[Insight-users] registration consistency

[Christoph Palm]

Hi Qing,

On Fri, 2007-07-20 at 14:32 +0000, qing xu wrote:
> Hi,
> 
> Does the same registration code with the same input always give the same 
> output?
> 

if you believe in the deterministic behavious of computers....

> I am doing a 3D registration for a dataset consisting of 50 volumes. I put 
> the registration code in a loop so that the registration can be done one by 
> one for each volume. However, the reults are much different from what I got 
> by processing one volume once a time. The only reason I can think of is that 
> running reigstration for too long would consume too much memory, so the 
> registration performance is affected. Is that possible?  Does anybody have 
> the same experience? Thanks in advance.
> 

Do you ensure setting all parameters to the original values?
If you, for instance, do hierarchic registration and change the step
width of the optimizer for each hierarchic level, then you certainly
have to reset them for the next loop. I have to own up to have
programmed such a bug in my own code :-(

Regards

Christoph