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 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          * Constructor
  87          */
  88         function Exif( $file ) {
  89                 /**
  90                  * Page numbers here refer to pages in the EXIF 2.2 standard
  91                  *
  92                  * @link http://exif.org/Exif2-2.PDF The Exif 2.2 specification
  93                  */
  94                 $this->mExifTags = array(
  95                         # TIFF Rev. 6.0 Attribute Information (p22)
  96                         'tiff' => array(
  97                                 # Tags relating to image structure
  98                                 'structure' => array(
  99                                         'ImageWidth' => MW_EXIF_SHORT.','.MW_EXIF_LONG,         # Image width
 100                                         'ImageLength' => MW_EXIF_SHORT.','.MW_EXIF_LONG,        # Image height
 101                                         'BitsPerSample' => MW_EXIF_SHORT,                       # Number of bits per component
 102                                         # "When a primary image is JPEG compressed, this designation is not"
 103                                         # "necessary and is omitted." (p23)
 104                                         'Compression' => MW_EXIF_SHORT,                         # Compression scheme #p23
 105                                         'PhotometricInterpretation' => MW_EXIF_SHORT,           # Pixel composition #p23
 106                                         'Orientation' => MW_EXIF_SHORT,                         # Orientation of image #p24
 107                                         'SamplesPerPixel' => MW_EXIF_SHORT,                     # Number of components
 108                                         'PlanarConfiguration' => MW_EXIF_SHORT,                 # Image data arrangement #p24
 109                                         'YCbCrSubSampling' => MW_EXIF_SHORT,                    # Subsampling ratio of Y to C #p24
 110                                         'YCbCrPositioning' => MW_EXIF_SHORT,                    # Y and C positioning #p24-25
 111                                         'XResolution' => MW_EXIF_RATIONAL,                      # Image resolution in width direction
 112                                         'YResolution' => MW_EXIF_RATIONAL,                      # Image resolution in height direction
 113                                         'ResolutionUnit' => MW_EXIF_SHORT,                      # Unit of X and Y resolution #(p26)
 114                                 ),
 115
 116                                 # Tags relating to recording offset
 117                                 'offset' => array(
 118                                         'StripOffsets' => MW_EXIF_SHORT.','.MW_EXIF_LONG,                       # Image data location
 119                                         'RowsPerStrip' => MW_EXIF_SHORT.','.MW_EXIF_LONG,                       # Number of rows per strip
 120                                         'StripByteCounts' => MW_EXIF_SHORT.','.MW_EXIF_LONG,                    # Bytes per compressed strip
 121                                         'JPEGInterchangeFormat' => MW_EXIF_SHORT.','.MW_EXIF_LONG,              # Offset to JPEG SOI
 122                                         'JPEGInterchangeFormatLength' => MW_EXIF_SHORT.','.MW_EXIF_LONG,        # Bytes of JPEG data
 123                                 ),
 124
 125                                 # Tags relating to image data characteristics
 126                                 'characteristics' => array(
 127                                         'TransferFunction' => MW_EXIF_SHORT,            # Transfer function
 128                                         'WhitePoint' => MW_EXIF_RATIONAL,               # White point chromaticity
 129                                         'PrimaryChromaticities' => MW_EXIF_RATIONAL,    # Chromaticities of primarities
 130                                         'YCbCrCoefficients' => MW_EXIF_RATIONAL,        # Color space transformation matrix coefficients #p27
 131                                         'ReferenceBlackWhite' => MW_EXIF_RATIONAL       # Pair of black and white reference values
 132                                 ),
 133
 134                                 # Other tags
 135                                 'other' => array(
 136                                         'DateTime' => MW_EXIF_ASCII,            # File change date and time
 137                                         'ImageDescription' => MW_EXIF_ASCII,    # Image title
 138                                         'Make' => MW_EXIF_ASCII,                # Image input equipment manufacturer
 139                                         'Model' => MW_EXIF_ASCII,               # Image input equipment model
 140                                         'Software' => MW_EXIF_ASCII,            # Software used
 141                                         'Artist' => MW_EXIF_ASCII,              # Person who created the image
 142                                         'Copyright' => MW_EXIF_ASCII,           # Copyright holder
 143                                 ),
 144                         ),
 145
 146                         # Exif IFD Attribute Information (p30-31)
