Contourlet Transform with Sparse Representation-Based Integrated Approach for Image Pansharpening

ABSTRACT

Pansharpening is an algorithmic approach to achieve high spatial resolution multispectral image. This paper proposes a new pansharpening method that is an integration of contourlet transform with sparse representation (CT-SR). CT is used to perform multiscale decomposition of input images to separate high-frequency and low-frequency subbands. High-frequency subbands are fused based on local energy calculation whereas SR using training dictionary is used to extract salient features to fuse low-frequency subbands. The synthesized multispectral image is obtained by combining fused low- and high-frequency subbands. It is observed that spatial resolution of synthesized multispectral image is improved, but at the same time, the original spectral resolution is also preserved. The detailed comparison between the resultant images of CT-SR and commonly used pansharpening techniques including wavelet transform with sparse representation are carried out at visual assessment level as well as through calculation of various performance indices. It is found that CT-SR performs is improved compared to other algorithms considered in this work.

KEYWORDS:

• Contourlet transform
• Sparse representation
• Spatial resolution
• Spectral resolution
• Fusion
• Pansharpening

DISCLOSURE STATEMENT

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Shailesh Panchal

Shailesh Panchal, born on 1978, received B. E. degree in Electronics and Communication from North Gujarat University, Patan in 1999 and M.Tech degree in Computer Science & Engineering from Nirma University, Ahmedabad in 2010. Since 2012, he has been working as an Associate Professor in Information Technology Department at Vishwakarma Government Engineering College, Chandkheda, Ahmedabad. His research interests are image processing and computer networking.E-mail: [email protected]

Rajesh A. Thakker

Rajesh A. Thakker, born on 1972, received B. E. degree in Electronics and Communication from Gujarat University, Ahmedabad in 1993, M.Tech and Ph.D. degree, in Electrical Engineering, from Indian Institute of Technology, Bombay in 2002 and 2009, respectively. Since 2013, he has been working as a Professor and Head of Electronics Communication Department at Vishwakarma Government Engineering College, Chandkheda, Ahmedabad. His research interests are VLSI, image processing, and applications of artificial intelligence in engineering.E-mail: [email protected]