Gets the predicted time at which this frame will be displayed.
Although no predicted time may be available, if one is available, it will be available while the frame is being generated, in contrast to get_presentation_time, which is only available after the frame has been presented. In general, if you are simply animating, you should use get_frame_time rather than this function, but this function is useful for applications that want exact control over latency. For example, a movie player may want this information for Audio/Video synchronization.
The predicted time at which the frame will be presented, in the timescale of get_monotonic_time, or 0 if no predicted presentation time is available.