 147                         'exif' => array(
 148                                 # Tags relating to version
 149                                 'version' => array(
 150                                         # TODO: NOTE: Nonexistence of this field is taken to mean nonconformance
 151                                         # to the EXIF 2.1 AND 2.2 standards
 152                                         'ExifVersion' => MW_EXIF_UNDEFINED,     # Exif version
 153                                         'FlashpixVersion' => MW_EXIF_UNDEFINED, # Supported Flashpix version #p32
 154                                 ),
 155
 156                                 # Tags relating to Image Data Characteristics
 157                                 'characteristics' => array(
 158                                         'ColorSpace' => MW_EXIF_SHORT,          # Color space information #p32
 159                                 ),
 160
 161                                 # Tags relating to image configuration
 162                                 'configuration' => array(
 163                                         'ComponentsConfiguration' => MW_EXIF_UNDEFINED,         # Meaning of each component #p33
 164                                         'CompressedBitsPerPixel' => MW_EXIF_RATIONAL,           # Image compression mode
 165                                         'PixelYDimension' => MW_EXIF_SHORT.','.MW_EXIF_LONG,    # Valid image width
 166                                         'PixelXDimension' => MW_EXIF_SHORT.','.MW_EXIF_LONG,    # Valind image height
 167                                 ),
 168
 169                                 # Tags relating to related user information
 170                                 'user' => array(
 171                                         'MakerNote' => MW_EXIF_UNDEFINED,                       # Manufacturer notes
 172                                         'UserComment' => MW_EXIF_UNDEFINED,                     # User comments #p34
 173                                 ),
 174
 175                                 # Tags relating to related file information
 176                                 'related' => array(
 177                                         'RelatedSoundFile' => MW_EXIF_ASCII,                    # Related audio file
 178                                 ),
 179
 180                                 # Tags relating to date and time
 181                                 'dateandtime' => array(
 182                                         'DateTimeOriginal' => MW_EXIF_ASCII,                    # Date and time of original data generation #p36
 183                                         'DateTimeDigitized' => MW_EXIF_ASCII,                   # Date and time of original data generation
 184                                         'SubSecTime' => MW_EXIF_ASCII,                          # DateTime subseconds
 185                                         'SubSecTimeOriginal' => MW_EXIF_ASCII,                  # DateTimeOriginal subseconds
 186                                         'SubSecTimeDigitized' => MW_EXIF_ASCII,                 # DateTimeDigitized subseconds
 187                                 ),
 188
 189                                 # Tags relating to picture-taking conditions (p31)
 190                                 'conditions' => array(
 191                                         'ExposureTime' => MW_EXIF_RATIONAL,                     # Exposure time
 192                                         'FNumber' => MW_EXIF_RATIONAL,                          # F Number
 193                                         'ExposureProgram' => MW_EXIF_SHORT,                     # Exposure Program #p38
 194                                         'SpectralSensitivity' => MW_EXIF_ASCII,                 # Spectral sensitivity
 195                                         'ISOSpeedRatings' => MW_EXIF_SHORT,                     # ISO speed rating
 196                                         'OECF' => MW_EXIF_UNDEFINED,                            # Optoelectronic conversion factor
 197                                         'ShutterSpeedValue' => MW_EXIF_SRATIONAL,               # Shutter speed
 198                                         'ApertureValue' => MW_EXIF_RATIONAL,                    # Aperture
 199                                         'BrightnessValue' => MW_EXIF_SRATIONAL,                 # Brightness
 200                                         'ExposureBiasValue' => MW_EXIF_SRATIONAL,               # Exposure bias
 201                                         'MaxApertureValue' => MW_EXIF_RATIONAL,                 # Maximum land aperture
 202                                         'SubjectDistance' => MW_EXIF_RATIONAL,                  # Subject distance
 203                                         'MeteringMode' => MW_EXIF_SHORT,                        # Metering mode #p40
 204                                         'LightSource' => MW_EXIF_SHORT,                         # Light source #p40-41
 205                                         'Flash' => MW_EXIF_SHORT,                               # Flash #p41-42
 206                                         'FocalLength' => MW_EXIF_RATIONAL,                      # Lens focal length
 207                                         'SubjectArea' => MW_EXIF_SHORT,                         # Subject area
