Top Hollywood talent and auteur directors will be vying for the Golden Lion at the world's oldest film festival. 

The Venice Film Festival has been seen as a launch pad for the industry's award season, after premiering Academy winners in its last four editions. 

The event starts from Wednesday evening. The festival venue on the Venice Lido was a scurry of activity on the eve of the event's opening day with workers yet to lay out the red carpet outside the Palazzo del Cinema. 

Alexander Payne's "Downsizing", a satire about a couple who decide to shrink themselves to four inches tall, starring Matt Damon, Kristen Wiig and Christoph Waltz will open the festival on Wednesday evening. The film will compete for the Golden Lion against 20 other movies including Guillermo Del Toro's "The Shape of Water" and the unexpected addition of Darren Aranofsky's "Mother!", a horror movie starring Jennifer Lawrence. 

George Clooney returns to the Venice water-front with "Suburbicon", a dark comedy which he directed. The film stars Damon and Julianne Moore. Moviemakers will be hoping for a replay of the success of films such as "Spotlight", "La La Land", "Gravity" and "Birdman" which went from Venice launches to Academy Awards success.

"Angels Wear White", directed by Vivian Qu, has been selected to be screened in the main competition section. Vivian Qu produced "Black Coal, Thin Ice" in 2004, which won that year's Golden Bear Award at the Berlin Film Festival. Security measures have been stepped up on the Venice Lido ahead of the festival which runs from Aug. 30 until Sept. 9.