Digital information of the Cave No. 148 at the Mogao Grottoes in Dunhuang, northwest China's Gansu province, is being collected. (Photo from the website of the Dunhuang Academy)

China's Dunhuang Academy, which administers the Mogao Grottoes, a 1,600-year-old UNESCO World Heritage site in northwest China's Gansu province, has built a rich base of cultural resources by developing a complete system that integrates digital cultural heritage collection, processing, storage, and display technologies. This has significantly promoted the innovative transformation and development of fine traditional Chinese culture.

For instance, it offers high-definition panoramic tours of 30 caves on digital platforms; its mini program on the social media platform WeChat has seen a total of over 200 million online interactions. Besides, it has launched an official virtual cartoon figure named Jiayao, which originated from a half-woman, half-bird creature on millennia-old murals.

The Dunhuang Academy employs a map app that uses augmented reality for navigation in the caves. When visitors' phone cameras are pointed to certain directions or at certain objects in the caves, the app overlays information and sometimes virtual Buddhist characters on the screen, such as the Deer of Nine Colors, whose story was discovered as cave paintings in the Mogao Grottoes.

Visitors can pose for pictures with these virtual characters and have the pictures sent to their phones through WeChat, said Zhang Ruizhi, a tour guide at the Dunhuang Academy.

The massive digital resources of the Mogao Grottoes, when assisted by spatial orientation and online-merge-offline technologies, can create a digital twin of the World Heritage site, which marks a new attempt that enables visitors to watch the grottoes outside of them, noted Yu Tianxiu, director of the academy's cultural relics digitalization institute.

It's not easy to move the cultural relics at the Mogao Grottoes to the digital world.

An aerial photo of the Mogao Grottoes in Dunhuang, northwest China's Gansu province. (Photo by Wang Binyin/People's Daily Online)

"It calls for well-designed plans for 3D image collection and science-based verification of these plans according to the sizes, shapes, and preservation of the caves as well as the difficulty of 3D scanning. Then we need to use customized tracks and filming vehicles to take photos. In the end, we put together thousands of images into one complete piece," Yu explained.

The "Incredible Buddhist Grottoes" is an outstanding result of a Digital Dunhuang project. It is the world's first ultra high definition digital full dome film themed with grotto art. The 20-minute 8K video shows every detail of the seven caves of the highest artistic value at the Mogao Grottoes. Watching the film is like being in the caves, as every mural or painted sculpture shown on the screen is exactly the same as what's at the Mogao Grottoes.

"Apart from the 'Incredible Buddhist Grottoes,' we also produced another film titled 'Thousand-year Mogao,'" said 85-year-old honorary president Fan Jinshi of the Dunhuang Academy.

According to her, visitors are more likely to have better experiences visiting the caves after watching the two films.

Today, 1:1 digital replicas of the caves at the Mogao Grottoes are presented at online exhibitions, bringing faraway thousand-year-old treasures right in front of people's eyes.

Visitors can explore the caves wearing a virtual reality headset, browse ultra high definition pictures of the World Heritage Site with just clicks on the mouse, or enjoy a 720-degree panoramic tour of the 30 caves at the Mogao Grottoes on digital platforms.

Su Bomin, president of the Dunhuang Academy, told People's Daily that the academy has constantly strengthened its capability of technological innovation and set up a digital record for every cave, mural, and painted sculpture.

"We aim to permanently preserve the information of the murals and painted sculptures at the Mogao Grottoes," Su said.

As of the end of 2022, the Dunhuang Academy had collected digital information of 289 caves, processed images for 178 of them, and rebuilt 45 painted sculptures, 140 caves, and 7 heritage sites in the digital world. Besides, it had also produced panoramic shows for 162 caves and digitalized over 50,000 photographic films.

All the data have been compiled into digital files according to specifications, which creates more possibilities for academic research and further utilization.

Du Juan, who's in charge of the Dunhuang Academy's media center, told People's Daily that the official virtual cartoon figure Jiayao of the Mogao Grottoes has dynamic facial expressions, and her hair, clothes, and accessories can even sway with the "wind."

Su said Jiayao, who can guide online tourists, host livestream sessions, and perform the Dunhuang dance, will better introduce the culture of Dunhuang to Chinese and foreign visitors.

At the end of 2022, the world’s first blockchain-based open sharing platform for cultural heritage "e-Dunhuang" was launched. It opens over 6,500 high-definition digital files from grotto sites including the Mogao Grottoes and literature at the Dunhuang Library Cave, offering fantastic contents for scholars, cultural enthusiasts, and artists.