In order to reduce the time of data filtering processing in the adaptive control system for autom-otive headlights, a method of amplitude-limiting median filter is proposed in this paper, which is based on sliding median filtering algorithm and can follow the variation trend of signals through a way of compen-sation. The algorithm needs two steps to complete filtering. The data is amplitude-limited with compensation first, and then processed through sliding median filtering. This algorithm combines real-time of sliding median filtering method with the validity to filter the random interference of amplitude-limited filtering method, and it could smooth the graph more accurately. The simulation and actual test results show that the improved filtering method can filter interference in the data in real time and the processing time can be reduced by 62% compared with that of the sliding median filtering method. In addition, it can get a better result and the lag time of speed signal is shorter. Moreover, it has a high real-time performance and satisfies the requirement of system design.
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