* @copyright Copyright © 2005, Ævar Arnfjörð Bjarmason, 2009 Brent Garber * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License * @see http://exif.org/Exif2-2.PDF The Exif 2.2 specification * @file */ /** * Class to extract and validate Exif data from jpeg (and possibly tiff) files. * @ingroup Media */ class Exif { /** An 8-bit (1-byte) unsigned integer. */ const BYTE = 1; /** An 8-bit byte containing one 7-bit ASCII code. * The final byte is terminated with NULL. */ const ASCII = 2; /** A 16-bit (2-byte) unsigned integer. */ const SHORT = 3; /** A 32-bit (4-byte) unsigned integer. */ const LONG = 4; /** Two LONGs. The first LONG is the numerator and the second LONG expresses * the denominator */ const RATIONAL = 5; /** A 16-bit (2-byte) or 32-bit (4-byte) unsigned integer. */ const SHORT_OR_LONG = 6; /** An 8-bit byte that can take any value depending on the field definition */ const UNDEFINED = 7; /** A 32-bit (4-byte) signed integer (2's complement notation), */ const SLONG = 9; /** Two SLONGs. The first SLONG is the numerator and the second SLONG is * the denominator. */ const SRATIONAL = 10; /** A fake value for things we don't want or don't support. */ const IGNORE = -1; /** @var array Exif tags grouped by category, the tagname itself is the key * and the type is the value, in the case of more than one possible value * type they are separated by commas. */ private $mExifTags; /** @var array The raw Exif data returned by exif_read_data() */ private $mRawExifData; /** @var array A Filtered version of $mRawExifData that has been pruned * of invalid tags and tags that contain content they shouldn't contain * according to the Exif specification */ private $mFilteredExifData; /** @var string The file being processed */ private $file; /** @var string The basename of the file being processed */ private $basename; /** @var string The private log to log to, e.g. 'exif' */ private $log = false; /** @var string The byte order of the file. Needed because php's extension * doesn't fully process some obscure props. */ private $byteOrder; /** * Constructor * * @param string $file Filename. * @param string $byteOrder Type of byte ordering either 'BE' (Big Endian) * or 'LE' (Little Endian). Default ''. * @throws MWException * @todo FIXME: The following are broke: * SubjectArea. Need to test the more obscure tags. * DigitalZoomRatio = 0/0 is rejected. need to determine if that's valid. * Possibly should treat 0/0 = 0. need to read exif spec on that. */ function __construct( $file, $byteOrder = '' ) { /** * Page numbers here refer to pages in the Exif 2.2 standard * * Note, Exif::UNDEFINED is treated as a string, not as an array of bytes * so don't put a count parameter for any UNDEFINED values. * * @link http://exif.org/Exif2-2.PDF The Exif 2.2 specification */ $this->mExifTags = array( # TIFF Rev. 6.0 Attribute Information (p22) 'IFD0' => array( # Tags relating to image structure 'ImageWidth' => Exif::SHORT_OR_LONG, # Image width 'ImageLength' => Exif::SHORT_OR_LONG, # Image height 'BitsPerSample' => array( Exif::SHORT, 3 ), # Number of bits per component # "When a primary image is JPEG compressed, this designation is not" # "necessary and is omitted." (p23) 'Compression' => Exif::SHORT, # Compression scheme #p23 'PhotometricInterpretation' => Exif::SHORT, # Pixel composition #p23 'Orientation' => Exif::SHORT, # Orientation of image #p24 'SamplesPerPixel' => Exif::SHORT, # Number of components 'PlanarConfiguration' => Exif::SHORT, # Image data arrangement #p24 'YCbCrSubSampling' => array( Exif::SHORT, 2 ), # Subsampling ratio of Y to C #p24 'YCbCrPositioning' => Exif::SHORT, # Y and C positioning #p24-25 'XResolution' => Exif::RATIONAL, # Image resolution in width direction 'YResolution' => Exif::RATIONAL, # Image