Gaussian Filter
[Separable filter](https://texonom.com/separable-filter-70c9a94159c64cbe85080f9ddf586c47) [Blurring](https://texonom.com/blurring-f58ae9e3896b46339396aacba739bbfc) 


$$f(i,j) = \frac{1}{2\pi\sigma^2}e^{-\frac{i^2 + j ^2}{2\sigma^2}}$$
 unlike [Box Filter](https://texonom.com/box-filter-0d975966a9474accb02603c75baafb0c), it doesn’t have some weird line

[Difference of Gaussians](https://texonom.com/difference-of-gaussians-2b069335c30a49ce96ae259109aef280)

usually truncate at 2-3σ 
 







