综合颜色和Contourlet直方图的图像检索方法

为提高图像检索性能，使用Harris彩色点提取器提取颜色特征点，设计一种基于颜色特征点的环形颜色直方图，在对图像进行Contourlet变换的基础上，提出Contourlet直方图的概念，改进其旋转不变性，并提取图像的纹理信息。仿真实验结果表明，该方法能够快速准确地检索彩色图像。

Image Retrieval Method Based on Color and Contourlet Histogram

Linear Discriminant Analysis(LDA) is one of the classical and popular methods used for feature extraction. In this paper, a new algorithm called Symmetrical LDA(SLDA) based on frontal facial symmetry is proposed. This algorithm is based on the theory of function decomposition and mirror symmetry. In the algorithm, mirror transform is introduced. Original face samples are decomposed into even symmetrical images and odd symmetrical ones. Even/odd symmetrical discriminant features are extracted from the corresponding samples respectively. Both theoretical analysis and experimental results demonstrate this algorithm not only enlarges the number of training samples, but also remarkably improves the recognition rates.