Gradient‐based edge preserving interpolation and its application to super‐resolution
Yutaro Iwamoto, Xian‐Hua Han, Tomoko Tateyama, Motonori Ohashi, So Sasatani, Yen‐Wei Chen · Electronics and Communications in Japan · 2012
Abstract Super‐resolution is a process for obtaining high‐quality, high‐resolution images from one or a set of low‐resolution images. The most practical methods for image super‐resolution are reconstruction‐based methods, which minimize the difference between observed low‐resolution images and the estimate for high‐resolution images. Therein, the interpolation step plays a key role in the estimated high‐resolution image quality. Usually, the conventional bilinear or bicubic methods are used in reconstruction‐based super‐resolution. However, these conventional interpolations generally lead to blurring in edge regions and need more time for convergence in the reconstruction‐based super‐resolution method. Therefore, this paper proposes a gradient‐based edge‐preserving interpolation method, which can reduce not only artifact noise but also blurring near the edge regions in the estimated high‐resolution image. Furthermore, our proposed interpolation method can also solve high‐complexity, time‐consuming problems in the recently developed new edge‐directed interpolation, which usually can achieve sharp edges in the high‐resolution reconstructed image. Experiments confirm that our proposed interpolation method for image super‐resolution is more effective than the conventional interpolation methods. © 2012 Wiley Periodicals, Inc. Electron Comm Jpn, 96(1): 43–50, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11413