摘要
为了实现花菇的自动分选,设计了一种基于机器视觉的花菇分选系统,并提出了相应的算法。针对花菇分选中花菇的菇柄长度、形状类别和菌盖面积这3个重要分选指标,提出了一种曲线结构特征分析的分选方法。跟踪花菇边界并计算曲率,根据边界上点运动变化模式判断曲线凹凸性,利用曲线类半径识别并定位菇柄的位置。使用极坐标意义下的线性插值重建去除菇柄的菌盖边界曲线,在重建曲线基础上提取9种形状特征参数和1个大小特征参数,利用主成分分析法从9个形状参数中提取相应的3个主分量,以这3个主分量作为输入,构建K近邻分类器作为形状分选模型。结合花菇的菇柄识别情况、形状等级和大小等级共同判定花菇的最终等级。试验表明,菇柄识别正确率为91.4%,且菇柄识别能显著提高形状分选的准确率,最终形状分选正确识别率可达95.6%,花菇等级分选正确率为92.2%。
In order to grade of shiitake mushroom, grading system of a shiitake mushroom with the practical corresponding algorithm was developed based on machine vision. According to length of stem, shape sorting of shiitake mushroom, and method of area, identification algorithm based on curve reconstruction was presented. With shiitake mushroom as a case study, the boundary is tracked and the curvature is calculated by tracking the boundary, and then the concave-convex quality of boundary can be distinguished with the curvature, then the possible shiitake mushroom region is found and the actual position of the shiitake mushroom can be found with the class radius of curve. Linear interpolation of edge curve of the shiitake mushroom handle removed region is performed under polar coordinate, and the shape of pileus is reconstructed, then nine shape parameters and one parameter of size are distracted based on the curve reconstructed. The shape parameters are reduced to 3 with principal component analysis. The minimum distance classifier can be constructed as the sorting model with the 3 main shape parameters as input. Considering with the identification of stem of shiitake mushroom, the final identification of the shiitake is determined on both of the shape and the size classification. Experiments shows that the accuracy of stem identification is 91.4% , and the accuracy of shape sorting can be greatly improved by identification of stem of shiitake mushroom; the precision ratio of shiitake mushroom shape grading is 95.6% ,while the accuracy of shiitake mushroom grading can reach to 92.2%.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2014年第1期281-287,共7页
Transactions of the Chinese Society for Agricultural Machinery
基金
中央高校基本科研业务费专项资金资助项目(2010JC006)
华中农业大学研究生科技创新专项资助项目(2012SC19)
关键词
花菇
机器视觉
分选
特征提取
Shiitake mushroom Machine vision Sorting Feature extraction
