A novel interpolation scheme for rectangularly-subsampled images

Image interpolation is perhaps the only way to produce higher-resolution images from an original image with a lower resolution. A frequency-domain zero-masking technique was developed for interpolating hexagonally (or quincunx) subsampled images, with quite promising performances (particularly at low bit rates). In this paper, we focus on an interpolation scheme based on the same technique for another commonly used subsampling lattice-the rectangular grid. To this end, we propose a two-step spatial-domain interpolation in which each step consists of a hexagonal grid. Extensive simulations show that this scheme can provide excellent results in (very) low bit-rate interpolative JPEG coding