resolution in height direction 'ResolutionUnit' => Exif::SHORT, # Unit of X and Y resolution #(p26) # Tags relating to recording offset 'StripOffsets' => Exif::SHORT_OR_LONG, # Image data location 'RowsPerStrip' => Exif::SHORT_OR_LONG, # Number of rows per strip 'StripByteCounts' => Exif::SHORT_OR_LONG, # Bytes per compressed strip 'JPEGInterchangeFormat' => Exif::SHORT_OR_LONG, # Offset to JPEG SOI 'JPEGInterchangeFormatLength' => Exif::SHORT_OR_LONG, # Bytes of JPEG data # Tags relating to image data characteristics 'TransferFunction' => Exif::IGNORE, # Transfer function 'WhitePoint' => array( Exif::RATIONAL, 2 ), # White point chromaticity 'PrimaryChromaticities' => array( Exif::RATIONAL, 6 ), # Chromaticities of primarities # Color space transformation matrix coefficients #p27 'YCbCrCoefficients' => array( Exif::RATIONAL, 3 ), 'ReferenceBlackWhite' => array( Exif::RATIONAL, 6 ), # Pair of black and white reference values # Other tags 'DateTime' => Exif::ASCII, # File change date and time 'ImageDescription' => Exif::ASCII, # Image title 'Make' => Exif::ASCII, # Image input equipment manufacturer 'Model' => Exif::ASCII, # Image input equipment model 'Software' => Exif::ASCII, # Software used 'Artist' => Exif::ASCII, # Person who created the image 'Copyright' => Exif::ASCII, # Copyright holder ), # Exif IFD Attribute Information (p30-31) 'EXIF' => array( # @todo NOTE: Nonexistence of this field is taken to mean nonconformance # to the Exif 2.1 AND 2.2 standards 'ExifVersion' => Exif::UNDEFINED, # Exif version 'FlashPixVersion' => Exif::UNDEFINED, # Supported Flashpix version #p32 # Tags relating to Image Data Characteristics 'ColorSpace' => Exif::SHORT, # Color space information #p32 # Tags relating to image configuration 'ComponentsConfiguration' => Exif::UNDEFINED, # Meaning of each component #p33 'CompressedBitsPerPixel' => Exif::RATIONAL, # Image compression mode 'PixelYDimension' => Exif::SHORT_OR_LONG, # Valid image width 'PixelXDimension' => Exif::SHORT_OR_LONG, # Valid image height # Tags relating to related user information 'MakerNote' => Exif::IGNORE, # Manufacturer notes 'UserComment' => Exif::UNDEFINED, # User comments #p34 # Tags relating to related file information 'RelatedSoundFile' => Exif::ASCII, # Related audio file # Tags relating to date and time 'DateTimeOriginal' => Exif::ASCII, # Date and time of original data generation #p36 'DateTimeDigitized' => Exif::ASCII, # Date and time of original data generation 'SubSecTime' => Exif::ASCII, # DateTime subseconds 'SubSecTimeOriginal' => Exif::ASCII, # DateTimeOriginal subseconds 'SubSecTimeDigitized' => Exif::ASCII, # DateTimeDigitized subseconds # Tags relating to picture-taking conditions (p31) 'ExposureTime' => Exif::RATIONAL, # Exposure time 'FNumber' => Exif::RATIONAL, # F Number 'ExposureProgram' => Exif::SHORT, # Exposure Program #p38 'SpectralSensitivity' => Exif::ASCII, # Spectral sensitivity 'ISOSpeedRatings' => Exif::SHORT, # ISO speed rating 'OECF' => Exif::IGNORE, # Optoelectronic conversion factor. Note: We don't have support for this atm. 'ShutterSpeedValue' => Exif::SRATIONAL, # Shutter speed 'ApertureValue' => Exif::RATIONAL, # Aperture 'BrightnessValue' => Exif::SRATIONAL, # Brightness 'ExposureBiasValue' => Exif::SRATIONAL, # Exposure bias 'MaxApertureValue' => Exif::RATIONAL, # Maximum land aperture 'SubjectDistance' => Exif::RATIONAL, # Subject distance 'MeteringMode' => Exif::SHORT, # Metering mode #p40 'LightSource' => Exif::SHORT, # Light source #p40-41 'Flash' => Exif::SHORT, # Flash #p41-42 'FocalLength' => Exif::RATIONAL, # Lens focal length 'SubjectArea' => array( Exif::SHORT, 4 ), # Subject area 'FlashEnergy' => Exif::RATIONAL, # Flash energy 'SpatialFrequencyResponse' => Exif::IGNORE, # Spatial frequency response. Not supported atm. 