diff --git a/pixel.cpp b/pixel.cpp
index f90c9cfa576de4c46cb685da21cb6f8ce6de253e..e38620704cabb51125947d4c29acd265418685ae 100644
--- a/pixel.cpp
+++ b/pixel.cpp
@@ -16,7 +16,7 @@ long long convert(int n);
 int convertBinInt(long long n);
 
 
-void pixel(char key[16],
+void pixel(char key,
 		ap_int<32> position1,
 		ap_int<32> position2,
 		ap_int<32> stream_count,