diff --git a/libavcodec/huffyuv.c b/libavcodec/huffyuv.c
index efa87de802..412fe4b68d 100644
--- a/libavcodec/huffyuv.c
+++ b/libavcodec/huffyuv.c
@@ -514,7 +514,7 @@ s->bgr32=1;
         }
         break;
     default:
-        assert(0);
+        return AVERROR_INVALIDDATA;
     }
 
     alloc_temp(s);