using Iris+Zbuffer on Linux


Are there any Linux image editors/converters that are able to open the extended Iris image format (Iris+Zbuffer in Blender) and access the extra channels? I’ve tried GIMP, Cinepaint, XnView and a couple of others, but they either can’t open the file or the image is garbled and no extra channels are present.

Thanks in advance,


Maybe it’s too late for you, but this question comes out from time to time; for me it came tonight as I needed that extra channel to do some 3D-2D compositing and the various zblur/showzbuf sequence plugins didn’t work as expected…

Under linux you can use the ‘sgitopnm’ command, part of the ‘netpbm’ utilities, to extract the channels from an irix+zbuffer image (a.k.a. sgi image format).

sgitopnm -channel NUMBER image.sgi >image.NUMBER

where NUMBER is:
0 red
1 green
2 blue
3 alpha (useful, I didn’t know it was there!)
4 I haven’t figured out yet
5 sort of stratified zbuffer
6 zbuffer (very useful for compositing)
7 always gray (???)

I hope it will help any other linux user out there.


Better late then never :slight_smile:

Thanks a lot for your answer.