Convert drawimage colorimage to grayscale

[bzccat]

Hi,
Can someone please help me with the syntax so that drawimage produces grayscale images not color?

}def
/drawimage{
gsave
5 dict begin
4 index /width get
5 index /height get
6 -2 roll translate
4 -2 roll 1 index 1 index 0 eq exch 0 eq or
{pop pop 1 index 1 index}if scale
8 2 index 2 index [3 -1 roll 0 0 0 6 -1 roll sub 0 0]
5 -1 roll /source get dup resetfile false 3 colorimage
end
grestore
}def

[hvbtup]

How is this question related to Eclipse BIRT? At first glance, this looks like Postscript.
You should ask such questions in a Postscript forum.

[bzccat]

Yes sorry posted in wrong groups. I am using BIRT to generate postscript and posted here adn then realised my mistake after I had but couldn't see how to delete. I have an issue that we are using greyscale images in BIRT but when sent to colour printers it is using color ink to produce black instead of the black toner.