81 research outputs found
Multispectral and Hyperspectral Image Fusion by MS/HS Fusion Net
Hyperspectral imaging can help better understand the characteristics of
different materials, compared with traditional image systems. However, only
high-resolution multispectral (HrMS) and low-resolution hyperspectral (LrHS)
images can generally be captured at video rate in practice. In this paper, we
propose a model-based deep learning approach for merging an HrMS and LrHS
images to generate a high-resolution hyperspectral (HrHS) image. In specific,
we construct a novel MS/HS fusion model which takes the observation models of
low-resolution images and the low-rankness knowledge along the spectral mode of
HrHS image into consideration. Then we design an iterative algorithm to solve
the model by exploiting the proximal gradient method. And then, by unfolding
the designed algorithm, we construct a deep network, called MS/HS Fusion Net,
with learning the proximal operators and model parameters by convolutional
neural networks. Experimental results on simulated and real data substantiate
the superiority of our method both visually and quantitatively as compared with
state-of-the-art methods along this line of research.Comment: 10 pages, 7 figure
Guided Deep Decoder: Unsupervised Image Pair Fusion
The fusion of input and guidance images that have a tradeoff in their
information (e.g., hyperspectral and RGB image fusion or pansharpening) can be
interpreted as one general problem. However, previous studies applied a
task-specific handcrafted prior and did not address the problems with a unified
approach. To address this limitation, in this study, we propose a guided deep
decoder network as a general prior. The proposed network is composed of an
encoder-decoder network that exploits multi-scale features of a guidance image
and a deep decoder network that generates an output image. The two networks are
connected by feature refinement units to embed the multi-scale features of the
guidance image into the deep decoder network. The proposed network allows the
network parameters to be optimized in an unsupervised way without training
data. Our results show that the proposed network can achieve state-of-the-art
performance in various image fusion problems.Comment: ECCV 202
Unsupervised Sparse Dirichlet-Net for Hyperspectral Image Super-Resolution
In many computer vision applications, obtaining images of high resolution in
both the spatial and spectral domains are equally important. However, due to
hardware limitations, one can only expect to acquire images of high resolution
in either the spatial or spectral domains. This paper focuses on hyperspectral
image super-resolution (HSI-SR), where a hyperspectral image (HSI) with low
spatial resolution (LR) but high spectral resolution is fused with a
multispectral image (MSI) with high spatial resolution (HR) but low spectral
resolution to obtain HR HSI. Existing deep learning-based solutions are all
supervised that would need a large training set and the availability of HR HSI,
which is unrealistic. Here, we make the first attempt to solving the HSI-SR
problem using an unsupervised encoder-decoder architecture that carries the
following uniquenesses. First, it is composed of two encoder-decoder networks,
coupled through a shared decoder, in order to preserve the rich spectral
information from the HSI network. Second, the network encourages the
representations from both modalities to follow a sparse Dirichlet distribution
which naturally incorporates the two physical constraints of HSI and MSI.
Third, the angular difference between representations are minimized in order to
reduce the spectral distortion. We refer to the proposed architecture as
unsupervised Sparse Dirichlet-Net, or uSDN. Extensive experimental results
demonstrate the superior performance of uSDN as compared to the
state-of-the-art.Comment: Accepted by The IEEE Conference on Computer Vision and Pattern
Recognition (CVPR 2018, Spotlight
Model Inspired Autoencoder for Unsupervised Hyperspectral Image Super-Resolution
This paper focuses on hyperspectral image (HSI) super-resolution that aims to
fuse a low-spatial-resolution HSI and a high-spatial-resolution multispectral
image to form a high-spatial-resolution HSI (HR-HSI). Existing deep
learning-based approaches are mostly supervised that rely on a large number of
labeled training samples, which is unrealistic. The commonly used model-based
approaches are unsupervised and flexible but rely on hand-craft priors.
Inspired by the specific properties of model, we make the first attempt to
design a model inspired deep network for HSI super-resolution in an
unsupervised manner. This approach consists of an implicit autoencoder network
built on the target HR-HSI that treats each pixel as an individual sample. The
nonnegative matrix factorization (NMF) of the target HR-HSI is integrated into
the autoencoder network, where the two NMF parts, spectral and spatial
matrices, are treated as decoder parameters and hidden outputs respectively. In
the encoding stage, we present a pixel-wise fusion model to estimate hidden
outputs directly, and then reformulate and unfold the model's algorithm to form
the encoder network. With the specific architecture, the proposed network is
similar to a manifold prior-based model, and can be trained patch by patch
rather than the entire image. Moreover, we propose an additional unsupervised
network to estimate the point spread function and spectral response function.
Experimental results conducted on both synthetic and real datasets demonstrate
the effectiveness of the proposed approach
- …