[Insight-users] DicomSeriesReadImageWrite2

[Luis Ibanez]

Hi 예동해


David Clunie kindly pointed out to me the following:

> JPEG lossy (DCT) compression is limited by the JPEG standard
> to 12 bits, because of the word length precision limitations of
> the discrete cosine transformation implementation specification,
> but lossless compression should be supported for 16 bits.
> 


Which lead to think that the warning produced by the JPEG
libraries is incorrect, or that there is something wrong
with the DICOM header of your data.


Could you please try by forcing the GDCMImageIO class to
use JPEG2000 ?

You can do this with the following call:


gdcmImageIO->SetCompressionType( itk::GDCMImageIO::JPEG2000 );



Please try this and let us know if you still receive any
warnings.


  Thanks


    Luis



==============
예동해 wrote:
> First of all, thank you for your concern.
> 
>  
> 
> However, I need your more help.
> 
>  
> 
> I have no idea about how to change the compression mode.
> 
>  
> 
> How can I change lossless compression mode to lossy compression mode?
> 
> 
> Please help me out.
> 
>  
> 
> I'm looking forward to your reply.
> 
>  
> 
> Thank you.
> 
>  
> 
> --- Original Message ---
> *From : * "Luis Ibanez"<luis.ibanez at kitware.com>
> *To : * "예동해"<eastsun3 at snu.ac.kr>
> *Date : * 2006/12/31 일요일 오후 11:38:46
> *Subject : * Re: [Insight-users] DicomSeriesReadImageWrite2
> 
> 
> Hi 예동해
> 
> 
> Are you reading DICOM compressed files ?
> 
> 
> 
> The message:
> 
> "Must downscale data from 16 bits to 12"
> 
> is produced by the JPEG libraries.
> 
> 
> The message is generated from
> 
> Insight/Utilities/itkjpeg/jdinput.c line 54
> 
> when you attempt to use LOSSLESS compression.
> 
> 
> Your options seems to be:
> 
> 
> 
> A) Use Lossy compression
> 
> or
> 
> B) Set the number of bits to 12
> 
> 
> 
> 
> Regards,
> 
> 
> 
> Luis
> 
> 
> 
> ------------
> 예동해 wrote:
>  > Dear all,
>  >
>  > I am trying to convert .dic to .img.
>  >
>  > I used DicomSeriesReadImageWrite2.exe on the example.
>  >
>  >
>  >
>  > It works good, but some warning message comes out.
>  >
>  > The message is "Must downscale data from 16 bits to 12"
>  >
>  >
>  >
>  > How can I get .img without this warning message?
>  >
>  >
>  >
>  > Thank you for your help.
>  >
>  >
>  >
>  >
>  >
>  >
>  >
>  > ------------------------------------------------------------------------
>  >
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