I guess its called Gaussian Blur, check this: http://www.quasimondo.com/StackBlurForCanvas/StackBlurDemo.html
Scary and amazing at the same time!
You should ask this question the author of the plugin in the comments where you bought the file.
Congrats on your sales!
Its not a wordpress plugin but you can embed it using iframe.
I have an audio player which pauses or stops other songs while new is being played if you are interested.
Try in the discussion section of the file you bought:http://codecanyon.net/item/jquery-banner-rotator-content-slider-carousel/discussion/1534434