 208                                         'FlashEnergy' => MW_EXIF_RATIONAL,                      # Flash energy
 209                                         'SpatialFrequencyResponse' => MW_EXIF_UNDEFINED,        # Spatial frequency response
 210                                         'FocalPlaneXResolution' => MW_EXIF_RATIONAL,            # Focal plane X resolution
 211                                         'FocalPlaneYResolution' => MW_EXIF_RATIONAL,            # Focal plane Y resolution
 212                                         'FocalPlaneResolutionUnit' => MW_EXIF_SHORT,            # Focal plane resolution unit #p46
 213                                         'SubjectLocation' => MW_EXIF_SHORT,                     # Subject location
 214                                         'ExposureIndex' => MW_EXIF_RATIONAL,                    # Exposure index
 215                                         'SensingMethod' => MW_EXIF_SHORT,                       # Sensing method #p46
 216                                         'FileSource' => MW_EXIF_UNDEFINED,                      # File source #p47
 217                                         'SceneType' => MW_EXIF_UNDEFINED,                       # Scene type #p47
 218                                         'CFAPattern' => MW_EXIF_UNDEFINED,                      # CFA pattern
 219                                         'CustomRendered' => MW_EXIF_SHORT,                      # Custom image processing #p48
 220                                         'ExposureMode' => MW_EXIF_SHORT,                        # Exposure mode #p48
 221                                         'WhiteBalance' => MW_EXIF_SHORT,                        # White Balance #p49
 222                                         'DigitalZoomRatio' => MW_EXIF_RATIONAL,                 # Digital zoom ration
 223                                         'FocalLengthIn35mmFilm' => MW_EXIF_SHORT,               # Focal length in 35 mm film
 224                                         'SceneCaptureType' => MW_EXIF_SHORT,                    # Scene capture type #p49
 225                                         'GainControl' => MW_EXIF_RATIONAL,                      # Scene control #p49-50
 226                                         'Contrast' => MW_EXIF_SHORT,                            # Contrast #p50
 227                                         'Saturation' => MW_EXIF_SHORT,                          # Saturation #p50
 228                                         'Sharpness' => MW_EXIF_SHORT,                           # Sharpness #p50
 229                                         'DeviceSettingDescription' => MW_EXIF_UNDEFINED,        # Desice settings description
 230                                         'SubjectDistanceRange' => MW_EXIF_SHORT,                # Subject distance range #p51
 231                                 ),
 232
 233                                 'other' => array(
 234                                         'ImageUniqueID' => MW_EXIF_ASCII,       # Unique image ID
 235                                 ),
 236                         ),
 237
 238                         # GPS Attribute Information (p52)
 239                         'gps' => array(
 240                                 'GPSVersionID' => MW_EXIF_BYTE,                 # GPS tag version
 241                                 'GPSLatitudeRef' => MW_EXIF_ASCII,              # North or South Latitude #p52-53
 242                                 'GPSLatitude' => MW_EXIF_RATIONAL,              # Latitude
 243                                 'GPSLongitudeRef' => MW_EXIF_ASCII,             # East or West Longitude #p53
 244                                 'GPSLongitude' => MW_EXIF_RATIONAL,             # Longitude
 245                                 'GPSAltitudeRef' => MW_EXIF_BYTE,               # Altitude reference
 246                                 'GPSAltitude' => MW_EXIF_RATIONAL,              # Altitude
 247                                 'GPSTimeStamp' => MW_EXIF_RATIONAL,             # GPS time (atomic clock)
 248                                 'GPSSatellites' => MW_EXIF_ASCII,               # Satellites used for measurement
 249                                 'GPSStatus' => MW_EXIF_ASCII,                   # Receiver status #p54
 250                                 'GPSMeasureMode' => MW_EXIF_ASCII,              # Measurement mode #p54-55
 251                                 'GPSDOP' => MW_EXIF_RATIONAL,                   # Measurement precision
 252                                 'GPSSpeedRef' => MW_EXIF_ASCII,                 # Speed unit #p55
 253                                 'GPSSpeed' => MW_EXIF_RATIONAL,                 # Speed of GPS receiver
 254                                 'GPSTrackRef' => MW_EXIF_ASCII,                 # Reference for direction of movement #p55
 255                                 'GPSTrack' => MW_EXIF_RATIONAL,                 # Direction of movement
 256                                 'GPSImgDirectionRef' => MW_EXIF_ASCII,          # Reference for direction of image #p56
 257                                 'GPSImgDirection' => MW_EXIF_RATIONAL,          # Direction of image
 258                                 'GPSMapDatum' => MW_EXIF_ASCII,                 # Geodetic survey data used
