diff --git a/libavformat/utils.c b/libavformat/utils.c
index d5ad4ec4b0..123d67800b 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -4062,7 +4062,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
 
             if (!st->r_frame_rate.num) {
                 if (    avctx->time_base.den * (int64_t) st->time_base.num
-                    <= avctx->time_base.num * avctx->ticks_per_frame * (int64_t) st->time_base.den) {
+                    <= avctx->time_base.num * avctx->ticks_per_frame * (uint64_t) st->time_base.den) {
                     av_reduce(&st->r_frame_rate.num, &st->r_frame_rate.den,
                               avctx->time_base.den, (int64_t)avctx->time_base.num * avctx->ticks_per_frame, INT_MAX);
                 } else {