Vehicle re-identification helps to determine whether a given vehicle has appeared in another camera. The technology is useful to automatically locate a certain vehicle in a network of cameras, mainly for surveillance applications. In practice, issues like variations in illumination changes, camera view angles, vehicle positions, etc. are the typical challenges that need to be solved by the vehicle re-identification technology.
In real-world practice, humans can treat this task in a progressive manner. For instance, if the security ofﬁcer needs to ﬁnd a suspect car in a city with large-scale video surveillance networks, appearance attributes such as models,types, and colors can be initially used to ﬁnd similar vehicles and reduce the search ﬁeld. Then, they can identify the targets precisely from the ﬁltered vehicles by matching the license plates, which can reduce the enormous workload. Meanwhile,they will search videos recorded by cameras from near to far positions and from close to distant time range. Therefore,the contextual information such as spatio temporal cues thus can decidedly assist in the search process.