* First simple XCF thumbnailing. Convert from ImageMagick has buggy

support for XCF, though, so one of the solutions at
  http://stackoverflow.com/questions/5794640/how-to-convert-xcf-to-png-using-gimp-from-the-command-line
  is probably better.

* File::maybeDoTransform() since (at least) r106752 neglects what
  BitmapHandler::getThumbType() returns, so add support for that.

* Add $wgImageMagickIdentifyCommand to avoid writing a parser for XCF
  metadata.

includes/DefaultSettings.php

@@ -620,6 +620,7 @@ $wgMediaHandlers = array(
 	'image/tiff' => 'TiffHandler',
 	'image/x-ms-bmp' => 'BmpHandler',
 	'image/x-bmp' => 'BmpHandler',
+	'image/x-xcf' => 'XCFHandler',
 	'image/svg+xml' => 'SvgHandler', // official
 	'image/svg' => 'SvgHandler', // compat
 	'image/vnd.djvu' => 'DjVuHandler', // official
@@ -638,6 +639,8 @@ $wgMediaHandlers = array(
 $wgUseImageMagick		= false;
 /** The convert command shipped with ImageMagick */
 $wgImageMagickConvertCommand    = '/usr/bin/convert';
+/** The identify command shipped with ImageMagick */
+$wgImageMagickIdentifyCommand   = '/usr/bin/identify';
 
 /** Sharpening parameter to ImageMagick */
 $wgSharpenParameter = '0x0.4';

includes/filerepo/file/File.php

@@ -778,8 +778,11 @@ abstract class File {
 			wfDebug( __METHOD__ . " forcing rendering per flag File::RENDER_FORCE\n" );
 		}
 
-		// Create a temp FS file with the same extension
-		$tmpFile = TempFSFile::factory( 'transform_', $this->getExtension() );
+		// Create a temp FS file with the same extension and the thumbnail
+		$extension = $this->getExtension();
+		list( $thumbExt, $thumbMime ) = $this->handler->getThumbType(
+			$extension, $this->getMimeType(), $params );
+		$tmpFile = TempFSFile::factory( 'transform_', $this->getExtension() . '.' . $thumbExt );
 		if ( !$tmpFile ) {
 			return new MediaTransformError( 'thumbnail_error',
 				$params['width'], 0, wfMsg( 'thumbnail-temp-create' ) );

includes/media/Bitmap.php

@@ -302,6 +302,8 @@ class BitmapHandler extends ImageHandler {
 					$animation_post = '-fuzz 5% -layers optimizeTransparency';
 				}
 			}
+		} elseif ( $params['mimeType'] == 'image/x-xcf' ) {
+			$animation_post = '-layers merge';
 		}
 
 		// Use one thread only, to avoid deadlock bugs on OOM

includes/media/XCF.php

@@ -0,0 +1,93 @@
+<?php
+/**
+ * Handler for Microsoft's bitmap format
+ *
+ * @file
+ * @ingroup Media
+ */
+
+/**
+ * Handler for Microsoft's bitmap format; getimagesize() doesn't
+ * support these files
+ *
+ * @ingroup Media
+ */
+class XCFHandler extends BitmapHandler {
+
+	/**
+	 * Render files as PNG
+	 *
+	 * @param $ext
+	 * @param $mime
+	 * @param $params
+	 * @return array
+	 */
+	function getThumbType( $ext, $mime, $params = null ) {
+		return array( 'png', 'image/png' );
+	}
+
+	/**
+	 * Get width and height from the bmp header.
+	 *
+	 * @param $image
+	 * @param $filename
+	 * @return array
+	 */
+	function getImageSize( $image, $filename ) {
+		return self::getXCFMetaData( $filename );
+	}
+
+	static function getXCFMetaData( $filename ) {
+		global $wgImageMagickIdentifyCommand;
+
+		$md = false;
+		$cmd = wfEscapeShellArg( $wgImageMagickIdentifyCommand ) . ' -verbose ' . wfEscapeShellArg( $filename );
+		wfDebug( __METHOD__ . ": Running $cmd \n" );
+		$retval = '';
+		$return = wfShellExec( $cmd, $retval );
+
+		if( $retval == 0 ) {
+			$colorspace = preg_match_all( '/ *Colorspace: RGB/', $return, $match );
+			$frameCount = preg_match_all( '/ *Geometry: ([0-9]+x[0-9]+)\+[+0-9]*/', $return, $match );
+			wfDebug( __METHOD__ . ": Got $frameCount matches\n" );
+
+			/* if( $frameCount == 1 ) { */
+			/* 	preg_match( '/([0-9]+)x([0-9]+)/sm', $match[1][0], $m ); */
+			/* 	$sizeX = $m[1]; */
+			/* 	$sizeY = $m[2]; */
+			/* } else { */
+				$sizeX = 0;
+				$sizeY = 0;
+
+				foreach( $match[1] as $res ) {
+					preg_match( '/([0-9]+)x([0-9]+)/sm', $res, $m );
+					if( $m[1] > $sizeX ) {
+						$sizeX = $m[1];
+					}
+					if( $m[2] > $sizeY ) {
+						$sizeY = $m[2];
+					}
+				}
+			/* } */
+
+			wfDebug( __METHOD__ . ": Found $sizeX x $sizeY x $frameCount \n" );
+			$md['frameCount'] = $frameCount;
+			$md[0] = $sizeX;
+			$md[1] = $sizeY;
+			$md[2] = null;
+			$md[3] = "height=\"$sizeY\" width=\"$sizeX\"";
+			$md['mime'] = 'image/x-xcf';
+			$md['channels'] = $colorspace == 1 ? 3 : 4;
+		}
+		return $md;
+	}
+
+	/**
+	 * Must use "im" for XCF
+	 *
+	 * @return string
+	 */
+	protected static function getScalerType( $dstPath, $checkDstPath = true ) {
+		return "im";
+	}
+}