includes/media/IPTC.php
<?php
/**
* Class for some IPTC functions.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup Media
*/
use Wikimedia\AtEase\AtEase;
/**
* Class for some IPTC functions.
*
* @ingroup Media
*/
class IPTC {
/**
* This takes the results of iptcparse() and puts it into a
* form that can be handled by mediawiki. Generally called from
* BitmapMetadataHandler::doApp13.
*
* @see http://www.iptc.org/std/IIM/4.1/specification/IIMV4.1.pdf
*
* @param string $rawData The app13 block from jpeg containing iptc/iim data
* @return array IPTC metadata array
*/
public static function parse( $rawData ) {
$parsed = iptcparse( $rawData );
$data = [];
if ( !is_array( $parsed ) ) {
return $data;
}
$c = '';
// charset info contained in tag 1:90.
if ( isset( $parsed['1#090'] ) && isset( $parsed['1#090'][0] ) ) {
$c = self::getCharset( $parsed['1#090'][0] );
if ( $c === false ) {
// Unknown charset. refuse to parse.
// note: There is a different between
// unknown and no charset specified.
return [];
}
unset( $parsed['1#090'] );
}
foreach ( $parsed as $tag => $val ) {
if ( isset( $val[0] ) && trim( $val[0] ) == '' ) {
wfDebugLog( 'iptc', "IPTC tag $tag had only whitespace as its value." );
continue;
}
switch ( $tag ) {
case '2#120': /*IPTC caption. mapped with exif ImageDescription*/
$data['ImageDescription'] = self::convIPTC( $val, $c );
break;
case '2#116': /* copyright. Mapped with exif copyright */
$data['Copyright'] = self::convIPTC( $val, $c );
break;
case '2#080': /* byline. Mapped with exif Artist */
/* merge with byline title (2:85)
* like how exif does it with
* Title, person. Not sure if this is best
* approach since we no longer have the two fields
* separate. each byline title entry corresponds to a
* specific byline. */
$bylines = self::convIPTC( $val, $c );
if ( isset( $parsed['2#085'] ) ) {
$titles = self::convIPTC( $parsed['2#085'], $c );
} else {
$titles = [];
}
$titleCount = count( $titles );
for ( $i = 0; $i < $titleCount; $i++ ) {
if ( isset( $bylines[$i] ) ) {
// theoretically this should always be set
// but doesn't hurt to be careful.
$bylines[$i] = $titles[$i] . ', ' . $bylines[$i];
}
}
$data['Artist'] = $bylines;
break;
case '2#025': /* keywords */
$data['Keywords'] = self::convIPTC( $val, $c );
break;
case '2#101': /* Country (shown) */
$data['CountryDest'] = self::convIPTC( $val, $c );
break;
case '2#095': /* state/province (shown) */
$data['ProvinceOrStateDest'] = self::convIPTC( $val, $c );
break;
case '2#090': /* city (Shown) */
$data['CityDest'] = self::convIPTC( $val, $c );
break;
case '2#092': /* sublocation (shown) */
$data['SublocationDest'] = self::convIPTC( $val, $c );
break;
case '2#005': /* object name/title */
$data['ObjectName'] = self::convIPTC( $val, $c );
break;
case '2#040': /* special instructions */
$data['SpecialInstructions'] = self::convIPTC( $val, $c );
break;
case '2#105': /* headline */
$data['Headline'] = self::convIPTC( $val, $c );
break;
case '2#110': /* credit */
/*"Identifies the provider of the objectdata,
* not necessarily the owner/creator". */
$data['Credit'] = self::convIPTC( $val, $c );
break;
case '2#115': /* source */
/* "Identifies the original owner of the intellectual content of the
*objectdata. This could be an agency, a member of an agency or
*an individual." */
$data['Source'] = self::convIPTC( $val, $c );
break;
case '2#007': /* edit status (lead, correction, etc) */
$data['EditStatus'] = self::convIPTC( $val, $c );
break;
case '2#015': /* category. deprecated. max 3 letters in theory, often more */
$data['iimCategory'] = self::convIPTC( $val, $c );
break;
case '2#020': /* category. deprecated. */
$data['iimSupplementalCategory'] = self::convIPTC( $val, $c );
break;
case '2#010': /*urgency (1-8. 1 most, 5 normal, 8 low priority)*/
$data['Urgency'] = self::convIPTC( $val, $c );
break;
case '2#022':
/* "Identifies objectdata that recurs often and predictably...
