Speckle Noise Removal in OCT Images via Wavelet Transform and DnCNN

(1) Background: Due to its imaging principle, OCT generates images laden with significant speckle noise. The quality of OCT images is a crucial factor influencing diagnostic effectiveness, highlighting the importance of OCT image denoising. (2) Methods: The OCT image undergoes a Discrete Wavelet Tra...

Full description

Saved in:
Bibliographic Details
Main Authors: Fangfang Li, Qizhou Wu, Bei Jia, Zhicheng Yang
Format: Article
Language:English
Published: MDPI AG 2025-06-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/15/12/6557
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849418288518397952
author Fangfang Li
Qizhou Wu
Bei Jia
Zhicheng Yang
author_facet Fangfang Li
Qizhou Wu
Bei Jia
Zhicheng Yang
author_sort Fangfang Li
collection DOAJ
description (1) Background: Due to its imaging principle, OCT generates images laden with significant speckle noise. The quality of OCT images is a crucial factor influencing diagnostic effectiveness, highlighting the importance of OCT image denoising. (2) Methods: The OCT image undergoes a Discrete Wavelet Transform (DWT) to decompose it into multiple scales, isolating high-frequency wavelet coefficients that encapsulate fine texture details. These high-frequency coefficients are further processed using a Shift-Invariant Wavelet Transform (SWT) to generate an additional set of coefficients, ensuring an enhanced feature preservation and reduced artifacts. Both the original DWT high-frequency coefficients and their SWT-transformed counterparts are independently denoised using a Deep Neural Convolutional Network (DnCNN). This dual-pathway approach leverages the complementary strengths of both transform domains to suppress noise effectively. The denoised outputs from the two pathways are fused using a correlation-based strategy. This step ensures the optimal integration of texture features by weighting the contributions of each pathway according to their correlation with the original image, preserving critical diagnostic information. Finally, the Inverse Wavelet Transform is applied to the fused coefficients to reconstruct the denoised OCT image in the spatial domain. This reconstruction step maintains structural integrity and enhances diagnostic clarity by preserving essential spatial features. (3) Results: The MSE, PSNR, and SSIM indices of the proposed algorithm in this paper were 4.9052, 44.8603, and 0.9514, respectively, achieving commendable results compared to other algorithms. The Sobel, Prewitt, and Canny operators were utilized for edge detection on images, which validated the enhancement effect of the proposed algorithm on image edges. (4) Conclusions: The proposed algorithm in this paper exhibits an exceptional performance in noise suppression and detail preservation, demonstrating its potential application in OCT image denoising. Future research can further explore the adaptability and optimization directions of this algorithm in complex noise environments, aiming to provide more theoretical support and practical evidence for enhancing OCT image quality.
format Article
id doaj-art-a2cdba41fe2d4a08b2aa3b722b6f8c3e
institution Kabale University
issn 2076-3417
language English
publishDate 2025-06-01
publisher MDPI AG
record_format Article
series Applied Sciences
spelling doaj-art-a2cdba41fe2d4a08b2aa3b722b6f8c3e2025-08-20T03:32:28ZengMDPI AGApplied Sciences2076-34172025-06-011512655710.3390/app15126557Speckle Noise Removal in OCT Images via Wavelet Transform and DnCNNFangfang Li0Qizhou Wu1Bei Jia2Zhicheng Yang3School of Information and Communication Engineering, North University of China, Taiyuan 030051, ChinaSchool of Information and Communication Engineering, North University of China, Taiyuan 030051, ChinaSchool of Information and Communication Engineering, North University of China, Taiyuan 030051, ChinaSchool of Information and Communication Engineering, North University of China, Taiyuan 030051, China(1) Background: Due to its imaging principle, OCT generates images laden with significant speckle noise. The quality of OCT images is a crucial factor influencing diagnostic effectiveness, highlighting the importance of OCT image denoising. (2) Methods: The OCT image undergoes a Discrete Wavelet Transform (DWT) to decompose it into multiple scales, isolating high-frequency wavelet coefficients that encapsulate fine texture details. These high-frequency coefficients are further processed using a Shift-Invariant Wavelet Transform (SWT) to generate an additional set of coefficients, ensuring an enhanced feature preservation and reduced artifacts. Both the original DWT high-frequency coefficients and their SWT-transformed counterparts are independently denoised using a Deep Neural Convolutional Network (DnCNN). This dual-pathway approach leverages the complementary strengths of both transform domains to suppress noise effectively. The denoised outputs from the two pathways are fused using a correlation-based strategy. This step ensures the optimal integration of texture features by weighting the contributions of each pathway according to their correlation with the original image, preserving critical diagnostic information. Finally, the Inverse Wavelet Transform is applied to the fused coefficients to reconstruct the denoised OCT image in the spatial domain. This reconstruction step maintains structural integrity and enhances diagnostic clarity by preserving essential spatial features. (3) Results: The MSE, PSNR, and SSIM indices of the proposed algorithm in this paper were 4.9052, 44.8603, and 0.9514, respectively, achieving commendable results compared to other algorithms. The Sobel, Prewitt, and Canny operators were utilized for edge detection on images, which validated the enhancement effect of the proposed algorithm on image edges. (4) Conclusions: The proposed algorithm in this paper exhibits an exceptional performance in noise suppression and detail preservation, demonstrating its potential application in OCT image denoising. Future research can further explore the adaptability and optimization directions of this algorithm in complex noise environments, aiming to provide more theoretical support and practical evidence for enhancing OCT image quality.https://www.mdpi.com/2076-3417/15/12/6557OCT imageimage denoisingdiscrete wavelet transformstationary wavelet transformdenoising convolutional neural network
spellingShingle Fangfang Li
Qizhou Wu
Bei Jia
Zhicheng Yang
Speckle Noise Removal in OCT Images via Wavelet Transform and DnCNN
Applied Sciences
OCT image
image denoising
discrete wavelet transform
stationary wavelet transform
denoising convolutional neural network
title Speckle Noise Removal in OCT Images via Wavelet Transform and DnCNN
title_full Speckle Noise Removal in OCT Images via Wavelet Transform and DnCNN
title_fullStr Speckle Noise Removal in OCT Images via Wavelet Transform and DnCNN
title_full_unstemmed Speckle Noise Removal in OCT Images via Wavelet Transform and DnCNN
title_short Speckle Noise Removal in OCT Images via Wavelet Transform and DnCNN
title_sort speckle noise removal in oct images via wavelet transform and dncnn
topic OCT image
image denoising
discrete wavelet transform
stationary wavelet transform
denoising convolutional neural network
url https://www.mdpi.com/2076-3417/15/12/6557
work_keys_str_mv AT fangfangli specklenoiseremovalinoctimagesviawavelettransformanddncnn
AT qizhouwu specklenoiseremovalinoctimagesviawavelettransformanddncnn
AT beijia specklenoiseremovalinoctimagesviawavelettransformanddncnn
AT zhichengyang specklenoiseremovalinoctimagesviawavelettransformanddncnn