The festival, the oldest and most prestigious event of its kind in the Spanish speaking world, usually pays tribute to one major star each year with a Donastia Award in honour of their career.
But this year organisers decided to award the prize to five major film figures -- McGregor, Travolta, Oliver Stone, Tommy Lee Jones and Dustin Hoffman.
"We wanted it to be people who are historical figures of cinema but who at the same time continue to make movies because we want to look at the past but at the same time we want to say that this festival, above all, has a future and thinks of the future," said Rebordinos.
All five stars who will receive a Donostia Award will see one of their recent works screened at the festival.
Hoffman, 75, will present his directorial debut "Quartet", which centres on a retirement home for opera singers and other musicians set in the English countryside. The movie will close the festival on September 29.
Also screening out of competition will be McGregor's latest film "The Impossible", a drama based on a true story of a family's fight to survive during the 2004 tsunami by Spanish director Juan Antonio Bayona.
Stone and Travolta will compete for an audience award in the Zabaltegi-Pearls section of the festival with their latest film "Savages", a crime thriller that also stars Salma Hayek and Blake Lively.
They face competition from Jones whose romantic comedy "Hope Springs" is in the run for an audience award as well.
The movie also stars Meryl Streep, who won a Donostia Award in 2008 but is not expected to attend the festival this year.
"We have made an effort to ensure that Hollywood films have a significant presence. The representation of American cinema at the festival is greater than in other years," said Rebordinos.
Among the other big-name stars who are set to attend the festival are Richard Gere, Susan Sarandon, Ben Affleck, Penelope Cruz, Benicio del Toro and Claudia Cardinale.
The focus on stars is part of an effort by organisers to give the festival a boost even as its budget has been cut in the midst of Spain's economic crisis.
"If despite the crisis San Sebastian wants to continue to be one of the main film festivals after Venice and Berlin, whose budgets are twice the size of ours, it has to increase its resources," said Rebordinos.
"We have to convince distributors that it is a festival that offers a splendid setting to promote their films and for that we need an important presence in the international press" who are attracted by stars, he added.
"The festival has to be a puzzle which has its dosis of glamour, its dosis of great cinema, the presence of the industry, but always keeping in mind that without good films no festival makes any sense."
Rebordinos said the festival will feature fewer films from Asia this year than in past editions "simply because we were able to bring over fewer of the films which we liked."
Young Chinese filmmaker Emily Tang will compete for the best picture Golden Shell award with her movie "All Apologies" which revolves around a man's struggle to accept the death of his son in a car accident.
Chinese director Hao Jie will compete for a prize in the new director category with his film "The Love Songs of Tiedan" while Japan will be represented by Kiyoshi Kurosawa and his television ministeries "Shokuzai".
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