1. In frequency domain terminology, which of the following is defined as “obtaining a highpass filtered image by subtracting from the given image a lowpass filtered version of itself”?

A. Emphasis filtering

B. Unsharp masking

C. Butterworth filtering

D. None of the mentioned

2. Which of the following is/ are a generalized form of unsharp masking?

A. Lowpass filtering

B. High-boost filtering

C. Emphasis filtering

D. All of the mentioned

3. High boost filtered image is expressed as f_{hb} = A f(x, y) – for(x, y), where f(x, y) is the input image, A is a constant, and f_{lp}(x, y) is the lowpass filtered version of f(x, y). Which of the following fact validates if A=1?

A. High-boost filtering reduces regular Highpass filtering

B. High-boost filtering reduces regular Lowpass filtering

C. All of the mentioned

D. None of the mentioned

4. High boost filtered image is expressed as f_{hb} = A f(x, y) – f_{lp}(x, y), where f(x, y) is the input image, A is a constant and f_{lp}(x, y) is the lowpass filtered version of f(x, y). Which of the following fact(s) validates if A increases past 1?

A. The contribution of the image itself becomes more dominant

B. The contribution of the highpass filtered version of the image becomes less dominant

C. All of the mentioned

D. None of the mentioned

5. If, F_{hp}(u, v)=F(u, v) – F_{lp}(u, v) and F_{lp}(u, v) = H_{lp}(u, v)F(u, v), where F(u, v) is the image in frequency domain with F_{hp}(u, v) its highpass filtered version, F_{lp}(u, v) its lowpass filtered component and H_{lp}(u, v) the transfer function of a lowpass filter. Then, unsharp masking can be implemented directly in the frequency domain by using a filter. Which of the following is the required filter?

A. H_{hp}(u, v) = H_{lp}(u, v)

B. H_{hp}(u, v) = 1 + H_{lp}(u, v)

C. H_{hp}(u, v) = – H_{lp}(u, v)

D. H_{hp}(u, v) = 1 – H_{lp}(u, v)

6. Unsharp masking can be implemented directly in the frequency domain by using a filter: H_{hp}(u, v) = 1 – H_{lp}(u, v), where H_{lp}(u, v) the transfer function of a lowpass filter. What kind of filter is H_{hp}(u, v)?

A. Composite filter

B. M-derived filter

C. Constant k filter

D. None of the mentioned

7. If unsharp masking can be implemented directly in the frequency domain by using a composite filter: H_{hp}(u, v) = 1 – H_{lp}(u, v), where H_{lp}(u, v) the transfer function of a lowpass filter. Then, the composite filter for High-boost filtering is __________

A. H_{hb}(u, v) = 1 – H_{hp}(u, v)

B. H_{hb}(u, v) = 1 + H_{hp}(u, v)

C. H_{hb}(u, v) = (A-1) – H_{hp}(u, v), A is a constant

D. H_{hb}(u, v) = (A-1) + H_{hp}(u, v), A is a constant

8. The frequency domain Laplacian is closer to which of the following mask?

A. Mask that excludes the diagonal neighbors

B. Mask that excludes neighbors in 4-adjacency

C. Mask that excludes neighbors in 8-adjacency

D. None of the mentioned

9. To accentuate the contribution to enhancement made by high-frequency components, which of the following method(s) should be more appropriate to apply?

A. Multiply the highpass filter by a constant

B. Add an offset to the highpass filter to prevent eliminating zero frequency term by filter

C. All of the mentioned combined and applied

D. None of the mentioned

10. A process that accentuates the contribution to enhancement made by high-frequency components, by multiplying the highpass filter by a constant and adding an offset to the highpass filter to prevent eliminating zero frequency term by the filter is known as _______

A. Unsharp masking

B. High-boost filtering

C. High-frequency emphasis

D. None of the mentioned

11. Which of the following is a transfer function of High-frequency emphasis {H_{hfe}(u, v)} for H_{hp}(u, v) being the highpass filtered version of an image?

A. H_{hfe}(u, v) = 1 – H_{hp}(u, v)

B. H_{hfe}(u, v) = a – H_{hp}(u, v), a≥0

C. H_{hfe}(u, v) = 1 – b H_{hp}(u, v), a≥0 and b>a

D. H_{hfe}(u, v) = a + b H_{hp}(u, v), a≥0 and b>a

12. The transfer function of High-frequency emphasis is given as H_{hfe}(u, v) = a + b H_{hp}(u, v), for H_{hp}(u, v) being the highpass filtered version of the image, a≥0 and b>a. for certain values of a and b it reduces to High-boost filtering. Which of the following is the required value?

A. a = (A-1) and b = 0,A is some constant

B. a = 0 and b = (A-1),A is some constant

C. a = 1 and b = 1

D. a = (A-1) and b =1,A is some constant

13. The transfer function of High frequency emphasis is given as: H_{hfe}(u, v) = a + b H_{hp}(u, v), for H_{hp}(u, v) being the highpass filtered version of image,a≥0 and b>a. What happens when b increases past 1?

A. The high frequency is emphasized

B. The low frequency is emphasized

C. All frequencies are emphasized

D. None of the mentioned

14. The transfer function of High frequency emphasis is given as: H_{hfe}(u, v) = a + b H_{hp}(u, v), for H_{hp}(u, v) being the highpass filtered version of image,a≥0 and b>a. When b increases past 1 the filtering process is specifically termed as__________

A. Unsharp masking

B. High-boost filtering

C. Emphasized filtering

D. None of the mentioned

15. Validate the statement “Because of High-frequency emphasis the gray-level tonality due to low-frequency components is not lost”.

A. True

B. False