[Retracted] Level Set Image Feature Detection and Application in COVID-19 Image Feature Knowledge Detection

Figure 4

Filter variational level set algorithm split noise image.

(a) Initialization

(b) 80 iterations of evolution

(c) 140 iterations of evolution

(d) 200 iterations of evolution

(e) 260 iterations of evolution

(f) 320 iterations of evolution

(g) 400 iterations of evolution

(h) The segmentation result is denoised and smoothed

(i) Differential computing