GEOFF BENNETT: There has been a sharp rise in so-called nudification technology.

These A.I.-powered tools can generate realistic fake images and videos that depict people as undressed, often without their knowledge or consent.

William Brangham reports on the growing concern over that technology and efforts to rein it in.

WILLIAM BRANGHAM: As the types and uses of this technology have grown, lawmakers at both the state and federal level have tried to draft laws to curtail it, but that has proven to be very difficult.

So, to help us understand this current landscape, we are joined by Kolina Koltai.

She's an investigative journalist for the news site Bellingcat, and she has been covering this issue closely.

Kolina, thank you so much for being here.

Could you help us just understand at first what these technologies are, what they do, and how they do it?

KOLINA KOLTAI, Bellingcat: Yes.

Thanks for having me here.

It is a little bit of a complicated topic, but essentially there are a range of services, apps, products out there from Web sites to an app you can download on your phone that allow you to essentially take a photo of someone's face and make a pornographic image and a now pornographic video of that person.

So, this might be, say, something as simple, where the term nudify comes from, is just removing the clothing digitally from a photo.

So it takes a real photo, removes the clothes, so the body is completely A.I.-generated, but you might also have technology nowadays that allows you to upload a face of someone from, like, imagine from Facebook or from Instagram, and it creates a whole brand-new image.

So the entire image is A.I.-generated based off that person.

So it makes a fairly convincing image or video that is sexual in nature based on that.

And there's even apps where you can face-swap.

So you might have a video clip and in some cases a pornographic video clip, and they upload of someone's face and it just essentially swaps that person's face onto another actress' body.

So while the face itself and the video itself might be real, they're from two different sources.

And these all kind of fall under the range of sort of what we might call, like, A.I.

nudification, A.I.

deepfake, A.I.-powered nonconsensual intimate imagery.

WILLIAM BRANGHAM: And how widespread are these technologies?

Who's making them and who is using them?

KOLINA KOLTAI: Yes, the technology is unfortunately incredibly widespread.

It's something that is a global issue, not just here in the U.S., but it's something that is definitely plaguing, say, like U.S.

high schools.

There is case after case of this kind of technology being spread about, being used by students.

I think some of the recent surveys have been done is that one -- about, I think, 50 percent of students are familiar with the technology, I have seen someone use the technology, something along those numbers.

And I think it just keeps on rising and rising.

And as far as the prevalence and availability of these kind of apps and technologies, you can find technology that does something similar available on the Google and app Play Store, which people have access to with their cell phones.

But we also then think about really name brand platforms like a Grok on X. So Grok is one of the platforms that is widely available.

Although not billed as a nudification or an aid fake app, it is an app that has been consistently used to generate nonconsensual intimate imagery of both adults and of minors.

But you also will see the prevalence of Web sites.

You might go to a particular Web site.

You don't have to do anything fancy or use a Google search platform or your search platform of choice to be able to put in something like a deepfake generator, a nudify app, something to remove clothes, things of that nature, and you find -- easily access to this.

And, particularly, these are cheap services to use.

I say that, with a dollar and five minutes, you can create, unfortunately, a really convincing nonconsensual intimate imagery of someone.

WILLIAM BRANGHAM: Can you talk a little bit about the efforts that have been made to try to curtail this?

I know there's been federal action, state-level action.

What kind of things have they done and how successful have those been?

KOLINA KOLTAI: Yes, we have seen some really great federal action that's taken place.

So if you're familiar with something that's called the TAKE IT DOWN Act, I believe we have actually seen now three people charged and arrested under that act.

But this is something that has been a big shift, because normally what we have seen is a lot of laws at the state level, so each states having to put in their own laws, either be toward revenge porn or synthetic imagery or nonconsensual imagery.

But the federal act -- or this federal act, the TAKE IT DOWN Act, puts them a little more widespread.

So it involves everything from criminalizing the creation of the images, so you will have actually deepfake laws that now apply across the country.

You will have it applied to platforms.

So platforms have 48 hours to take down the image once they have been notified and a variety of other things.

So you're also being -- penalizing people who are also using it to threaten.

So sometimes people will threaten, I will create this image of you, and that could even be counted under the TAKE IT DOWN Act.

So it is a big change in legislation.

In Minnesota, they recently passed a bill that actually prevents the technology itself.

So one thing that I have often will talk to and tell people is, one of the big gaps we have is that the technology itself didn't seem to be illegal.

So while creating the imagery is now considered, like, universally across the U.S.

against the law, the technology itself is now beginning to -- in August, the law will go into effect banning the technology of nudification apps.

WILLIAM BRANGHAM: Right, because I know a lot of your reporting has been looking at the financial incentives here.

And it seems like, if people are able to make money making these products and selling those products, that's the essential nut to crack here.

KOLINA KOLTAI: Yes, I often like to say I don't think the people who create the technology, make the Web sites, the apps and the services are necessarily always in it for the love of the game.

There are -- it's a little bit of a Whac-A-Mole situation.

In the kind of reporting that we do, we try to identify the people who are behind those Web sites, who are profiting off the Web sites of people paying for those services to get them shut down, because it's still very taboo topic to say that I own one of those Web sites, right?

So our reporting hopefully gets those shut down.

But, ultimately, at the end of the day, if people are no longer able to make money off of these sites, if they're not pulling in the, unfortunately, million -- multimillion-dollar industry that is nonessential deepfakes, I think they go on to something else.

We have seen this time and time again, particularly with a lot of people who are trying to get into the scene.

They're getting into it because they think they can make money from it.

So the harder we're able to crack down or a term I like to say is creating friction, we add friction to the process, the harder we make it for people to be able to access technology, to pay for that technology, for people to profit off that technology, we're going to be able to continue to try to nip this problem in the bud.

WILLIAM BRANGHAM: That is Kolina Koltai of Bellingcat.

Thank you so much for sharing your very troubling journalism with us.

KOLINA KOLTAI: Thank you for having me.