public com.google.cloud.videointelligence.v1.ObjectTrackingFrameOrBuilder getFramesOrBuilder(
        int index) {
      if (framesBuilder_ == null) {
        return frames_.get(index);
      } else {
        return framesBuilder_.getMessageOrBuilder(index);
      }
    }
<pre>
Information corresponding to all frames where this object track appears.
Non-streaming batch mode: it may be one or multiple ObjectTrackingFrame
messages in frames.
Streaming mode: it can only be one ObjectTrackingFrame message in frames.
</pre>

<code>repeated .google.cloud.videointelligence.v1.ObjectTrackingFrame frames = 2;</code>
java-video-intelligence/proto-google-cloud-video-intelligence-v1/src/main/java/com/google/cloud/videointelligence/v1/ObjectTrackingAnnotation.java