Sarah Gardner: As of today, you can go into your local Walmart and turn your old DVDs and Blu-Ray discs into an online movie library. Might not seem like such a big deal. After all, you already own the movies: They’re sitting in those little jewel cases gathering dust on the shelves in your TV room — I meant, ‘entertainment center.’

But now, for a fee, Walmart will let you stream them to your iPad or smartphone, or download them to your PC, which means you can watch “Pet Sematary Two” or “Friday the 13th” pretty much wherever and whenever.

Marketplace’s Mitchell Hartman has the lowdown on this new download.

“Shrek” clip: Roar! That was really scary — your breath will certainly get the job done.

Mitchell Hartman: All of that “Shrek” video your kid pestered you to buy could be yours to stream via the Internet in perpetuity for $2 from Walmart, says spokesperson Sarah Spencer.

Sarah Spencer: We know that there’s movies kind of collecting dust, you know, just sitting in living rooms, that they can’t watch on their new iPads, they can’t watch on their PCs, their Macs when they’re on the go, if they’re on vacation and they’ve got the kids and it’s raining in Orlando and you want to watch something.

Sounds scary. What’s scary for Walmart, though, is that people aren’t buying as many new DVDs and Blu-Rays. Sales are down by as much as half, says Jonathan Taplin at the USC Annenberg School.

Jonathan Taplin: The problem with the owning model is that people have really abandoned that. I think with the exception of the Disney film that maybe your daughter wants to watch 10 times, there’s not a whole lot of evidence people want to watch and own movies the way they want to own music content.

Taplin says people are willing to buy songs for their iTunes libraries, to access later whenever they want. But consumers prefer to rent movies and TV shows — and watch them just once — using a rival service, like Netflix.

But Taplin says movie studios make more money if you buy the digital rights. And that’s why they’re pushing the Walmart model.

I’m Mitchell Hartman for Marketplace.