针对现有车辆检测算法在实际复杂道路情况下对车辆有效检测率不高的问题,提出了融合多模式弱分类器,并以 AdaBoost-Bagging 集成为强分类器的车辆检测算法。结合判别式模型善于利用较多的特征形成较好决策边界和生成式模型善于利用较少的特征排除大量负样本的优点,以Haar 特征训练判别式弱分类器,以 HOG 特征训练生成式弱分类器,以 AdaBoost 算法为桥梁,采用泛化能力强的 Bagging 学习器集成算法得到 AdaBoost-Bagging 强分类器,利用 Caltech1999数据库和实际道路图像对检测算法进行了验证。验证结果表明:相比于单模式弱分类器,AdaBoost-Bagging 强分类器在分类能力和处理时间上均具有优越性,表现为较高的检测率与较低的误检率,分别为95.7%、0.00027%,每帧图像的检测时间较少,为25 ms;与传统级联 AdaBoost 分类器相比,AdaBoost-Bagging 强分类器虽然增加了12%的检测时间和30%的训练时间,但检测率提升了1.8%,误检率降低了0.00006%;本文算法的检测性能显著优于基于 Haar 特征的 AdaBoost 分类器算法、基于 HOG 特征的 SVM 分类器算法、基于 HOG 特征的 DPM 分类器算法,具有较佳的车辆检测效果。
Focusing on the problem that the vehicle detection rate of existed vehicle detection algorithms is lower in real complex road environment, a vehicle detection algorithm was proposed,in which multi-model weak classifiers were integrated into strong classifier by using AdaBoost-Bagging method.In the algorithm,discriminative model could generate a fine decision boundary by using more features,and generative model could eliminate negative examples by using fewer features.To combine the advantages of discriminative model and generative model, discriminative classifier with Haar feature and generative classifier with HOG feature were built. Combined with AdaBoost algorithm,AdaBoost-Bagging strong classifier was obtained by using Bagging algorithm that is an integrated learning algorithm with strong generalization ability. Vehicle detection algorithm was tested based on Caltech1999 dataset and real road images.Test result indicates that compared with sole mode weak classifier,AdaBoost-Bagging strong classifier maintains superiority in classification ability and processing time,its high detection rate and low false detection rate are 95.7%,0.000 27% respectively,and the detection time of each frame is 25 ms that is less.Compared with the traditional cascade AdaBoost classifier,the detection time of the AdaBoost-Bagging strong classifier increases 12%,the training time increases 30%,but the detection rate increases 1.8%,and the false detection rate decreases 0.000 06%.The proposed algorithm is better than other vehicle detection algorithms,including Haar feature-based AdaBoost classifier, HOG feature-based SVM classifier, HOG feature-based DPM classifier,and has better vehicle detection effect.3 tabs,8 figs,25 refs.