3D technology hasn’t saved TV.

People are watching less broadcast and cable TV, according to a survey from Accenture. Less than a third intend to buy a new TV in 2012. Smartphones, tablets and computers are eroding traditional TV viewing — bad news for TV manufacturers and traditional content providers.

The online survey of 10,000 adults in 10 countries, including 1,000 in the U.S., found that the percentage of people watching broadcast or cable TV in a typical week on televisions fell from 71 percent in 2009 to 48 percent in 2011. The percentage of consumers who intend to buy a TV set during the next 12 months also declined, from 35 percent in 2010 to 32 percent in 2011.

“Craving an always-on, always-connected lifestyle, consumers increasingly are using other consumer electronics devices in their daily lives to access the entertainment that only TV once provided,” Mitch Cline, global managing director of Accenture’s Electronics & High-Tech Group, said in a statement.

More than half (56 percent) of the survey respondents indicated they have changed their behaviors due to online services and cloud computing. Nearly one-third (32 percent) have stopped, or almost stopped, renting or buying DVDs and 26 percent stream media content. In a typical week, 33 percent of consumers now watch shows, movies or videos on their PCs, and 10 percent are watching such programs on their smartphones .

Key to wooing TV buyers

Accenture asked online consumers what would make them more inclined to buy a TV. Affordability trumped fancy — and often pricey — features. More than half (55 percent) indicated they would purchase a television if the price was within their budget.

High-definition resolution was cited by 42 percent of the respondents as a reason to buy a new HDTV. Only one-fourth said they would buy a new TV bec ause it offered 3D or Internet access.