DICOM open source (linux)

libmdc.

Medical Image (DICOM, ECAT, ...) conversion tool
This project stands for Medical Image Conversion. Released under the
(L)GPL, it comes with the full C-source code of the library, a
flexible command line utility and a neat graphical front-end using
the Gtk+ toolkit. The currently supported formats are: Acr/Nema 2.0,
Analyze (SPM), DICOM 3.0, InterFile 3.3 and PNG.

This is the central library needed by medcon, xmedcon and derived
programs

Homepage: http://xmedcon.sourceforge.net/

ImageMagick

пасиб, друзья, wikipedia - великая вешч :)

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http://www.creatis.insa-lyon.fr/Public/Gdcm/
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в VTK есть читалка