Best Actress nominee Jennifer Lawrence for her role in "Silver Linings Playbook", wearing a white Dior Haute Couture gown, poses at the 85th Academy Awards in Hollywood, California in this February 24, 2013 file photo. [Photo/Agencies]

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That bonus air-time for a single dress at one of the world's premier global events is priceless for the likes of Dior, one of the strongest fashion houses in the cutthroat marketplace that the Oscars red carpet is today.

Success on the red carpet can buy cachet that no advertising can - both for designers and stars - and profits for luxury brands for years to come. With stakes that high, the more established houses are raising their game and leaving little room for newcomers to make a splash, like they might have a decade ago.

The red carpet, which will be televised live before the March 2 Academy Awards ceremony, presents "a great and free opportunity" for a designer to reach an audience that expands beyond the fashion set, said Ariel Foxman, editor of fashion magazine InStyle.

"It's free marketing," Foxman said. "Advertising dollars are so expensive, and marketing budgets are so fractured these days with social media, digital media, print media and television media, so it's more valuable than ever."

One way of estimating the monetary benefits of having a standout dress on the red carpet is to compare how much a brand would otherwise spend on commercial advertising during the same time, said Milton Pedraza, chief executive officer of the Luxury Group Institute, a consulting firm.

According to a report by Kantar Media released this week, the average cost of a 30-second advertising spot during the 2013 Oscars was $1.65 million. The show was watched by 40.3 million viewers in the United States and several hundred million more across the world.

For Lawrence's 2013 Oscar acceptance speech and her accidental trip on the stairs to the stage, she had more than 75 seconds of solo camera time. For a commercial spot of the same duration at the same time, Dior would have had to pay more than $4 million. And this doesn't include the time dedicated to Lawrence and her gown on the pre-show televised red carpet.

For this year, Kantar Media estimates that a 30-second advertising spot will cost brands an average of $1.8 million during the primetime show.

Lawrence, 23, who is nominated again this year in the best supporting actress category for "American Hustle," is a Dior brand ambassador, wearing the Paris fashion house's designs to all her public events.

While Christian Dior group has not disclosed how much it paid for its deal with Lawrence and doesn't discuss her impact on its sales, the high-end couture label is on the rise. In 2013, couture's profits totaled 165 million euros ($226 million), up 26 percent from 2012.