The BlurFilter applies a gaussian blur to an object. The strength of the blur can be set for x- and y-axis separately (always relative to the stage).
A blur filter can also be set up as a drop shadow or glow filter. Use FilterFactory to create such a filter.
For each blur direction, the number of required passes is ceil(blur).
blur = 0.5: 1 pass
blur = 1.0: 1 pass
blur = 1.5: 2 passes
blur = 2.0: 2 passes
etc.