 259                                 'GPSDestLatitudeRef' => MW_EXIF_ASCII,          # Reference for latitude of destination #p56
 260                                 'GPSDestLatitude' => MW_EXIF_RATIONAL,          # Latitude destination
 261                                 'GPSDestLongitudeRef' => MW_EXIF_ASCII,         # Reference for longitude of destination #p57
 262                                 'GPSDestLongitude' => MW_EXIF_RATIONAL,         # Longitude of destination
 263                                 'GPSDestBearingRef' => MW_EXIF_ASCII,           # Reference for bearing of destination #p57
 264                                 'GPSDestBearing' => MW_EXIF_RATIONAL,           # Bearing of destination
 265                                 'GPSDestDistanceRef' => MW_EXIF_ASCII,          # Reference for distance to destination #p57-58
 266                                 'GPSDestDistance' => MW_EXIF_RATIONAL,          # Distance to destination
 267                                 'GPSProcessingMethod' => MW_EXIF_UNDEFINED,     # Name of GPS processing method
 268                                 'GPSAreaInformation' => MW_EXIF_UNDEFINED,      # Name of GPS area
 269                                 'GPSDateStamp' => MW_EXIF_ASCII,                # GPS date
 270                                 'GPSDifferential' => MW_EXIF_SHORT,             # GPS differential correction
 271                         ),
 272                 );
 273
 274                 $this->makeFlatExifTags();
 275                 wfSuppressWarnings();
 276                 $this->mRawExifData = exif_read_data( $file );
 277                 wfRestoreWarnings();
 278                 $this->makeFilteredData();
 279                 $this->makeFormattedData();
 280         }
 281
 282         /**#@+
 283          * @access private
 284          */
 285         /**
 286          * Generate a flat list of the exif tags
 287          */
 288         function makeFlatExifTags() {
 289                 $this->extractTags( $this->mExifTags );
 290         }
 291
 292         /**
 293          * A recursing extractor function used by makeFlatExifTags()
 294          *
 295          * Note: This used to use an array_walk function, but it made PHP5
 296          * segfault, see `cvs diff -u -r 1.4 -r 1.5 Exif.php`
 297          */
 298         function extractTags( &$tagset ) {
 299                 foreach( $tagset as $key => $val ) {
 300                         if( is_array( $val ) ) {
 301                                 $this->extractTags( $val );
 302                         } else {
 303                                 $this->mFlatExifTags[$key] = $val;
 304                         }
 305                 }
 306         }
 307
 308         /**#@-*/
 309
 310         /**
 311          * Make $this->mFilteredExifData
 312          */
 313         function makeFilteredData() {
 314                 $this->mFilteredExifData = $this->mRawExifData;
 315
 316                 foreach( $this->mFilteredExifData as $k => $v ) {
 317                         if ( !in_array( $k, array_keys( $this->mFlatExifTags ) ) ) {
 318                                 $this->debug( $v, __FUNCTION__, "'$k' is not a valid Exif tag" );
 319                                 unset( $this->mFilteredExifData[$k] );
 320                         }
 321                 }
 322
 323                 foreach( $this->mFilteredExifData as $k => $v ) {
 324                         if ( !$this->validate($k, $v) ) {
 325                                 $this->debug( $v, __FUNCTION__, "'$k' contained invalid data" );
 326                                 unset( $this->mFilteredExifData[$k] );
 327                         }
 328                 }
 329         }
 330
 331         function makeFormattedData( $data = null ) {
 332                 $format = new FormatExif( $this->getFilteredData() );
 333                 $this->mFormattedExifData = $format->getFormattedData();
 334         }
 335         /**#@-*/
 336
 337         /**#@+
 338          * @return array
 339          */
 340         /**
 341          * Get $this->mRawExifData
 342          */
 343         function getData() {
 344                 return $this->mRawExifData;
 345         }
 346
 347         /**
 348          * Get $this->mFilteredExifData
 349          */
 350         function getFilteredData() {
 351                 return $this->mFilteredExifData;
 352         }
 353
 354         /**
 355          * Get $this->mFormattedExifData
 356          */
 357         function getFormattedData() {
 358                 return $this->mFormattedExifData;
 359         }
 360         /**#@-*/
 361
 362         /**
 363          * The version of the output format
 364          *
 365          * Before the actual metadata information is saved in the database we
 366          * strip some of it since we don't want to save things like thumbnails
 367          * which usually accompany Exif data. This value gets saved in the
 368          * database along with the actual Exif data, and if the version in the
 369          * database doesn't equal the value returned by this function the Exif
 370          * data is regenerated.
 371          *
 372          * @return int
 373          */
 374         function version() {
 375                 return 1; // We don't need no bloddy constants!
