# GDCMSeriesFileNames fails to read folder with non ascii characters

**URL:** https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365
**Category:** Beginner Questions
**Created:** [October 31, 2019, 3:15pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365 "2019-10-31T15:15:14Z")
**Posts on this page:** 14
**Page:** 1

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### Author: ![antoine.letouzey](https://discourse.itk.org/user_avatar/discourse.itk.org/antoine.letouzey/32/57_2.png) [@antoine.letouzey](https://discourse.itk.org/u/antoine.letouzey)
#### Post date: [October 31, 2019, 3:15pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/1 "2019-10-31T15:15:14Z")

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I’m having trouble with code that worked just fine for years. I’m trying to open a DICOM dataset from Japan and my code cannot see any files of the series folder.

The code is (with placeholders for seriesUID and patient name :

```
... 
auto seriesUID = "1.2.3.4"; 
seriesPath = "F:\\Data\\Images\\Pat_MAXXXXXX MIXXXX=丸山 ___=マル___ \\Study_a1753f72\\Series_10b36a87";

typedef itk::ImageSeriesReader<itk::Image<short, 3>> t_ImageSeriesReader;
t_ImageSeriesReader::Pointer imageSeriesReader = t_ImageSeriesReader::New();

typedef itk::GDCMImageIO t_ImageIOType;
t_ImageIOType::Pointer imageIO = t_ImageIOType::New();
imageSeriesReader->SetImageIO(imageIO);

typedef itk::GDCMSeriesFileNames t_NamesGeneratorType;
t_NamesGeneratorType::Pointer namesGenerator = t_NamesGeneratorType::New();
namesGenerator->SetDirectory(seriesPath);
imageSeriesReader->ReleaseDataBeforeUpdateFlagOn();
imageSeriesReader->AbortGenerateDataOff();

imageSeriesReader->SetFileNames(namesGenerator->GetFileNames(seriesUID));
...

```

On the last line, GetFileNames() returns an empty list; but I can see I have multiple files in the folder.  
When I rename the folder to remove the Japanese characters then loading works fine.

Is there something that I am missing here ? I am using (and kinda stuck with) ITK 4.13

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### Author: ![nathanm](https://discourse.itk.org/letter_avatar_proxy/v4/letter/n/e274bd/32.png) [@nathanm](https://discourse.itk.org/u/nathanm)
#### Post date: [March 10, 2021, 4:35pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/2 "2021-03-10T16:35:06Z")

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I have exactly the problem described here: I’m trying to open a DICOM dataset (in my case with Chinese characters in the directory) and GDCMSeriesFileNames won’t find the files in the folder.

When removing Chinese characters it works properly, but modifying the directory to remove non-ASCII characters is not an option for me. Any idea on this issue? I’m with latest ITK 5.2.

Thanks,  
Nathan

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### Author: ![matt.mccormick](https://discourse.itk.org/user_avatar/discourse.itk.org/matt.mccormick/32/7_2.png) [@matt.mccormick](https://discourse.itk.org/u/matt.mccormick)
#### Post date: [March 10, 2021, 4:50pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/3 "2021-03-10T16:50:20Z")

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Hi @nathanm ,

Perhaps setting the locale similar to this issue:

> <https://github.com/InsightSoftwareConsortium/ITK/pull/2297>

in `itk::GDCMSeriesFileNames` addresses the issue?

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### Author: ![nathanm](https://discourse.itk.org/letter_avatar_proxy/v4/letter/n/e274bd/32.png) [@nathanm](https://discourse.itk.org/u/nathanm)
#### Post date: [March 10, 2021, 5:02pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/4 "2021-03-10T17:02:47Z")

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Hi @matt.mccormick , thank you for prompt reply.

I checked the link you provided and it seems pretty much related. How should I try this? Is it a branch of ITK to be merged with the bug fix? Or how do I set the locale?

