Help with removing overly heavy wall texture

I just purchased a home that has some pretty heavy wall texture applied to several of the walls. Looks like someone bought one of those texture design rollers from menards, put tons of mud on the wall and went to town! It is so thick it spikes out from the walls at least a 1/2 to 3/4 inch in most areas. It has several coats of paint over it. I need to know the most effective way to scrape this smooth?? doing it with hand scrapers does not seem doable or desirable. Is there a tool that exists that I could buy or rent to get this accomplished? Anyone else ever dealt with this? Thank you in advance! Frank