Jpeg.php

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<?php
class JpegHandler extends ExifBitmapHandler {

    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;
    }
}