Fig. 1. Flowchart of multi-focus fusion

Fig. 2. The output of the intermediate result of the original image quantization definition （there are 30 original images corresponding to the data）

Fig. 3. The influence of mask morphology corrosion factor size to the final result

Fig. 4. Intermediate result of the refined mask

Fig. 5. The result R of multi-focus fusion

Fig. 6. Part of the original image

Fig. 7. Multi focus fusion results of three experiments

Fig. 8. Partial enlarged view of Fig. 7（a）~（d）

Fig. 9. Quality score line chart