Index: wp-includes/media.php
===================================================================
--- media.php	(revision 20352)
+++ media.php	(working copy)
@@ -101,7 +101,7 @@
 		$out .= 'width="'.intval($width).'" ';
 	if ($height)
 		$out .= 'height="'.intval($height).'" ';
-	return $out;
+	return apply_filters( 'image_hwstring', $out );
 }
 
 /**
@@ -1158,7 +1158,7 @@
 			return '';
 
 		$rawattr = $attr;
-		$attr = wp_parse_args( $attr, wp_embed_defaults() );
+		$attr = wp_parse_args( $attr, wp_embed_defaults( $url ) );
 
 		// kses converts & into & and we need to undo this
 		// See http://core.trac.wordpress.org/ticket/11311
@@ -1323,7 +1323,7 @@
  *
  * @return array Default embed parameters.
  */
-function wp_embed_defaults() {
+function wp_embed_defaults( $url = '' ) {
 	if ( !empty($GLOBALS['content_width']) )
 		$theme_width = (int) $GLOBALS['content_width'];
 
@@ -1343,7 +1343,7 @@
 	return apply_filters( 'embed_defaults', array(
 		'width'  => $width,
 		'height' => $height,
-	) );
+	) , $url );
 }
 
 /**