A video allegedly showing the Costa Concordia captain set to abandon the sinking cruise liner with hundreds of passengers still on board has emerged, as he gave testimony on the tragedy for the second consecutive day in court.

Francesco Schettino is seen standing on a deck of the partially submerged ship near a lifeboat ready to leave, in footage filmed from the shores of Giglio Island which is being used as evidence against him by Italian prosecutors.

The captain is being tried on a series of charges including abandoning ship in relation to the shipwreck that killed 32 people in 2012.

Prosecutors allege he dithered in ordering the evacuation, which he then failed to coordinate properly, as he fled to safety leaving behind hundreds of terrified passengers.

Schettino denies the accusation, contending he fell from the liner as it rolled on its side.

However prosecutors say his claim is denied by images recorded by firefighters the night of the tragedy, in which he is seen in suit and tie waiting near a lifeboat that is being boarded by some crew members and passengers.

Concordia midshipman Stefano Iannelli earlier testified that Schettino jumped on a lifeboat and safely made his way to shore while passengers struggled in the water.

"As soon as the launch left, the ship collapsed on its side and the deck where we were was submerged," Iannelli told the court in the Tuscan town of Grosseto.

'Second only to God'

The video filed as evidence against the captain was leaked to Italian media as he took the stand to defend himself for a second time.

Yesterday, Schettino accused his former crew of behaving like students on a school trip during the shipwreck for not warning him of the impending danger as he steered the liner too close to the Giglio Island, apparently as a treat to passengers.

On the second day of testimony, Schettino claimed that as the captain he was "second only to God" on the Concordia, in a comment that outraged the Italian public.

He also maintained that he intentionally delayed raising the alarm after the liner crashed into a reef, not to trigger unnecessary panic among passengers.

"I wanted to bring the ship as close as possible to the island," he told the court, adding that an early alarm would have caused "people to jump" off the liner as it was still in deep water.

Earlier during the trial, lawyers for the victims played chilling recordings of frantic phone calls made to emergency services by disoriented passengers, who cried for help and directions as the ship was plunging into the waters.

"Help us please, they don't tell us anything," a passenger was herd telling an operator. "They slaughter us like sheep ... They don't want to launch lifeboats; the ship is slanting."

Schettino faces up to 20 years in jail on charges of manslaughter, causing a shipwreck and abandoning ship. He is the sole defendant and denies the charges.