diff --git a/media/libstagefright/include/media/stagefright/MPEG4Writer.h b/media/libstagefright/include/media/stagefright/MPEG4Writer.h
index 054a4b8..18237e5 100644
--- a/media/libstagefright/include/media/stagefright/MPEG4Writer.h
+++ b/media/libstagefright/include/media/stagefright/MPEG4Writer.h
@@ -77,6 +77,9 @@
     virtual void setStartTimeOffsetMs(int ms) { mStartTimeOffsetMs = ms; }
     virtual int32_t getStartTimeOffsetMs() const { return mStartTimeOffsetMs; }
     virtual status_t setNextFd(int fd);
+    bool isSampleMetadataValid([[maybe_unused]] size_t trackIndex, int64_t timeUs) override {
+        return timeUs >= 0;
+    }
 
 protected:
     virtual ~MPEG4Writer();