 376         }
 377
 378         /**#@+
 379          * Validates if a tag value is of the type it should be according to the Exif spec
 380          *
 381          * @param mixed $in The input value to check
 382          * @return bool
 383          */
 384         function isByte( $in ) {
 385                 if ( sprintf('%d', $in) == $in && $in >= 0 && $in <= 255 ) {
 386                         $this->debug( $in, __FUNCTION__, true );
 387                         return true;
 388                 } else {
 389                         $this->debug( $in, __FUNCTION__, false );
 390                         return false;
 391                 }
 392         }
 393
 394         function isASCII( $in ) {
 395                 if ( preg_match( "/[^\x0a\x20-\x7e]/", $in ) ) {
 396                         $this->debug( $in, __FUNCTION__, 'found a character not in our whitelist' );
 397                         return false;
 398                 }
 399
 400                 if ( preg_match( "/^\s*$/", $in ) ) {
 401                         $this->debug( $in, __FUNCTION__, 'input consisted solely of whitespace' );
 402                         return false;
 403                 }
 404
 405                 if ( strlen($in) > 1024 ) { // TODO: This might not be according to the spec
 406                         $this->debug( $in, __FUNCTION__, 'input was too long' );
 407                         return false;
 408                 }
 409
 410                 return true;
 411         }
 412
 413         function isShort( $in ) {
 414                 if ( sprintf('%d', $in) == $in && $in >= 0 && $in <= 65536 ) {
 415                         $this->debug( $in, __FUNCTION__, true );
 416                         return true;
 417                 } else {
 418                         $this->debug( $in, __FUNCTION__, false );
 419                         return false;
 420                 }
 421         }
 422
 423         function isLong( $in ) {
 424                 if ( sprintf('%d', $in) == $in && $in >= 0 && $in <= 4294967296 ) {
 425                         $this->debug( $in, __FUNCTION__, true );
 426                         return true;
 427                 } else {
 428                         $this->debug( $in, __FUNCTION__, false );
 429                         return false;
 430                 }
 431         }
 432
 433         function isRational( $in ) {
 434                 if ( @preg_match( "/^(\d+)\/(\d+[1-9]|[1-9]\d*)$/", $in, $m ) ) { # Avoid division by zero
 435                         return $this->isLong( $m[1] ) && $this->isLong( $m[2] );
 436                 } else {
 437                         $this->debug( $in, __FUNCTION__, 'fed a non-fraction value' );
 438                         return false;
 439                 }
 440         }
 441
 442         function isUndefined( $in ) {
 443                 if ( preg_match( "/^\d{4}$/", $in ) ) { // Allow ExifVersion and FlashpixVersion
 444                         $this->debug( $in, __FUNCTION__, true );
 445                         return true;
 446                 } else {
 447                         $this->debug( $in, __FUNCTION__, false );
 448                         return false;
 449                 }
 450         }
 451
 452         function isSlong( $in ) {
 453                 if ( $this->isLong( abs( $in ) ) ) {
 454                         $this->debug( $in, __FUNCTION__, true );
 455                         return true;
 456                 } else {
 457                         $this->debug( $in, __FUNCTION__, false );
 458                         return false;
 459                 }
 460         }
 461
 462         function isSrational( $in ) {
 463                 if ( preg_match( "/^(\d+)\/(\d+[1-9]|[1-9]\d*)$/", $in, $m ) ) { # Avoid division by zero
 464                         return $this->isSlong( $m[0] ) && $this->isSlong( $m[1] );
 465                 } else {
 466                         $this->debug( $in, __FUNCTION__, 'fed a non-fraction value' );
 467                         return false;
 468                 }
 469         }
 470         /**#@-*/
 471
 472         /**
 473          * Validates if a tag has a legal value according to the Exif spec
 474          *
 475          * @param string $tag The tag to check
 476          * @param mixed  $val The value of the tag
 477          * @return bool
 478          */
 479         function validate( $tag, $val ) {
 480                 $debug = "tag is '$tag'";
 481                 // Fucks up if not typecast
 482                 switch( (string)$this->mFlatExifTags[$tag] ) {
 483                         case (string)MW_EXIF_BYTE:
 484                                 $this->debug( $val, __FUNCTION__, $debug );
 485                                 return $this->isByte( $val );
 486                         case (string)MW_EXIF_ASCII:
 487                                 $this->debug( $val, __FUNCTION__, $debug );
 488                                 return $this->isASCII( $val );
 489                         case (string)MW_EXIF_SHORT:
 490                                 $this->debug( $val, __FUNCTION__, $debug );
 491                                 return $this->isShort( $val );
 492                         case (string)MW_EXIF_LONG:
 493                                 $this->debug( $val, __FUNCTION__, $debug );
 494                                 return $this->isLong( $val );
 495                         case (string)MW_EXIF_RATIONAL:
 496                                 $this->debug( $val, __FUNCTION__, $debug );
 497                                 return $this->isRational( $val );
 498                         case (string)MW_EXIF_UNDEFINED:
 499                                 $this->debug( $val, __FUNCTION__, $debug );
 500                                 return $this->isUndefined( $val );
 501                         case (string)MW_EXIF_SLONG:
 502                                 $this->debug( $val, __FUNCTION__, $debug );
 503                                 return $this->isSlong( $val );
 504                         case (string)MW_EXIF_SRATIONAL:
 505                                 $this->debug( $val, __FUNCTION__, $debug );
 506                                 return $this->isSrational( $val );
 507                         case (string)MW_EXIF_SHORT.','.MW_EXIF_LONG:
 508                                 $this->debug( $val, __FUNCTION__, $debug );
 509                                 return $this->isShort( $val ) || $this->isLong( $val );
 510                         default:
 511                                 $this->debug( $val, __FUNCTION__, "The tag '$tag' is unknown" );
 512                                 return false;
 513                 }
 514         }
 515
 516         /**
 517          * Conviniance function for debugging output
 518          *
 519          * @param mixed $in
 520          * @param string $fname
 521          * @param mixed $action
