diff --git a/vp9/vp9_cx_iface.c b/vp9/vp9_cx_iface.c
index dc89b4e..bf8eec7 100644
--- a/vp9/vp9_cx_iface.c
+++ b/vp9/vp9_cx_iface.c
@@ -808,7 +808,7 @@
 }
 
 // vp9 uses 10,000,000 ticks/second as time stamp
-#define TICKS_PER_SEC 10000000
+#define TICKS_PER_SEC 10000000LL
 
 static int64_t timebase_units_to_ticks(const vpx_rational_t *timebase,
                                        int64_t n) {