SAN FRANCISCO, California: A wave of Ghibli-inspired AI artwork has sent ChatGPT usage skyrocketing, as users have embraced the image-generation feature to create illustrations that mimic the signature style of the beloved Japanese animation studio.

OpenAI's chatbot recorded a surge in traffic last week, with average weekly active users topping 150 million for the first time in 2024, according to market research firm Similarweb. The viral trend drew inspiration from Studio Ghibli's hand-drawn aesthetic, as seen in classics like Spirited Away and My Neighbor Totoro, and led to millions of people sharing AI-generated art online.

"We added one million users in the last hour," OpenAI CEO Sam Altman posted on X, referencing a milestone that once took five days when ChatGPT first launched.

The surge followed updates to OpenAI's GPT-4o model, which expanded the platform's image generation capabilities. Data from SensorTower confirmed that the platform hit all-time highs in app downloads, in-app revenue, and active users during the week.

Compared to the previous week, downloads rose by 11 percent, weekly active users grew by 5 percent, and in-app purchase revenue jumped by 6 percent.

But the sudden popularity came with a cost. OpenAI's servers were strained by the demand, resulting in limited availability of the image tool and a series of minor outages.

"We are getting things under control, but you should expect new releases from OpenAI to be delayed, stuff to break, and for service to sometimes be slow as we deal with capacity challenges," Altman warned.

The popularity of the so-called "Ghibli effect" has also raised questions about copyright infringement.

"The legal landscape of AI-generated images mimicking Studio Ghibli's distinctive style is an uncertain terrain. Copyright law has generally protected only specific expressions rather than artistic styles themselves," said Evan Brown, partner at law firm Neal & McDevitt.

OpenAI has not commented on how it trained the model or addressed the legal risks tied to replicating Ghibli's visual language.

Studio Ghibli co-founder Hayao Miyazaki's past remarks also resurfaced amid the debate: "I am utterly disgusted. I would never wish to incorporate this technology into my work at all."