The funeral portraits may hold more significant meanings for the loved ones of these elders.

"My grandpa didn't leave any photos behind. When we try to reminisce, his face starts to fade in our memories as years pass by. We need a clear and decent image of him to remember," Wu said.

In his social media posts, Wu managed to retrieve a photo he took with his grandfather years ago. When his grandmother glanced at it, she sighed: "All these years have passed. I have grown old, but he still looks young in this picture."

While taking these portraits, Wu also recorded some behind-the-scenes moments. For example, the cousin of Wu's grandmother and her husband have been married for over 50 years, and Wu captured them helping each other with their hair and clothing while getting ready for the photo shoot.

"For many elders, they neither have the concept of romance nor express sentiments such as saying 'I love you' or sending flowers," Wu recalled. "But that moment of casual tenderness was truly romantic."

Wu also made these moments into videos and posted them online. They have now exceeded 4 million views on the video-sharing platform Bilibili. Some nonprofit organizations even reached out to Wu and asked him to take photos for elders of the Yi ethnic group in Southwest China's Yunnan province.