 522          */
 523          function debug( $in, $fname, $action = null ) {
 524                 $type = gettype( $in );
 525                 $class = ucfirst( __CLASS__ );
 526                 if ( $type === 'array' )
 527                         $in = print_r( $in, true );
 528
 529                 if ( $action === true )
 530                         wfDebug( "$class::$fname: accepted: '$in' (type: $type)\n");
 531                 elseif ( $action === false )
 532                         wfDebug( "$class::$fname: rejected: '$in' (type: $type)\n");
 533                 elseif ( $action === null )
 534                         wfDebug( "$class::$fname: input was: '$in' (type: $type)\n");
 535                 else
 536                         wfDebug( "$class::$fname: $action (type: $type; content: '$in')\n");
 537         }
 538
 539 }
 540
 541 /**
 542  * @package MediaWiki
 543  * @subpackage Metadata
 544  */
 545 class FormatExif {
 546         /**
 547          * The Exif data to format
 548          *
 549          * @var array
 550          * @access private
 551          */
 552         var $mExif;
 553
 554         /**
 555          * Constructor
 556          *
 557          * @param array $exif The Exif data to format ( as returned by
 558          *                    Exif::getFilteredData() )
 559          */
 560         function FormatExif( $exif ) {
 561                 $this->mExif = $exif;
 562         }
 563
 564         /**
 565          * Numbers given by Exif user agents are often magical, that is they
 566          * should be replaced by a detailed explanation depending on their
 567          * value which most of the time are plain integers. This function
 568          * formats Exif values into human readable form.
 569          *
 570          * @return array
 571          */
 572         function getFormattedData() {
 573                 global $wgLang;
 574
 575                 $tags =& $this->mExif;
 576
 577                 foreach( $tags as $tag => $val ) {
 578                         switch( $tag ) {
 579                         case 'Compression':
 580                                 switch( $val ) {
 581                                 case 1: case 6:
 582                                         $tags[$tag] = $this->msg( $tag, $val );
 583                                         break;
 584                                 default:
 585                                         $tags[$tag] = $val;
 586                                         break;
 587                                 }
 588                                 break;
 589
 590                         case 'PhotometricInterpretation':
 591                                 switch( $val ) {
 592                                 case 2: case 6:
 593                                         $tags[$tag] = $this->msg( $tag, $val );
 594                                         break;
 595                                 default:
 596                                         $tags[$tag] = $val;
 597                                         break;
 598                                 }
 599                                 break;
 600
 601                         case 'Orientation':
 602                                 switch( $val ) {
 603                                 case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 8:
 604                                         $tags[$tag] = $this->msg( $tag, $val );
 605                                         break;
 606                                 default:
 607                                         $tags[$tag] = $val;
 608                                         break;
 609                                 }
 610                                 break;
 611
 612                         case 'PlanarConfiguration':
 613                                 switch( $val ) {
 614                                 case 1: case 2:
 615                                         $tags[$tag] = $this->msg( $tag, $val );
 616                                         break;
 617                                 default:
 618                                         $tags[$tag] = $val;
 619                                         break;
 620                                 }
 621                                 break;
 622
 623                         // TODO: YCbCrSubSampling
 624                         // TODO: YCbCrPositioning
 625                         // TODO: If this field does not exists use 2
 626                         case 'ResolutionUnit': #p26
 627                                 switch( $val ) {
 628                                 case 2: case 3:
 629                                         $tags[$tag] = $this->msg( $tag, $val );
 630                                         break;
 631                                 default:
 632                                         $tags[$tag] = $val;
 633                                         break;
 634                                 }
 635                                 break;
 636
 637                         // TODO: YCbCrCoefficients  #p27 (see annex E)
 638                         case 'ExifVersion': case 'FlashpixVersion':
 639                                 $tags[$tag] = "$val"/100;
 640                                 break;
 641
 642                         case 'ColorSpace':
 643                                 switch( $val ) {
 644                                 case 1: case 'FFFF.H':
 645                                         $tags[$tag] = $this->msg( $tag, $val );
 646                                         break;
 647                                 default:
 648                                         $tags[$tag] = $val;
 649                                         break;
 650                                 }
 651                                 break;
 652
 653                         case 'ComponentsConfiguration':
 654                                 switch( $val ) {
 655                                 case 0: case 1: case 2: case 3: case 4: case 5: case 6:
 656                                         $tags[$tag] = $this->msg( $tag, $val );
 657                                         break;
 658                                 default:
 659                                         $tags[$tag] = $val;
 660                                         break;
 661                                 }
 662                                 break;
 663
 664                         case 'DateTime':
 665                         case 'DateTimeOriginal':
 666                         case 'DateTimeDigitized':
 667                                 $tags[$tag] = $wgLang->timeanddate( wfTimestamp(TS_MW, $val) );
 668                                 break;
 669
 670                         case 'ExposureProgram':
 671                                 switch( $val ) {
 672                                 case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 8:
