diff --git a/libavcodec/y41pdec.c b/libavcodec/y41pdec.c
index 85a39e4ae2..2bfabe277e 100644
--- a/libavcodec/y41pdec.c
+++ b/libavcodec/y41pdec.c
@@ -89,4 +89,5 @@ AVCodec ff_y41p_decoder = {
     .init         = y41p_decode_init,
     .decode       = y41p_decode_frame,
     .capabilities = AV_CODEC_CAP_DR1,
+    .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
 };