Octopus 8: A High Performance Tomographic Reconstruction Package for X-ray Tube and Synchrotron micro-CT

For 10 years the UGCT group has been applying micro-CT for the investigation of geomaterials with synchrotron and X-ray tube radiation. A new technique called element specific X-ray CT was developed and published. Dedicated software for tomographic reconstruction has been written during this period. The latest version, called Octopus 8, is a powerful and scanner independent package to process raw detector data into 2D slices through the object. Although the software engine is based on optimized C-code, the graphical interface makes it very user-friendly. A number of artifact and noise reduction algorithms are integrated to correct for ring artefacts, COR-misalignment, detector or stage tilt, pixel non-linearities ... Three different beam geometries are included: cone beam, parallel beam and fan beam. To increase the reconstruction speed we have developed a server/client option for Octopus which allows distributed computing. A nearly linear increase of performance can be obtained through cluster or grid processing. A new beam hardening correction approach makes it possible to reduce the streak and cupping artifacts due to the polychromatic nature of the X-ray tubes. The paper gives an overview of the most important features of Octopus, demonstrated on natural building materials.