Nathan

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### Author: ![matt.mccormick](https://discourse.itk.org/user_avatar/discourse.itk.org/matt.mccormick/32/7_2.png) [@matt.mccormick](https://discourse.itk.org/u/matt.mccormick)
#### Post date: [March 10, 2021, 5:25pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/5 "2021-03-10T17:25:29Z")

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Hi Nathan,

To try a fix, [set up a repository for contributing to ITK](https://github.com/InsightSoftwareConsortium/ITK/blob/master/CONTRIBUTING.md), a local build (more information can be found in [The ITK Software Guide](https://itk.org/ItkSoftwareGuide.pdf), then, like the patch did in _itkGDCMImageIO.cxx_, add ` std::locale currentLocale = std::locale::global(std::locale::classic());` and `std::locale::global(currentLocale);` around relevant blocks in _itkGDCMSeriesFileNames.cxx_.

Thanks,  
Matt

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### Author: ![lassoan](https://discourse.itk.org/user_avatar/discourse.itk.org/lassoan/32/27_2.png) [@lassoan](https://discourse.itk.org/u/lassoan)
#### Post date: [March 10, 2021, 8:03pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/6 "2021-03-10T20:03:42Z")

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In 3D Slicer, we switched to UTF-8 application code page and it solved all problems related to non-ASCII characters (except passing non-ASCII text via command-line arguments on Windows). On Linux and macOS UTF-8 code page should be the default, while on Windows you can [enable this in the application manifest](https://github.com/commontk/CTK/blob/master/CMake/ctkFunctionAddExecutableUtf8.cmake).

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<div class="post-metadata">

### Author: ![nathanm](https://discourse.itk.org/letter_avatar_proxy/v4/letter/n/e274bd/32.png) [@nathanm](https://discourse.itk.org/u/nathanm)
#### Post date: [March 11, 2021, 1:59pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/7 "2021-03-11T13:59:03Z")

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Hi @matt.mccormick,

I tried a similar fix to the one you linked, with no success so far…

Hi @lassoan,

In order to enable this application manifest in Windows (`WindowsApplicationUseUtf8.manifest`), what’s the procedure to follow exactly? I’m using Visual Studio C++ to create a dynamic library (.dll).

Thank you,  
Nathan

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<div class="post-metadata">

### Author: ![lassoan](https://discourse.itk.org/user_avatar/discourse.itk.org/lassoan/32/27_2.png) [@lassoan](https://discourse.itk.org/u/lassoan)
#### Post date: [November 14, 2021, 11:48pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/8 "2021-11-14T23:48:22Z")

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> [@nathanm](#):
>
> In order to enable this application manifest in Windows (`WindowsApplicationUseUtf8.manifest`), what’s the procedure to follow exactly? I’m using Visual Studio C++ to create a dynamic library (.dll).

It cannot be set in a DLL, it must be set in the application. See how it is done in CTK at the link that I provided above.

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<div class="post-metadata">

### Author: ![codeling](https://discourse.itk.org/user_avatar/discourse.itk.org/codeling/32/2214_2.png) [@codeling](https://discourse.itk.org/u/codeling)
#### Post date: [June 4, 2024, 12:29pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/9 "2024-06-04T12:29:34Z")

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Sorry to revive such an old topic, but I needed to remark here that your post, @lassoan, on adding the manifest was most helpful in finally getting proper utf-8 support on Windows! Thanks a lot 🙏 🙏 🙏!

The only minor nuisance now remaining (in Debug mode) are a number of debug assertion failures, sometimes (interestingly not always) happening when unicode characters are present in a file name, from `CanReadFile` method in the `NiftiImageIO`:

```auto
Debug Assertion Failed!
...
File: minkernel\crts\ucrt\src\appcrt\convert\isctype.cpp
Line: 36

Expression: c >= -1 && c <= 255

```

Stack trace:

```auto
 	ucrtbased.dll...
 	...
	ITKIONIFTI-5.4.dll!make_lowercase(char * str) Line 3327	C
	ITKIONIFTI-5.4.dll!nifti_find_file_extension(const char * name) Line 2637	C
	ITKIONIFTI-5.4.dll!nifti_validfilename(const char * fname) Line 2567	C
	ITKIONIFTI-5.4.dll!is_nifti_file(const char * hname) Line 3471	C
	ITKIONIFTI-5.4.dll!itk::NiftiImageIO::CanReadFile(const char * FileNameToRead) Line 887	C++
	ITKIOImageBase-5.4.dll!itk::ImageIOFactory::CreateImageIO(const char * path, itk::CommonEnums::IOFileMode mode) Line 55	C++

