Monday, January 18, 2021
Home Lead Story Frequency Analysis: Researchers Use New Method to Spot Deepfake Images, Videos

Frequency Analysis: Researchers Use New Method to Spot Deepfake Images, Videos

Scientists have put machines on job to spot deepfake images, videos

Deepfakes are becoming more authentic owing to the interaction of two computer algorithms to create perfect ‘fake’ images and videos, and humans are simply unable to gauge which is real or not.

Researchers now propose a new method called ‘frequency analysis’ that can efficiently expose fake images created by computer algorithms.

“In the era of fake news, it can be a problem if users don’t have the ability to distinguish computer-generated images from originals,” said Professor Thorsten Holz from the Chair for Systems Security at Ruhr-Universitat Bochum in Germany.

Follow NewsGram on LinkedIn to know what’s happening around the world.

Deepfake images are generated with the help of computer models, so-called Generative Adversarial Networks (GANs).

Two algorithms work together in these networks: the first algorithm creates random images based on certain input data. The second algorithm needs to decide whether the image is a fake or not.

Scientists put machines on job to spot deepfake images, videos
The image of a man generated by StyleGAN, an generative adversarial network (GAN). The person in this photo does not exist, but is generated by an artificial intelligence based on an analysis of portraits. Wikimedia Commons

If the image is found to be a fake, the second algorithm gives the first algorithm the command to revise the image – until it no longer recognises it as a fake.

In recent years, this technique has helped make deepfake images more and more authentic.

Deepfakes are video forgeries that make people appear to be saying things they never did, like the popular forged videos of Facebook CEO Zuckerberg and that of US House Speaker Nancy Pelosi that went viral last year.

To date, deepfakes have been analysed using complex statistical methods.

The Bochum group chose a different approach by converting the images into the frequency domain using the discrete “cosine transform”.

The generated image is thus expressed as the sum of many different cosine functions. Natural images consist mainly of low-frequency functions.

The analysis has shown that images generated by GANs exhibit artefacts in the high-frequency range.

Scientists put machines on job to spot deepfake images, videos
The girl in this image does not exist. This face was constructed by a GAN program which artefacts in the high-frequency range. Wikimedia Commons

For example, a typical grid structure emerges in the frequency representation of fake images.

Also Read: It is an Extraordinary Time for us to Educate Ourselves: Dia Mirza

“Our experiments showed that these artefacts do not only occur in GAN generated images. They are a structural problem of all deep learning algorithms,” explained Joel Frank.

“We assume that the artefacts described in our study will always tell us whether the image is a deepfake image created by machine learning,” Frank said, adding that frequency analysis is, therefore, an effective way to automatically recognise computer-generated images.

The team presented their work at the virtual International Conference on Machine Learning (ICML) this week. (IANS)



Most Popular

Here’s Why People Experience Abdominal Pain While Consuming Certain Foods!

Researchers have identified the biological mechanism that explains why some people experience abdominal pain when they eat certain foods. According to the researchers, up to...

Is Tandav Web Series Promoting Religious Flares? Know The Reason Behind Controversy!

The Information and Broadcasting Ministry has issued notice to Amazon Prime, seeking its response to the complaints against its web series 'Tandav' starring Saif...

Akshay Oberoi: This Profession Can Knock You Down Multiple Times

Akshay Oberoi has been a part of Bollywood for almost a decade now. He agrees that the acting profession is difficult and can knock...

B-Town Actress Kangana Ranaut Shares Awful Thing About Nepotism

Actress Kangana Ranaut says after nepotism, the most awful thing about being an actor is going through a night shift. "Apart from nepotism and movie...

Cure. Fit Acquires Digital Fitness Company Onyx

Health and fitness startup Cure. fit on Monday announced it has acquired Onyx, a US-based fitness company that is building the world's smartest digital...

5 Instagram Tools One Should Be Using In 2021

BY OUTREACH REVIEWS We are living in the digital era where the internet is rapidly taking over our lives and influencing the way we live. Social...

Save Planet, Turn Off Your Camera During Virtual Call

Turning off your camera during a virtual meeting can do a lot to reduce your carbon footprint, a new study suggests. The study, published...

A Musical Tribute To The Valor And Brave Indian soldiers

In the run-up to this year's Republic Day, music aficionados can gear up for a musical tribute to the valor and courage of the...

Recent Comments