返回
Convolutional Analysis Operator Learning: Acceleration and Convergence
DOI:10.1109/TIP.2019.2937734.png)
摘要
En 中文
Convolutional operator learning is gaining attention in many signal processing and computer vision applications. Learning kernels has mostly relied on so-called patch-domain approaches that extract and store many overlapping patches across training signals. Due to memory demands, patch-domain methods have limitations when learning kernels from large datasets - particularly with multi-layered structures, e.g., convolutional neural networks - or when applying the learned kernels to high-dimensional signal recovery problems. The so-called convolution approach does not store many overlapping patches, and thus overcomes the memory problems particularly with careful algorithmic designs; it has been studied within the synthesis signal model, e.g., convolutional dictionary learning. This paper proposes a new convolutional analysis operator learning (CAOL) framework that learns an analysis sparsifying regularizer with the convolution perspective, and develops a new convergent Block Proximal Extrapolated Gradient method using a Majorizer (BPEG-M) to solve the corresponding block multi-nonconvex problems. To learn diverse filters within the CAOL framework, this paper introduces an orthogonality constraint that enforces a tight-frame filter condition, and a regularizer that promotes diversity between filters. Numerical experiments show that, with sharp majorizers, BPEG-M significantly accelerates the CAOL convergence rate compared to the state-of-the-art block proximal gradient (BPG) method. Numerical experiments for sparse-view computational tomography show that a convolutional sparsifying regularizer learned via CAOL significantly improves reconstruction quality compared to a conventional edge-preserving regularizer. Using more and wider kernels in a learned regularizer better preserves edges in reconstructed images.
Keyword:
Convolution
Training
Kernel
Convolutional codes
Computed tomography
Convergence
Image reconstruction
Convolutional regularizer learning
convolutional dictionary learning
convolutional neural networks
unsupervised machine learning algorithms
nonconvex-nonsmooth optimization
block coordinate descent
inverse problems
X-ray computed tomography
AI总结
对已上传原文的论文进行重点信息的提取,主要内容包括:简要概述、研究摘要、背景介绍、关键亮点、图文解析、展望与总结。
期刊
IF:
13.7
论文数:
1.0W
被引数:
8.4W
机构
引用论文
Presenting Concerns of Veterans Entering Treatment for Posttraumatic Stress Disorder提出退伍军人进入创伤后应激障碍治疗的担忧
Small Silencing RNAs in Plants Are Mobile and Direct Epigenetic Modification in Recipient Cells
Science
IF0
Developing indicators of sustainable community: Lessons from sustainable Seattle制定可持续社区的指标: 西雅图可持续发展的经验教训
A micromachined efficient parametric array loudspeaker with a wide radiation frequency band具有宽辐射频带的微机械高效参量阵列扬声器
LEARN: Learned Experts' Assessment-Based Reconstruction Network for Sparse-Data CT学习: 基于专家评估的稀疏数据CT重建网络

