diff --git a/src/Intervention/Image/AbstractEncoder.php b/src/Intervention/Image/AbstractEncoder.php
index c25f8bffd..6239756c4 100644
--- a/src/Intervention/Image/AbstractEncoder.php
+++ b/src/Intervention/Image/AbstractEncoder.php
@@ -157,6 +157,7 @@ public function process(Image $image, $format = null, $quality = null)
             case 'x-win-bitmap':
             case 'x-windows-bmp':
             case 'x-xbitmap':
+            case 'image/bmp':
             case 'image/ms-bmp':
             case 'image/x-bitmap':
             case 'image/x-bmp':