[Techtalk] Turning everything black

[David Sumbler]

I have a pdf file of some forms which consist of text with a few
monochrome images.  

I want to incorporate these into an OpenOffice text document, which will
eventually be printed off.  I converted the pages of the form to png
files, using Gimp, inserted them as background images into my document,
and set "wrap" to "through".

I was then able to fill in the responses required on the form using
OpenOffice.

This works fine, except that in the original blank form the text is
grey, and the images and the lines for the responses to the questions
are blue.  Since I have a black and white laser printer this does not
look very good, and the grey of the text is almost too pale to read.

I should like to modify these images so that everything apart from the
background is black.  I am sure this can probably be done very easily in
Gimp, or possibly even in OpenOffice itself.  But, try as I might, I
can't seem to get the result I want.

Can any one tell me how to do this?

David

-- 
David Sumbler <david at aeolia.co.uk>