diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c
index 7a27258758..3d48bd76a5 100644
--- a/fftools/ffmpeg.c
+++ b/fftools/ffmpeg.c
@@ -32,6 +32,7 @@
 #include <limits.h>
 #include <stdatomic.h>
 #include <stdint.h>
+#include <locale.h>
 
 #if HAVE_IO_H
 #include <io.h>
@@ -4912,6 +4913,8 @@ static void log_callback_null(void *ptr, int level, const char *fmt, va_list vl)
 
 int main(int argc, char **argv)
 {
+       // init locale.
+       setlocale(LC_ALL, "");
     int i, ret;
     BenchmarkTimeStamps ti;