diff --git a/libavcodec/h2645_parse.c b/libavcodec/h2645_parse.c
index a36ef4f5a0..6fbe97ad4a 100644
--- a/libavcodec/h2645_parse.c
+++ b/libavcodec/h2645_parse.c
@@ -467,7 +467,7 @@ int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length,
             memset(pkt->nals + pkt->nals_allocated, 0, sizeof(*pkt->nals));
 
             nal = &pkt->nals[pkt->nb_nals];
-            nal->skipped_bytes_pos_size = 1024; // initial buffer size
+            nal->skipped_bytes_pos_size = FFMIN(1024, extract_length/3+1); // initial buffer size
             nal->skipped_bytes_pos = av_malloc_array(nal->skipped_bytes_pos_size, sizeof(*nal->skipped_bytes_pos));
             if (!nal->skipped_bytes_pos)
                 return AVERROR(ENOMEM);