Dali is an image blur library for Android. It is easy to use, fast and extensible. Dali contains several modules for either static blurring, live blurring and animations. It uses RenderScript internally (although different implementations can be chosen) and is heavily cached to be fast and keeps small memory footprint. It features a lot of additional image filters and may be easily extended and pretty every configuration can be changed.
It is open source and can be found here: https://github.com/patrickfav/Dali