Terrain Smooth with Script

Hi guys, currently im creating a terrain generator and i achieve the result as shown on the image above with this guide.

But this is not enough for me, i need to smooth the terrain. As the terrain is adjust in run time, so terrain tool kit in unity editor is unusable. My friend suggest me to use Gaussian Blur algorithm to do the smoothing.

In the other tips or guide to do the smoothing?

Thanks for reading and happy answering