Clips from the film were played for jurors during last year's trial of Dr. Conrad Murray, and even a defense attorney had to admit after watching unreleased footage that it didn't show the singer was impaired as Murray's team had hoped it would.
Sony Pictures Entertainment, which will distribute "Sparkle," declined to comment for this story or say whether it planned to release any footage of Houston's singing before the film's release.
The movie is a remake of a 1976 film written by Joel Schumaker and Rosenman, who said it became a cult favorite in the African-American community because of its complex characters during an era when so-called "blaxploitation" films focused on caricatures. The upcoming version co-stars Jordin Sparks, who rose to fame after winning the sixth season of "American Idol."
Sparks has not commented on Houston's death or her work with the singer on the film.
Jakes said Houston seemed to bring her own experiences to her role, in which she plays a singer trying to raise her children in the church so they avoid some of the mistakes she made during her career.
"Whitney brings to the character such a sense of knowingness," Jakes said.
By the time the film and soundtrack are released, some of the questions surrounding Houston's demise should be answered. Although investigators found some prescription medications in Houston's hotel room, officials are awaiting the results of toxicology tests before determining her cause of death.
Jakes said although he wasn't on set every day, he never saw Houston act unprofessionally.
"I certainly got the feeling she was trying to reposition her life and move forward with more focus and commitment to her faith," he said.
Although famous for her love songs, Houston began singing in church in New Jersey, where her mother, Grammy-winning gospel singer Cissy Houston, led a choir for many years.
Whitney Houston apparently felt comfortable returning to those roots in recent months. In addition to her work in "Sparkle," she sang "Yes, Jesus Loves Me" for an audience in Hollywood two days before her death. It was her final performance.