diff --git a/deck_original_v2.go b/deck_original_v2.go
index c9e5854..16071be 100644
--- a/deck_original_v2.go
+++ b/deck_original_v2.go
@@ -81,7 +81,7 @@ func (d *deckConfigOriginalV2) FillImage(keyIdx int, img image.Image) error {
 		}
 
 		var last uint8
-		if n < deckOriginalV2MaxPacketSize-deckOriginalV2HeaderSize {
+		if n < deckOriginalV2MaxPacketSize-deckOriginalV2HeaderSize || buf.Len() == 0 {
 			last = 1
 		}
 
diff --git a/deck_xl.go b/deck_xl.go
index 49e28d7..9f72f42 100644
--- a/deck_xl.go
+++ b/deck_xl.go
@@ -81,7 +81,7 @@ func (d *deckConfigXL) FillImage(keyIdx int, img image.Image) error {
 		}
 
 		var last uint8
-		if n < deckXLMaxPacketSize-deckXLHeaderSize {
+		if n < deckXLMaxPacketSize-deckXLHeaderSize || buf.Len() == 0 {
 			last = 1
 		}