[Insight-users] "Look-up-table" suggestion

[Martin Kavec]

Hi,

I am implementing a filter in which I need to perform  e^( pixelintensity). In 
the present implementation this is the major performance bottleneck (80%). I 
thought to generate a look-up-table of e^(x) function using a 
std::vector<...>, resized to cover the whole dynamic range of a PixelType. 
However, I am hitting a ceiling with this approach since this would be very 
memory-intensive solution for PixelType > 32 bits. 

Opinions, on what wold be the most sensible approach in generating the LUT and 
keeping the filter templated over the PixelType, would be appreciated.

Thanks,

Martin