Filters need to be re-applied to invalidated snapshots?

I have a snapshot that contains filled polygon shapes.  I apply filter.blurGaussian to the snapshot.

Since I need to visually enlarge my snapshot (around 4X) the polygons become jagged hence I set the horizontal.blurSize and vertical.blurSize = 4 which makes the jagged edges of the polygons less obvious.

However, when I invalidate the snapshot, the polygon lines become more jagged, as if the value of the filter.blurGaussian seems to have changed after the snapshot:invalidate(). 

Do we need to reapply filters to a snapshot each time it’s invalidated?