Should ALOS-PALSAR Level1.1 images (SLC) be geocoded before any other processes are applied or not?

Question

I am processing PALSAR L1.1 images from SLC to Geocoded/Filtered products. I am testing various types of filters using ENVI software.

My question is should I apply the filter (Lee, Gammma, etc.) before or after geocoding?

SLC images are first converted to 'Multilook' images.

Thanks, Pierre