- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2018 26th European Signal Processing Conference (EUSIPCO) - Roma, Italy (2018.9.3-2018.9.7)] 2018 26th European Signal Processing Conference (EUSIPCO) - Spatio-Spectral Multichannel Reconstruction from few Low-Resolution Multispectral Data
摘要： This paper deals with the reconstruction of a 3-D spatio-spectral object observed by a multispectral imaging system, where the original object is blurred with a spectral-variant PSF (Point Spread Function) and integrated over few broad spectral bands. In order to tackle this ill-posed problem, we propose a linear forward model that accounts for direct (or auto) channels and between (or cross) channels degradation, by modeling the imaging system response and the spectral distribution of the object with a piecewise linear function. Reconstruction based on regularization method is proposed, by enforcing spatial and spectral smoothness of the object. We test our approach on simulated data of the Mid-InfraRed Instrument (MIRI) Imager of the James Webb Space Telescope (JWST). Results on simulated multispectral data show a significant improvement over the conventional multichannel method.
关键词： Deconvolution,Image reconstruction,Inverse problems,Multispectral restoration,System modeling
更新于2025-09-23 15:23:52
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Fabrication of 2D thin-film filter-array for compressive sensing spectroscopy
摘要： We demonstrate 2D filter-array compressive sensing spectroscopy based on thin-film technology and a compressive sensing reconstruction algorithm. To obtain different spectral modulations, we fabricate a set of multilayer filters using alternating low- and high-index materials and reconstruct the input spectrum using a small number of measurements. Experimental results show that the fabricated filter-array provides compatible spectral resolution performance with a conventional spectrometer in monochromatic lights and LEDs. In addition, the fabricated filter-array covers a wide range of wavelengths with a single exposure.
关键词： Compressive sensing,Thin films,Spectroscopy,Inverse problems
更新于2025-09-23 15:23:52
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Correlation imaging in inverse scattering is tomography on probability distributions
摘要： Scattering from a non-smooth random field on the time domain is studied for plane waves that propagate simultaneously through the potential in variable angles. We first derive sufficient conditions for stochastic moments of the field to be recovered from empirical correlations between amplitude measurements of the leading singularities, detected in the exterior of a region where the potential is almost surely supported. The result is then applied to show that if two sufficiently regular random fields yield the same correlations, they have identical laws as function-valued random variables.
关键词： random potential,scattering,inverse problems,partial differential equations
更新于2025-09-23 15:23:52
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[IEEE 2018 26th European Signal Processing Conference (EUSIPCO) - Rome (2018.9.3-2018.9.7)] 2018 26th European Signal Processing Conference (EUSIPCO) - Bayesian Restoration of High-Dimensional Photon-Starved Images
摘要： This paper investigates different algorithms to perform image restoration from single-photon measurements corrupted with Poisson noise. The restoration problem is formulated in a Bayesian framework and several state-of-the-art Monte Carlo samplers are considered to estimate the unknown image and quantify its uncertainty. The different samplers are compared through a series of experiments conducted with synthetic images. The results demonstrate the scaling properties of the proposed samplers as the dimensionality of the problem increases and the number of photons decreases. Moreover, our experiments show that for a certain photon budget (i.e., acquisition time of the imaging device), downsampling the observations can yield better reconstruction results.
关键词： Bayesian statistics,Markov chain Monte Carlo,Inverse problems,Image processing,Bouncy particle sampler,Poisson noise
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - Krakow, Poland (2018.10.16-2018.10.18)] 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - A Newton-Conjugate-Gradient Method in L <sup>p</sup> Banach Spaces for Three-Dimensional Microwave Imaging
摘要： Microwave imaging is a diagnostic technique for inspecting dielectric and conducting materials based on electromagnetic scattering. Although usually developed with reference to two-dimensional configurations (tomography), it allows a quite 'natural' extension to three-dimensional targets. In this paper, a full-wave three-dimensional approach is developed. The inverse scattering problem is solved, in a regularized way, by using a Newton-conjugate-gradient method. The main novelty concerns the nonconventional framework in which the approach is developed, i.e., the Lp Banach spaces. The paper describes the mathematical formulation of the method. Moreover, numerical results are reported and discussed in order to assess the capabilities and limitations of the proposed technique.
关键词： Banach spaces,inverse problems,Newton schemes,Imaging techniques,conjugate gradient method,microwaves
更新于2025-09-23 15:22:29
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[IEEE 2018 5th NAFOSTED Conference on Information and Computer Science (NICS) - Ho Chi Minh, Vietnam (2018.11.23-2018.11.24)] 2018 5th NAFOSTED Conference on Information and Computer Science (NICS) - Joint Image Deblurring and Binarization for License Plate Images using Deep Generative Adversarial Networks
摘要： Image deblurring is a highly ill-posed inverse problem where it aims to estimate the sharp image from blurred image with or without the knowledge about the blurring process. Despite the success of model-based image deblurring methods where the deconvolution is a major step to recover the sharp image, its usage in practice is still limited, especially when many factors such as object motion, camera motion, non-uniform sensitivity of the imaging device contribute to imaging process. In automatic license plate recognition (ALPR) of moving vehicle, the blurred image severely reduces the accuracy of recognition. Meanwhile, though the binarized image of license plate has an important role in ALPR systems, its accuracy is largely affected by the blurred image. In this paper, we use a deep architecture based on Generative Adversarial Networks to jointly perform image deblurring and image binarization for license plate images. Our model directly maps from blurred image to binary image without going through the deblurring as in conventional method. The proposed method is benefited from the fact that the ground-truth, sharp license plates are difficult to acquire for moving object, while the accurate binary images can be manually derived from blurred ones.
