Index: y4mdenoise/main.c
--- y4mdenoise/main.c.orig
+++ y4mdenoise/main.c
@@ -274,7 +274,7 @@ int main(int argc, char *argv[])
 void
 process_commandline(int argc, char *argv[])
 {
-  char c;
+  int c;
 
   while ((c = getopt (argc, argv, "h?z:Z:t:T:r:R:m:M:f:BI:p:v:")) != -1)
   {
