def demo_steerablederiv():
"""Display the kernel of a steerable derivative filter."""
import imageutils
S = imageutils.steerable_deriv(sigma=14.1, n_pix=61)
imageutils.imshow(S)
imageutils.plt.xlabel('x pixel')
imageutils.plt.ylabel('y pixel')
imageutils.plt.title('Steerable derivative; sigma = 14.1, 61 pixels')
imageutils.plt.colorbar()
imageutils.plt.show()
def SteerableDerivativeMetric(self, field, opts):
steerable_filter = imageutils.steerable_deriv(sigma=1.5)
S, _, _, _ = imageutils.apply_gradient_filter(numpy.abs(field,
steerable_filter))
return S
