Comparative Evaluation between Fixed and Floating Point Hardware Implementation of Image Conversion on High-level Synthesis

High-level synthesis (HLS) automatically converts the software program in a high-level language to the hardware behavior in a hardware description language. Generally, the image processing programs have been written in floating-point format. Thus, inputting such conventional image processing programs, the HLS tool generates the hardware modules with many floating-point calculators. The floating-point calculator generally requires a large amount of hardware resources. Thus, this paper develops the fixed-point image processing programs that will be converted to the hardware module including light-weight fixed-point calculators, concentrating on the image conversions such as scaling, rotation and shear. In the experiment, we confirm the effect of the fixed-point programming for the HLS compared with the floating point one.