 673                                         $tags[$tag] = $this->msg( $tag, $val );
 674                                         break;
 675                                 default:
 676                                         $tags[$tag] = $val;
 677                                         break;
 678                                 }
 679                                 break;
 680
 681                         case 'MeteringMode':
 682                                 switch( $val ) {
 683                                 case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 255:
 684                                         $tags[$tag] = $this->msg( $tag, $val );
 685                                         break;
 686                                 default:
 687                                         $tags[$tag] = $val;
 688                                         break;
 689                                 }
 690                                 break;
 691
 692                         case 'LightSource':
 693                                 switch( $val ) {
 694                                 case 0: case 1: case 2: case 3: case 4: case 9: case 10: case 11:
 695                                 case 12: case 13: case 14: case 15: case 17: case 18: case 19: case 20:
 696                                 case 21: case 22: case 23: case 24: case 255:
 697                                         $tags[$tag] = $this->msg( $tag, $val );
 698                                         break;
 699                                 default:
 700                                         $tags[$tag] = $val;
 701                                         break;
 702                                 }
 703                                 break;
 704
 705                         // TODO: Flash
 706                         case 'FocalPlaneResolutionUnit':
 707                                 switch( $val ) {
 708                                 case 2:
 709                                         $tags[$tag] = $this->msg( $tag, $val );
 710                                         break;
 711                                 default:
 712                                         $tags[$tag] = $val;
 713                                         break;
 714                                 }
 715                                 break;
 716
 717                         case 'SensingMethod':
 718                                 switch( $val ) {
 719                                 case 1: case 2: case 3: case 4: case 5: case 7: case 8:
 720                                         $tags[$tag] = $this->msg( $tag, $val );
 721                                         break;
 722                                 default:
 723                                         $tags[$tag] = $val;
 724                                         break;
 725                                 }
 726                                 break;
 727
 728                         case 'FileSource':
 729                                 switch( $val ) {
 730                                 case 3:
 731                                         $tags[$tag] = $this->msg( $tag, $val );
 732                                         break;
 733                                 default:
 734                                         $tags[$tag] = $val;
 735                                         break;
 736                                 }
 737                                 break;
 738
 739                         case 'SceneType':
 740                                 switch( $val ) {
 741                                 case 1:
 742                                         $tags[$tag] = $this->msg( $tag, $val );
 743                                         break;
 744                                 default:
 745                                         $tags[$tag] = $val;
 746                                         break;
 747                                 }
 748                                 break;
 749
 750                         case 'CustomRendered':
 751                                 switch( $val ) {
 752                                 case 0: case 1:
 753                                         $tags[$tag] = $this->msg( $tag, $val );
 754                                         break;
 755                                 default:
 756                                         $tags[$tag] = $val;
 757                                         break;
 758                                 }
 759                                 break;
 760
 761                         case 'ExposureMode':
 762                                 switch( $val ) {
 763                                 case 0: case 1: case 2:
 764                                         $tags[$tag] = $this->msg( $tag, $val );
 765                                         break;
 766                                 default:
 767                                         $tags[$tag] = $val;
 768                                         break;
 769                                 }
 770                                 break;
 771
 772                         case 'WhiteBalance':
 773                                 switch( $val ) {
 774                                 case 0: case 1:
 775                                         $tags[$tag] = $this->msg( $tag, $val );
 776                                         break;
 777                                 default:
 778                                         $tags[$tag] = $val;
 779                                         break;
 780                                 }
 781                                 break;
 782
 783                         case 'SceneCaptureType':
 784                                 switch( $val ) {
 785                                 case 0: case 1: case 2: case 3:
 786                                         $tags[$tag] = $this->msg( $tag, $val );
 787                                         break;
 788                                 default:
 789                                         $tags[$tag] = $val;
 790                                         break;
 791                                 }
 792                                 break;
 793
 794                         case 'GainControl':
 795                                 switch( $val ) {
 796                                 case 0: case 1: case 2: case 3: case 4:
 797                                         $tags[$tag] = $this->msg( $tag, $val );
 798                                         break;
 799                                 default:
 800                                         $tags[$tag] = $val;
 801                                         break;
 802                                 }
 803                                 break;
 804
 805                         case 'Contrast':
 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 'Saturation':
