diff --git a/libavcodec/proresdec2.c b/libavcodec/proresdec2.c
index a57cece99b..fe1f3a28bd 100644
--- a/libavcodec/proresdec2.c
+++ b/libavcodec/proresdec2.c
@@ -831,4 +831,5 @@ const AVCodec ff_prores_decoder = {
     .decode         = decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_SLICE_THREADS | AV_CODEC_CAP_FRAME_THREADS,
     .profiles       = NULL_IF_CONFIG_SMALL(ff_prores_profiles),
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };