Aiming at shortening the time of building model and improving the effect of updating model in traditional codebook algorithm,with the thoughts of model establishment and updating from visual background extractor (ViBe),a new moving object detection algorithm called random codebook is put forward in this paper.Based on the traditional codebook algorithm,a new codebook model on YUV color space is raised to reduce the computational complexity,and a new codebook training method is proposed based on pi xels selected randomly in the field of space domain from the first image to shorten the model-building time and impro ve the cleanliness of it.Besides, in order to improve the adaptability of the background model to complex scenes, a random updating strategy for the codebook is also used in the new algorithm.Finally,two comparative experim ents are done with typical algorithms.And the experimental results show that the improved algorithm could not only adapt quickly to the changes of scenes but also greatly improve the det e ction accuracy,dynamic adaptability and real-time performance.