Teen Choice Awards 2012: 'Sparkle' Star Jordin Sparks Talks 'Incredible' Whitney Houston (Video)

The "American Idol" alum tells THR that the process of promoting her first feature film has been "bittersweet," but insists that her idol is "up there watching."

While Jordin Sparks makes her big-screen debut this summer, playing the title character in Sony's Sparkle remake, the film will ultimately be remembered as Whitney Houston's last -- not as Sparks' first.

But that's not to say Sparks won't shine.

PHOTOS: Whitney Houston 1963-2012: The Iconic Singer's Life and Career in Pictures

The American Idol season six winner gained legions of fans during her time on the Fox reality competition, and most recently, Sparks wowed audiences of the Billboard Music Awards by paying tribute to the late Houston with a rousing rendition of her iconic ballad "I Will Always Love You."

"She is probably the reason why I got through singing her song at the Billboard awards," Sparks told The Hollywood Reporter at the Teen Choice Awards on Sunday. "That was one of the scariest things I've ever done."

Speaking with press at the Gibson Amphitheater on Sunday is only the beginning of what will likely become a a full-blown media blitz as Sparks promotes her upcoming film, due out Aug. 17. The project was expected to be part of a comeback for the late Houston, who died on Feb. 11 of accidental drowning at the Beverly Hilton Hotel.

"It's really bittersweet because I got to have that experience with her and now, she's not here to see the final product," said Sparks. "But she is seeing it. She's up there watching."

VIDEO: Whitney Houston's 'Sparkle' Trailer Debuts

"This was her baby," Sparks added. "It was huge for her, so now I'm trying to represent it as best as I can."

Despite the obvious footnote that will forever be attached to Sparkle, Sparks believes that there is also opportunity to remember Houston's life and to publicly acknowledge her own personal experiences working with her idol.

"It's amazing because we get to [talk about] the last couple months that we got to spend with her, how incredible she was, which some people don't really know," Sparks said, before acknowledging that the film is likely to receive a significant boost at the box office, as well. "It's weird to say, because I don't want this to come off wrong in any way, but there are a lot of people who are gonna go see it because it's her last film and because it was the last thing that she did. I think that's going to be amazing, too, because you have people who might not have gone before who are gonna go see it and are gonna get to see how incredible she was."

Email: Sophie.Schillaci@thr.com; Twitter: @SophieSchillaci