def METHOD_NAME(self):
    # zero input should return dct(lin2db(0)). Try with different sizes
    size = 1025
    val = amp2db(0)
    expected = DCT(inputSize=40, outputSize=13)([val for x in range(40)])
    while (size > 256 ):
        bands, gfcc = GFCC(inputSize=size)(zeros(size))
        self.assertEqualVector(gfcc, expected)
        # also assess that the thresholding is working
        self.assertTrue(not np.isnan(gfcc).any() and not np.isinf(gfcc).any())    
        size = int(size/2)