Although image denoising is widely studied, the
effect of noise in image endures in image processing. Most
of the existing research works have used the basic noise
reduction through image blurring but without much
impact. As researchers continue to focus on the subject, it
is important to appreciate the need for effective denoising
methods for quality images. While some methods have
managed to denoise some types of noise, in the process they
affect the image quality. This research intended to establish
an approach for denoising images while maintaining the
image quality. To create this approach, several denoising
approaches and algorithms have been studied to determine
their shortcomings and a combination of two, i.e. Shearlet
Transform and PCA (Principle Component Analysis
Algorithm was deemed viable in adding value to the
existing denoising methods. The combination method
increases the superiority of the observed image,
subjectively and objectively.
Linnet N. Mugambi : is a career science teacher specializing in
mathematics and physics with an experience spanning over 10
years. Linnet is an ongoing student of a Master of Science
degree in computer systems at Jomo Kenyatta University of
Agriculture and Technology (JKUAT). She holds a bachelor of
education in science degree from Kenyatta University (2007)
and a diploma in science education from Kenya science
Teachers’ college (1998).
Waweru Mwangi : is an associate professor of information
systems engineering at Jomo Kenyatta University of Agriculture
and Technology (JKUAT) in the department of computing. He
holds a bachelor’s degree from Kenyatta University, a master’s
degree from Shanghai University (China) and a PhD degree
from Hokkaido University (Japan). His main research interest
includes Simulation and Modeling, Artificial Intelligence and
Dr. Michael W. Kimwele : is a Lecturer in the Department of
Computing, Jomo Kenyatta University of Agriculture and
technology (JKUAT). He holds a BSc. Mathematics and
Computer Science-First Class Honours from JKUAT (2002), a
Masters in Information Technology Management from University
of Sunderland-UK (2006) and a Doctorate in Information
Technology from JKUAT (2012). At present, he is the Associate
Chairman, Department of Information Technology, JKUATWestlands
Campus.Dr. Kimwele has authored a commendable
number of research papers in international/national
conference/journals and also supervises postgraduate students
in Computer Science/Information Technology. His research
interests include Information systems management, Information
Technology Security, Electronic Commerce, Mobile Computing,
Social implications of computer applications, Human Computer
Interaction, and Computer Ethics.
The combined method gives better results both byhuman
visual and by PSNR values Similarly, when the two
methods are used the properties of shearlet to enhance
and detect image edges and the property of PCA of
preserving image structures improves the final mage.
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