538          */
 539          function debug( $in, $fname, $action = null ) {
 540                 $type = gettype( $in );
 541                 $class = ucfirst( __CLASS__ );
 542                 if ( $type === 'array' )
 543                         $in = print_r( $in, true );
 544
 545                 if ( $action === true )
 546                         wfDebugLog( $this->log, "$class::$fname: accepted: '$in' (type: $type)\n");
 547                 elseif ( $action === false )
 548                         wfDebugLog( $this->log, "$class::$fname: rejected: '$in' (type: $type)\n");
 549                 elseif ( $action === null )
 550                         wfDebugLog( $this->log, "$class::$fname: input was: '$in' (type: $type)\n");
 551                 else
 552                         wfDebugLog( $this->log, "$class::$fname: $action (type: $type; content: '$in')\n");
 553         }
 554
 555         /**
 556          * Conviniance function for debugging output
 557          *
 558          * @access private
 559          *
 560          * @param string $basename The name of the file being processed
 561          * @paran string $fname The name of the function calling this function
 562          * @param bool $bool $io Specify whether we're beginning or ending
 563          */
 564         function debugFile( $basename, $fname, $io ) {
 565                 $class = ucfirst( __CLASS__ );
 566                 if ( $io )
 567                         wfDebugLog( $this->log, "$class::$fname: begin processing: '$basename'\n" );
 568                 else
 569                         wfDebugLog( $this->log, "$class::$fname: end processing: '$basename'\n" );
 570         }
 571
 572 }
 573
 574 /**
 575  * @package MediaWiki
 576  * @subpackage Metadata
 577  */
 578 class FormatExif {
 579         /**
 580          * The Exif data to format
 581          *
 582          * @var array
 583          * @access private
 584          */
 585         var $mExif;
 586
 587         /**
 588          * Constructor
 589          *
 590          * @param array $exif The Exif data to format ( as returned by
 591          *                    Exif::getFilteredData() )
 592          */
 593         function FormatExif( $exif ) {
 594                 $this->mExif = $exif;
 595         }
 596
 597         /**
 598          * Numbers given by Exif user agents are often magical, that is they
 599          * should be replaced by a detailed explanation depending on their
 600          * value which most of the time are plain integers. This function
 601          * formats Exif values into human readable form.
 602          *
 603          * @return array
 604          */
 605         function getFormattedData() {
 606                 global $wgLang;
 607
 608                 $tags =& $this->mExif;
 609
 610                 $resolutionunit = !isset( $tags['ResolutionUnit'] ) || $tags['ResolutionUnit'] == 2 ? 2 : 3;
 611                 unset( $tags['ResolutionUnit'] );
 612
 613                 foreach( $tags as $tag => $val ) {
 614                         switch( $tag ) {
 615                         case 'Compression':
 616                                 switch( $val ) {
 617                                 case 1: case 6:
 618                                         $tags[$tag] = $this->msg( $tag, $val );
 619                                         break;
 620                                 default:
 621                                         $tags[$tag] = $val;
 622                                         break;
 623                                 }
 624                                 break;
 625
 626                         case 'PhotometricInterpretation':
 627                                 switch( $val ) {
 628                                 case 2: case 6:
 629                                         $tags[$tag] = $this->msg( $tag, $val );
 630                                         break;
 631                                 default:
 632                                         $tags[$tag] = $val;
 633                                         break;
 634                                 }
 635                                 break;
 636
 637                         case 'Orientation':
 638                                 switch( $val ) {
 639                                 case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 8:
 640                                         $tags[$tag] = $this->msg( $tag, $val );
 641                                         break;
 642                                 default:
 643                                         $tags[$tag] = $val;
 644                                         break;
 645                                 }
 646                                 break;
 647
 648                         case 'PlanarConfiguration':
 649                                 switch( $val ) {
 650                                 case 1: case 2:
 651                                         $tags[$tag] = $this->msg( $tag, $val );
 652                                         break;
 653                                 default:
 654                                         $tags[$tag] = $val;
 655                                         break;
 656                                 }
 657                                 break;
 658
 659                         // TODO: YCbCrSubSampling
 660                         // TODO: YCbCrPositioning
 661
 662                         case 'XResolution':
 663                         case 'YResolution':
 664                                 switch( $resolutionunit ) {
 665                                         case 2:
 666                                                 $tags[$tag] = $this->msg( 'XYResolution', 'i', $this->formatNum( $val ) );
 667                                                 break;
