A Design of Optimized Colour Image Interpolation Algorithm Based on Edge Gradient

Most of the popular digital cameras are equipped with image sensors of Complementary Metal Oxide Semiconductor(CMOS), in which the Bayer filter is used to store the information of the image. The original image obtained from Bayer filter is then restored to colour by interpolation algorithms. However, there has been low quality with recovered image. In order to solve this problem, an optimization based on the edge gradient interpolation algorithm is proposed in this paper. Firstly, more accurate edges for interpolation are obtained by re-optimizing the calculation of the horizontal and vertical gradients. Then, the missing channels are recovered by the method of intra-neighbourhood averaging, mainly 3x3 neighbourhood. Several sets of comparison experiments based on MATLAB were conducted and the colour peak signal-to-noise ratio was introduced to evaluate the image quality. It has proved that the optimized algorithm proposed in this paper recovers colour images with higher quality compared to the traditional edge gradient interpolation algorithm