SimpleBlurTransformation (With Picasso)

 public static class BlurTransformation implements com.squareup.picasso.Transformation {
        private final float radius;

        private Context mContext;
        // radius is corner radii in dp
        public BlurTransformation(final float radius, Context context) {
            this.radius = radius;
            this.mContext = context;
        }

        @Override
        public Bitmap transform(final Bitmap source) {
            int width = Math.round(source.getWidth());
            int height = Math.round(source.getHeight());

            Bitmap inputBitmap = Bitmap.createScaledBitmap(source, width, height, true);
            Bitmap outputBitmap = Bitmap.createBitmap(inputBitmap);

            RenderScript rs = RenderScript.create(mContext);
            ScriptIntrinsicBlur theIntrinsic = ScriptIntrinsicBlur.create(rs, Element.U8_4(rs));
            Allocation tmpIn = Allocation.createFromBitmap(rs, inputBitmap);
            Allocation tmpOut = Allocation.createFromBitmap(rs, outputBitmap);
            theIntrinsic.setRadius(radius);
            theIntrinsic.setInput(tmpIn);
            theIntrinsic.forEach(tmpOut);
            tmpOut.copyTo(outputBitmap);

            return outputBitmap;
        }

        @Override
        public String key() {
            return "blur" + Float.toString(radius);
        }
    }
}