A literature exhibition on the great Chinese ancient encyclopedia "Yongle Dadian" officially opened at the Lanzhou Museum in northwest China's Gansu Province on Tuesday, with some 70 pieces of material related to Lanzhou City in the classic for visitors to enjoy.

The "Yongle Dadian," commissioned by Emperor Yongle in 1403, collected more than 7,000 kinds of ancient Chinese books and records, covering literature, art, history, geography, philosophy and religion from the pre-Qin period (pre-221 B.C.) to the early Ming Dynasty (1368-1644).

With a total of 11,095 volumes and about 370 million characters, the "Yongle Dadian" was lauded as the "largest encyclopedia in the world" by the "Encyclopedia Britannica." In an effort to protect this world-renowned compilation, Emperor Jiajing of the Ming Dynasty ordered a re-recording of the classic. The copying work took five years to complete.

Despite meticulous protection, hand-copied books have been gradually lost over the long course of history. Today, only slightly over 400 volumes and a few fragments of the "Yongle Dadian" remain in the world, which is less than 4 percent of the original book.

To facilitate public dissemination and professional study of the great ancient encyclopedia, the Yongle Canon HD Images Database was released by the National Library of China in Beijing this February, which is freely accessible to the public for reference.

Using advanced technology, China has stepped up efforts to bring classic literature back to daily life. In 2022, Chinese central authorities issued a set of guidelines, promising greater efforts to digitize ancient books and encouraging libraries and archives to open their collections and digital resources to the public.

Ancient books are vital to China's efforts to carry on its cultural tradition, foster a Chinese ethos and enhance its cultural strength, said the guidelines.

The National Library of China Publishing House and the Research Center for Digital Humanities of Peking University jointly developed the Yongle Canon HD Images Database. Currently, it contains the content of 1,800 books from the National Library of China's collection of the "Yongle Dadian."

Based on the high-definition images, the database adopts GIS techniques and three-dimension restoration techniques to vividly display the binding and layout of the encyclopedia and the whereabouts of the existing volumes, according to Wei Chong, director of the National Library of China Publishing House.

Likewise, the "Complete Library in Four Sections," also known as "Siku Quanshu," a collection of Chinese classical works, is being digitized in Lanzhou, northwest China's Gansu Province.

Created in the Qing Dynasty (1644-1911), "Siku Quanshu" had seven duplicates, which were originally stored in seven imperial libraries located in Beijing, east China's Yangtze River Delta, and Shenyang in northeast China's Liaoning Province, among other locations. Currently, only three and a half duplicates remain.

The duplicate stored in the Wensu Pavilion library in Lanzhou, which was built in 2005, contains 36,315 volumes. It was initially stored in the Shenyang Imperial Palace, and moved to Lanzhou in the 1960s.

Significant efforts have been made to preserve this valuable copy. The local government has invested over 100 million yuan (about 14.57 million U.S. dollars) to continuously upgrade the library's conditions.

According to the library director Chen Jun, the library uses international-standard, temperature- and humidity-controlled storage with an average temperature of 12 degrees Celsius in January and a constant humidity of around 50 percent throughout the year.

To make the copy more accessible to the public, digitization efforts began in 2021 and are expected to be completed by 2024. Chen said the library plans to make the digitized resources of the ancient texts available for various purposes, such as research and development of cultural products, while ensuring copyright protection.

"This effort aims to promote the in-depth study of cultural relics and bring them closer to the general public," said Chen.

In south China's Guangdong Province, the Sun Yat-sen Library has finished digitizing several rare and precious editions of ancient books, 1,013 kinds of periodicals and 480 kinds of newspapers published before the founding of the People's Republic of China in 1949, among others.

To further improve the efficiency of using the library's collection, the library has carried out text data recognition and database-building work on about 20,000 microforms, enabling functions including full-text search and text copying, according to the deputy director of the library's digitization department Zhang Hongxin.

"Digital transformation is a trend of the times. Ancient books will be integrated with other cultural carriers in the digital space, allowing the public to understand the overall picture of our traditional culture through various digital forms," said Liang Jihong, director of the digital humanities research and education office at the Renmin University of China.