[Insight-users] [ITK Community] Cost function value increases

[Hana Cherif]

Hello every body !


After execution of my images' registration program , using this components:

Regular Step Gradient Descent Optimizer,
Mean Squares Image  To Image Metric
Bspline interpolator

 I get this results::


Iteration number:     Cost function value


0                        2732.74
1                        2700.84
2                        2699.27
3                        2701.48
4                        2703.19
5                        2700
6                        2704.12
7                        2705.1
8                        2705.27
9                        2705.4
10                        2702.91
11                        2705.15
12                        2713.1
13                        2720.48
14                        2720
15                        2715.81
16                        2704.64
17                        2687.46
18                        2666.14
19                        2639.91
20                        2613.11
21                        2587.55
22                        2564.89
23                        2546.22

I use this parameters:
 optimizer->SetMaximumStepLength(0.10 );
 optimizer->SetMinimumStepLength( 0.05);
 optimizer->SetRelaxationFactor(0.5);

My question is : as you see i the results the value of the cost function
increases i want to know why can be the reason of this results please!! is
it just a probleme of parameters??

Thanks !
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