diff --git src/wp-includes/media.php src/wp-includes/media.php
index 01543b9dcd..62ec9615d7 100644
--- src/wp-includes/media.php
+++ src/wp-includes/media.php
@@ -3751,6 +3751,12 @@ function wp_get_image_editor( $path, $args = array() ) {
 		}
 	}
 
+	/** This filter is documented in wp-includes/class-wp-image-editor.php */
+	$output_format = apply_filters( 'image_editor_output_format', array(), $path, $args['mime_type'] );
+	if ( isset( $output_format[ $args['mime_type'] ] ) ) {
+		$args['mime_type'] = $output_format[ $mime_type ];
+	}
+
 	$implementation = _wp_image_editor_choose( $args );
 
 	if ( $implementation ) {