a0.gmz stores a 32-bit linear float image of One of if not my best Photograph. exported by PhotoFlow. Although slow, I normally don’t have any issues processing it. The error happened when I did colormap 0, which I rarely use on large images. Not easy for me to test. It takes an inordinate amount of time to run this command. I tried it on another similar file just now. It hasn’t stopped running and I can’t keep it running, so I aborted it. Hope you find a solution. bad_alloc doesn’t sound good.