基于颜色及纹理特征的果蔬种类识别方法

Fruits and vegetables recognition based on color and texture features

为更好地表述果蔬图像纹理特征,提高智能果蔬识别系统识别准确性,提出一种颜色完全局部二值模式纹理特征提取算法。果蔬识别系统模型利用颜色完全局部二值模式提取图像纹理特征,利用HSV颜色直方图、外点/内点颜色直方图提取图像颜色特征,采用匹配得分融合算法将颜色和纹理特征相融合,采用最近邻分类器实现果蔬农产品分类。通过不同光照条件下和不同数量训练样本条件下的试验得出:颜色完全局部二值模式的果蔬图像纹理表述能力明显优于和差直方图等果蔬图像纹理操作子,识别率提升最小在5%以上,更适合果蔬分类;对比其他纹理特征提取算法,采用颜色完全局部二值模式与颜色特征进行融合时,识别率最优,时间开销约为1.1 s。该方法能够应用到智能果蔬识别系统中,提升系统识别准确性。

An intelligent fruit and vegetable recognition system utilizing image recognition can accurately and rapidly indentify different kinds of fruits and vegetables, which can improve supermarket and market sales efficiency. The feature extracting method is a very important issue in an intelligent fruit and vegetable recognition system. However, traditional fruit and vegetable recognition algorithms either ignore the texture feature of fruits and vegetables, or used texture features that couldn’t better represent the texture of fruit and vegetable images. In order to represent the texture feature of fruit and vegetable images better and improve the intelligent fruit and vegetable recognition system recognition rate, we proposed a novel texture feature extraction algorithms called color completed local binary pattern （CCLBP） in this paper. By extracting different kinds of color channels completed by a local binary pattern （CLBP） texture feature, the CCLBP constructed a new texture feature extraction algorithm. The Fruit and vegetable recognition system model uses CCLBP to extract an image texture feature, and uses a HSV color histogram and Border/interior pixel classification （BIC） color histogram to extract image color features. Then it uses a matching score fusion algorithm to fuse color and texture features, and finally, a nearest neighbor （NN） classifier is used to realize fruit and vegetable recognition. To verify the effectiveness of the algorithms, two different fruit and vegetable databases, called an interior database and an outdoor database, were constructed in this paper. The interior database acquired in a laboratory contains 13 kinds of fruits and vegetables, which is used to verify algorithms recognition performance under different kinds of illumination. The outdoor database acquired in the market contains 47 kinds of fruits and vegetables, which is used to verify algorithms recognition performance under a different number of training sets. A Fruit and vegetable recognition experiment under different kinds of illumination showed that, only by the texture feature indentifying the kinds of fruits and vegetables, the recognition rate of the CCLBP was 5%higher than the traditional fruit and vegetable texture features （such as Unser, TestA）, which means that the CCLBP is more suitable for fruit and vegetable recognition; besides, compared with other texture algorithms, the CCLBP fused with HSV color histogram and BIC color histogram can achieve a 73.93% highest mean recognition rate, which takes about 1.1 seconds indentifying an image. A fruit and vegetable recognition experiment under a different number of training sets had similar results as the experiment under different kinds of illumination. The recognition rate of the CCLBP was still higher than the traditional fruits and vegetables texture features. What’s more, the CCLBP fused with a HSV color histogram and a BIC color histogram can achieve 94.26%, the highest recognition rate. The experiments under different kinds of illumination and under different number of fruits and vegetables confirm the feasibility of our algorithm. Our algorithm can be used in intelligent fruit and vegetable recognition system, which improves the system accuracy rate.