diff --git a/api/test/mock_transformable_video_frame.h b/api/test/mock_transformable_video_frame.h
index 749d2bddab..21c4dc2b69 100644
--- a/api/test/mock_transformable_video_frame.h
+++ b/api/test/mock_transformable_video_frame.h
@@ -37,6 +37,10 @@ class MockTransformableVideoFrame
               (),
               (const, override));
   MOCK_METHOD(VideoFrameMetadata, Metadata, (), (const, override));
+  MOCK_METHOD(absl::optional<Timestamp>,
+              GetCaptureTimeIdentifier,
+              (),
+              (const, override));
 };
 
 static_assert(!std::is_abstract_v<MockTransformableVideoFrame>, "");