```

But we can easily live with those 🙂

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<div class="post-metadata">

### Author: ![lassoan](https://discourse.itk.org/user_avatar/discourse.itk.org/lassoan/32/27_2.png) [@lassoan](https://discourse.itk.org/u/lassoan)
#### Post date: [June 5, 2024, 5:51pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/10 "2024-06-05T17:51:03Z")

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The error seems to be due to a bug in niftilib - in how it [prepares input data for `isupper` or `tolower`](https://github.com/InsightSoftwareConsortium/ITK/blob/21851448adfe9b81790f0f370314b8c1a21fbdba/Modules/ThirdParty/NIFTI/src/nifti/niftilib/nifti1_io.c#L3338). Since you can already reproduce the problem on your computer, the best would be if you could fix it and submit a pull request to ITK.

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### Author: ![seanm](https://discourse.itk.org/letter_avatar_proxy/v4/letter/s/a88e4f/32.png) [@seanm](https://discourse.itk.org/u/seanm)
#### Post date: [June 14, 2024, 4:30pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/11 "2024-06-14T16:30:07Z")

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> The error seems to be due to a bug in niftilib - in how it [prepares input data for `isupper` or `tolower`]

If it’s nifti\_clib bug, best would be to fix it upstream:

> **[GitHub - NIFTI-Imaging/nifti\_clib: C libraries for NIFTI support](https://github.com/NIFTI-Imaging/nifti_clib)**
>
> C libraries for NIFTI support. Contribute to NIFTI-Imaging/nifti\_clib development by creating an account on GitHub.

or at least create an Issue there.

Sean

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<div class="post-metadata">

### Author: ![lassoan](https://discourse.itk.org/user_avatar/discourse.itk.org/lassoan/32/27_2.png) [@lassoan](https://discourse.itk.org/u/lassoan)
#### Post date: [June 16, 2024, 7:21pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/12 "2024-06-16T19:21:50Z")

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> [@seanm](#):
>
> If it’s nifti\_clib bug, best would be to fix it upstream:

Right, I just did not want to scare @codeling with this extra task, but definitely the ultimate solution is to fix this bug is to fix it in [GitHub - NIFTI-Imaging/nifti\_clib: C libraries for NIFTI support](https://github.com/NIFTI-Imaging/nifti_clib).

@codeling it may be worth a try submitting a bug report to [nifti\_clib](https://github.com/NIFTI-Imaging/nifti_clib). Maybe developers fix it for you quickly and then you can ask ITK developers to update ITK’s implementation.

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<div class="post-metadata">

### Author: ![codeling](https://discourse.itk.org/user_avatar/discourse.itk.org/codeling/32/2214_2.png) [@codeling](https://discourse.itk.org/u/codeling)
#### Post date: [June 17, 2024, 8:19pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/13 "2024-06-17T20:19:12Z")

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I am sorry but I currently do neither have the time to look into this further nor do a proper bug report, and as I said, for me it’s far away from being a critical issue. Just wanted to share my findings!

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### Author: ![seanm](https://discourse.itk.org/letter_avatar_proxy/v4/letter/s/a88e4f/32.png) [@seanm](https://discourse.itk.org/u/seanm)
#### Post date: [June 17, 2024, 9:30pm UTC](https://discourse.itk.org/t/gdcmseriesfilenames-fails-to-read-folder-with-non-ascii-characters/2365/14 "2024-06-17T21:30:32Z")

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I took 5 minutes to write up a ticket: [Unicode filename problems on Windows because of isupper() and tolower() · Issue #189 · NIFTI-Imaging/nifti\_clib · GitHub](https://github.com/NIFTI-Imaging/nifti_clib/issues/189)