signal processing chapter for book

first of all sorry for cross posting
As I wrote some time ago we are trying to write a book proposal about the use of python/scipy/numpy in chemometrics and analytical chemistry. Since now I've received positive answer from eight authors and the only "missing" chapter is one about the use of python in digital signal processing (I've contacted some possible authors but since now they are busy).
The schedule will not too tight and the chapter doesnt' need to be too long.
Hope to hear from you soon