外耳形状特征和内耳结构特征结合的人耳特征提取

针对人耳的生物特征提出了一种人耳的形状特征和结构特征相结合的识别方法. 首先提取外耳最长轴,即外耳轮廓边缘点的最长连线. 利用外耳长轴把外耳曲线分成两部分,用最小二乘法对这两段曲线分别进行多项式曲线拟合,拟合多项式函数的系数作为外耳特征向量. 同时长轴与内耳曲线的交点作为内耳特征点,特征点之间连线的长度与长轴长度的比值作为内耳特征向量. 长轴的相对不变性保证了特征向量具有缩放、平移和旋转不变性. 实验结果表明此方法在噪声情况下具有较强的鲁棒性.

Ear feature extraction combining the shape feature of outer ear with the structure feature of inner ear

A ear recognition method was proposed which combines the shape feature of outer ear contour with the structural feature of inner ear. The longest axis of auricle contour, which is the line crossing through the two points that have the longest distance on auricle contour, was firstly extracted after edge detection. Then least squares fitting polynomials were used to approximate the auricle curves. The coefficients of the polynomial functions were taken as the feature vector of outer ear contour. The longest axis intersects with the inner ear curves at several points. The ratio of the section length between the intersection points to the longest axis acts as the feature vector of inner ear. Owe to relevant invariability of the longest axis, the feature vectors extracted in the method are invariant to scale, parallel move and rotation. Experiment results prove robustness of this method.