Multifocus Image Fusion Based on Multiresolution Pyramid and Bilateral Filter

ABSTRACT

Multifocus image fusion is the process for enhancing the perception of a vision by combining substantial information captured by the camera from different focus points. It is very difficult to obtain a finer focus for all objects in the scene. The solution to the problem is to capture several multifocus images with different focal points, which are merged to obtain a single fused image with improved Depth of Field (DOF). The proposed method utilizes the unique significant texture features that are obtained from the Bilateral Filter (BLT). These unique features are used to compute weight map function that controls the transformation of details from multifocus source images to a single fused image. A pyramid-based multiresolution decomposition is proposed for analyzing spatial frequency components and then the fused image is reconstructed from modified spatially band-passed images by applying an inverse multiresolution transform. The fused image yields better results in terms of entropy, mean, standard deviation, average gradient, and PSNR values over existing state-of-the-art multifocus image fusion techniques. The proposed algorithm retains the actual shape of objects and also avoids the introduction of visible artifacts in the fused image.

KEYWORDS:

• Bilateral filter
• Detail layer
• Gaussian pyramid
• Laplacian pyramid
• Multifocus images

Additional information

Notes on contributors

Simrandeep Singh

Simrandeep Singh received his BTech and MTech degrees in electronics and communication engineering (ECE) from the Punjab Technical University in 2008 and 2015, respectively. He is pursuing PhD from Chandigarh University, Gharuan, Punjab, India. Currently, he is working as an assistant professor in the Department of ECE, Chandigarh University, Gharuan, India. He has 11 years of teaching experience. He has more than 15 research publications in various fields. His current research interests include diatom analysis based on multifocus image fusion, exposure fusion, edge-preserving filters, wireless sensor networks, and digital signal processing.

Nitin Mittal

Nitin Mittal received his BTech and MTech degrees in ECE from Kurukshetra University, Kurukshetra, India, in 2006 and 2009, respectively. He received his PhD in ECE from Chandigarh University, Mohali, India, in 2017. He is working as associate professor in the Department of ECE, Chandigarh University, Mohali, India. He has 10 years of teaching experience. He has more than 50 research publications in various fields. His research interests include wireless sensor networks, digital signal processing, multifocus image fusion, exposure fusion, and edge-preserving filters. Email: [email protected]

Harbinder Singh

Harbinder Singh has done PhD degree in ECE at the Jaypee University of Information Technology, Waknaghat, India, received the MTech degree in ECE from Punjab Technical University, Punjab, the BTech degree in ECE from Himachal Pradesh University. He is the author or co-author of 24 papers published in national, international conferences and journals. His current research interests include diatom analysis based on multifocus image fusion, exposure fusion, edge-preserving filters. Email: [email protected]