[How can get the playbacktime of video when using Spanipal SDK to get gaze data?]

My requirement is that when users use HTC Vive Pro Eye to watch panoramic videos, I record the time stamp, video playback time, and eyeball position data.

The official SRanipal SDK C source code solved most of my problems. But I don’t know how to record the playbacktime of video when the user watches the video. 

In addition, there is a structure about eyeball information in the C source code, in which I am very curious about timestamp which indicates the time when the frame was capturing in millisecond

// The code is in SRanipal_EyeData_v1.h which is offically provided.

namespace ViveSR {
	namespace anipal {
		/**
		* Eye module
		*/
		namespace Eye
		{
			/** @struct EyeData
			* A struct containing all data listed below.
			*/
			struct EyeData
			{
				bool no_user;
				int frame_sequence;/*!<The frame sequence.*/
				int timestamp;/*!<The time when the frame was capturing. in millisecond.*/
				VerboseData verbose_data;
			};
		}
	}
}