XCF.php

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<?php
class XCFHandler extends BitmapHandler {

    function mustRender( $file ) {
        return true;
    }

    function getThumbType( $ext, $mime, $params = null ) {
        return array( 'png', 'image/png' );
    }

    function getImageSize( $image, $filename ) {
        return self::getXCFMetaData( $filename );
    }

    static function getXCFMetaData( $filename ) {
        # Decode master structure
        $f = fopen( $filename, 'rb' );
        if ( !$f ) {
            return false;
        }
        # The image structure always starts at offset 0 in the XCF file.
        # So we just read it :-)
        $binaryHeader = fread( $f, 26 );
        fclose( $f );

        # Master image structure:
        #
        # byte[9] "gimp xcf "  File type magic
        # byte[4] version      XCF version
        #                        "file" - version 0
        #                        "v001" - version 1
        #                        "v002" - version 2
        # byte    0            Zero-terminator for version tag
        # uint32  width        With of canvas
        # uint32  height       Height of canvas
        # uint32  base_type    Color mode of the image; one of
        #                         0: RGB color
        #                         1: Grayscale
        #                         2: Indexed color
        #        (enum GimpImageBaseType in libgimpbase/gimpbaseenums.h)
        try {
            $header = wfUnpack(
                  "A9magic"     # A: space padded
                . "/a5version"  # a: zero padded
                . "/Nwidth"     # \
                . "/Nheight"    # N: unsigned long 32bit big endian
                . "/Nbase_type" # /
            , $binaryHeader
            );
        } catch ( MWException $mwe ) {
            return false;
        }

        # Check values
        if ( $header['magic'] !== 'gimp xcf' ) {
            wfDebug( __METHOD__ . " '$filename' has invalid magic signature.\n" );
            return false;
        }
        # TODO: we might want to check for sane values of width and height

        wfDebug( __METHOD__ . ": canvas size of '$filename' is {$header['width']} x {$header['height']} px\n" );

        # Forge a return array containing metadata information just like getimagesize()
        # See PHP documentation at: http://www.php.net/getimagesize
        $metadata = array();
        $metadata[0] = $header['width'];
        $metadata[1] = $header['height'];
        $metadata[2] = null;   # IMAGETYPE constant, none exist for XCF.
        $metadata[3] = sprintf(
            'height="%s" width="%s"', $header['height'], $header['width']
        );
        $metadata['mime'] = 'image/x-xcf';
        $metadata['channels'] = null;
        $metadata['bits'] = 8;  # Always 8-bits per color

        assert( '7 == count($metadata); # return array must contains 7 elements just like getimagesize() return' );

        return $metadata;
    }

    protected static function getScalerType( $dstPath, $checkDstPath = true ) {
        return "im";
    }
}