diff --git a/examples/heif_enc.cc b/examples/heif_enc.cc
index 060e79d151..abcfa2eca5 100644
--- a/examples/heif_enc.cc
+++ b/examples/heif_enc.cc
@@ -36,6 +36,7 @@
 #include <algorithm>
 #include <vector>
 #include <string>
+#include <sstream>
 
 #include <libheif/heif.h>
 #include <libheif/heif_properties.h>