Plant leaf tooth feature extraction

Abstract

Leaf tooth can indicate several systematically informative features and is extremely useful for circumscribing fossil leaf taxa. Moreover, it can help discriminate species or even higher taxa accurately. Previous studies extract features that are not strictly defined in botany; therefore, a uniform standard to compare the accuracies of various feature extraction methods cannot be used. For efficient and automatic retrieval of plant leaves from a leaf database, in this study, we propose an image-based description and measurement of leaf teeth by referring to the leaf structure classification system in botany. First, image preprocessing is carried out to obtain a binary map of plant leaves. Then, corner detection based on the curvature scale-space (CSS) algorithm is used to extract the inflection point from the edges; next, the leaf tooth apex is extracted by screening the convex points; then, according to the definition of the leaf structure, the characteristics of the leaf teeth are described and measured in terms of number of orders of teeth, tooth spacing, number of teeth, sinus shape, and tooth shape. In this manner, data extracted from the algorithm can not only be used to classify plants, but also provide scientific and standardized data to understand the history of plant evolution. Finally, to verify the effectiveness of the extraction method, we use leaf tooth features and simple linear discriminant analysis to classify leaves; the results show that the proposed method achieves high accuracy as compared to other methods.

Optimization method for rough-finish milling allowance based on depth control of milling affected layer

“…This proposed method can be easily extended to other machining scenarios and can be used as guidance of process planning for meeting various engineering demands. Tian et al [6,7] carried out the process allowance distribution optimization in the semi-finishing stage based on the eigenvalue sensitivity method. This method can effectively improve the stability of thin-walled workpiece processing.…”