Face++ and Shangtang Technology mainly do face recognition algorithms. In the field of algorithms, these two companies are probably the best and the most famous in China. Of course, in addition to algorithms, they also make hardware, but only a small part.
Obi Zhongguang mainly focuses on hardware, and its products include Astra 3D induction cameras and other products. It is also the only manufacturer in China that can mass-produce 3D sensor cameras. At present, Obi-Zhongguang has reached cooperation with Ant Financial and KFC, and * * * launched 3D face-brushing payment equipment in KFC stores in Shenzhen and other places. Therefore, from the comprehensive strength of hardware, Obi Zhongguang is the leading one in China.
Finally, the three companies have a cooperative relationship. For example, OBI-Zhongguang will use the algorithms of face++ and Shang Tang, and the other two companies will also use OBI-Zhongguang's 3D sensor camera.
It is not easy to type so many words. I hope the subject can adopt the answer.