Pacino received the Jaeger-Lecoultre Glory to the Filmmaker Award at a gala awards ceremony.
Wilde Salome is part-documentary about the staging of Irish writer and poet Oscar Wilde's play Salome, starring rising star Jessica Chastain, part-exploration of the author and part-film version of Salome itself.
Pacino admitted to being a little confused about what type of picture he had made.
"I guess what I tried to do is ... create a story," Pacino said.
"But I don't know what it is. I like to say it's a documentary because it's not a film, but then it's not a documentary either, so I'm confused too."
Pacino said Wilde, who was hounded for his homosexuality at the end of the 19th century, was a fascinating subject.
"We do know that he was ... a very liberal thinker and more than that he was a visionary in terms of his feeling for people and how he wanted society to be more humane and that he was really on dangerous ground at that time.
"Part of his sexuality was what they used against him to put him away. They wanted to silence him."
Asked what the future held, Pacino replied:"I have movies that are still coming at me and I always say that I'm going to be selective. I always say that, but I never am.
"I'm saying again - 'I'm going to do it only when I feel it's the thing to do for me.' I hope I follow that philosophy. That's my future."
Between the recognised titans of the discipline, Sigmund Freud and Carl Jung, played by Viggo Mortensen and Michael Fassbender respectively, came Sabina Spielrein, portrayed by Keira Knightley.
The psychologically troubled, fiercely intelligent young woman was a real-life patient first of Jung and later of Freud.
Some historians believe she had an affair with Jung, and in the film he sets out on a path of sexual liberation and obsession with his charge, prompted by the debauched and dangerous Otto Gross.
For Knightley, a role involving scenes of hysteria and sexual spanking was a departure from the demure, restrained characters for which she is best known.
Asked whether she enjoyed the role, she told reporters in Venice where the film has its world premiere: "It's great fun. I'm an actress so I'm obviously crazy anyway so I think I drew on that. It's fine."
Cronenberg joked that he chose his cast based on their need for treatment.
"I'd like to just say that my cast has a great need of psychoanalysis - it was why I cast them actually.
"It was to sort of introduce them gently to the idea that they needed help, a lot of help. And you can see they're much better people. Before they were messes when I found them."
Spielrein went on to become a respected psychoanalyst in her own right and in the film her ideas challenge both Freud and Jung to rethink their own approach.
Cronenberg said his cerebral costume drama about what he called an "intellectual menage a trois" was "very accurate."
"There's so much in the letters," said the 68-year-old director of hits like The Fly and A History of Violence.
"At this era in Vienna there were maybe five to eight mail deliveries every day. It was like the internet before the internet.
"There are tonnes of letters amongst all these characters and in those letters they quote each other ... So there's a lot of material out there which is the basis for the screenplay."
Oscar-winning writer Christopher Hampton penned the script, which is based on his own play The Talking Cure.
Cronenberg said Freud's ideas were considered dangerous at a time when many people believed man was on a one-way path to enlightenment and progress.
"Freud, with psychoanalysis, said this is not true, this is a very thin veneer of so-called civilisation ... and that these ... unconscious things could erupt in a very disastrous way.
"This was on the eve of the First World War, which of course ended the dream of progress and so-called European civilisation."
It is the second lead role for Fassbender in a competition movie at this year's festival after his portrayal of psychoanalyst Carl Jung in David Cronenberg's A Dangerous Method.
In Shame, the German-born Fassbender is Brandon, a handsome, 30-something executive living in New York whose only distraction from work is seducing women, masturbating at home or in the office and looking for sex on the internet. The tightly controlled rhythm of his life begins to fall apart when his needy, dysfunctional sister Sissy, played by Carey Mulligan, arrives for an unannounced visit.
Her presence, and her craving for Brandon's attention, disrupt his lonely existence even further, and his only way out seems to be wandering the streets at night in search of new sexual adventures.
McQueen, whose debut film was the widely acclaimed Hunger, about the last months of Irish Republican Army activist Bobby Sands in Belfast's Maze prison, said he saw similarities between the two films.
Hunger also starred Fassbender in the lead role.
"Clearly Hunger was a political film but Shame is also political. That one was about a prison in Northern Ireland, this one it's about how someone's freedom can actually imprison them and they need an addiction in order to numb a pain, how our lives have been changed sexually by the internet," he said.
The title Shame was chosen after interviews with sex addicts in preparation for the film. "The word shame came cropping up in those interviews," McQueen said.
