[Insight-users] use itk::ImageFileReader to read a dicom file without extension ???

[Iván Macía]

> -----Mensaje original-----
> De: Iván Macía [mailto:imacia at vicomtech.org]
> Enviado el: lunes, 02 de marzo de 2009 16:16
> Para: 'Mathieu Malaterre'; 'wassim_belhadj at topnet.tn'
> CC: 'insight-users at itk.org'
> Asunto: RE: [Insight-users] use itk::ImageFileReader to read a dicom
> file without extension ???
> 
> > -----Mensaje original-----
> > De: insight-users-bounces at itk.org [mailto:insight-users-
> > bounces at itk.org] En nombre de Mathieu Malaterre
> > Enviado el: lunes, 02 de marzo de 2009 14:12
> > Para: wassim_belhadj at topnet.tn
> > CC: insight-users at itk.org
> > Asunto: Re: [Insight-users] use itk::ImageFileReader to read a dicom
> > file without extension ???
> >
> > On Mon, Mar 2, 2009 at 12:12 PM,  <wassim_belhadj at topnet.tn> wrote:
> > > hi
> > > How to use itk::ImageFileReader to read a dicom file without
> > extension
> > >
> > >
> > >   typedef   unsigned char                      InternalPixelType;
> > >   typedef   unsigned char                      OutputPixelType;
> > >   const     unsigned int                       Dimension = 2;
> > >
> > >   typedef itk::Image< InternalPixelType, Dimension >
> > InternalImageType;
> > >   typedef itk::Image< OutputPixelType, Dimension > OutputImageType;
> > >
> > >    typedef  itk::ImageFileReader< InternalImageType > ReaderType;
> > >    typedef  itk::ImageFileWriter<  OutputImageType  > WriterType;
> > >
> > >    ReaderType::Pointer reader = ReaderType::New();
> > >    WriterType::Pointer writer = WriterType::New();
> > >
> > >    ReaderType::Pointer reader = ReaderType::New();
> > >    WriterType::Pointer writer = WriterType::New();
> > >
> > >
> > >    reader->SetFileName("IMG0045");
> > >
> > >    writer->SetFileName( "Res");
> > >
> > >   .....
> > >
> > > It does not work -It works when i use The File Extension  like
> > IMG0045.dcm
> > > and Res. dcm -
> >
> >
> > By default itk::GDCMImageIO will properly detects valid DICOM file
> > (ref: PS 3.10-2008 from standard) even when no extension is
> specifiied
> > (.dcm is not required by the standard). So your file is not a valid
> > DICOM file, it is missing at least the magic number 'DICM' (at Offset
> > 128) to properly be detected.
> > If this is correct, check with your vendor on how to obtain proper
> > (valid) DICOM files.
> >
> > 2cts
> > --
> > Mathieu
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> 
> Hi Mathieu,
> 
> Didn't read your answer, Outlook does not properly group conversations
> :(
> 
> A week ago we had exactly the same problem because no ImageIO was
> recognizing our extensionless DICOM. Either there is a bug or incorrect
> DICOM files are more common than expected.
> 
> We had to force usage of GDCM with SetImageIO(). The problem is I don't
> remember which file exactly, I will try to reproduce this.
> 
> Regards
> 
> Ivan
> 

Hi again,

Now I remember, the problem is when you try to WRITE an extensionless DICOM,
the ImageFileWriter throws an exception because it cannot decide which image
IO object to use for writing. Probably there is no problem in reading. You
can check this by doing separatedly reader->Update() and writer->Update().
The writer should throw an exception.

For the writer you need to specify .dcm as extension. 

Regards

Iván