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Analyzing spatially-varying blur

Ayan Chakrabarti, Todd Zickler, William T. Freeman
2010 2010 IEEE Computer Society Conference on Computer Vision and Pattern Recognition  
Blur is caused by a pixel receiving light from multiple scene points, and in many cases, such as object motion, the induced blur varies spatially across the image plane.  ...  This work considers such blur and makes two contributions: a local blur cue that measures the likelihood of a small neighborhood being blurred by a candidate blur kernel; and an algorithm that, given an  ...  ., and by a fellowship from the Alfred P. Sloan Foundation. WF was supported by NGA NEGI-1582-04-0004, MURI Grant N00014-06-1-0734, and gifts from Microsoft, Google, and Adobe.  ... 
doi:10.1109/cvpr.2010.5539954 dblp:conf/cvpr/ChakrabartiZF10 fatcat:j2gogvhcknapjafy4elqharuni

Deep Model-Based Super-Resolution with Non-uniform Blur [article]

Charles Laroche and Andrés Almansa and Matias Tassano
2022 arXiv   pre-print
We propose a state-of-the-art method for super-resolution with non-uniform blur.  ...  Despite their impressive performance, existing techniques usually assume a uniform blur kernel. Hence, these techniques do not generalize well to the more general case of non-uniform blur.  ...  Early approaches decompose the spatially-varying blur into a finite basis of spatially-uniform blur kernels and their respective spatially-varying weights [41] .  ... 
arXiv:2204.10109v2 fatcat:wbpsfhqptre3ld6agpdjcunyky

Model-based iterative reconstruction for flat-panel cone-beam CT with focal spot blur, detector blur, and correlated noise

Steven Tilley, Jeffrey H Siewerdsen, J Webster Stayman
2015 Physics in Medicine and Biology  
For example, for a system with 0.34 mm FWHM scintillator blur and 0.70 FWHM focal spot blur, using the a correlated noise model instead of an uncorrelated noise model increased resolution by 42% (with  ...  While this advantage holds across a wide range of systems with differing blur characteristics, the improvements are greatest for systems where source blur is larger than detector blur.  ...  ACKNOWLEDGEMENTS This work supported in part by NIH grants R21EB014964, T32EB010021, R01EB018896, and an academic-industry partnership with Varian Medical Systems (Palo Alto, CA).  ... 
doi:10.1088/0031-9155/61/1/296 pmid:26649783 pmcid:PMC5011041 fatcat:5h4mw3q44vfl3fwztxuh5ok35m

SABER: A Systems Approach to Blur Estimation and Reduction in X-ray Imaging [article]

K. Aditya Mohan, Robert M. Panas, Jefferson A. Cuadra
2020 arXiv   pre-print
Blur in X-ray radiographs not only reduces the sharpness of image edges but also reduces the overall contrast.  ...  In particular, we model the combined contribution of X-ray source and detector blurs while assuming negligible contribution from other forms of blur.  ...  LDRD funding with tracking numbers 16-ERD-006 and 19-ERD-022 were used for this project. We thank Kyle Champley from LLNL for useful discussions.  ... 
arXiv:1905.03935v2 fatcat:ldyodkwyivdybak3crngizq4bm

BaMBNet: A Blur-aware Multi-branch Network for Defocus Deblurring [article]

Pengwei Liang, Junjun Jiang, Xianming Liu, Jiayi Ma
2021 arXiv   pre-print
Moreover, we introduce a meta-learning defocus mask generation algorithm to assign each pixel to a proper branch.  ...  To this end, this study designs a novel blur-aware multi-branch network (BaMBNet), in which different regions (with different blur amounts) should be treated differentially.  ...  As a result, the formed left and right views are very close, i.e. the character 'C' is clear, which is the same as the imaging results of a traditional non-DP camera.  ... 
arXiv:2105.14766v1 fatcat:ll44nsmjyzbndh42j76drafjsy

SABER: A Systems Approach to Blur Estimation and Reduction in X-ray Imaging

K. Aditya Mohan, Robert M. Panas, Jefferson A. Cuadra
2020 IEEE Transactions on Image Processing  
Blur in X-ray radiographs not only reduces the sharpness of image edges but also reduces the overall contrast.  ...  In particular, we model the combined contribution of X-ray source and detector blurs while assuming negligible contribution from other forms of blur.  ...  This document was prepared as an account of work sponsored by an agency of the United States government.  ... 
doi:10.1109/tip.2020.3006339 fatcat:roxmq7ogurbtjaq74ggovu6mg4

Blind deconvolution of Gaussian blurred images containing additive white Gaussian noise

P. E. Robinson, Y. Roodt
2013 2013 IEEE International Conference on Industrial Technology (ICIT)  
This paper makes use of a novel blur identification technique and a noise identification technique to perform blind deconvolution on single images that have been degraded by a Gaussian blur and contain  ...  These algorithms generally assume that knowledge of the nature of the distortion and noise contained in an observed image is available.  ...  This demonstrates the ability of the algorithm to be effective even when faced with a complex image with a non-uniform blur and still be able to reconstruct the high-frequency content of the image resulting  ... 
doi:10.1109/icit.2013.6505824 fatcat:nbfdpfn7ivfu5l6dlqktcadpqi

