Cotillard lip-synched over the original Piaf songs

Titled La Vie en Rose, it is one of 22 films in competition for the Golden Bear award - the winner will be announced on the 17 February.

Actors Willem Defoe and Gael Garcia Bernal, both members of the festival jury, attended the premiere.

Marion Cotillard stars in the lead role. Other films competing include Robert De Niro's The Good Shepherd.

Front-runner

Cotillard, who was last seen in Ridley Scott's A Good Year, is being tipped as an early favourite for the festival's best actress prize.

The French actress portrays Piaf from the age of 20 until her death at the age of 47, including the singer's rise to fame, her tempestuous private life and her struggles with alcohol.

Stars gather at the opening of the Berlinale

Cotillard lip-synched over the original Piaf recordings.

"It wasn't just an imitation of Edith Piaf," she told reporters.

"I wanted to do more than that - I wanted to bring her to life and we all did that together."

Steven Soderbergh's The Good German is also in competition - set in war-torn Berlin in 1945, it stars Cate Blanchett, Tobey Maguire and George Clooney.

Clooney is unable to attend the festival this year.

"He sends his love and will be back next year," said festival director Dieter Kosslick.

The Berlin Film Festival, now in its 57th year, runs for two weeks and will showcase 373 films during that time.

This year, the festival is dedicated to Bonnie And Clyde director Arthur Penn, who will be presented with an honorary award.