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Computationally efficient method for retrieval of atmospherically distorted astronomical images

Arun Surya, Swapan K. Saha
2014 Journal of Optics (India)  
We have developed both Direct Bispectrum and Radon transform based Tomographic speckle masking algorithms to retrieve atmospherically distorted astronomical images.  ...  Speckle Imaging based on triple correlation is a very efficient image reconstruction technique which is used to retrieve Fourier phase information of the object in presence of atmospheric turbulence.  ...  The retrieved Fourier phase from bispectrum is combined with Fourier amplitude from speckle interferometry to reconstruct the object.  ... 
doi:10.1007/s12596-014-0196-7 fatcat:5o3nhxl65rcrhcmqtalvpvnwyi

Image encryption using separable amplitude-based virtual image and iteratively retrieved phase information

Hsuan T. Chang
2001 Optical Engineering: The Journal of SPIE  
The plain image, in fact, is encrypted by a separate phase function, which is iteratively retrieved by using the plain image, an arbitrary virtual image, and another fixed random phase function.  ...  Two types of the cryptosystem are proposed such that the separate phase function can be located in either the input plane or the Fourier plane in a 4 correlator.  ...  The phase retrieval algorithm produces the phase mask at the spatial-frequency domain (i.e., the Fourier plane) with constraints via Fourier transform methods.  ... 
doi:10.1117/1.1402124 fatcat:dn7rc6vzmnbcvlb4trvqd4ql3a

Optical encryption method using toroidal zone plates

John Fredy Barrera, Rodrigo Henao, Roberto Torroba
2005 Optics Communications  
In the encryption process we use an optical processor where this phase mask is placed in the Fourier plane of the object to be encrypted.  ...  The optical security system is based on a computer generated phase mask. In particular, for this proposal the selected phase mask is a toroidal zone plate.  ...  Acknowledgements The grants from CONICET (PICT Nr. 008/ 98), from Universidad Nacional de La Plata and CODI-Universidad de Antioquia are gratefully acknowledged.  ... 
doi:10.1016/j.optcom.2004.11.086 fatcat:a27vbl3pzfbkvg6qzl6iaz6hda

Terahertz imaging with compressed sensing and phase retrieval

Wai Lam Chan, Matthew L. Moravec, Richard G. Baraniuk, Daniel M. Mittleman
2008 Optics Letters  
We describe a new terahertz imaging method for high-speed image acquisition using a compressed sensing phase retrieval algorithm.  ...  This technique permits image reconstruction using a limited and randomly chosen subset of a Fourier image.  ...  particular, the fact that a randomly selected subset of the image data is adequate for image reconstruction is a significant advantage, because it means that a fixed collection of randomly generated masks  ... 
doi:10.1364/ol.33.000974 pmid:18451957 fatcat:sjfsqddfcbe6lhhyba7rcxcoea

Terahertz imaging with compressed sensing and phase retrieval

Wai Lam Chan, Matthew L. Moravec, Richard G. Baraniuk, Daniel M. Mittleman
2007 2007 Conference on Lasers and Electro-Optics (CLEO)  
We describe a new terahertz imaging method for high-speed image acquisition using a compressed sensing phase retrieval algorithm.  ...  This technique permits image reconstruction using a limited and randomly chosen subset of a Fourier image.  ...  particular, the fact that a randomly selected subset of the image data is adequate for image reconstruction is a significant advantage, because it means that a fixed collection of randomly generated masks  ... 
doi:10.1109/cleo.2007.4452877 fatcat:ght6aoidxvgslawwykwd4tc5ry

A Novel Image Encryption Scheme Based on Single Random Phase Encoding and Chaos

Yonggang Su, Chen Tang, Zhenkun Lei, Zhaoyi Wang
2018 DEStech Transactions on Computer Science and Engineering  
In the proposed scheme, the random phase mask is generated by Henon map, and the chaos parameters of Henon map can replace the whole phase mask to serve as the secret keys.  ...  Additionally, the proposed scheme contains only one random phase mask, which makes it more efficient and concise to implement.  ...  After that, the transformed image is multiplied by the chaotic random phase mask (CRPM), and then is inverse Fourier transformed to generate the encrypted image.  ... 
doi:10.12783/dtcse/icmsie2017/18674 fatcat:lpfgyfmojrflncxd224ff55ecm

Phase retrieval from multiple binary masks generated speckle patterns

Hai Gong, Paolo Pozzi, Oleg Soloviev, Michel Verhaegen, Gleb Vdovin, Francis Berghmans, Anna G. Mignani
2016 Optical Sensing and Detection IV  
Numerical experiments show the feasibility of this phase retrieval method and the importance of sparse binary masks in the improving of convergence speed.  ...  We present a reference-less and time-multiplexing phase retrieval method by making use of the digital micromirror device (DMD).  ...  This new field is Fourier transformed, Figure 3 3 Phase retrieval with multiple binary masksFor a given total number of frames n, there are 4096/n micromirrors in the 'on' state in each frame.  ... 
doi:10.1117/12.2228297 fatcat:k4iwn4l4lvd67jikownv7fcy7i

