[Insight-users] FW: Image Registration examples test results

Luis Ibanez luis . ibanez at kitware . com
Thu, 22 May 2003 13:30:41 -0400


Hi Xu,

You may expect all the multi-modality registrations to give slightly
different results due to the use of random sampling during the
evaluation of the mutual information metric. Apart from those, the
results should be pretty much the same as in the software guide.

Are the differences that you found larger than what you may expect
from numerical instability ?

Note that the examples for the software guide were all executed on
Linux. If you try this same code under windows you my find different
results due to the particular encoding of floating point numbers.
(40bits as opposed to the IEEE standard encoding). We have also found
that the numerical results are different if you run in Debug mode or
Release mode.

So...
a bit of numerical differences are to be expected in the results.

If you find large differences, that may indicate a bug in the code.

However, at this point the examples are verified nightly using a
regression testing system that you can check on the Dashboard.

Look for example at:
http://www . itk . org/Testing/Dashboard/20030522-0500-Nightly/TestDetail/__Examples_Registration_ImageRegistration1Test . html

When any of those tests fail, a difference image is generated
to help in the identification of the problem.


Please let us know if the differences that you encounter are
unreasonable large.


--------------

BTW in order to run tests whithout having to worry about passing
the parameters you can use the command line utility "ctest".
Just move to the binary directory of the examples and type:

                 ctest

you can also do

                 ctest ImageRegistration2Test

of even do regular expressions with

                 ctest -R Image*

you can see what test would be run, if you type

                 ctest -N

a short help about the ctest option can be displayed
with
                 ctest -h


--

   Regards


      Luis


---------------------
Xu, Yanjun wrote:
> Hi,
> 
>  
> 
> I just compiled the CVS version of Insight (May 20). Then I tested the 
> image registration examples. I couldn't run RegistrationExamples.exe, so 
> I run the registration example manually.  Some gave the exactly same 
> results as the ITK software guide. Some gave a little bit different 
> results. The following programs gave the same results.
> 
>  
> 
> ImageRegistration1.exe
> 
> ImageRegistration5.exe (the rotation only example)
> 
> ImageRegistration6.exe
> 
>  
> 
> ImageRegistration2.exe
> 
> ImageRegistration3.exe
> 
> ImageRegistration4.exe
> 
> ImageRegistration5.exe (the rotation and translation example)
> 
> ImageRegistration9.exe
> 
> MultiResImageRegistration1.exe
> 
> MultiResImageRegistration2.exe
> 
>  
> 
> Did I do something wrong? All the results are included in the email. 
> Could anyone help me with this? Thanks a lot.
> 
>  
> 
> Sincerely,
> 
> Yanjun
> 
>  
> 
> RegistrationExamples
> 
> Available tests:
> 
> ...
> 
> To run a test, enter the test number: 0
> 
> Missing Parameters
> 
> Usage: ITK test driver caught an unknown exception!!!
> 
>  
> 
>  
> 
> ImageRegistration2.exe result:
> 
> 0   0.296971   [-0.118028, -0.26582] ...
> 
>  [11.8759, 16.0134]199   0.633656   [14.1879, 17.3389]Result =
> 
>  Translation X = 14.1879
> 
>  Translation Y = 17.3389
> 
>  Iterations    = 200
> 
>  Metric value  = 0.633656
> 
>  
> 
> ImageRegistration3.exe result:
> 
> 0 = 4499.45 : [2.93041, 2.72262]
> 
> ...
> 
> 14 = 0.0418819 : [13.0215, 16.9997]
> 
> 15 = 0.204062 : [13.0059, 16.9999]
> 
> 16 = 0.0152613 : [12.9903, 17.0001]
> 
> Registration done !
> 
> Number of iterations = 18
> 
> Translation along X  = 12.9903
> 
> Translation along Y  = 17.0001
> 
> Optimal metric value = 0.0418586
> 
>  
> 
>  
> 
> ImageRegistration4.exe result:
> 
> 0   -0.513644   ...
> 
>  [13.1656, 16.8959]24   -1.15486   [13.1696, 16.8892]Result =
> 
>  Translation X = 13.1696
> 
>  Translation Y = 16.8892
> 
>  Iterations    = 26
> 
>  Metric value  = -1.15541
> 
>  
> 
> ImageRegistration5.exe result:
> 
> BrainProtonDensitySliceBorder20.png
> 
> BrainProtonDensitySliceR10X13Y17.png
> 
>  
> 
> 0   4224.31   [0.000171785, 110.5, 128.5, 0.0679716, 0.0733473...
> 
> [0.128943, 109.788, 129.06, 12.7059, 15.0696]Result =
> 
>  Angle (radians)   = 0.128943
> 
>  Angle (degrees)   = 7.3879
> 
>  Center X      = 109.788
> 
>  Center Y      = 129.06
> 
>  Translation X = 12.7059
> 
>  Translation Y = 15.0696
> 
>  Iterations    = 200
> 
>  Metric value  = 531.246
> 
>  
> 
> ImageRegistration9.exe:
> 
> Initial Transform Parameters
> 
> [1, 0, 0, 1, 123.423, 147.427, 12.2191, 15.836]
> 
> 0   1495.87    ...
> 
> [0.984931, -0.172931, 0.172476, 0.984878, 123.249, 147.12, 9.58722, 
> 17.9194]Result =
> 
>  Center X      = 123.249
> 
>  Center Y      = 147.12
> 
>  Translation X = 9.58722
> 
>  Translation Y = 17.9194
> 
>  Iterations    = 238
> 
>  Metric value  = 44.2647
> 
>  
> 
> MultiResImageRegistration1.exe:
> 
> 0   -0.778796 ...
> 
> 7   -1.25107   [12.9739, 17.018]8   -1.25242   [12.9509, 16.9969]Result =
> 
>  Translation X = 12.9509
> 
>  Translation Y = 16.9969
> 
>  Iterations    = 10
> 
>  Metric value  = -1.25138
> 
>  
> 
> MultiResImageRegistration2.exe:
> 
> 0   -0.778796  ...
> 
>  [1.00173, 0.00176814, 0.00182833, 1.00168, 12.5201, 16.3894]Result =
> 
>  Translation X = 12.5201
> 
>  Translation Y = 16.3894
> 
>  Iterations    = 7
> 
>  Metric value  = -1.25905
> 
>  
> 
>  
>