Image SR-based NLM and DCNN improved IBP with cubic B-spline

ABSTRACT

Image super-resolution (SR) techniques aim to estimate high-resolution (HR) image from low-resolution (LR) image. Existing SR method has slow convergence and recovery of high-frequency details are inaccurate. To overcome these issues, two algorithms have been proposed for image SR based on non-local means improved iterative back projection (NLM-IIBP), deep convolutional neural network improved iterative back projection (DCNN-IIBP) to produce high-resolution images with low noise, minimal blur by restoring high-frequency details. In NLM-IIBP denoised images have been interpolated using cubic B-spline interpolation and processed using IIBP based on guided bilateral method. NLM preserves the edges effectively, but does not consider high dimensional information and over smoothing during noise minimization. To further improve the resolution, NLM is replaced by DCNN. DCNN denoising method suppresses different noises at different noise levels. The proposed algorithms have been analysed and compared with existing approaches using various parameters to prove the effectiveness.

KEYWORDS:

• Non-local means
• edge preservation‌
• deep convolutional neural network
• improved iterative back projection
• cubic B-spline
• denoising
• guided bilateral filtering
• image restoration
• super-resolution

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes on contributors

S. Jothi Lakshmi received her Bachelor degree in Information Technology in the year 2007 and M.E. in Computer Science and Engineering in the year 2010 from Anna University, Chennai, Tamil Nadu, India. Currently she is a Full-Time Research Scholar, Department of ECE, Government College of Technology, Coimbatore, Tamil Nadu, India. Her research interests are in the areas of Image Processing.

P. Deepa received Bachelor Degree in Electronics and Communication Engineering in 2002 from Bharathiyar University, Coimbatore, Tamil Nadu, India. She received M.E. in VLSI Design in the year 2007 and Ph.D. degree in Information and Communication Engineering in 2013 from Anna University, Chennai, Tamil Nadu, India. She is working as an Assistant Professor, Department of Electronics and Communication Engineering, Government College of Technology, Coimbatore, Tamil Nadu, India. Her research area includes Low Power VLSI Design, Image Processing. Her research papers have been published in journals and presented paper in conferences.