# Neural Networks Examples
**URL:** https://discourse.itk.org/t/neural-networks-examples/1408
**Category:** Engineering
**Created:** [November 10, 2018, 11:19pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408 "2018-11-10T23:19:13Z")
**Posts on this page:** 14
**Page:** 1
### Author:  [@melrobin](https://discourse.itk.org/u/melrobin)
#### Post date: [November 10, 2018, 11:19pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/1 "2018-11-10T23:19:14Z")
I am trying to build the Neural Networks ITK example, but the compile fails because of a missing localMetaConfiguration.h. This requires the MetaIO package, but I do not see where this is an option to turn on in CMake, so maybe it is a default module (?)
The file is present in my build directory as ./Modules/ThirdParty/MetaIO/src/MetaIO/src/localMetaConfiguration.h
The class documentation shows ITKZLIB as a dependency, but this may be a default module as well.
Can anyone tell me how to enable these modules and get localMegaConfiguration.h so that I can complete the compile?
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### Author:  [@hjmjohnson](https://discourse.itk.org/u/hjmjohnson)
#### Post date: [November 11, 2018, 1:11am UTC](https://discourse.itk.org/t/neural-networks-examples/1408/2 "2018-11-11T01:11:14Z")
The ITK Neural Networks have not had any attention in many years. It would be great if you wanted to work on using them, but I will let you know that the last time I used them they were very sub-optimal performance. I think that everyone has abandoned using this implementation many years ago in favor of other more performant tools.
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### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [November 12, 2018, 4:12pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/3 "2018-11-12T16:12:33Z")
NeuralNetworks module does [depend](https://github.com/InsightSoftwareConsortium/ITKNeuralNetworks/blob/674d2201410399d3d7075ffc2a85bcc2e27a0275/itk-module.cmake#L18) on MetaIO, but MetaIO is part of the default modules and is already built by default.
Which example are you trying to build? And can you provide the `CMakeLists.txt` file of that example?
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### Author:  [@melrobin](https://discourse.itk.org/u/melrobin)
#### Post date: [November 12, 2018, 4:54pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/4 "2018-11-12T16:54:54Z")
I was wanting to build the code from the Insight Journal here: [http://insight-journal.org/browse/publication/93](http://insight-journal.org/browse/publication/93)
It might be a little bit old.
I am interested in seeing how ITK uses this technology and maybe there is some area of improvement.
Would a very simple CMakeLists.txt work?
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### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [November 12, 2018, 6:26pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/5 "2018-11-12T18:26:33Z")
I think the code from that Insight Journal article has already been integrated in `NeuralNetworks` module. A very simple `CMakeLists.txt` should work.
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### Author:  [@melrobin](https://discourse.itk.org/u/melrobin)
#### Post date: [November 13, 2018, 2:23pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/6 "2018-11-13T14:23:32Z")
The build still failed:
[melrobin@scorpion NN]$ make
Scanning dependencies of target NNTest
[50%] Building CXX object CMakeFiles/NNTest.dir/itkNNetIOTest.cxx.o
In file included from /home/melrobin/projects/NN/itkNNETFileReader.h:21:0,
from /home/melrobin/projects/NN/itkNNetIOTest.cxx:26:
/usr/include/ITK-5.0/metaTypes.h:12:10: fatal error: localMetaConfiguration.h: No such file or directory
#include “localMetaConfiguration.h”
^ ~~~~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.
make[2]: \*\*\* [CMakeFiles/NNTest.dir/build.make:63: CMakeFiles/NNTest.dir/itkNNetIOTest.cxx.o] Error 1
make[1]: \*\*\* [CMakeFiles/Makefile2:68: CMakeFiles/NNTest.dir/all] Error 2
make: \*\*\* [Makefile:84: all] Error 2
Here is my CMakeLists.txt:
[melrobin@scorpion NN]$ cat CMakeLists.txt
project(NeuralNetworkExamples)
cmake\_minimum\_required(VERSION 3.11)
find\_package(ITK REQUIRED)
add\_executable(NNTest itkNNetIOTest.cxx)
target\_link\_libraries(NNTest ${ITK\_LIBRARIES})
This file is generated, but maybe it is not installed in the correct area.
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### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [November 13, 2018, 3:36pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/7 "2018-11-13T15:36:18Z")
I was able to reproduce a problem with the code from IJ article. I get a slightly different error message:
```nohighlight
2>itkNNetIOTest.cxx
2>c:\users\dzenan\desktop\nn\itknnetfilereader.h(21): fatal error C1083: Cannot open include file: 'metaTypes.h': No such file or directory
```
You are building quite outdated code. Can you start off from [this](https://github.com/InsightSoftwareConsortium/ITKNeuralNetworks/blob/master/test/itkNeuralNetworkIOTest.cxx) source file instead? Enable `NeuralNetworks` remote module when building ITK in order to use it.
