diff --git a/openbr/openbr_plugin.h b/openbr/openbr_plugin.h
index 3a8aa85..4ae25a7 100644
--- a/openbr/openbr_plugin.h
+++ b/openbr/openbr_plugin.h
@@ -354,7 +354,7 @@ struct Template : public QList<cv::Mat>
     inline const cv::Mat &m() const { static const cv::Mat NullMatrix;
                                       return isEmpty() ? qFatal("Empty template."), NullMatrix : last(); } /*!< \brief Idiom to treat the template as a matrix. */
     inline cv::Mat &m() { return isEmpty() ? append(cv::Mat()), last() : last(); } /*!< \brief Idiom to treat the template as a matrix. */
-    inline const File &operator()() const { return file; }
+    inline operator const File &() const { return file; }
     inline cv::Mat &operator=(const cv::Mat &other) { return m() = other; } /*!< \brief Idiom to treat the template as a matrix. */
     inline operator const cv::Mat&() const { return m(); } /*!< \brief Idiom to treat the template as a matrix. */
     inline operator cv::Mat&() { return m(); } /*!< \brief Idiom to treat the template as a matrix. */