* Example: Euroweather" */
$data['FixtureIdentifier'] = self::convIPTC( $val, $c );
break;
case '2#026':
/* Content location code (iso 3166 + some custom things)
* ex: TUR (for turkey), XUN (for UN), XSP (outer space)
* See wikipedia article on iso 3166 and appendix D of iim std. */
$data['LocationDestCode'] = self::convIPTC( $val, $c );
break;
case '2#027':
/* Content location name. Full printable name
* of location of photo. */
$data['LocationDest'] = self::convIPTC( $val, $c );
break;
case '2#065':
/* Originating Program.
* Combine with Program version (2:70) if present.
*/
$software = self::convIPTC( $val, $c );
if ( count( $software ) !== 1 ) {
// according to iim standard this cannot have multiple values
// so if there is more than one, something weird is happening,
// and we skip it.
wfDebugLog( 'iptc', 'IPTC: Wrong count on 2:65 Software field' );
break;
}
if ( isset( $parsed['2#070'] ) ) {
// if a version is set for the software.
$softwareVersion = self::convIPTC( $parsed['2#070'], $c );
unset( $parsed['2#070'] );
$data['Software'] = [ [ $software[0], $softwareVersion[0] ] ];
} else {
$data['Software'] = $software;
}
break;
case '2#075':
/* Object cycle.
* a for morning (am), p for evening, b for both */
$data['ObjectCycle'] = self::convIPTC( $val, $c );
break;
case '2#100':
/* Country/Primary location code.
* "Indicates the code of the country/primary location where the
* intellectual property of the objectdata was created"
* unclear how this differs from 2#026
*/
$data['CountryCodeDest'] = self::convIPTC( $val, $c );
break;
case '2#103':
/* original transmission ref.
* "A code representing the location of original transmission ac-
* cording to practises of the provider."
*/
$data['OriginalTransmissionRef'] = self::convIPTC( $val, $c );
break;
case '2#118': /*contact*/
$data['Contact'] = self::convIPTC( $val, $c );
break;
case '2#122':
/* Writer/Editor
* "Identification of the name of the person involved in the writing,
* editing or correcting the objectdata or caption/abstract."
*/
$data['Writer'] = self::convIPTC( $val, $c );
break;
case '2#135': /* lang code */
$data['LanguageCode'] = self::convIPTC( $val, $c );
break;
// Start date stuff.
// It doesn't accept incomplete dates even though they are valid
// according to spec.
// Should potentially store timezone as well.
case '2#055':
// Date created (not date digitized).
// Maps to exif DateTimeOriginal
$time = $parsed['2#060'] ?? [];
$timestamp = self::timeHelper( $val, $time, $c );
if ( $timestamp ) {
$data['DateTimeOriginal'] = $timestamp;
}
break;
case '2#062':
// Date converted to digital representation.
// Maps to exif DateTimeDigitized
$time = $parsed['2#063'] ?? [];
$timestamp = self::timeHelper( $val, $time, $c );
if ( $timestamp ) {
$data['DateTimeDigitized'] = $timestamp;
}
break;
case '2#030':
// Date released.
$time = $parsed['2#035'] ?? [];
$timestamp = self::timeHelper( $val, $time, $c );
if ( $timestamp ) {
$data['DateTimeReleased'] = $timestamp;
}
break;
case '2#037':
// Date expires.
$time = $parsed['2#038'] ?? [];
$timestamp = self::timeHelper( $val, $time, $c );
if ( $timestamp ) {
$data['DateTimeExpires'] = $timestamp;
}
break;
case '2#000': /* iim version */
// unlike other tags, this is a 2-byte binary number.
// technically this is required if there is iptc data
// but in practise it isn't always there.
if ( strlen( $val[0] ) === 2 ) {
// if is just to be paranoid.
$versionValue = ord( substr( $val[0], 0, 1 ) ) * 256;
$versionValue += ord( substr( $val[0], 1, 1 ) );
$data['iimVersion'] = $versionValue;
}
break;
case '2#004':
// IntellectualGenere.
// first 4 characters are an id code
// That we're not really interested in.
// This prop is weird, since it's
// allowed to have multiple values
// in iim 4.1, but not in the XMP
// stuff. We're going to just
// extract the first value.
$con = self::convIPTC( $val, $c );
if ( strlen( $con[0] ) < 5 ) {
wfDebugLog( 'iptc', 'IPTC: '
. '2:04 too short. '
. 'Ignoring.' );
break;
}
$extracted = substr( $con[0], 4 );
$data['IntellectualGenre'] = $extracted;
break;
case '2#012':
// Subject News code - this is a compound field
// at the moment we only extract the subject news
// code, which is an 8 digit (ascii) number
// describing the subject matter of the content.
