We previously proposed a method of generating free viewpoint images directly from multi-focus imaging sequences without any depth estimation. It is very effective for the method to be implemented to hardware such as FPGA. However, the number of BlockRAMs on our FPGA limits the image size to 64×64 pixels. In this paper, we extend our FPGA-based free viewpoint image reconstruction systems by using an on-board DDR SDRAM and processing the divided blocks of 64×64 pixels repeatedly. The system realizes our proposed method even for larger image size without great drawbacks. Some experimental results by using synthetic images are shown.