diff --git a/coders/sfw.c b/coders/sfw.c
index 345dcb0..0d02e44 100644
--- a/coders/sfw.c
+++ b/coders/sfw.c
@@ -155,7 +155,7 @@
 
 static Image *ReadSFWImage(const ImageInfo *image_info,ExceptionInfo *exception)
 {
-  static unsigned char
+  static const unsigned char
     HuffmanTable[] =
     {
       0xFF, 0xC4, 0x01, 0xA2, 0x00, 0x00, 0x01, 0x05, 0x01, 0x01, 0x01,