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### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [November 13, 2018, 3:56pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/8 "2018-11-13T15:56:42Z")
@rasoul Could you comment on [issue 11](https://github.com/InsightSoftwareConsortium/ITKNeuralNetworks/issues/11) after you have tried my suggestion?
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### Author:  [@melrobin](https://discourse.itk.org/u/melrobin)
#### Post date: [November 13, 2018, 4:07pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/9 "2018-11-13T16:07:30Z")
I’m sorry, but I put this response on Github instead of here:
I used the source here: [https://github.com/InsightSoftwareConsortium/ITKNeuralNetworks/blob/master/test/itkNeuralNetworkIOTest.cxx](https://github.com/InsightSoftwareConsortium/ITKNeuralNetworks/blob/master/test/itkNeuralNetworkIOTest.cxx)
instead of the source in the Insight Journal and now receive this error:
[melrobin@scorpion NN]$ make
Scanning dependencies of target NNTest
[50%] Building CXX object CMakeFiles/NNTest.dir/itkNeuralNetworkIOTest.cxx.o
In file included from /usr/include/ITK-5.0/itkNeuralNetworkFileReader.h:21:0,
from /home/melrobin/projects/NN/itkNeuralNetworkIOTest.cxx:19:
/usr/include/ITK-5.0/itkMetaImageIO.h:25:10: fatal error: metaObject.h: No such file or directory
#include “metaObject.h”
^ ~~~~~~~~~~~~~
compilation terminated.
make[2]: \*\*\* [CMakeFiles/NNTest.dir/build.make:63: CMakeFiles/NNTest.dir/itkNeuralNetworkIOTest.cxx.o] Error 1
make[1]: \*\*\* [CMakeFiles/Makefile2:68: CMakeFiles/NNTest.dir/all] Error 2
make: \*\*\* [Makefile:84: all] Error 2
Here is the CMakeLists.txt:
[melrobin@scorpion NN]$ cat CMakeLists.txt
project(NeuralNetworkExamples)
cmake\_minimum\_required(VERSION 3.11)
find\_package(ITK REQUIRED)
add\_executable(NNTest itkNeuralNetworkIOTest.cxx)
target\_link\_libraries(NNTest ${ITK\_LIBRARIES})
---
### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [November 13, 2018, 5:37pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/10 "2018-11-13T17:37:57Z")
You were missing `include(${ITK_USE_FILE})` in your `CMakeLists.txt`. I also needed to rename `itkNeuralNetworkIOTest` into `main` so it reads `int main(int argc,char* argv[])`. Here is the modified `CMakeLists.txt` which worked for me:
```auto
project(NeuralNetworkExamples)
cmake_minimum_required(VERSION 3.11)
find_package(ITK REQUIRED) # includes all ITK modules
#find_package(ITK REQUIRED COMPONENTS NeuralNetworks) # only includes listed modules and their dependencies
include(${ITK_USE_FILE})
add_executable(NNTest itkNeuralNetworkIOTest.cxx)
target_link_libraries(NNTest ${ITK_LIBRARIES})
```
---
### Author:  [@melrobin](https://discourse.itk.org/u/melrobin)
#### Post date: [November 13, 2018, 7:28pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/11 "2018-11-13T19:28:25Z")
I still get more or less the same error:
Scanning dependencies of target NNTest
[50%] Building CXX object CMakeFiles/NNTest.dir/itkNeuralNetworkIOTest.cxx.o
In file included from /usr/include/ITK-5.0/itkNeuralNetworkFileReader.h:21:0,
from /home/melrobin/projects/NN/itkNeuralNetworkIOTest.cxx:19:
/usr/include/ITK-5.0/itkMetaImageIO.h:25:10: fatal error: metaObject.h: No such file or directory
#include “metaObject.h”
^ ~~~~~~~~~~~~~
compilation terminated.
Where should metaObject.h be located? It appears that the MetaIO module is installed on my filesystem.
---
### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [November 13, 2018, 7:53pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/12 "2018-11-13T19:53:42Z")
This is the full path on my computer: `C:\Dev\ITK-git\Modules\ThirdParty\MetaIO\src\MetaIO\src\metaObject.h`
---
### Author:  [@melrobin](https://discourse.itk.org/u/melrobin)
#### Post date: [November 13, 2018, 10:58pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/13 "2018-11-13T22:58:39Z")
OK, where does this include file install to?
---
### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [November 14, 2018, 2:46pm UTC](https://discourse.itk.org/t/neural-networks-examples/1408/14 "2018-11-14T14:46:57Z")
Since it is in the src directory, probably nowhere. But on Windows, I don’t usually “install” ITK. Or on Linux. I have many ITK builds and I use them from build directories.
But we have probably discovered the source of your problems. **Bug:** NeuralNetworks don’t work correctly when installed. **Workaround:** don’t install it, use it from build directory.
Can you try the workaround? When configuring the example, point to the build directory, not the install directory.