Surveillance video coding with vehicle library

Inter prediction in video coding is very efficient to remove temporal redundancy. However, due to the limitation of short-term references, inter prediction can work only within a very short time interval. In surveillance videos, we observe that there are always similar vehicles passing through one static camera, but the time intervals of similar vehicles are usually several seconds to minutes, exceeding the time interval that short-term references can handle. To solve this problem, we propose to build a vehicle library, and to put high-quality copies of the similar vehicles into the vehicle library. During encoding, vehicles are detected from the current frame, and for each vehicle we can retrieve similar vehicles from the vehicle library, and take the retrieved vehicle picture as additional references for inter prediction. Preliminary experimental results show that the proposed vehicle library based method achieves as high as 10.1% bit-rate saving for surveillance video coding, compared to HEVC anchor.