Question

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

(a) Composite filter

(b) M-derived filter

(c) Constant k filter

(d) None of the mentioned

The question was asked in homework.

This is a very interesting question from Unsharp Masking, High-boost filtering and Emphasis Filtering topic in section Intensity Transformations and Spatial Filtering of Digital Image Processing

Answer 1

Correct choice is (a) Composite filter

To explain I would say: Unsharp masking can be implemented directly in frequency domain by using a composite filter: Hhp(u, v) = 1 – Hlp(u, v).