diff --git wp-admin/includes/image-edit.php wp-admin/includes/image-edit.php
index f390b5e..0b06926 100644
--- wp-includes/class-wp-image-editor-gd.php
+++ wp-includes/class-wp-image-editor-gd.php
@@ -32,7 +32,7 @@ class WP_Image_Editor_GD extends WP_Image_Editor {
 	 *
 	 * @return boolean
 	 */
-	public static function test() {
+	public function test() {
 		if ( ! extension_loaded('gd') || ! function_exists('gd_info') )
 			return false;
 
@@ -99,7 +99,7 @@ class WP_Image_Editor_GD extends WP_Image_Editor {
 	 * @param string $mime_type
 	 * @return boolean
 	 */
-	public static function supports_mime_type( $mime_type ) {
+	public function supports_mime_type( $mime_type ) {
 		$allowed_mime_types = array( 'image/gif', 'image/png', 'image/jpeg' );
 
 		return in_array( $mime_type, $allowed_mime_types );
diff --git wp-includes/class-wp-image-editor-imagick.php wp-includes/class-wp-image-editor-imagick.php
index 3e35775..7954206 100644
--- wp-includes/class-wp-image-editor-imagick.php
+++ wp-includes/class-wp-image-editor-imagick.php
@@ -33,7 +33,7 @@ class WP_Image_Editor_Imagick extends WP_Image_Editor {
 	 *
 	 * @return boolean
 	 */
-	public static function test() {
+	public function test() {
 		if ( ! extension_loaded( 'imagick' ) )
 			return false;
 
@@ -143,7 +143,7 @@ class WP_Image_Editor_Imagick extends WP_Image_Editor {
 	 * @param string $mime_type
 	 * @return boolean
 	 */
-	public static function supports_mime_type( $mime_type ) {
+	public function supports_mime_type( $mime_type ) {
 		if ( ! $mime_type )
 			return false;
 
diff --git wp-includes/class-wp-image-editor.php wp-includes/class-wp-image-editor.php
index 27df919..83c6b94 100644
--- wp-includes/class-wp-image-editor.php
+++ wp-includes/class-wp-image-editor.php
@@ -76,9 +76,9 @@ abstract class WP_Image_Editor {
 		return self::$implementation;
 	}
 
-	abstract public static function test(); // returns bool
+	abstract public function test(); // returns bool
 	abstract protected function load(); // returns bool|WP_Error
-	abstract public static function supports_mime_type( $mime_type ); // returns bool
+	abstract public function supports_mime_type( $mime_type ); // returns bool
 	abstract public function resize( $max_w, $max_h, $crop = false );
 	abstract public function multi_resize( $sizes );
 	abstract public function crop( $src_x, $src_y, $src_w, $src_h, $dst_w = null, $dst_h = null, $src_abs = false );