diff --git a/op_c.c b/op_c.c
index 415008ce..fa3cbb8f 100644
--- a/op_c.c
+++ b/op_c.c
@@ -203,7 +203,7 @@ T_Conversion_table * CT_new(int nbb_r,int nbb_g,int nbb_b)
 
     // Allocate the table
     size=(n->rng_r)*(n->rng_g)*(n->rng_b);
-    n->table=(byte *)malloc(size, 1);
+    n->table=(byte *)calloc(size, 1);
     if (n->table == NULL)
     {
       // Not enough memory