Redbox has become the most popular source of DVD and Blu-ray disc rentals.

Redbox has become the most popular source of DVD and Blu-ray disc rentals, according to an NPD survey released Thursday, which revealed a sharp drop in rival services, including Netflix.

NPD's VideoWatch tracker, which surveyed over 38,600 movie renters and an additional 74,000 Blu-ray renters, noted a marked shift away from the renting of physical discs themselves, with more and more consumers turning to streaming instead.

NPD said that consumer rentals of DVDs and Blu-ray discs fell by 11 percent versus the prior year. Nearly one in three video rentals actually occured either online or via on-demand cable, which NPD lumped together as a single video-on-demand service.

"The movie-rental market is clearly undergoing a sea change, as consumers become better equipped to access on-demand and streamed movies and are more comfortable with available delivery options," said Russ Crupnick, senior vice president of industry analysis for NPD, in a statement. "Even so renting physical discs from now-ubiquitous kiosks in grocery stores and other venues has taken the lead as the most popular movie-rental method in the U.S."

Redbox, owned by Coinstar, dominated the physical DVD/Blu-ray disc rental space, increasing its market share from 25 percent a year ago to 37 percent in 2011. Redbox's unit volume climbed 29 percent, even as it raised prices. (See Coinstar's other kiosk ideas, including Gizmo, an "eBay in a box".)