The film was produced by Domenico Procacci, who also did the international hit "Gomorra," which won second place at Cannes this spring. But Procacci said there is no formula for worldwide success.
"Today it is very difficult to predict if a film will have a broader audience," Procacci told a news conference Saturday.
Cannes marked a long-awaited moment of recognition for Italian film. Besides the award for "Gomorra," Paolo Sorrentino's "Il Divo," a lively portrait of former Premier Giulio Andreotti, won the jury award.
Despite that success, there has been some criticism of the strong Italian presence in Venice.
The German weekly Der Spiegel accused the film festival of weighing down the lineup with Italian films, noting none had been captured the Golden Lion in recent years, in an effort to increase the profile of the Italian film industry. The festival is screening a total of 12 new Italian full-length features, compared to 10 Hollywood productions.
Italy's Culture Minister Sandro Bondi said he was perplexed by the criticism, noting that the festival long had taken heat for not having enough Italian fare.
"Their presence this year reflects, as has just been demonstrated at the Cannes festival, that our cinema is returning to levels of excellence," Bondi said, noting that the Italian presence would also be strong at the Toronto film festival, which starts next week, as well as at film festivals in London, Tokyo and South Korea in October.
Venice Film Festival director Marco Mueller has said nationality has played no role in the lineup choices.
The jury is still out on whether Italian film is experiencing a renaissance, but certainly filmmakers are taking on tough themes that are finding broader appeal.
"It is a strong year for Italian cinema," Mueller said in an interview before this week's festival opening. "For us, what is really very refreshing is the fact that we in Venice can present a wide spectrum of all the possible roads open to Italian cinema. We have filmmakers who are very diverse."
"A Perfect Day," is directed by the Turkish-born Ozpetek, who won the best director Golden Globe for 2005's "Sacred Heart."
Ozpetek said he toned down some of the violent scenes in Melania Mazzucco's novel "because on screen they would become magnified, almost unbearable to watch."
Pupi Avati's "il papa di Giovanna," about a father's relationship with his troubled adult daughter, premieres Sunday.
The other Italian films competing for the Golden Lion are Pappi Corsicato's story about a woman who has to explain her pregnancy to her husband on the day he discovers that he is sterile and Marco Bechis' "Birdwatchers," a movie set in Brazil centered on the conflict between wealthy plantation owners and the native inhabitants of the land.