Feature enhancement: local maxima

In some applications, the presence of a `bump' in a signal may be more significant than its size. Then, it is imperative to display a local maximum, say, of the wavelet map by factoring out its magnitude, giving equal emphasis to molehills and mountains. The following algorithm has been implemented for generate Fig. 25:

1. identify a realistic size of an event on the wavelet map; for example, a rectangular box one-duration wide and allowing for limited ratio of durations in height, has been used.
2. identify all local maxima by placing a box around them and verifying that no larger values occur within the box.
3. within each box, normalize the values of the map by the local maximum.
4. threshold what is left to show the vicinity of each maximum.