Edge feature extraction-based dual CNN for LDCT denoising

J Opt Soc Am A Opt Image Sci Vis. 2022 Oct 1;39(10):1929-1938. doi: 10.1364/JOSAA.462923.

Abstract

In low-dose computed tomography (LDCT) denoising tasks, it is often difficult to balance edge/detail preservation and noise/artifact reduction. To solve this problem, we propose a dual convolutional neural network (CNN) based on edge feature extraction (Ed-DuCNN) for LDCT. Ed-DuCNN consists of two branches. One branch is the edge feature extraction subnet (Edge_Net) that can fully extract the edge details in the image. The other branch is the feature fusion subnet (Fusion_Net) that introduces an attention mechanism to fuse edge features and noisy image features. Specifically, first, shallow edge-specific detail features are extracted by trainable Sobel convolutional blocks and then are integrated into Edge_Net together with the LDCT images to obtain deep edge detail features. Finally, the input image, shallow edge detail, and deep edge detail features are fused in Fusion_Net to generate the final denoised image. The experimental results show that the proposed Ed-DuCNN can achieve competitive performance in terms of quantitative metrics and visual perceptual quality compared with that of state-of-the-art methods.

MeSH terms

  • Image Processing, Computer-Assisted / methods
  • Neural Networks, Computer*
  • Signal-To-Noise Ratio
  • Tomography, X-Ray Computed* / methods