def get_event_time_list(event_frame_list, f_to_t):
    """
    Given a list of starting and ending frames that represent events,
    ...compute the list of smoke event starting and ending epochtimes and the metadata

    Input:
        event_frame_list: list of starting and ending frames that represent events (from get_event_frame_list function)
        f_to_t: a dictionary that maps frame number to epochtime

    Output:
        event_time_list: the list of smoke event starting and ending epochtimes
        total_event_duration_in_secs: the duration of all the events in seconds
    """
    total_event_duration_in_secs = 0
    event_time_list = []
    for e in event_frame_list:
        start_t = f_to_t[e[0]]
        end_t = f_to_t[e[1]]
        event_time_list.append([start_t, end_t])
        total_event_duration_in_secs += end_t-start_t+1
    return (event_time_list, total_event_duration_in_secs)