'FocalPlaneXResolution' => Exif::RATIONAL, # Focal plane X resolution 'FocalPlaneYResolution' => Exif::RATIONAL, # Focal plane Y resolution 'FocalPlaneResolutionUnit' => Exif::SHORT, # Focal plane resolution unit #p46 'SubjectLocation' => array( Exif::SHORT, 2 ), # Subject location 'ExposureIndex' => Exif::RATIONAL, # Exposure index 'SensingMethod' => Exif::SHORT, # Sensing method #p46 'FileSource' => Exif::UNDEFINED, # File source #p47 'SceneType' => Exif::UNDEFINED, # Scene type #p47 'CFAPattern' => Exif::IGNORE, # CFA pattern. not supported atm. 'CustomRendered' => Exif::SHORT, # Custom image processing #p48 'ExposureMode' => Exif::SHORT, # Exposure mode #p48 'WhiteBalance' => Exif::SHORT, # White Balance #p49 'DigitalZoomRatio' => Exif::RATIONAL, # Digital zoom ration 'FocalLengthIn35mmFilm' => Exif::SHORT, # Focal length in 35 mm film 'SceneCaptureType' => Exif::SHORT, # Scene capture type #p49 'GainControl' => Exif::SHORT, # Scene control #p49-50 'Contrast' => Exif::SHORT, # Contrast #p50 'Saturation' => Exif::SHORT, # Saturation #p50 'Sharpness' => Exif::SHORT, # Sharpness #p50 'DeviceSettingDescription' => Exif::IGNORE, # Device settings description. This could maybe be supported. Need to find an # example file that uses this to see if it has stuff of interest in it. 'SubjectDistanceRange' => Exif::SHORT, # Subject distance range #p51 'ImageUniqueID' => Exif::ASCII, # Unique image ID ), # GPS Attribute Information (p52) 'GPS' => array( 'GPSVersion' => Exif::UNDEFINED, # Should be an array of 4 Exif::BYTE's. However php treats it as an undefined # Note exif standard calls this GPSVersionID, but php doesn't like the id suffix 'GPSLatitudeRef' => Exif::ASCII, # North or South Latitude #p52-53 'GPSLatitude' => array( Exif::RATIONAL, 3 ), # Latitude 'GPSLongitudeRef' => Exif::ASCII, # East or West Longitude #p53 'GPSLongitude' => array( Exif::RATIONAL, 3 ), # Longitude 'GPSAltitudeRef' => Exif::UNDEFINED, # Altitude reference. Note, the exif standard says this should be an EXIF::Byte, # but php seems to disagree. 'GPSAltitude' => Exif::RATIONAL, # Altitude 'GPSTimeStamp' => array( Exif::RATIONAL, 3 ), # GPS time (atomic clock) 'GPSSatellites' => Exif::ASCII, # Satellites used for measurement 'GPSStatus' => Exif::ASCII, # Receiver status #p54 'GPSMeasureMode' => Exif::ASCII, # Measurement mode #p54-55 'GPSDOP' => Exif::RATIONAL, # Measurement precision 'GPSSpeedRef' => Exif::ASCII, # Speed unit #p55 'GPSSpeed' => Exif::RATIONAL, # Speed of GPS receiver 'GPSTrackRef' => Exif::ASCII, # Reference for direction of movement #p55 'GPSTrack' => Exif::RATIONAL, # Direction of movement 'GPSImgDirectionRef' => Exif::ASCII, # Reference for direction of image #p56 'GPSImgDirection' => Exif::RATIONAL, # Direction of image 'GPSMapDatum' => Exif::ASCII, # Geodetic survey data used 'GPSDestLatitudeRef' => Exif::ASCII, # Reference for latitude of destination #p56 'GPSDestLatitude' => array( Exif::RATIONAL, 3 ), # Latitude destination 'GPSDestLongitudeRef' => Exif::ASCII, # Reference for longitude of destination #p57 'GPSDestLongitude' => array( Exif::RATIONAL, 3 ), # Longitude of destination 'GPSDestBearingRef' => Exif::ASCII, # Reference for bearing of destination #p57 'GPSDestBearing' => Exif::RATIONAL, # Bearing of destination 'GPSDestDistanceRef' => Exif::ASCII, # Reference for distance to destination #p57-58 'GPSDestDistance' => Exif::RATIONAL, # Distance to destination 'GPSProcessingMethod' => Exif::UNDEFINED, # Name of GPS processing method 'GPSAreaInformation' => Exif::UNDEFINED, # Name of GPS area 'GPSDateStamp' => Exif::ASCII, # GPS date 'GPSDifferential' => Exif::SHORT, # GPS differential correction ), ); $this->file = $file; $this->basename = wfBaseName( $this->file ); if ( $byteOrder === 'BE' || $byteOrder === 'LE' ) { $this->byteOrder = $byteOrder; } else { // Only give a warning for b/c, since originally we didn't // require this. The number of things affected by this is // rather small. wfWarn( 'Exif class did not have byte order specified. ' . 