Jpeg.php

Go to the documentation of this file.

<?php
class JpegHandler extends ExifBitmapHandler {
    const SRGB_EXIF_COLOR_SPACE = 'sRGB';
    const SRGB_ICC_PROFILE_DESCRIPTION = 'sRGB IEC61966-2.1';
 
    function normaliseParams( $image, &$params ) {
        if ( !parent::normaliseParams( $image, $params ) ) {
            return false;
        }
        if ( isset( $params['quality'] ) && !self::validateQuality( $params['quality'] ) ) {
            return false;
        }
        return true;
    }
 
    public function validateParam( $name, $value ) {
        if ( $name === 'quality' ) {
            return self::validateQuality( $value );
        } else {
            return parent::validateParam( $name, $value );
        }
    }
 
    private static function validateQuality( $value ) {
        return $value === 'low';
    }
 
    public function makeParamString( $params ) {
        // Prepend quality as "qValue-". This has to match parseParamString() below
        $res = parent::makeParamString( $params );
        if ( $res && isset( $params['quality'] ) ) {
            $res = "q{$params['quality']}-$res";
        }
        return $res;
    }
 
    public function parseParamString( $str ) {
        // $str contains "qlow-200px" or "200px" strings because thumb.php would strip the filename
        // first - check if the string begins with "qlow-", and if so, treat it as quality.
        // Pass the first portion, or the whole string if "qlow-" not found, to the parent
        // The parsing must match the makeParamString() above
        $res = false;
        $m = false;
        if ( preg_match( '/q([^-]+)-(.*)$/', $str, $m ) ) {
            $v = $m[1];
            if ( self::validateQuality( $v ) ) {
                $res = parent::parseParamString( $m[2] );
                if ( $res ) {
                    $res['quality'] = $v;
                }
            }
        } else {
            $res = parent::parseParamString( $str );
        }
        return $res;
    }
 
    function getScriptParams( $params ) {
        $res = parent::getScriptParams( $params );
        if ( isset( $params['quality'] ) ) {
            $res['quality'] = $params['quality'];
        }
        return $res;
    }
 
    function getMetadata( $image, $filename ) {
        try {
            $meta = BitmapMetadataHandler::Jpeg( $filename );
            if ( !is_array( $meta ) ) {
                // This should never happen, but doesn't hurt to be paranoid.
                throw new MWException( 'Metadata array is not an array' );
            }
            $meta['MEDIAWIKI_EXIF_VERSION'] = Exif::version();
 
            return serialize( $meta );
        } catch ( Exception $e ) {
            // BitmapMetadataHandler throws an exception in certain exceptional
            // cases like if file does not exist.
            wfDebug( __METHOD__ . ': ' . $e->getMessage() . "\n" );
 
            /* This used to use 0 (ExifBitmapHandler::OLD_BROKEN_FILE) for the cases
             *   * No metadata in the file
             *   * Something is broken in the file.
             * However, if the metadata support gets expanded then you can't tell if the 0 is from
             * a broken file, or just no props found. A broken file is likely to stay broken, but
             * a file which had no props could have props once the metadata support is improved.
             * Thus switch to using -1 to denote only a broken file, and use an array with only
             * MEDIAWIKI_EXIF_VERSION to denote no props.
             */
 
            return ExifBitmapHandler::BROKEN_FILE;
        }
    }
 
    public function rotate( $file, $params ) {
        global $wgJpegTran;
 
        $rotation = ( $params['rotation'] + $this->getRotation( $file ) ) % 360;
 
        if ( $wgJpegTran && is_executable( $wgJpegTran ) ) {
            $cmd = wfEscapeShellArg( $wgJpegTran ) .
                " -rotate " . wfEscapeShellArg( $rotation ) .
                " -outfile " . wfEscapeShellArg( $params['dstPath'] ) .
                " " . wfEscapeShellArg( $params['srcPath'] );
            wfDebug( __METHOD__ . ": running jpgtran: $cmd\n" );
            $retval = 0;
            $err = wfShellExecWithStderr( $cmd, $retval );
            if ( $retval !== 0 ) {
                $this->logErrorForExternalProcess( $retval, $err, $cmd );
 
                return new MediaTransformError( 'thumbnail_error', 0, 0, $err );
            }
 
            return false;
        } else {
            return parent::rotate( $file, $params );
        }
    }
 
    public function supportsBucketing() {
        return true;
    }
 
    public function sanitizeParamsForBucketing( $params ) {
        $params = parent::sanitizeParamsForBucketing( $params );
 
        // Quality needs to be cleared for bucketing. Buckets need to be default quality
        if ( isset( $params['quality'] ) ) {
            unset( $params['quality'] );
        }
 
        return $params;
    }
 
    protected function transformImageMagick( $image, $params ) {
        global $wgUseTinyRGBForJPGThumbnails;
 
        $ret = parent::transformImageMagick( $image, $params );
 
        if ( $ret ) {
            return $ret;
        }
 
        if ( $wgUseTinyRGBForJPGThumbnails ) {
            // T100976 If the profile embedded in the JPG is sRGB, swap it for the smaller
            // (and free) TinyRGB
 
            $colorSpaces = [ self::SRGB_EXIF_COLOR_SPACE, '-' ];
            $profiles = [ self::SRGB_ICC_PROFILE_DESCRIPTION ];
 
            // we'll also add TinyRGB profile to images lacking a profile, but
            // only if they're not low quality (which are meant to save bandwith
            // and we don't want to increase the filesize by adding a profile)
            if ( isset( $params['quality'] ) && $params['quality'] > 30 ) {
                $profiles[] = '-';
            }
 
            $this->swapICCProfile(
                $params['dstPath'],
                $colorSpaces,
                $profiles,
                realpath( __DIR__ ) . '/tinyrgb.icc'
            );
        }
 
        return false;
    }
 
    public function swapICCProfile( $filepath, array $colorSpaces,
                                    array $oldProfileStrings, $profileFilepath
    ) {
        global $wgExiftool;
 
        if ( !$wgExiftool || !is_executable( $wgExiftool ) ) {
            return false;
        }
 
        $cmd = wfEscapeShellArg( $wgExiftool,
            '-EXIF:ColorSpace',
            '-ICC_Profile:ProfileDescription',
            '-S',
            '-T',
            $filepath
        );
 
        $output = wfShellExecWithStderr( $cmd, $retval );
 
        // Explode EXIF data into an array with [0 => Color Space, 1 => Device Model Desc]
        $data = explode( "\t", trim( $output ) );
 
        if ( $retval !== 0 ) {
            return false;
        }
 
        // Make a regex out of the source data to match it to an array of color
        // spaces in a case-insensitive way
        $colorSpaceRegex = '/'.preg_quote( $data[0], '/' ).'/i';
        if ( empty( preg_grep( $colorSpaceRegex, $colorSpaces ) ) ) {
            // We can't establish that this file matches the color space, don't process it
            return false;
        }
 
        $profileRegex = '/'.preg_quote( $data[1], '/' ).'/i';
        if ( empty( preg_grep( $profileRegex, $oldProfileStrings ) ) ) {
            // We can't establish that this file has the expected ICC profile, don't process it
            return false;
        }
 
        $cmd = wfEscapeShellArg( $wgExiftool,
            '-overwrite_original',
            '-icc_profile<=' . $profileFilepath,
            $filepath
        );
 
        $output = wfShellExecWithStderr( $cmd, $retval );
 
        if ( $retval !== 0 ) {
            $this->logErrorForExternalProcess( $retval, $output, $cmd );
 
            return false;
        }
 
        return true;
    }
}