VLSI implementation of color interpolation in color difference spaces

This paper presents a color interpolation processor for color-filter-array (CFA) based image sensor. We propose a modified color difference spaces interpolation method by using direction determination. Simulations show that the proposed method can achieve better quality-complexity tradeoff than other algorithms. For real-time VLSI implementation, a cost-effective architecture consisting of pipeline is designed based on our algorithm. The prototype of the color interpolation processor has been successfully verified on FPGA device. This design only uses about 25K gates and six line buffers on 0.18um process.