def clip(X, lcorr):
    """ perform 2D fftshift and crop with lcorr """
    x00 = X[:, :lcorr + 1, :lcorr + 1]
    x11 = X[:, -lcorr:, -lcorr:]
    x01 = X[:, :lcorr + 1, -lcorr:]
    x10 = X[:, -lcorr:, :lcorr + 1]
    return x00, x01, x10, x11
