Researchers demanded laws on victims of "revenge porn" be tightened after a study released Monday revealed abuses on a "mass-scale."

Furthermore, image-based abuse goes beyond "revenge porn," with sexual images used to "control, abuse and humiliate" people, said chief researcher Nicola Henry from the Royal Melbourne Institute of Technology (RMIT).

Scientists from the RMIT and Monash University focused on Australians between 16 and 49 years of age, basing their findings on 4,274 respondents to a nationwide online survey.

"One in five respondents in the survey reported that their sexual or nude images, or videos, were taken without their consent," Henry said.

Some 9 percent of respondents also reported "sextortion," threats that their pictures would be published.

Real numbers likely higher

Women and men were equally likely to be victimized through image-based abuse. At the same time, men were more likely to voluntarily share a nude or sexual image themselves. However, 12 percent of women declared that a stranger had taken a nude or sexual image of them without permission, compared to 5 percent of men.

Also, the new study found that Indigenous Australians and people with disabilities were especially vulnerable to this kind of mistreatment. Around half of respondents from both those groups reported image-based abuse. Also, people who identified as gay, lesbian, or bisexual were more likely to be targeted, as 36 percent from these groups reported abuse compared to 21 percent of heterosexuals.

The real numbers were likely higher than those determined by the survey, said Dr Asher Flynn from Monash University.

"Our survey only captured those victims who had become aware their images had been distributed, whereas some victims may never discover that their images have been taken and distributed, particularly if they are circulated on sites located on the dark web," she said.

Authorities 'struggling to catch up'

Researchers also looked into the mental toll of this abuse, with data showing that three quarters of people whose images were distributed experienced moderate to severe depression. Also, around two-thirds of people whose images were taken without consent reported similar symptoms.

The study showed that image-based abuse was far more common and affected a wider range of people than previously thought, RMIT's Nicola Henry said, according to an article on the university website.

"Image-based abuse has emerged so rapidly as an issue that inevitably our laws and policies are struggling to catch up," she said.

From mischief to federal crime

Authors of the study recommended a string of measures to combat this phenomenon, including making this kind of abuse a crime under federal telecommunications law, and establishing a dedicated helpline similar to a phone line already functioning in the UK.

Also, the reforms should include changing attitudes that "often blame the victims and play down the very real harm" of such behavior, says RMIT's Anastasia Powell.

According to the research, four out of five Australians agree that sharing nude or sexual images without permission should be a crime.

dj/rt (dpa, AFP)