diff --git a/src/android/camera_metadata.h b/src/android/camera_metadata.h
index 75a9d706..348a0181 100644
--- a/src/android/camera_metadata.h
+++ b/src/android/camera_metadata.h
@@ -17,7 +17,7 @@ public:
 	CameraMetadata(size_t entryCapacity, size_t dataCapacity);
 	~CameraMetadata();
 
-	bool isValid() { return valid_; }
+	bool isValid() const { return valid_; }
 	bool addEntry(uint32_t tag, const void *data, size_t data_count);
 
 	camera_metadata_t *get();