Does anyone know how to automate PDFpenPro to change a pdf from color to 1 bit black and white?

Hey all,

I receive frequently pdf files having huge file sizes. So far I manually reduce file sizes by using PDFpenPro to switch from color to 1 bit black and white (as in most instances b&w is sufficient for my needs).

Does anyone know how to automate PDFpenPro to change a pdf from color to 1 bit black and white?

Many thanks in advance.

Helge