$codes = self::convIPTC( $val, $c );
foreach ( $codes as $ic ) {
$fields = explode( ':', $ic, 3 );
if ( count( $fields ) < 2 || $fields[0] !== 'IPTC' ) {
wfDebugLog( 'IPTC', 'IPTC: '
. 'Invalid 2:12 - ' . $ic );
break;
}
$data['SubjectNewsCode'] = $fields[1];
}
break;
// purposely does not do 2:125, 2:130, 2:131,
// 2:47, 2:50, 2:45, 2:42, 2:8, 2:3
// 2:200, 2:201, 2:202
// or the audio stuff (2:150 to 2:154)
case '2#070':
case '2#060':
case '2#063':
case '2#085':
case '2#038':
case '2#035':
// ignore. Handled elsewhere.
break;
default:
wfDebugLog( 'iptc', "Unsupported iptc tag: $tag. Value: " . implode( ',', $val ) );
break;
}
}
return $data;
}
/**
* Convert an iptc date and time tags into the exif format
*
* @todo Potentially this should also capture the timezone offset.
* @param array $date The date tag
* @param array $time The time tag
* @param string $charset
* @return string|null Date in EXIF format.
*/
private static function timeHelper( $date, $time, $charset ) {
if ( count( $date ) === 1 ) {
// the standard says this should always be 1
// just double checking.
[ $date ] = self::convIPTC( $date, $charset );
} else {
return null;
}
if ( count( $time ) === 1 ) {
[ $time ] = self::convIPTC( $time, $charset );
$dateOnly = false;
} else {
$time = '000000+0000'; // placeholder
$dateOnly = true;
}
if ( !( preg_match( '/\d\d\d\d\d\d[-+]\d\d\d\d/', $time )
&& preg_match( '/\d\d\d\d\d\d\d\d/', $date )
&& substr( $date, 0, 4 ) !== '0000'
&& substr( $date, 4, 2 ) !== '00'
&& substr( $date, 6, 2 ) !== '00'
) ) {
// something wrong.
// Note, this rejects some valid dates according to iptc spec
// for example: the date 00000400 means the photo was taken in
// April, but the year and day is unknown. We don't process these
// types of incomplete dates atm.
wfDebugLog( 'iptc', "IPTC: invalid time ( $time ) or date ( $date )" );
return null;
}
$unixTS = wfTimestamp( TS_UNIX, $date . substr( $time, 0, 6 ) );
if ( $unixTS === false ) {
wfDebugLog( 'iptc', "IPTC: can't convert date to TS_UNIX: $date $time." );
return null;
}
$tz = ( (int)substr( $time, 7, 2 ) * 60 * 60 )
+ ( (int)substr( $time, 9, 2 ) * 60 );
if ( substr( $time, 6, 1 ) === '-' ) {
$tz = -$tz;
}
$finalTimestamp = wfTimestamp( TS_EXIF, (int)$unixTS + $tz );
if ( $finalTimestamp === false ) {
wfDebugLog( 'iptc', "IPTC: can't make final timestamp. Date: " . ( (int)$unixTS + $tz ) );
return null;
}
if ( $dateOnly ) {
// return the date only
return substr( $finalTimestamp, 0, 10 );
}
return $finalTimestamp;
}
/**
* Helper function to convert charset for iptc values.
* @param string|array $data The iptc string
* @param string $charset
*
* @return string|array
*/
private static function convIPTC( $data, $charset ) {
if ( is_array( $data ) ) {
foreach ( $data as &$val ) {
$val = self::convIPTCHelper( $val, $charset );
}
} else {
$data = self::convIPTCHelper( $data, $charset );
}
return $data;
}
/**
* Helper function of a helper function to convert charset for iptc values.
* @param string|array $data The IPTC string
* @param string $charset
*
* @return string
*/
private static function convIPTCHelper( $data, $charset ) {
if ( $charset ) {
AtEase::suppressWarnings();
$data = iconv( $charset, "UTF-8//IGNORE", $data );
AtEase::restoreWarnings();
if ( $data === false ) {
$data = "";
wfDebugLog( 'iptc', __METHOD__ . " Error converting iptc data charset $charset to utf-8" );
}
} else {
// treat as utf-8 if is valid utf-8. otherwise pretend its windows-1252
// most of the time if there is no 1:90 tag, it is either ascii, latin1, or utf-8
$oldData = $data;
UtfNormal\Validator::quickIsNFCVerify( $data ); // make $data valid utf-8
if ( $data === $oldData ) {
return $data; // if validation didn't change $data
}
return self::convIPTCHelper( $oldData, 'Windows-1252' );
}
return trim( $data );
}
/**
* take the value of 1:90 tag and returns a charset
* @param string $tag 1:90 tag.
