function makeVideoStep() {
	var next = parseInt(jQuery("#main_video_img").attr('seq')) + 1;
	if(next == 4) next = 1;
	jQuery("#main_video_img").attr('src', "/images/step" + next + ".jpg")
	jQuery("#main_video_img").attr('seq', next);
	setTimeout('makeVideoStep()', 4000);
}