At the World Artificial Intelligence Conference in Shanghai this month, start-up founder Qu Dongqi showed off a video he had recently posted online. It displayed an old photograph of a woman with two toddlers. Then the photo sprang to life as the woman lifted the toddlers up in her arms and they laughed with surprise.

The video was created by A.I. technology from the Chinese internet company Kuaishou. The technology was reminiscent of a video generator, called Sora, that the American start-up OpenAI unveiled this year. But unlike Sora, it was available to the general public.

“My American friends still can’t use Sora,” Mr. Qu said. “But we already have better solutions here.”

While the United States has had a head start on A.I. development, China is catching up. In recent weeks, several Chinese companies have unveiled A.I. technologies that rival the leading American systems. And these technologies are already in the hands of consumers, businesses and independent software developers across the globe.

While many American companies are worried that A.I. technologies could accelerate the spread of disinformation or cause other serious harm, Chinese companies are more willing to release their technologies to consumers or even share the underlying software code with other businesses and software developers. This kind of sharing of computer code, called open source, allows others to more quickly build and distribute their own products using the same technologies.