Fig. 1. Overall implementation process of the bright-field microscopic image sharpening method with improved anisotropy-guided filtering

Fig. 2. Local detail halo comparison of guided filtering and anisotropic guided filtering processing results. (a) Input image; (b) guided filtering result; (c) anisotropic guided filtering result; (d) saliency map of the guided filtering result; (e) saliency map of the anisotropy-guided filtering result

Fig. 3. Filtering processing results and saliency maps of AnisGF algorithm and proposed improved AnisGF algorithm. (a) (c) Processing results of AnisGF algorithm; (b) (d) saliency maps of Fig.3(a) and Fig.3(c); (e) (g) processing results of the proposed improved filtering; (f) (h) salient images of Fig.3(e) and Fig.3(g)

Fig. 4. Input image and its mask image. (a) Input image; (b) result of adding 100 grayscale value to the output mask

Fig. 5. Local results of a breast cancer cell image processed by different filtering unsharp mask algorithms. (a) Original bright field cell image; (b) MUM algorithm; (c) NUM algorithm; (d) BUM algorithm; (e) GFUM algorithm; (f) proposed algorithm

Fig. 6. Local results of a gastric cancer cell image processed by different filtering unsharp mask algorithms. (a) Original bright field cell image; (b) MUM algorithm; (c) NUM algorithm; (d) BUM algorithm; (e) GFUM algorithm; (f) proposed algorithm

Fig. 7. Local results of a cell image carrying Leishmania parasites processed by different filtering unsharp mask algorithms. (a) Original bright field cell image; (b) MUM algorithm; (c) NUM algorithm; (d) BUM algorithm; (e) GFUM algorithm; (f) proposed algorithm

Fig. 8. Partial results of objective experiments. (a) Images of cells carrying Leishmania parasites; (b)‒(d) images of cancer tissue slices

Fig. 9. Box plots of different evaluation indicators under the two datasets. (a) PSNR; (b) RMSE; (c) MS-SSIM

Fig. 10. Results of the ablation experiment. (a) Local area of the cell image carrying the Leishmania parasite; (b) result without edge preservation filtering; (c) result of anisotropy-guided filtering; (d) result of improved anisotropy-guided filtering