ASSERT (_x0 == _y1);
    public void init(int _x0, int _y0, int _x1, int _y1)    {        x0 = _x0;        y0 = _y0;        x1 = _x1;        y1 = _y1;        input = new Channel(Float.TYPE, _x0 * _y0 + _x1 * _y1);        output = new Channel(Float.TYPE, _y0 * _x1);    }