 817                                 switch( $val ) {
 818                                 case 0: case 1: case 2:
 819                                         $tags[$tag] = $this->msg( $tag, $val );
 820                                         break;
 821                                 default:
 822                                         $tags[$tag] = $val;
 823                                         break;
 824                                 }
 825                                 break;
 826
 827                         case 'Sharpness':
 828                                 switch( $val ) {
 829                                 case 0: case 1: case 2:
 830                                         $tags[$tag] = $this->msg( $tag, $val );
 831                                         break;
 832                                 default:
 833                                         $tags[$tag] = $val;
 834                                         break;
 835                                 }
 836                                 break;
 837
 838                         case 'SubjectDistanceRange':
 839                                 switch( $val ) {
 840                                 case 0: case 1: case 2: case 3:
 841                                         $tags[$tag] = $this->msg( $tag, $val );
 842                                         break;
 843                                 default:
 844                                         $tags[$tag] = $val;
 845                                         break;
 846                                 }
 847                                 break;
 848
 849                         case 'GPSLatitudeRef':
 850                         case 'GPSDestLatitudeRef':
 851                                 switch( $val ) {
 852                                 case 'N': case 'S':
 853                                         $tags[$tag] = $this->msg( 'GPSLatitude', $val );
 854                                         break;
 855                                 default:
 856                                         $tags[$tag] = $val;
 857                                         break;
 858                                 }
 859                                 break;
 860
 861                         case 'GPSLongitudeRef':
 862                         case 'GPSDestLongitudeRef':
 863                                 switch( $val ) {
 864                                 case 'E': case 'W':
 865                                         $tags[$tag] = $this->msg( 'GPSLongitude', $val );
 866                                         break;
 867                                 default:
 868                                         $tags[$tag] = $val;
 869                                         break;
 870                                 }
 871                                 break;
 872
 873                         case 'GPSStatus':
 874                                 switch( $val ) {
 875                                 case 'A': case 'V':
 876                                         $tags[$tag] = $this->msg( $tag, $val );
 877                                         break;
 878                                 default:
 879                                         $tags[$tag] = $val;
 880                                         break;
 881                                 }
 882                                 break;
 883
 884                         case 'GPSMeasureMode':
 885                                 switch( $val ) {
 886                                 case 2: case 3:
 887                                         $tags[$tag] = $this->msg( $tag, $val );
 888                                         break;
 889                                 default:
 890                                         $tags[$tag] = $val;
 891                                         break;
 892                                 }
 893                                 break;
 894
 895                         case 'GPSSpeedRef':
 896                         case 'GPSDestDistanceRef':
 897                                 switch( $val ) {
 898                                 case 'K': case 'M': case 'N':
 899                                         $tags[$tag] = $this->msg( 'GPSSpeed', $val );
 900                                         break;
 901                                 default:
 902                                         $tags[$tag] = $val;
 903                                         break;
 904                                 }
 905                                 break;
 906
 907                         case 'GPSTrackRef':
 908                         case 'GPSImgDirectionRef':
 909                         case 'GPSDestBearingRef':
 910                                 switch( $val ) {
 911                                 case 'T': case 'M':
 912                                         $tags[$tag] = $this->msg( 'GPSDirection', $val );
 913                                         break;
 914                                 default:
 915                                         $tags[$tag] = $val;
 916                                         break;
 917                                 }
 918                                 break;
 919
 920                         case 'GPSDateStamp':
 921                                 $tags[$tag] = $wgLang->date( substr( $val, 0, 4 ) . substr( $val, 5, 2 ) . substr( $val, 8, 2 ) . '000000' );
 922                                 break;
 923
 924                         // This is not in the Exif standard, just a special
 925                         // case for our purposes which enables wikis to wikify
 926                         // the make, model and software name to link to their articles.
 927                         case 'Make':
 928                         case 'Model':
 929                         case 'Software':
 930                                 $tags[$tag] = wfMsg( strtolower( "exif-$tag-value" ), $val );
 931                                 break;
 932                         default:
 933                                 if ( preg_match( '/^(\d+)\/(\d+)$/', $val, $m ) ) {
 934                                         $tags[$tag] = $m[2] != 0 ? $m[1]/$m[2] : $val;
 935                                         break;
 936                                 }
 937                                 $tags[$tag] = $val;
 938                                 break;
 939                         }
 940                 }
 941
 942                 return $tags;
 943         }
 944
 945         /**
 946          * Conviniance function for format()
 947          *
 948          * @param string $tag The tag name to pass on
 949          * @param string $val The value of the tag
 950          * @return string A wfMsg of "exif-$tag-$val" in lower case
 951          */
 952         function msg( $tag, $val ) {
 953                 return wfMsg( strtolower("exif-$tag-$val") );
 954         }
 955 }