The Gold Coast couple who captured viral footage from aboard a cruise ship as it crashed into a Venice pier say they couldn't believe what they were seeing as the drama unfolded.

Key points: The MSC Opera experienced a loss of control, according to an audio clip from the pilot

The MSC Opera experienced a loss of control, according to an audio clip from the pilot The ship, built in 2004, can carry over 2,675 passengers

The ship, built in 2004, can carry over 2,675 passengers The accident has reignited calls for a ban on large vessels entering Venice's canals

Like a scene from a disaster movie, the MSC Opera cruise ship lost control and ploughed into the dock at the San Basilio Cruise Terminal before hitting a smaller tourist boat.

Robert and Rita Lauretti recorded vision of the incident, which has now been shared worldwide, from their cabin balcony.

"Oddly enough, this morning we decided to have breakfast on our balcony with a couple of friends, and that's what we were doing when the ship hit," Mr Lauretti told ABC Radio Brisbane's Rebecca Levingston.

Robert and Rita Lauretti were on the cruise ship when it struck trouble. ( Supplied: Robert Lauretti )

"A minute-and-a-half prior to taking the video, I thought we were taking a weird angle coming into the place.

"Then I could see the tug boat working hard to try and pull us to the left and I realised there was a problem.

"I went and grabbed my phone and started to film."

Officials said five women, including two Australians and a New Zealander, aged between 67 and 72, were injured as they tried to run away from the ship.

Mr Lauretti said his wife and friends were left shaken but safe considering the circumstances.

"We're not too bad ... it was a bit hard to take in because we couldn't believe it was happening," he said.

"It was all in slow motion as it wasn't going fast at all.

"We had decided at the start of our trip to take the top deck cabin facing forward so we could get a good view of each port we come into."

A tourist boat was struck by the towering cruise ship in Venice. ( AP: Luca Bruno )

Staying calm despite the noise

The MSC Opera was built in 2004. It can carry more than 2,670 passengers in 1,071 cabins.

According to its sailing schedule, it left Venice on May 26 and travelled to Kotor, Montenegro and Mykonos, Santorini and Corfu in Greece before returning to Venice.

During the crash, you can hear in the video Mr Lauretti trying to remain calm.

"I wasn't worried about our ship banging into the dock, I was more worried about the river cruiser that we could have smashed into," he said.

"Watching people running in circles jumping left and right trying to get off the cruiser was scary.

"I watched a lady get flipped upside down in the air on the river cruiser as she tried to get down the stairs.

"As we hit the boat, I'm surprised how little we felt as we impacted ... it wasn't a loud bang at all."

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 1 m Bystanders run in panic as towering ship bears down on them

'Lightning doesn't strike twice ... '

Mr Lauretti said some passengers believed the incident occurred due to a mechanical fault, yet others told him there was a ferry in front of the cruise ship which made it veer off course.

"Luckily the pilot managed to steer the ship to the right-hand side of the boat and get between the pier and the boat before pushing the boat outwards, rather than hit it the other way.

"If he did that, there would have been fatalities for sure."

Following the impact, he said passengers did not hear any instructions over the ship's PA system for at least five minutes.

The boat did not move for five hours and nobody was allowed to disembark until authorities had given the all clear.

"Our cruise was only an eight-day cruise and we were only 24 hours into it," Mr Lauretti said.

"We will stay on the cruise as I'm sure lightning doesn't strike twice.

"My wife has been beating my head for 20 years or more to get me on a cruise, and finally I agree and in less than 24 hours this happens."

An investigation has been launched and the cruise ship company said it was cooperating with authorities.