* @return string Charset name or "?"
* Warning, this function does not (and is not intended to) detect
* all iso 2022 escape codes. In practise, the code for utf-8 is the
* only code that seems to have wide use. It does detect that code.
*/
public static function getCharset( $tag ) {
// According to iim standard, charset is defined by the tag 1:90.
// in which there are iso 2022 escape sequences to specify the character set.
// the iim standard seems to encourage that all necessary escape sequences are
// in the 1:90 tag, but says it doesn't have to be.
// This is in need of more testing probably. This is definitely not complete.
// however reading the docs of some other iptc software, it appears that most iptc software
// only recognizes utf-8. If 1:90 tag is not present content is
// usually ascii or iso-8859-1 (and sometimes utf-8), but no guarantee.
// This also won't work if there are more than one escape sequence in the 1:90 tag
// or if something is put in the G2, or G3 charsets, etc. It will only reliably recognize utf-8.
// This is just going through the charsets mentioned in appendix C of the iim standard.
// \x1b = ESC.
switch ( $tag ) {
case "\x1b%G": // utf-8
// Also call things that are compatible with utf-8, utf-8 (e.g. ascii)
case "\x1b(B": // ascii
case "\x1b(@": // iso-646-IRV (ascii in latest version, $ different in older version)
$c = 'UTF-8';
break;
case "\x1b(A": // like ascii, but british.
$c = 'ISO646-GB';
break;
case "\x1b(C": // some obscure sweedish/finland encoding
$c = 'ISO-IR-8-1';
break;
case "\x1b(D":
$c = 'ISO-IR-8-2';
break;
case "\x1b(E": // some obscure danish/norway encoding
$c = 'ISO-IR-9-1';
break;
case "\x1b(F":
$c = 'ISO-IR-9-2';
break;
case "\x1b(G":
$c = 'SEN_850200_B'; // aka iso 646-SE; ascii-like
break;
case "\x1b(I":
$c = "ISO646-IT";
break;
case "\x1b(L":
$c = "ISO646-PT";
break;
case "\x1b(Z":
$c = "ISO646-ES";
break;
case "\x1b([":
$c = "GREEK7-OLD";
break;
case "\x1b(K":
$c = "ISO646-DE";
break;
case "\x1b(N": // crylic
$c = "ISO_5427";
break;
case "\x1b(`": // iso646-NO
$c = "NS_4551-1";
break;
case "\x1b(f": // iso646-FR
$c = "NF_Z_62-010";
break;
case "\x1b(g":
$c = "PT2"; // iso646-PT2
break;
case "\x1b(h":
$c = "ES2";
break;
case "\x1b(i": // iso646-HU
$c = "MSZ_7795.3";
break;
case "\x1b(w":
$c = "CSA_Z243.4-1985-1";
break;
case "\x1b(x":
$c = "CSA_Z243.4-1985-2";
break;
case "\x1b\$(B":
case "\x1b\$B":
case "\x1b&@\x1b\$B":
case "\x1b&@\x1b\$(B":
$c = "JIS_C6226-1983";
break;
case "\x1b-A": // iso-8859-1. at least for the high code characters.
case "\x1b(@\x1b-A":
case "\x1b(B\x1b-A":
$c = 'ISO-8859-1';
break;
case "\x1b-B": // iso-8859-2. at least for the high code characters.
$c = 'ISO-8859-2';
break;
case "\x1b-C": // iso-8859-3. at least for the high code characters.
$c = 'ISO-8859-3';
break;
case "\x1b-D": // iso-8859-4. at least for the high code characters.
$c = 'ISO-8859-4';
break;
case "\x1b-E": // iso-8859-5. at least for the high code characters.
$c = 'ISO-8859-5';
break;
case "\x1b-F": // iso-8859-6. at least for the high code characters.
$c = 'ISO-8859-6';
break;
case "\x1b-G": // iso-8859-7. at least for the high code characters.
$c = 'ISO-8859-7';
break;
case "\x1b-H": // iso-8859-8. at least for the high code characters.
$c = 'ISO-8859-8';
break;
case "\x1b-I": // CSN_369103. at least for the high code characters.
$c = 'CSN_369103';
break;
default:
wfDebugLog( 'iptc', __METHOD__ . ': Unknown charset in iptc 1:90: ' . bin2hex( $tag ) );
// at this point just give up and refuse to parse iptc?
$c = false;
}
return $c;
}
}