How to set the starting point of videos?

I'd like to make a code which play portions of a loaded video, setting the starting point and the duration of those portions of clip. It is a sort of random granular playback.

How can I play a clip from a starting point which is not the beginning of a loaded clip? How can I set the duration of the grains?

I'm using the default video library.

import processing.video.*;

Movie video;

void setup() {
  size(600, 400);
  video = new Movie(this, "station.mov");
  video.loop();
}

void movieEvent(Movie video){
  video.read();
}

void draw() {
  image(video, 0, 0);
}