CT Image Denoising using Discrete Wavelet Transform
Research Article  ·  Published: 22 September 2025
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Biomedical Informatics and Smart Healthcare
Volume 1, Issue 2, 2025: 44-51
Research Article Open Access

CT Image Denoising using Discrete Wavelet Transform

1 School of Computer Science and Artificial Intelligence, SR University, Warangal, India
* Corresponding Author: Swapna Katta, [email protected]
Volume 1, Issue 2

Article Information

Abstract

Low Dose Computed Tomography (LDCT) scan is modern medical imaging diagnostic technique that provides a detailed projection of internal human body tissue level structures. Even though the LDCT image quality is compromised by Gaussian-noise, which can be generated during image acquisition, this compromises the accurate diagnostic precision. The effective denoising is required to improve image quality in LDCT images. This study demonstrates that the Discrete Wavelet Transform(DWT) method shows better results, both quantitatively and visually, under varying noise intensities ($\sigma=10,20,30,$ and $40$). The DWT method decomposes the image to multiresolution subbands (approximation, and detail) to provide localized analysis of structural patterns. The thresholding method is applied to the detail (noisy) coefficients and then reconstructs the refined image from these denoised coefficients. The DWT method achieved superior noise suppression while preserving edge information. The quantitative analysis among various methods, including PCA, MSVD, DCT, and DWT, consistently shows superior results, achieving a higher PSNR of $33.85$ dB, SNR of $28.50$ dB, and SSIM of $0.7194$ at a noise level $\sigma =10$. Among all denoising methods, the DWT is a powerful and consistent method in image processing to enhance image quality in LDCT images.

Graphical Abstract

CT Image Denoising using Discrete Wavelet Transform

Keywords

CT image denoising Gaussian noise DWT Transform domain

Data Availability Statement

Data will be made available on request.

Funding

This work was supported without any funding.

Conflicts of Interest

The authors declare no conflicts of interest.

Ethical Approval and Consent to Participate

Not applicable. This study is based on a publicly available dataset (SARS-CoV-2 CT-scan dataset) and does not involve any new collection of human or animal data, patient interactions, or ethical interventions requiring approval from an institutional review board.

References

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Cited By (1)

  1. Sai Bhargav Kasetty, Rajakumar Krishnan. A unified comparative framework for multiscale geometric transforms in SAR and multispectral satellite image analysis. Frontiers in Remote Sensing, 2026 , 7 .
    [CrossRef]
* Citation data provided by Crossref Cited-by.

Cite This Article

APA Style
Katta, S., & Garg, D. (2025). CT Image Denoising using Discrete Wavelet Transform. Biomedical Informatics and Smart Healthcare, 1(2), 44–51. https://doi.org/10.62762/BISH.2025.874472
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TY  - JOUR
AU  - Katta, Swapna
AU  - Garg, Deepak
PY  - 2025
DA  - 2025/09/22
TI  - CT Image Denoising using Discrete Wavelet Transform
JO  - Biomedical Informatics and Smart Healthcare
T2  - Biomedical Informatics and Smart Healthcare
JF  - Biomedical Informatics and Smart Healthcare
VL  - 1
IS  - 2
SP  - 44
EP  - 51
DO  - 10.62762/BISH.2025.874472
UR  - https://www.icck.org/article/abs/BISH.2025.874472
KW  - CT image
KW  - denoising Gaussian noise
KW  - DWT
KW  - Transform domain
AB  - Low Dose Computed Tomography (LDCT) scan is modern medical imaging diagnostic technique that provides a detailed projection of internal human body tissue level structures. Even though the LDCT image quality is compromised by Gaussian-noise, which can be generated during image acquisition, this compromises the accurate diagnostic precision. The effective denoising is required to improve image quality in LDCT images. This study demonstrates that the Discrete Wavelet Transform(DWT) method shows better results, both quantitatively and visually, under varying noise intensities ($\sigma=10,20,30,$ and $40$). The DWT method decomposes the image to multiresolution subbands (approximation, and detail) to provide localized analysis of structural patterns. The thresholding method is applied to the detail (noisy) coefficients and then reconstructs the refined image from these denoised coefficients. The DWT method achieved superior noise suppression while preserving edge information. The quantitative analysis among various methods, including PCA, MSVD, DCT, and DWT, consistently shows superior results, achieving a higher PSNR of $33.85$ dB, SNR of $28.50$ dB, and SSIM of $0.7194$ at a noise level $\sigma =10$. Among all denoising methods, the DWT is a powerful and consistent method in image processing to enhance image quality in LDCT images.
SN  - 3068-5524
PB  - Institute of Central Computation and Knowledge
LA  - English
ER  - 
BibTeX Format
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@article{Katta2025CT,
  author = {Swapna Katta and Deepak Garg},
  title = {CT Image Denoising using Discrete Wavelet Transform},
  journal = {Biomedical Informatics and Smart Healthcare},
  year = {2025},
  volume = {1},
  number = {2},
  pages = {44-51},
  doi = {10.62762/BISH.2025.874472},
  url = {https://www.icck.org/article/abs/BISH.2025.874472},
  abstract = {Low Dose Computed Tomography (LDCT) scan is modern medical imaging diagnostic technique that provides a detailed projection of internal human body tissue level structures. Even though the LDCT image quality is compromised by Gaussian-noise, which can be generated during image acquisition, this compromises the accurate diagnostic precision. The effective denoising is required to improve image quality in LDCT images. This study demonstrates that the Discrete Wavelet Transform(DWT) method shows better results, both quantitatively and visually, under varying noise intensities (\$\sigma=10,20,30,\$ and \$40\$). The DWT method decomposes the image to multiresolution subbands (approximation, and detail) to provide localized analysis of structural patterns. The thresholding method is applied to the detail (noisy) coefficients and then reconstructs the refined image from these denoised coefficients. The DWT method achieved superior noise suppression while preserving edge information. The quantitative analysis among various methods, including PCA, MSVD, DCT, and DWT, consistently shows superior results, achieving a higher PSNR of \$33.85\$ dB, SNR of \$28.50\$ dB, and SSIM of \$0.7194\$ at a noise level \$\sigma =10\$. Among all denoising methods, the DWT is a powerful and consistent method in image processing to enhance image quality in LDCT images.},
  keywords = {CT image, denoising Gaussian noise, DWT, Transform domain},
  issn = {3068-5524},
  publisher = {Institute of Central Computation and Knowledge}
}

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CC BY Copyright © 2025 by the Author(s). Published by Institute of Central Computation and Knowledge. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.
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