Joint coding of shape and blur in area V4

Timothy D. Oleskiw, Amy Nowack, Anitha Pasupathy
2018 Nature Communications  
Edge blur, a prevalent feature of natural images, is believed to facilitate multiple visual processes including segmentation and depth perception.  ...  was increased. b, c Two additional examples that also exhibited a monotonic decrease in responses with increasing blur.  ...  Elder for helpful discussions and comments on the manuscript and A. Fyall for assistance with animal training and data collection.  ... 
doi:10.1038/s41467-017-02438-8 pmid:29386511 pmcid:PMC5792439 fatcat:eh6b7bikl5fnrnld46nuvsvzc4

Parametric Blur Estimation for Blind Restoration of Natural Images: Linear Motion and Out-of-Focus

Joao P. Oliveira, Mario A. T. Figueiredo, Jose M. Bioucas-Dias
2014 IEEE Transactions on Image Processing  
This paper presents a new method to estimate the parameters of two types of blurs, linear uniform motion (approximated by a line characterized by angle and length) and out-of-focus (modeled as a uniform  ...  The accuracy of the proposed method is validated by simulations, and the effectiveness of the proposed method is assessed by testing the algorithm on real natural blurred images and comparing it with state-of-the-art  ...  By using the fitting function γ (ρ) (10) , the method is no longer dependent on the location of the first local minimum, and can also achieve sub-pixel precision.  ... 
doi:10.1109/tip.2013.2286328 pmid:24144664 fatcat:ra73kok56za4tiojtlagwmlm5m

Computational aberration compensation by coded-aperture-based correction of aberration obtained from optical Fourier coding and blur estimation

Jaebum Chung, Gloria W. Martinez, Karen C. Lencioni, Srinivas R. Sadda, Changhuei Yang
2019 Optica  
We report the demonstration of CACAO-FB with a variety of samples including an in vivo imaging experiment on the eye of a rhesus macaque to correct for its inherent aberration in the rendered retinal images  ...  We report a novel generalized optical measurement system and computational approach to determine and correct aberrations in optical systems.  ...  Furthermore, non-uniform specular reflections from the retina add noise to part of the captured data, leading to sub-optimal latent image recovery by the CACAO-FB algorithm pipeline.  ... 
doi:10.1364/optica.6.000647 pmid:33134437 pmcid:PMC7597901 fatcat:dksjmqjq7vgvhgv3ltbq35uioe

Measurement of the point-spread function of a noisy imaging system

Christopher D. Claxton, Richard C. Staunton
2007 Optical Society of America. Journal A: Optics, Image Science, and Vision  
The paper compares several mathematical models of the PSF and presents an improved measurement technique that enabled sub-pixel estimation of 2-D functions.  ...  The PSF was computed from an ensemble of edge spread function measurements.  ...  The ESF, assuming a step edge with non-uniform illumination and a Generalized Gaussian PSF, is given by the convolution of (11) with (13) .  ... 
doi:10.1364/josaa.25.000159 pmid:18157223 fatcat:uglandv6j5eh5lti36h7bwajhu

Iterative Blind Deconvolution Algorithm for Deblurring a Single PSP/TSP Image of Rotating Surfaces

Anshuman Pandey, James Gregory
2018 Sensors  
The scheme estimates a super-resolved spatially varying blur kernel with sub-pixel resolution without filtering the blurred image, and then restores the image using classical iterative regularization tools  ...  of the blade edges.  ...  Kyle Hird provided help with the computational work. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s18093075 pmid:30217038 pmcid:PMC6163952 fatcat:4jva2tnq55hfpi2qrk3ljxawpm

Blind restoration for nonuniform aerial images using nonlocal Retinex model and shearlet-based higher-order regularization

Rui Chen, Huizhu Jia, Xiaodong Xie, Wen Gao
2017 Journal of Electronic Imaging (JEI)  
To recover high-quality aerial image from its non-uniform version, we propose a novel patch-wise restoration approach based on a key observation that the degree of blurring is inevitably affected by the  ...  And then non-uniform coupled blurring in the enhanced reflectance image is alleviated and transformed towards uniform distribution, which will facilitate the subsequent deblurring.  ...  U st ≤ r r r (7) The closed-form solution for can be found with the standard optimization method.  ... 
doi:10.1117/1.jei.26.3.033016 fatcat:6itkkvmobfeubgs5ydtj3k2sly

Model-based least squares optimal interpolation

A. Gilman, D.G. Bailey, S. Marsland
2009 2009 24th International Conference Image and Vision Computing New Zealand  
In this paper we consider and derive a finite-support interpolation kernel based on a step-edge model and show that this results in a piece-wise cubic polynomial similar to Keys' cubic convolution.  ...  We offer an experimental comparison of the proposed kernel to a number of common methods and show that it performs similar to, or better than, the existing methods with similar extent of spatial support  ...  Figure 2 2 Input and output pixels within the filter window sampling a blurred step-edge located at p=1.2. -edge M(x;p), centred at x = ; M m p .  ... 
doi:10.1109/ivcnz.2009.5378424 fatcat:sghtsvthffgnhowyzoqsqiqlha

Experimentally Validated Simulations of 50 μm X-ray PIV Tracer Particles [article]

Jason T. Parker, Simo A. Mäkiharju
2021 arXiv   pre-print
Nevertheless, the BL approach predicts the system behavior, is computationally inexpensive, and enables the exploration of a vast parameter space for system design.  ...  As predicted by the simulations, the AGSF-33 particles are visible with a SNR greater than unity in 100 ms exposure time images, demonstrating their potential as X-ray PIV or particle tracking velocimetry  ...  The contributions of Angel Rodriguez who helped with the X-ray facility setup are also gratefully recognized.  ... 
arXiv:2109.13470v1 fatcat:enw6rjocmvgm3hd5w3hz47uilu
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