Hole C0021B Whole Core X-ray CT Scanned Image, Expedition 338
The 3D X-ray CT images for whole-round core sections are the first measurement to be done on board. Whole-core photography and X-ray imaging provide information about surface features and internal structure. The resolution of CT scanning is under 0.35 mm and allows 5 mm depth for beam width. The computed tomography (CT) scan provides 3D evidence of fractures, vugs, fault structure, sedimentary structure and methane hydrates without disturbing the sample. A pure water standard piece and air is used for calibrate giving CT-values. It requires about 5 minutes to scan each 1.5 m section of core.
Each ZIP file corresponds to a section and the filename of a ZIP file consists of section identifier. A ZIP file contains DICOM files of axial images (See the figure) as well as a reformatted coronal image (See the figure). Each DICOM file has DICOM header with image data. Pixel data are compressed without any losses by JPEG2000 in the DICOM files (See Section 8.2.4. JPEG 2000 image compression in Digital Imaging and Communications in Medicine (DICOM) Part 5: Data Structures and Encoding distributed in DICOM Homepage).
Software utilities, not supported by JAMSTEC
GDCM is an open source DICOM library. It is meant to deal with DICOM files (as specified in part 10 of the DICOM standard).Command line tool gdcmconv can convert encapsulated DICOM to RAW by issuing a command like
gdcmconv --raw compressed.dcm uncompressed.dcm.
See also data in the database for the same hole to refer related information.