diff --git a/src/BC1/BC1Encoder.cpp b/src/BC1/BC1Encoder.cpp
index 26283f2..17a7b17 100644
--- a/src/BC1/BC1Encoder.cpp
+++ b/src/BC1/BC1Encoder.cpp
@@ -21,6 +21,7 @@
 
 #include <algorithm>
 #include <array>
+#include <cmath>
 #include <cstdint>
 #include <memory>