Linear Interpolation Algorithms and their Architectures for Image Scaling – A Survey

Image interpolation is the process of increasing the number of pixels in an image such that the image is enlarged. Interpolation is commonly called as image upscaling, image zooming or image magnification. Linear Interpolation (LI) is fast, cost effective and has low power consumption. It also provides a better image quality. It requires only two pixels to calculate the interpolated pixel value. Applications of LI include computer graphics, medical imaging, remote sensing and multimedia applications (e.g. video teleconferencing). In this survey, various types of LI algorithms and their hardware architectures are analyzed and compared. These algorithms are implemented for different Very Large Scale Integrated Circuit (VLSI) based implementations such as Field Programmable Gate Array (FPGA) and Complementary Metal Oxide Semiconductor (CMOS) technologies. These interpolation algorithms are compared with respect to various parameters like Peak Signal to Noise Ratio (PSNR) and gate count. Based on the evaluation, it is observed that Adder Based Stepwise linear Interpolation (ABSI) method provides better image quality with reduced chip area