'Some properties may be decoded incorrectly.' ); $this->byteOrder = 'BE'; // BE seems about twice as popular as LE in jpg's. } $this->debugFile( $this->basename, __FUNCTION__, true ); if ( function_exists( 'exif_read_data' ) ) { wfSuppressWarnings(); $data = exif_read_data( $this->file, 0, true ); wfRestoreWarnings(); } else { throw new MWException( "Internal error: exif_read_data not present. " . "\$wgShowEXIF may be incorrectly set or not checked by an extension." ); } /** * exif_read_data() will return false on invalid input, such as * when somebody uploads a file called something.jpeg * containing random gibberish. */ $this->mRawExifData = $data ?: array(); $this->makeFilteredData(); $this->collapseData(); $this->debugFile( __FUNCTION__, false ); } /** * Make $this->mFilteredExifData */ function makeFilteredData() { $this->mFilteredExifData = array(); foreach ( array_keys( $this->mRawExifData ) as $section ) { if ( !array_key_exists( $section, $this->mExifTags ) ) { $this->debug( $section, __FUNCTION__, "'$section' is not a valid Exif section" ); continue; } foreach ( array_keys( $this->mRawExifData[$section] ) as $tag ) { if ( !array_key_exists( $tag, $this->mExifTags[$section] ) ) { $this->debug( $tag, __FUNCTION__, "'$tag' is not a valid tag in '$section'" ); continue; } $this->mFilteredExifData[$tag] = $this->mRawExifData[$section][$tag]; // This is ok, as the tags in the different sections do not conflict. // except in computed and thumbnail section, which we don't use. $value = $this->mRawExifData[$section][$tag]; if ( !$this->validate( $section, $tag, $value ) ) { $this->debug( $value, __FUNCTION__, "'$tag' contained invalid data" ); unset( $this->mFilteredExifData[$tag] ); } } } } /** * Collapse some fields together. * This converts some fields from exif form, to a more friendly form. * For example GPS latitude to a single number. * * The rationale behind this is that we're storing data, not presenting to the user * For example a longitude is a single number describing how far away you are from * the prime meridian. Well it might be nice to split it up into minutes and seconds * for the user, it doesn't really make sense to split a single number into 4 parts * for storage. (degrees, minutes, second, direction vs single floating point number). * * Other things this might do (not really sure if they make sense or not): * Dates -> mediawiki date format. * convert values that can be in different units to be in one standardized unit. * * As an alternative approach, some of this could be done in the validate phase * if we make up our own types like Exif::DATE. */ function collapseData() { $this->exifGPStoNumber( 'GPSLatitude' ); $this->exifGPStoNumber( 'GPSDestLatitude' ); $this->exifGPStoNumber( 'GPSLongitude' ); $this->exifGPStoNumber( 'GPSDestLongitude' ); if ( isset( $this->mFilteredExifData['GPSAltitude'] ) && isset( $this->mFilteredExifData['GPSAltitudeRef'] ) ) { // We know altitude data is a / from the validation // functions ran earlier. But multiplying such a string by -1 // doesn't work well, so convert. list( $num, $denom ) = explode( '/', $this->mFilteredExifData['GPSAltitude'] ); $this->mFilteredExifData['GPSAltitude'] = $num / $denom; if ( $this->mFilteredExifData['GPSAltitudeRef'] === "\1" ) { $this->mFilteredExifData['GPSAltitude'] *= -1; } unset( $this->mFilteredExifData['GPSAltitudeRef'] ); } $this->exifPropToOrd( 'FileSource' ); $this->exifPropToOrd( 'SceneType' ); $this->charCodeString( 