A Portable and Unified CPU/GPU Parallel Implementation of Surface Normal Generation Algorithm from 3D Terrain Data

The Multi-mission Instrument Processing Lab (MIPL) is responsible for developing much of the ground support software for the Mars missions. The MIPL pipeline is used to generate several products from a one mega-pixel image within a 30 min time constraint. In future missions, this time constraint will be decreased to five minutes for 20 mega-pixels images, requiring a minimum 120 times speed-up from current operational hardware and software. Moreover, any changes to the current software must preserve the source code’s maintainability and portability for future missions. Therefore, the surface normal generation software has been implemented on a Graphical Processing Unit (GPU) through the use of the NVidia CUDA Toolkit and Hemi Library to allow for minimum code complexity. Several changes have been made to Hemi Library to allow for additional optimizations of the GPU code. In addition, several challenges to developing a parallelized GPU implementation of the surface normal generation algorithm are explored, while both tested and prospective solutions to these problems are described.