 668                                         case 3:
 669                                                 $this->msg( 'XYResolution', 'c', $this->formatNum( $val ) );
 670                                                 break;
 671                                         default:
 672                                                 $tags[$tag] = $val;
 673                                                 break;
 674                                 }
 675                                 break;
 676
 677                         // TODO: YCbCrCoefficients  #p27 (see annex E)
 678                         case 'ExifVersion': case 'FlashpixVersion':
 679                                 $tags[$tag] = "$val"/100;
 680                                 break;
 681
 682                         case 'ColorSpace':
 683                                 switch( $val ) {
 684                                 case 1: case 'FFFF.H':
 685                                         $tags[$tag] = $this->msg( $tag, $val );
 686                                         break;
 687                                 default:
 688                                         $tags[$tag] = $val;
 689                                         break;
 690                                 }
 691                                 break;
 692
 693                         case 'ComponentsConfiguration':
 694                                 switch( $val ) {
 695                                 case 0: case 1: case 2: case 3: case 4: case 5: case 6:
 696                                         $tags[$tag] = $this->msg( $tag, $val );
 697                                         break;
 698                                 default:
 699                                         $tags[$tag] = $val;
 700                                         break;
 701                                 }
 702                                 break;
 703
 704                         case 'DateTime':
 705                         case 'DateTimeOriginal':
 706                         case 'DateTimeDigitized':
 707                                 $tags[$tag] = $wgLang->timeanddate( wfTimestamp(TS_MW, $val) );
 708                                 break;
 709
 710                         case 'ExposureProgram':
 711                                 switch( $val ) {
 712                                 case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 8:
 713                                         $tags[$tag] = $this->msg( $tag, $val );
 714                                         break;
 715                                 default:
 716                                         $tags[$tag] = $val;
 717                                         break;
 718                                 }
 719                                 break;
 720
 721                         case 'SubjectDistance':
 722                                 $tags[$tag] = $this->msg( $tag, '', $this->formatNum( $val ) );
 723                                 break;
 724
 725                         case 'MeteringMode':
 726                                 switch( $val ) {
 727                                 case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 255:
 728                                         $tags[$tag] = $this->msg( $tag, $val );
 729                                         break;
 730                                 default:
 731                                         $tags[$tag] = $val;
 732                                         break;
 733                                 }
 734                                 break;
 735
 736                         case 'LightSource':
 737                                 switch( $val ) {
 738                                 case 0: case 1: case 2: case 3: case 4: case 9: case 10: case 11:
 739                                 case 12: case 13: case 14: case 15: case 17: case 18: case 19: case 20:
 740                                 case 21: case 22: case 23: case 24: case 255:
 741                                         $tags[$tag] = $this->msg( $tag, $val );
 742                                         break;
 743                                 default:
 744                                         $tags[$tag] = $val;
 745                                         break;
 746                                 }
 747                                 break;
 748
 749                         // TODO: Flash
 750                         case 'FocalPlaneResolutionUnit':
 751                                 switch( $val ) {
 752                                 case 2:
 753                                         $tags[$tag] = $this->msg( $tag, $val );
 754                                         break;
 755                                 default:
 756                                         $tags[$tag] = $val;
 757                                         break;
 758                                 }
 759                                 break;
 760
 761                         case 'SensingMethod':
 762                                 switch( $val ) {
 763                                 case 1: case 2: case 3: case 4: case 5: case 7: case 8:
 764                                         $tags[$tag] = $this->msg( $tag, $val );
 765                                         break;
 766                                 default:
 767                                         $tags[$tag] = $val;
 768                                         break;
 769                                 }
 770                                 break;
 771
 772                         case 'FileSource':
 773                                 switch( $val ) {
 774                                 case 3:
 775                                         $tags[$tag] = $this->msg( $tag, $val );
 776                                         break;
