The NBA formally announced its 2012 Sprite Slam Dunk Contest participants on Thursday via Twitter for All-Star Weekend in Orlando. The dunk contest will take place on Feb.25 at 8:30 p.m. ET on TNT.

All four competitors in the 2012 dunk field are first-timers. They include New York Knicks rookie guard Iman Shumpert, Minnesota Timberwolves rookie forward Derrick Williams, Houston Rockets forward Chase Budinger and Indiana Pacers forward Paul George.

Clippers forward Blake Griffin's dunk over a car in last year's slam dunk contest at the Staples Center in Los Angeles solidified his win. (Reuters)

Of the four, George is the leader in dunks this season with 20.

Los Angeles Clippers forward Blake Griffin confirmed that he will not defending his dunk title. Griffin won the title at Staples Center last season, most notably for leaping over the hood of a car and slamming home a lob from then-teammate Baron Davis peered out of the sun roof.

According to reports, the dunk contest will have a new format which will consist of only one round and in which the winner will be solely determined by fan vote-via Twitter for the first time, in addition to online and text voting. Each participant will get three dunks, with fan voting to open after the foursome completes their first dunks.

Previous contests had dunkers complete two rounds, with the first scored by a panel of courtside judges which determined the two finalists.

Sources also told ESPN.com that Shumpert will be enlisting New York Knicks sensation Jeremy Lin to assist him in a manner similar to the help Griffin got last year from Davis. With Lin-sanity raging, Shumpert, even despite an unimpressive performance, could be the favorite then.

<a href=http://polldaddy.com/poll/5949681/ mce_href=http://polldaddy.com/poll/5949681/>Who's your early favorite to win the 2012 Sprite Slam Dunk Contest?</a>

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