荧光造影图像序列的噪声滤波

通过对视网膜血流荧光造影图像分析， 将自适应加权 平均方法与顺序统计滤波器相结合， 构造了扩展自适应加权平均（EAWA）滤波器. EAWA滤 波器是一个灵活的滤波器模型， 它通过设计关键像素和权值分布函数， 以达到特定滤波效 果. 在此模型基础上， 针对荧光造影图像， 建立了高亮度保持（HIP）滤波器. 实验结果 表明， HIP滤波器不仅可以有效地滤波， 又可以保持高亮度点的亮度不被退化.

Noise Filtering for Fluorescein Angiogram Sequences

Intensity degradation is a common problem in noise filtering for fluorescein angiogram sequences. In this paper a new filter model, extended adaptive weighted averaging (EAWA) filter is proposed for the purpose of reducing noise of a fluorescein angiogram sequence by adopting the method of adaptive weighted averaging and the idea of order statistic filter. The EAWA filter is a flexible filter model, by which even a particular filter can be designed via defining pixel of interest (POI) and the sub-support of the filter according to some specified requirements. Based on the EAWA filter model, a fluorescein-angiogram-oriented filter, HIP filter is introduced to solve the problem of high-intensity preservation on filtering noise. The results of the contrast experiment show that the HIP filter has the features of frame-averaging, which can achieve noise suppression efficiently, and the features of high-intensity preservation for bright pixels, which can keep the intensities of bright pixels from degrading via distributing the weights adaptively according to the intensity of each pixel.