关键词： Inverse Problems,License Plate Deblurring,Image Deblurring,Generative Adversarial Network (GAN)
更新于2025-09-23 15:22:29
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Maximum entropy based non-negative optoacoustic tomographic image reconstruction
摘要： Objective: Optoacoustic (photoacoustic) tomography is aimed at reconstructing maps of the initial pressure rise induced by the absorption of light pulses in tissue. In practice, due to inaccurate assumptions in the forward model, noise and other experimental factors, the images are often afflicted by artifacts, occasionally manifested as negative values. The aim of the work is to develop an inversion method which reduces the occurrence of negative values and improves the quantitative performance of optoacoustic imaging. Methods: We present a novel method for optoacoustic tomography based on an entropy maximization algorithm, which uses logarithmic regularization for attaining non-negative reconstructions. The reconstruction image quality is further improved using structural prior based fluence correction. Results: We report the performance achieved by the entropy maximization scheme on numerical simulation, experimental phantoms and in-vivo samples. Conclusion: The proposed algorithm demonstrates superior reconstruction performance by delivering non-negative pixel values with no visible distortion of anatomical structures. Significance: Our method can enable quantitative optoacoustic imaging, and has the potential to improve pre-clinical and translational imaging applications.
关键词： inverse problems,image reconstruction,Optical parameters,regularization theory,photoacoustic tomography
更新于2025-09-23 15:22:29
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Inverse Problem in the Theory of Surface Traveling Waves in Layered Media
摘要： The regularization method, in addition to efficiently resolving the issue with ill-posed problems in various applications, also substantially suppresses noise and error propagation. To achieve these goals, the article proposes a new “genetic algorithm” (GA) method, linked with Tikhonov’s regularization method (GA-TRM). The regular operator is introduced in the GA fitness functions to study the inverse problem of surface-wave dispersion. Experimental results have shown that, compared with the classical algorithm, the new algorithm improves inversion accuracy, reduces errors, and lowers inversion instability.
关键词： regularization method,inverse problems,surface waves,dispersion curve,genetic algorithm
更新于2025-09-23 15:21:21
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Spatial Retrieval of Broadband Dielectric Spectra
摘要： A broadband soil dielectric spectra retrieval approach (1 MHz–2 GHz) has been implemented for a layered half space. The inversion kernel consists of a two-port transmission line forward model in the frequency domain and a constitutive material equation based on a power law soil mixture rule (Complex Refractive Index Model—CRIM). The spatially-distributed retrieval of broadband dielectric spectra was achieved with a global optimization approach based on a Shuffled Complex Evolution (SCE) algorithm using the full set of the scattering parameters. For each layer, the broadband dielectric spectra were retrieved with the corresponding parameters thickness, porosity, water saturation and electrical conductivity of the aqueous pore solution. For the validation of the approach, a coaxial transmission line cell measured with a network analyzer was used. The possibilities and limitations of the inverse parameter estimation were numerically analyzed in four scenarios. Expected and retrieved layer thicknesses, soil properties and broadband dielectric spectra in each scenario were in reasonable agreement. Hence, the model is suitable for an estimation of in-homogeneous material parameter distributions. Moreover, the proposed frequency domain approach allows an automatic adaptation of layer number and thickness or regular grids in time and/or space.
关键词： soil measurements,electromagnetic scattering inverse problems,dielectric measurements,modeling,microwave propagation,dielectric materials
更新于2025-09-23 15:21:01
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New Interior Transmission Problem Applied to a Single Floquet-Bloch Mode Imaging of Local Perturbations in Periodic Media
摘要： This paper considers the imaging of local perturbations of an infinite penetrable periodic layer. A cell of this periodic layer consists of several bounded inhomogeneities situated in a known homogeneous media. We use a differential linear sampling method to reconstruct the support of perturbations without using the Green’s function of the periodic layer nor reconstruct the periodic background inhomogeneities. The justification of this imaging method relies on the well-posedeness of a nonstandard interior transmission problem, which until now was an open problem except for the special case when the local perturbation did not intersect the background inhomogeneities. The analysis of this new interior transmission problem is the main focus of this paper. We then complete the justification of our inversion method and present some numerical examples that confirm the theoretical behavior of the differential indicator function determining the reconstructable regions in the periodic layer.
关键词： Local Perturbations,Imaging,Floquet-Bloch Mode,Inverse Problems,Interior Transmission Problem,Periodic Media
更新于2025-09-23 15:21:01