Conversion of a colour image to an IR-like effect.

[Cluster]

I've tried manipulating a few RBG image to get an effect like near Infrared. I can't get anywhere near it.
I recall using an image editor (years ago) that had a straight conversion option. It worked well enough for what I wanted, but I can't remember what image editor it was.
It would have been a Linux editor... anyone got any idea of something similar?

(I'm a beginner in Darktable, Rawtherapy and GIMP.)

 

[ancient_mariner]

I would explore colour channel swapping in GIMP.

 

[Cluster]

I have found a Styles "plug-in" IR module/converter for Darktable. Installed and tried on a couple of colour images, it's nothing like what I hoped for. It gives a high contrast B&W image.
I'll have a dig into my archives, maybe the metadata will show what editor was used (if it was the last to do anything to the image).

 

[ancient_mariner]

Help me understand - you want your ordinary colour images to look like 'real' false-colour IR images?
IR image-2714 by Toni Ertl, on Flickr

Or you want your colour images processed to appear a little like IR images?
Fuerteventura redux X by Toni Ertl, on Flickr

 

[Cluster]

The latter... I want to use a normal colour image to produce an IR-like B&W image. I have a couple of cameras converted to IR (one 720 & one full) which i can use, but most times, I have not planned on IR photography and have taken only a regular camera (plus a D80 I have is pretty heavy). I recall making a few B&W from colour files and I felt that they looked pretty good..

EDIT: Well, I shows what time can do to (my) memory. I found both the colour image and the IR B&W image. When I desaturated the colour image it didn't look very different to the "IR" converted image!.. chasing ghosts..