Is there any code to add a float or integer value with a raster layer? I can easily do mathematical operations between two raster data. But I am unable to do the same between float or integer number and raster layer. For example if want to execute (256-band3), how can I execute?
If you have a copy of FME then you can use the RasterExpressionEvaluator transformer.
In this case (256-band3) the expression would be simply:
(FME labels bands as 0,1,2 rather than 1,2,3).
The nice thing is that it also allows IF statements, so you can work up to complex statements like:
if ((A+A+A)==0, 255, A)
This page on FMEpedia has a bunch of examples.