def __init__(self, nfilters, filterx=3, filtery=3, compiled=True, **kw):
        super().__init__(compiled=compiled, **kw)
        self.nfilters = nfilters
        self.fx = filterx
        self.fy = filtery
        self.depth = 0
        self.stride = 1
        self.inshape = None
        self.op = None