The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B7. Beijing 2008 
(c) Wavelet algorithm image (d) Our algorithm image (c) Wavelet algorithm image (d) Our algorithm image 
Figure 1 First fusion experiment of multifocus image 
Figure 2 Second fusion experiment of multifocus image 
We compute the average gradients of the two groups of images, 
the results are shows as Table 1. 
Left 
focus 
Right 
focus 
Wavelet 
Our 
method 
Experiment 1 
Experiment 2 
2.5166 
2.6161 
3.8978 
2.8508 
4.2799 
2.4947 
5.0357 
3.2018 
Table 1 Comparison of image average gradient 
From Table 1, we can notice that our algorithm has higher 
average gradient than wavelet method and the defocused images, 
which demonstrators that our algorithm is valid and performs 
well. 
5. CONCLUSION 
There are two types of multifocus image fusion methods, the 
spatial domain and the frequency domain. However, they both 
have respective disadvantages. This paper proposed a spatial 
domain and frequency domain integrated approach to fusion 
multifocus image. Two groups of different focus images were 
performed to evaluate the performance of our method. 
Experimental results showed that our algorithm can provide 
better performance than the wavelet method from both visual 
perception and quantitative analysis. 
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ACKNOWLEDGEMENTS 
This research is funded by China’s Special Technical D&R 
Project for Scientific Academies or Institutes, MOST and Basic 
Research Fund of Chinese Academy of Meteorological 
Sciences. 
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