Obtain $P_s(k,l)$ from $P_g(k,l)$ as follows:

Note that $H(0,0)=1$ and $P_s(k,l)P_s(0,0).$ Set $={10}^{-6}.$ # calculate P$\_$s$($k$,$l$)$ from P$\_$g$($k$,$l$)$ as described in the lecture slides

size$\_$Blur $=(15,15)$

noise$\_$var $=$ noise$\_$Std$**2$

kernel $=$ np$.$ones$($size$\_$Blur$)/$ np$.$prod$($size$\_$Blur$)$

H $=$ ft$.$fft$2($kernel$,$ P$\_$g$.$shape$)$ # Ensure the kernel is the same size as P$\_$g