Fig. 1. Four examples of our test images: Lena blurred by 3×3 averaging mask with slight additive noise of STD=5 (top left), the same with heavy noise (STD=30) (top right), blurring by 9×9 mask with slight noise (bottom left), both heavy blurring and noise (bottom right).

Fig. 2. Energy of Laplacian M₅ calculated on Lena image for various amount of blurring and noise.

Fig. 3. Focus measure W calculated on Lena image for various amount of blurring and noise. Daubechies wavelet of 10 taps and the decomposition depth 1 was used.

Fig. 4. Focus measure W calculated on Lena image for various amount of blurring and noise. Daubechies wavelet of 10 taps and the decomposition depth 2 was used.

Fig. 5. Indoor scene: Focused image (top left), slight out-of-focus (top right), medium out-of-focus (bottom left), heavy out-of-focus (bottom right).

Fig. 6. Six consecutive sunspot images corrupted by variable blurring caused by atmospheric turbulence.

Table 1. Various focus measures calculated for the indoor images depicted in Fig. 5. Proportional values are used, 1 stands for the best focused image in the sequence

Table 2. Various focus measures calculated for the sunspot images in Fig. 6. Proportional values are used, 1 stands for the best image in the sequence