diff --git a/tests/tiny_psnr.c b/tests/tiny_psnr.c
index a53a67038bcefa0d584eefdaca9e5101804d8ed8..b1bcc166937b99b82b88bd0e8c0ddc223e0f5f6d 100644
--- a/tests/tiny_psnr.c
+++ b/tests/tiny_psnr.c
@@ -146,7 +146,7 @@ int main(int argc, char *argv[])
         }
     }
 
-    max = (1 << (8 * len)) - 1;
+    max = (1LL << (8 * len)) - 1;
 
     f[0] = fopen(argv[1], "rb");
     f[1] = fopen(argv[2], "rb");