diff --git a/libavcodec/realtextdec.c b/libavcodec/realtextdec.c
index b09ff78ea4..5c41a5a00d 100644
--- a/libavcodec/realtextdec.c
+++ b/libavcodec/realtextdec.c
@@ -27,6 +27,7 @@
 #include "avcodec.h"
 #include "ass.h"
 #include "codec_internal.h"
+#include "decode.h"
 #include "libavutil/avstring.h"
 #include "libavutil/bprint.h"
 
@@ -60,10 +61,13 @@ static int realtext_decode_frame(AVCodecContext *avctx, AVSubtitle *sub,
                                  int *got_sub_ptr, const AVPacket *avpkt)
 {
     int ret = 0;
-    const char *ptr = avpkt->data;
+    const char *ptr = ff_decode_subtitle_text(avctx, avpkt);
     FFASSDecoderContext *s = avctx->priv_data;
     AVBPrint buf;
 
+    if (avpkt->size > 0 && !ptr)
+        return AVERROR(ENOMEM);
+
     av_bprint_init(&buf, 0, 4096);
     if (ptr && avpkt->size > 0 && !rt_event_to_ass(&buf, ptr))
         ret = ff_ass_add_rect(sub, buf.str, s->readorder++, 0, NULL, NULL);