 777                                 default:
 778                                         $tags[$tag] = $val;
 779                                         break;
 780                                 }
 781                                 break;
 782
 783                         case 'SceneType':
 784                                 switch( $val ) {
 785                                 case 1:
 786                                         $tags[$tag] = $this->msg( $tag, $val );
 787                                         break;
 788                                 default:
 789                                         $tags[$tag] = $val;
 790                                         break;
 791                                 }
 792                                 break;
 793
 794                         case 'CustomRendered':
 795                                 switch( $val ) {
 796                                 case 0: case 1:
 797                                         $tags[$tag] = $this->msg( $tag, $val );
 798                                         break;
 799                                 default:
 800                                         $tags[$tag] = $val;
 801                                         break;
 802                                 }
 803                                 break;
 804
 805                         case 'ExposureMode':
 806                                 switch( $val ) {
 807                                 case 0: case 1: case 2:
 808                                         $tags[$tag] = $this->msg( $tag, $val );
 809                                         break;
 810                                 default:
 811                                         $tags[$tag] = $val;
 812                                         break;
 813                                 }
 814                                 break;
 815
 816                         case 'WhiteBalance':
 817                                 switch( $val ) {
 818                                 case 0: case 1:
 819                                         $tags[$tag] = $this->msg( $tag, $val );
 820                                         break;
 821                                 default:
 822                                         $tags[$tag] = $val;
 823                                         break;
 824                                 }
 825                                 break;
 826
 827                         case 'SceneCaptureType':
 828                                 switch( $val ) {
 829                                 case 0: case 1: case 2: case 3:
 830                                         $tags[$tag] = $this->msg( $tag, $val );
 831                                         break;
 832                                 default:
 833                                         $tags[$tag] = $val;
 834                                         break;
 835                                 }
 836                                 break;
 837
 838                         case 'GainControl':
 839                                 switch( $val ) {
 840                                 case 0: case 1: case 2: case 3: case 4:
 841                                         $tags[$tag] = $this->msg( $tag, $val );
 842                                         break;
 843                                 default:
 844                                         $tags[$tag] = $val;
 845                                         break;
 846                                 }
 847                                 break;
 848
 849                         case 'Contrast':
 850                                 switch( $val ) {
 851                                 case 0: case 1: case 2:
 852                                         $tags[$tag] = $this->msg( $tag, $val );
 853                                         break;
 854                                 default:
 855                                         $tags[$tag] = $val;
 856                                         break;
 857                                 }
 858                                 break;
 859
 860                         case 'Saturation':
 861                                 switch( $val ) {
 862                                 case 0: case 1: case 2:
 863                                         $tags[$tag] = $this->msg( $tag, $val );
 864                                         break;
 865                                 default:
 866                                         $tags[$tag] = $val;
 867                                         break;
 868                                 }
 869                                 break;
 870
 871                         case 'Sharpness':
 872                                 switch( $val ) {
 873                                 case 0: case 1: case 2:
 874                                         $tags[$tag] = $this->msg( $tag, $val );
 875                                         break;
 876                                 default:
 877                                         $tags[$tag] = $val;
 878                                         break;
 879                                 }
 880                                 break;
 881
 882                         case 'SubjectDistanceRange':
 883                                 switch( $val ) {
 884                                 case 0: case 1: case 2: case 3:
 885                                         $tags[$tag] = $this->msg( $tag, $val );
 886                                         break;
 887                                 default:
 888                                         $tags[$tag] = $val;
 889                                         break;
 890                                 }
 891                                 break;
 892
 893                         case 'GPSLatitudeRef':
 894                         case 'GPSDestLatitudeRef':
 895                                 switch( $val ) {
 896                                 case 'N': case 'S':
 897                                         $tags[$tag] = $this->msg( 'GPSLatitude', $val );
 898                                         break;
 899                                 default:
 900                                         $tags[$tag] = $val;
 901                                         break;
 902                                 }
 903                                 break;
 904
 905                         case 'GPSLongitudeRef':
 906                         case 'GPSDestLongitudeRef':
 907                                 switch( $val ) {
 908                                 case 'E': case 'W':
 909                                         $tags[$tag] = $this->msg( 'GPSLongitude', $val );
 910                                         break;
 911                                 default:
 912                                         $tags[$tag] = $val;
 913                                         break;
 914                                 }
 915                                 break;
 916
 917                         case 'GPSStatus':
 918                                 switch( $val ) {
 919                                 case 'A': case 'V':
 920                                         $tags[$tag] = $this->msg( $tag, $val );
 921                                         break;
 922                                 default:
 923                                         $tags[$tag] = $val;
 924                                         break;
 925                                 }
 926                                 break;
 927
 928                         case 'GPSMeasureMode':
 929                                 switch( $val ) {
 930                                 case 2: case 3:
 931                                         $tags[$tag] = $this->msg( $tag, $val );
 932                                         break;
 933                                 default:
 934                                         $tags[$tag] = $val;
 935                                         break;
 936                                 }
 937                                 break;
 938
 939                         case 'GPSSpeedRef':
 940                         case 'GPSDestDistanceRef':
 941                                 switch( $val ) {
 942                                 case 'K': case 'M': case 'N':
 943                                         $tags[$tag] = $this->msg( 'GPSSpeed', $val );
 944                                         break;
 945                                 default:
 946                                         $tags[$tag] = $val;
 947                                         break;
 948                                 }
 949                                 break;
 950
 951                         case 'GPSTrackRef':
 952                         case 'GPSImgDirectionRef':
 953                         case 'GPSDestBearingRef':
 954                                 switch( $val ) {
 955                                 case 'T': case 'M':
 956                                         $tags[$tag] = $this->msg( 'GPSDirection', $val );
 957                                         break;
 958                                 default:
 959                                         $tags[$tag] = $val;
 960                                         break;
 961                                 }
 962                                 break;
 963
 964                         case 'GPSDateStamp':
 965                                 $tags[$tag] = $wgLang->date( substr( $val, 0, 4 ) . substr( $val, 5, 2 ) . substr( $val, 8, 2 ) . '000000' );
 966                                 break;
 967
 968                         // This is not in the Exif standard, just a special
 969                         // case for our purposes which enables wikis to wikify
 970                         // the make, model and software name to link to their articles.
 971                         case 'Make':
 972                         case 'Model':
 973                         case 'Software':
 974                                 $tags[$tag] = $this->msg( $tag, '', $val );
 975                                 break;
 976                         default:
 977                                 $tags[$tag] = $this->formatNum( $val );
 978                                 break;
 979                         }
 980                 }
 981
 982                 return $tags;
 983         }
 984
 985         /**
 986          * Conviniance function for getFormattedData()
 987          *
 988          * @access private
 989          *
 990          * @param string $tag The tag name to pass on
 991          * @param string $val The value of the tag
 992          * @param string $arg An argument to pass ($1)
 993          * @return string A wfMsg of "exif-$tag-$val" in lower case
 994          */
 995         function msg( $tag, $val, $arg = null ) {
 996                 if ($val === '')
 997                         $val = 'value';
 998                 return wfMsg( strtolower( "exif-$tag-$val" ), $arg );
 999         }
1000
1001         /**
1002          * Format a number, convert numbers from fractions into floating point
1003          * numbers
1004          *
1005          * @access private
1006          *
1007          * @param mixed $num The value to format
1008          * @return mixed A floating point number or whatever we were fed
1009          */
1010         function formatNum( $num ) {
1011                 if ( preg_match( '/^(\d+)\/(\d+)$/', $num, $m ) )
1012                         return $m[2] != 0 ? $m[1] / $m[2] : $num;
1013                 else
1014                         return $num;
1015         }
1016 }