基于组合核函数SVM的说话人识别方法

Speaker recognition method based on combination of kernel functions of SVM

鉴于应用支持向量机进行说话人识别过度依赖于选择核函数的问题,提出一种基于组合核函数支持向量机(SVM)的说话人识别方法。对多项式核函数、径向基核函数进行线性加权,构建既具有全局核函数优点又具有局部核函数优点的组合核函数,并通过多重网格搜索调节权重系数使组合核函数适用于当前数据分布,确定组合核函数SVM的最优参数,实现对说话人的有效识别。对TIMIT数据集和含噪声数据集的仿真实验显示,基于组合核函数SVM的说话人识别性能明显优于单一的多项式核函数、径向基核函数和线性核函数。

In speaker recognition systems,if the original data distribution is unknown,the choice of inappropriate kernel functions will result in poor support vector machine（SVM） learning performance. Thus a speaker recognition method based on a multi-grid search of parameters and a combination of kernel functions is proposed in this paper. First,the method constructs a hybrid kernel function by linearly weighted polynomial and RBF kernels. Then it proposes a multi-grid search method to adjust the weights,and thus the hybrid kernel function can adapt to the current data distribution. Finally,a SVM classifier is trained to obtain the classification results. Simulation experiments on TIMIT datasets and noisy datasets show that the recognition performance of SVM classifiers using a combination of kernel functions is better than that using linear kernels,polynomial kernels,and RBF kernels.Therefore,the proposed method can effectively improve the performance of speaker recognition systems.