High-level design using Intel FPGA OpenCL: A hyperspectral imaging spatial-spectral classifier

Current computational demands require increasing designer's efficiency and system performance per watt. A broadly accepted solution for efficient accelerators implementation is reconfigurable computing. However, typical HDL methodologies require very specific skills and a considerable amount of designer's time. Despite the new approaches to high-level synthesis like OpenCL, given the large heterogeneity in today's devices (manycore, CPUs, GPUs, FPGAs), there is no one-fits-all solution, so to maximize performance, platform-driven optimization is needed. This paper reviews some latest works using Intel FPGA SDK for OpenCL and the strategies for optimization, evaluating the framework for the design of a hyperspectral image spatial-spectral classifier accelerator. Results are reported for a Cyclone V SoC using Intel FPGA OpenCL Offline Compiler 16.0 out-of-the-box. From a common baseline C implementation running on the embedded ARM® Cortex®-A9, OpenCL-based synthesis is evaluated applying different generic and vendor specific optimizations. Results show how reasonable speedups are obtained in a device with scarce computing and embedded memory resources. It seems a great step has been given to effectively raise the abstraction level, but still, a considerable amount of HW design skills is needed.