[Insight-users] Histogram-Size for Histogram-Metric

[Michael]

Hi,

when using one of the metric classes derived from 
HistogramImageToImageMetric, what is a reasonable size for the 
histogram? I've noticed that the default size is set to 256x256. If an 
image pixel is represented by an 8-bit value, this would mean we have a 
histogram bin for every intensity value pair that can occur. Is this 
reasonable in any case? I mean, if a pixel is coded using, say, 16 bits, 
should the histogram size be 2^16*2^16? This would obviously increase 
the computational complexity, since instead of iterateing through 
(2^8)^2 = 2^16 bins we now have to iterate through more that (2^16)^2 = 
2^32 > 4*10^9 bins in the EvaluateMeasure method.

Are there any hints that help to estimate a reasonable histogram size?

Thanks,

Michael