'UserComment' ); $this->charCodeString( 'GPSProcessingMethod' ); $this->charCodeString( 'GPSAreaInformation' ); //ComponentsConfiguration should really be an array instead of a string... //This turns a string of binary numbers into an array of numbers. if ( isset( $this->mFilteredExifData['ComponentsConfiguration'] ) ) { $val = $this->mFilteredExifData['ComponentsConfiguration']; $ccVals = array(); $strLen = strlen( $val ); for ( $i = 0; $i < $strLen; $i++ ) { $ccVals[$i] = ord( substr( $val, $i, 1 ) ); } $ccVals['_type'] = 'ol'; //this is for formatting later. $this->mFilteredExifData['ComponentsConfiguration'] = $ccVals; } //GPSVersion(ID) is treated as the wrong type by php exif support. //Go through each byte turning it into a version string. //For example: "\x02\x02\x00\x00" -> "2.2.0.0" //Also change exif tag name from GPSVersion (what php exif thinks it is) //to GPSVersionID (what the exif standard thinks it is). if ( isset( $this->mFilteredExifData['GPSVersion'] ) ) { $val = $this->mFilteredExifData['GPSVersion']; $newVal = ''; $strLen = strlen( $val ); for ( $i = 0; $i < $strLen; $i++ ) { if ( $i !== 0 ) { $newVal .= '.'; } $newVal .= ord( substr( $val, $i, 1 ) ); } if ( $this->byteOrder === 'LE' ) { // Need to reverse the string $newVal2 = ''; for ( $i = strlen( $newVal ) - 1; $i >= 0; $i-- ) { $newVal2 .= substr( $newVal, $i, 1 ); } $this->mFilteredExifData['GPSVersionID'] = $newVal2; } else { $this->mFilteredExifData['GPSVersionID'] = $newVal; } unset( $this->mFilteredExifData['GPSVersion'] ); } } /** * Do userComment tags and similar. See pg. 34 of exif standard. * basically first 8 bytes is charset, rest is value. * This has not been tested on any shift-JIS strings. * @param string $prop Prop name */ private function charCodeString( $prop ) { if ( isset( $this->mFilteredExifData[$prop] ) ) { if ( strlen( $this->mFilteredExifData[$prop] ) <= 8 ) { //invalid. Must be at least 9 bytes long. $this->debug( $this->mFilteredExifData[$prop], __FUNCTION__, false ); unset( $this->mFilteredExifData[$prop] ); return; } $charCode = substr( $this->mFilteredExifData[$prop], 0, 8 ); $val = substr( $this->mFilteredExifData[$prop], 8 ); switch ( $charCode ) { case "\x4A\x49\x53\x00\x00\x00\x00\x00": //JIS $charset = "Shift-JIS"; break; case "UNICODE\x00": $charset = "UTF-16" . $this->byteOrder; break; default: //ascii or undefined. $charset = ""; break; } if ( $charset ) { wfSuppressWarnings(); $val = iconv( $charset, 'UTF-8//IGNORE', $val ); wfRestoreWarnings(); } else { // if valid utf-8, assume that, otherwise assume windows-1252 $valCopy = $val; UtfNormal::quickIsNFCVerify( $valCopy ); //validates $valCopy. if ( $valCopy !== $val ) { wfSuppressWarnings(); $val = iconv( 'Windows-1252', 'UTF-8//IGNORE', $val ); wfRestoreWarnings(); } } //trim and check to make sure not only whitespace. $val = trim( $val ); if ( strlen( $val ) === 0 ) { //only whitespace. $this->debug( $this->mFilteredExifData[$prop], __FUNCTION__, "$prop: Is only whitespace" ); unset( $this->mFilteredExifData[$prop] ); return; } //all's good. $this->mFilteredExifData[$prop] = $val; } } /** * Convert an Exif::UNDEFINED from a raw binary string * to its value. This is sometimes needed depending on * the type of UNDEFINED field * @param string $prop Name of property */ private function exifPropToOrd( $prop ) { if ( isset( $this->mFilteredExifData[$prop] ) ) { $this->mFilteredExifData[$prop] = ord( $this->mFilteredExifData[$prop] ); } } /** * Convert gps in exif form to a single floating point number * for example 10 degress 20`40`` S -> -10.34444 * @param string $prop A GPS coordinate exif tag name (like GPSLongitude) */ private function exifGPStoNumber( $prop ) { $loc =& $this->mFilteredExifData[$prop]; $dir =& $this->mFilteredExifData[$prop . 