Whitney Houston’s family and friends describe her two sides in a new trailer for “Whitney.” The late singer was an iconic, amazingly gifted artist and performer, but she was also, as one of the doc’s interviewees puts it, “simple”: “She became Whitney Houston when it was time for her to get on stage,” she explains.

The divide between Houston the persona and Houston the person apparently weighed heavily on the six-time Grammy winner. “People think it’s so damn easy, and it’s not,” the “How Will I Know” songstress admits in archival footage.

Despite her personal turmoil, Houston’s beautiful voice and hard work cemented her a spot in music history. “You have three places to sing from: heart, mind, guts,” the singer’s mother, Cissy Houston, says in the trailer. “She learned them all.”

From Oscar-winning director Kevin Macdonald (“One Day in September”), “Whitney” will premiere at Cannes this month as part of the fest’s Midnight Screenings program. The doc hits theaters July 6.

Houston — who passed away in 2012 — was also the subject of last year’s Showtime documentary “Whitney: Can I Be Me.” “Whitney Houston,” “Whitney,” and “I’m Your Baby Tonight” are among her albums. Also an actress, Houston appeared in films such as “The Bodyguard,” “Sparkle,” and “Waiting to Exhale.”