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arXiv 1502.00836cs.CV
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基于任务驱动字典学习的高光谱图像分类

Task-Driven Dictionary Learning for Hyperspectral Image Classification with Structured Sparsity Constraints

The Johns Hopkins University(约翰斯·霍普金斯大学);U.S. Army Research Laboratory(美国陆军研究实验室)

Xiaoxia Sun, Nasser M. Nasrabadi, Trac D. Tran

摘要:

稀疏表示将信号建模为少量字典原子的线性组合。作为一种生成模型,它要求字典是高度冗余的,以确保信号的稳定的高稀疏水平和低重构误差。然而,在实践中,这一要求通常是削弱了缺乏标记的训练样本。幸运的是,以前的研究表明,冗余字典的要求可以不那么严格,如果采用同时稀疏近似,这可以通过对相邻像素的稀疏代码执行各种结构化稀疏约束来进行。此外,大量的工作表明,应用各种字典学习方法的稀疏表示模型也可以提高分类性能。在本文中,我们强调任务驱动的字典学习算法,这是一个一般的框架监督字典学习方法。我们建议在任务驱动的字典学习方法中加入结构化稀疏先验,以提高高光谱分类的性能。我们的方法能够受益于同时稀疏表示和监督字典学习的优点。我们执行两个不同的结构稀疏先验,联合和拉普拉斯稀疏,任务驱动的字典学习方法,并提供相应的优化算法的细节。大量流行的高光谱图像上的实验表明,我们的方法的分类性能优于稀疏表示分类器与结构化先验或任务驱动的字典学习方法。

英文摘要:

Sparse representation models a signal as a linear combination of a small number of dictionary atoms. As a generative model, it requires the dictionary to be highly redundant in order to ensure both a stable high sparsity level and a low reconstruction error for the signal. However, in practice, this requirement is usually impaired by the lack of labelled training samples. Fortunately, previous research has shown that the requirement for a redundant dictionary can be less rigorous if simultaneous sparse approximation is employed, which can be carried out by enforcing various structured sparsity constraints on the sparse codes of the neighboring pixels. In addition, numerous works have shown that applying a variety of dictionary learning methods for the sparse representation model can also improve the classification performance. In this paper, we highlight the task-driven dictionary learning algorithm, which is a general framework for the supervised dictionary learning method. We propose to enforce structured sparsity priors on the task-driven dictionary learning method in order to improve the performance of the hyperspectral classification. Our approach is able to benefit from both the advantages of the simultaneous sparse representation and those of the supervised dictionary learning. We enforce two different structured sparsity priors, the joint and Laplacian sparsity, on the task-driven dictionary learning method and provide the details of the corresponding optimization algorithms. Experiments on numerous popular hyperspectral images demonstrate that the classification performance of our approach is superior to sparse representation classifier with structured priors or the task-driven dictionary learning method.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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