diff --git a/libavcodec/dnxhddec.c b/libavcodec/dnxhddec.c
index f67763ef47..383e64ca9e 100644
--- a/libavcodec/dnxhddec.c
+++ b/libavcodec/dnxhddec.c
@@ -145,6 +145,7 @@ static av_cold int dnxhd_decode_init_thread_copy(AVCodecContext *avctx)
 {
     DNXHDContext *ctx = avctx->priv_data;
 
+    ctx->avctx = avctx;
     // make sure VLC tables will be loaded when cid is parsed
     ctx->cid = -1;