'Ref']; $res = false; if ( isset( $loc ) && isset( $dir ) && ( $dir === 'N' || $dir === 'S' || $dir === 'E' || $dir === 'W' ) ) { list( $num, $denom ) = explode( '/', $loc[0] ); $res = $num / $denom; list( $num, $denom ) = explode( '/', $loc[1] ); $res += ( $num / $denom ) * ( 1 / 60 ); list( $num, $denom ) = explode( '/', $loc[2] ); $res += ( $num / $denom ) * ( 1 / 3600 ); if ( $dir === 'S' || $dir === 'W' ) { $res *= -1; // make negative } } // update the exif records. if ( $res !== false ) { // using !== as $res could potentially be 0 $this->mFilteredExifData[$prop] = $res; unset( $this->mFilteredExifData[$prop . 'Ref'] ); } else { // if invalid unset( $this->mFilteredExifData[$prop] ); unset( $this->mFilteredExifData[$prop . 'Ref'] ); } } /**#@-*/ /**#@+ * @return array */ /** * Get $this->mRawExifData * @return array */ function getData() { return $this->mRawExifData; } /** * Get $this->mFilteredExifData * @return array */ function getFilteredData() { return $this->mFilteredExifData; } /**#@-*/ /** * The version of the output format * * Before the actual metadata information is saved in the database we * strip some of it since we don't want to save things like thumbnails * which usually accompany Exif data. This value gets saved in the * database along with the actual Exif data, and if the version in the * database doesn't equal the value returned by this function the Exif * data is regenerated. * * @return int */ public static function version() { return 2; // We don't need no bloddy constants! } /** * Validates if a tag value is of the type it should be according to the Exif spec * * @param mixed $in The input value to check * @return bool */ private function isByte( $in ) { if ( !is_array( $in ) && sprintf( '%d', $in ) == $in && $in >= 0 && $in <= 255 ) { $this->debug( $in, __FUNCTION__, true ); return true; } else { $this->debug( $in, __FUNCTION__, false ); return false; } } /** * @param mixed $in The input value to check * @return bool */ private function isASCII( $in ) { if ( is_array( $in ) ) { return false; } if ( preg_match( "/[^\x0a\x20-\x7e]/", $in ) ) { $this->debug( $in, __FUNCTION__, 'found a character not in our whitelist' ); return false; } if ( preg_match( '/^\s*$/', $in ) ) { $this->debug( $in, __FUNCTION__, 'input consisted solely of whitespace' ); return false; } return true; } /** * @param mixed $in The input value to check * @return bool */ private function isShort( $in ) { if ( !is_array( $in ) && sprintf( '%d', $in ) == $in && $in >= 0 && $in <= 65536 ) { $this->debug( $in, __FUNCTION__, true ); return true; } else { $this->debug( $in, __FUNCTION__, false ); return false; } } /** * @param mixed $in The input value to check * @return bool */ private function isLong( $in ) { if ( !is_array( $in ) && sprintf( '%d', $in ) == $in && $in >= 0 && $in <= 4294967296 ) { $this->debug( $in, __FUNCTION__, true ); return true; } else { $this->debug( $in, __FUNCTION__, false ); return false; } } /** * @param mixed $in The input value to check * @return bool */ private function isRational( $in ) { $m = array(); # Avoid division by zero if ( !is_array( $in ) && preg_match( '/^(\d+)\/(\d+[1-9]|[1-9]\d*)$/', $in, $m ) ) { return $this->isLong( $m[1] ) && $this->isLong( $m[2] ); } else { $this->debug( $in, __FUNCTION__, 'fed a non-fraction value' ); return false; } } /** * @param mixed $in The input value to check * @return bool */ private function isUndefined( $in ) { $this->debug( $in, __FUNCTION__, true ); return true; } /** * @param mixed $in The input value to check * @return bool */ private function isSlong( $in ) { if ( $this->isLong( abs( $in ) ) ) { $this->debug( $in, __FUNCTION__, true ); return true; } else { $this->debug( $in, __FUNCTION__, false ); return false; } } /** * @param mixed $in The input value to check * @return bool */ private function isSrational( $in ) { $m = array(); # Avoid division by zero if ( !is_array( $in ) && preg_match( '/^(-?\d+)\/(\d+[1-9]|[1-9]\d*)$/', $in, $m ) ) { return $this->isSlong( $m[0] ) && $this->isSlong( $m[1] ); } else { $this->debug( $in, __FUNCTION__, 'fed a non-fraction value' ); return false; } } /**#@-*/ /** * Validates if a tag has a legal value according to the Exif spec * * @param string $section Section where tag is located. * @param string $tag The tag to check. * @param mixed $val The value of the tag. * @param bool $recursive True if called recursively for array types. * @return bool */ private function validate( $section, $tag, $val, $recursive = false ) { $debug = "tag is '$tag'"; $etype = $this->mExifTags[$section][$tag]; $ecount = 1; if ( is_array( $etype ) ) { list( $etype, $ecount ) = $etype; if ( $recursive ) { $ecount = 1; // checking individual elements } } $count = count( $val ); if ( $ecount != $count ) { $this->debug( $val, __FUNCTION__, "Expected $ecount elements for $tag but got $count" ); return false; } if ( $count > 1 ) { foreach ( $val as $v ) { if ( !$this->validate( $section, $tag, $v, true ) ) { return false; } } return true; } // Does not work if not typecast switch ( (string)$etype ) { case (string)Exif::BYTE: $this->debug( $val, __FUNCTION__, $debug ); return $this->isByte( $val ); case (string)Exif::ASCII: $this->debug( $val, __FUNCTION__, $debug ); return $this->isASCII( $val ); case (string)Exif::SHORT: $this->debug( $val, __FUNCTION__, $debug ); return $this->isShort( $val ); case (string)Exif::LONG: $this->debug( $val, __FUNCTION__, $debug ); return $this->isLong( $val ); case (string)Exif::RATIONAL: $this->debug( $val, __FUNCTION__, $debug ); return $this->isRational( $val ); case (string)Exif::SHORT_OR_LONG: $this->debug( $val, __FUNCTION__, $debug ); return $this->isShort( $val ) || $this->isLong( $val ); case (string)Exif::UNDEFINED: $this->debug( $val, __FUNCTION__, $debug ); return $this->isUndefined( $val ); case (string)Exif::SLONG: $this->debug( $val, __FUNCTION__, $debug ); return $this->isSlong( $val ); case (string)Exif::SRATIONAL: $this->debug( $val, __FUNCTION__, $debug ); return $this->isSrational( $val ); case (string)Exif::IGNORE: $this->debug( $val, __FUNCTION__, $debug ); return false; default: $this->debug( $val, __FUNCTION__, "The tag '$tag' is unknown" ); return false; } } /** * Convenience function for debugging output * * @param mixed $in Arrays will be processed with print_r(). * @param string $fname Function name to log. * @param string|bool|null $action Default null. */ private function debug( $in, $fname, $action = null ) { if ( !$this->log ) { return; } $type = gettype( $in ); $class = ucfirst( __CLASS__ ); if ( is_array( $in ) ) { $in = print_r( $in, true ); } if ( $action === true ) { wfDebugLog( $this->log, "$class::$fname: accepted: '$in' (type: $type)" ); } elseif ( $action === false ) { wfDebugLog( $this->log, "$class::$fname: rejected: '$in' (type: $type)" ); } elseif ( $action === null ) { wfDebugLog( $this->log, "$class::$fname: input was: '$in' (type: $type)" ); } else { wfDebugLog( $this->log, "$class::$fname: $action (type: $type; content: '$in')" ); } } /** * Convenience function for debugging output * * @param string $fname The name of the function calling this function * @param bool $io Specify whether we're beginning or ending */ private function debugFile( $fname, $io ) { if ( !$this->log ) { return; } $class = ucfirst( __CLASS__ ); if ( $io ) { wfDebugLog( $this->log, "$class::$fname: begin processing: '{$this->basename}'" ); } else { wfDebugLog( $this->log, "$class::$fname: end processing: '{$this->basename}'" ); } } }