It was a very fast moving parade during rush hour. Besides, I am awkward with camera.
The following description is from Chinese folklore.

Wuchang refers to the escort or 'messenger' from the hell to transport a dead spirit from the hell to human world or vice versa. Basically, black and white are not due to the skin color or dressing color,
but rather they are representation of "Yin" and "Yang" (Dual forces in the world).
The black represents the Ying, while the white represents the Yang. This is similar to the Taiji diagram's black and white, which was based on the theory of Yin and Yang.

These are the Black Guard of Impermanence and White Guard of Impermanence- guards of Hell who are tasked to lead the spirits of the dead to the Underworld after death. The White Guard and the Black Guard are in charge of evil and good spirits respectively. They are worshipped in some Chinese temples and are colloquially referred to as "Great Grand-Elder" and "Second Grand Elder" respectively. They wear tall hats bearing Chinese characters and long robes which cover their entire bodies. They carry seals on their right hands and sticks with pieces of cloth on their left hands. In some tales, they appear during the Hungry Ghost Festival and reward the good by granting them pieces of gold. Statues of them in temples depict them as having ferocious snarls on their faces and with long red tongues sticking out to scare away evil spirits. They are called General Fan and General Xie or 7th master and 8th master. The White Wuchang is called "Xie Bi-an 謝必安". He is tall and skinny, and people call him "Chi-Ye 七爺 (7th Master)". The Black Wuchang is called "Fan Wu-jiu 范無救". He is short and fat, and people call him "Ba-Ye 八爺 (8th Master)". It was said that they were policemen in ancient time. During a prisoner transfer, they lost the prisoner, so they decided to split up to search for the prisoner. They planned to meet up under the Bridge. However, it was raining hard, and Xie Bi-an did not make it in time. Fan Wujiu was waiting under the Bridge for a long time and dared not leave. Eventually, Fan was drowned when the flood came. When Xie arrived and saw Fan was dead, he killed himself by hanging. Afterwards, the Heavenly Emperor saw that they were loyal to their duties and each other, so he appointed them gods to pick up dead people's spirits. There are supposed spiritual meanings about their names. "Xie Bi-an" means that one would be saved if one sacrifice to the Gods (Xie) or repent ("謝 Xie" 罪悔過). "Fan Wu-jiu" means if one committed sins (Fan zui "犯"罪), one would not be saved (Wu-jiu 無救).