Walmart said Thursday that people can now use its Vudu app to convert their existing DVDs and Blu-Rays into digital movies that they can watch online.

Vudu is Walmart’s (WMT) video streaming service that it bought in 2010 for a reported $100 million. Unlike other online streaming services like Netflix (NFLX) or Amazon Prime (AMZN), Vudu customers pay no monthly subscription fee, but can instead rent or buy individual titles to watch online.

Get Data Sheet, Fortune’s technology newsletter.

In order to convert disks into digital, Vudu users scan the barcodes on the DVD or Blue-Ray boxes with the Vudu apps, and then choose whether to convert the disks into standard or high-quality streaming files. A high-definition upgrade with improved visuals costs $5 while a lower-quality stream costs $2.

Technically, the app isn’t really converting physical discs into digital files. The new service essentially lets people buy movies more cheaply from Vudu as long as they have their old DVD or Blu-Ray boxes.

For example, a newly released movie on Vudu, like the Academy award-winning film Moonlight, can cost $15 for a high-quality digital file. With the latest marketing gimmick, users can get the same film for a third of the list price.

For more about finance and technology, watch:

Not every Blu-Ray or DVD is eligible for the new service. Walmart said that it only supports around 8,000 movies from studios like Lionsgate, Paramount Home Media Distribution, Sony Pictures Home Entertainment, Twentieth Century Fox Home Entertainment, Universal Pictures Home Entertainment and Warner Bros. Home Entertainment.

Update Friday Mar. 24: Corrected spelling of Vudu