Released for the United Nations International Day for the Elimination of Violence Against Women on Friday, Heard is shown sitting on a couch, as she emotionally speaks about her personal experience.

"How is this happening to me?" she asks, her voice breaking. "I'm strong. I'm smart. I'm not a victim."

Heard goes on to tell women who are in abusive relationships that talking to someone you trust is "the beginning of choosing yourself".

"It's the only way that people are going to feel comfortable in coming forward, raising their voices, standing up for themselves, is if we change the system in place that keeps them quiet," she says.

"Speak up. Speak up. Raise your voice. Your voice is the most powerful thing and we, together, as women standing shoulder to shoulder, cannot, and will not, any longer accept silence."

Heard filed for divorce from Depp in May, after a 15-month marriage.

Days later, she attended court with a bruised face to obtain a temporary restraining order against Depp, alleging he had repeatedly hit her and thrown a mobile phone at her during a fight.

The pair settled their divorce in August, a day before they were scheduled to attend court for a restraining order hearing centred on Heard's allegations.

Heard donated the entire $US7 million ($9 million) she received from the divorce settlement to the American Civil Liberties Union, to help its efforts to combat violence against women, and the Children's Hospital Los Angeles.