[FWTools] NULL or background values during merges/warp

Shaun Kolomeitz Shaun.Kolomeitz at epa.qld.gov.au
Sun Jan 21 23:52:06 EST 2007

Dear FWTools,

I am wondering if there is a way to specify a NULL value when merging
images which have those annoying black strips on their edges ?
In the past I have clipped images to remove this "strip", but when you
are processing 500+ images this gets way too time intensive.
Ideally I'd like the merge process to ignore band values of 0,0,0
(especially around the edge). I realise this is probably going to
exclude some pixels which are actually "black" as opposed to being
"NULL", but I can't see any other way around it.

I can demonstrate this more graphically if required.

Kind regards,


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