特征可视化方法具有简化复杂流场表示、突出流场特征的特点，在复杂流场可视化中具有重要作用。传统特征可视化方法通常采用自动化提取方法，不能有效结合用户知识与经验，无法满足用户的交互需求。考虑复杂流场特征区域精确界定的困难，提出一种交互式模糊特征提取算法，实现了对流场特征的交互式提取与可视化。首先基于模糊理论，给出了3维流场特征的模糊描述模型，然后交互式模糊特征提取算法与实现。应用所开发的交互式模糊特征提取可视化系统证明，它不仅可以充分发挥用户优势，有效提取数据特征，适时获取对象特征，还可以有效表现数据集客观不确定性的本质。

Feature visualization plays an important role in visualization of complicated flows because it can highlight the feature of the flows with a simplified representation. Traditional feature visualization methods usually employ the semi-automatic technique. The user’s interactive requirements can hardly to be met due to the weakness for integrating the user’s knowledge and experience. Because of the difficulties with extracting the strict confines of a feature, this paper presents an interactive fuzzy feature extraction algorithm, and has realized interactive extraction and visualization of the flow features. Firstly, construct a model describing the flow features based on the fuzzy theory. Secondly, we implement the algorithm based on the syntax standard. We have developed a visualization system based on the presented interactive fuzzy feature extraction method. The experimental results show that our method can not only make full use of the knowledge and experience of the user to extract the features of the data and the objects on demand but also reflect the uncertainty nature of the data.