Fast voxel line update for time-space image reconstruction

Model based iterative reconstruction (MBIR) algorithms have been used to greatly improve image quality and temporal resolution in synchrotron based time-space Computed Tomography (CT). Among the various optimization methods that have been used for MBIR, iterative coordinate descent (ICD) has relatively lower computational requirements because it converges fast. In spite of that, long execution time remains a barrier for the widespread use of MBIR. In this paper, we present a new data structure, called VL-Buffer, for time-space reconstruction that significantly improves the cache locality while retaining good parallel performance. Experimental results show an average speedup of 40% using VL-Buffer.