Fourier-Domain Fixed Point Algorithms with Coded Diffraction Patterns [article]

Albert Fannjiang
2016 arXiv   pre-print
Fourier-domain Difference Map (FDM) for phase retrieval with two oversampled coded diffraction patterns are proposed.  ...  For generic complex objects without any object constraint, FDM yields a unique fixed point, after proper projection back to the object domain, which is the true solution to the phase retrieval problem  ...  Accordingly, let Φ be the oversampled discrete Fourier transform from N to L such that Φ * Φ = I. In other words, Φ is an isometry and has orthonormal columns.  ... 
arXiv:1406.2742v2 fatcat:b6wcpjnhgjexxmnlvek5qnk5gu

Phase Retrieval: An Overview of Recent Developments [article]

Kishore Jaganathan, Yonina C. Eldar, Babak Hassibi
2015 arXiv   pre-print
The problem of phase retrieval is a classic one in optics and arises when one is interested in recovering an unknown signal from the magnitude (intensity) of its Fourier transform.  ...  , masks, structured illuminations).  ...  Mordechai Segev and Oren Cohen for introducing them to the STFT phase retrieval problem, and for many insightful discussions regarding phase retrieval and optics.  ... 
arXiv:1510.07713v1 fatcat:l2pfboj4jjhjrkvjjaxcfuxhka

Fourier Phase Retrieval: Uniqueness and Algorithms [article]

Tamir Bendory, Robert Beinert, Yonina C. Eldar
2017 arXiv   pre-print
The problem of recovering a signal from its phaseless Fourier transform measurements, called Fourier phase retrieval, arises in many applications in engineering and science.  ...  Fourier phase retrieval poses fundamental theoretical and algorithmic challenges.  ...  Introduction The task of recovering a signal from its Fourier transform magnitude, called Fourier phase retrieval, arises in many areas in engineering and science.  ... 
arXiv:1705.09590v3 fatcat:i3arbexpqra47cp6ggi2w4rpzu

Designing and using prior knowledge for phase retrieval [article]

Eliyahu Osherovich, Michael Zibulevsky, Irad Yavneh
2012 arXiv   pre-print
Quite surprisingly, this can be explained using our previous results on phase retrieval with approximately known Fourier phase.  ...  In this work we develop an algorithm for signal reconstruction from the magnitude of its Fourier transform in a situation where some (non-zero) parts of the sought signal are known.  ...  Introduction The phase retrieval problem amounts to signal reconstruction from the magnitude of its Fourier transform.  ... 
arXiv:1203.0879v1 fatcat:s6xc6fulyjdurgzc3h7int63ii

A cascaded iterative Fourier transform algorithm for optical security applications

Guohai Situ, Jingjuan Zhang
2003 Optik (Stuttgart)  
A cascaded iterative Fourier transform (CIFT) algorithm is presented for optical security applications.  ...  Two phase-masks are designed and located in the input and the Fourier domains of a 4-f correlator respectively, in order to implement the optical encryption or authenticity verification.  ...  The cascaded iteration Fourier transform (CIFT) algorithm begins with the initialization of the phase-distributions of the masks.  ... 
doi:10.1078/0030-4026-00291 fatcat:ywmg5gs4arhuxiicytyqekcchi

Phaseless super-resolution using masks

Kishore Jaganathan, James Saunderson, Maryam Fazei, Yonina C. Eldar, Babak Hassibi
2016 2016 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)  
Phase Retrieval • In several measurement systems, the magnitude-square of the Fourier transform is the measurable quantity Figure: X-ray imaging • Phase retrieval: Recovering a signal from its Fourier  ...  Inspiration from recent work by Bahmani and Romberg on phase retrieval from random measurements b[m] = trace( c m c m AXA ) Super-resolution: Recovering a sparse signal from low-frequency Fourier measurements  ... 
doi:10.1109/icassp.2016.7472436 dblp:conf/icassp/JaganathanSFEH16 fatcat:xmvzuk6nybaebmzfhe4llobnim

Enhanced Optical Image Verification Based on Joint Transform Correlator Adopting Fourier Hologram

Hsuan T. Chang, Ching T. T. Chen
2004 Optical Review  
First, an input phase-only function is Fourier transformed and then interferes with a reference wave that is diffracted from a plane wave incident on another random phase mask.  ...  Second, two phase-only functions are placed at the two input sides of a beamsplitter such that the interference pattern of their Fourier transforms can be detected.  ...  With the inverse Fourier transform of H 1,k (f x , f y ) and applying the input plane constraint, the newly retrieved phase h 1,k+1 (x, y) can be obtained. 11.  ... 
doi:10.1007/s10-043-0045-5 fatcat:fkbzphwfavedvh3gobvaezqr5m

EUV mask feature reconstruction via phase retrieval

Paolo Ansuinelli, Wim Coene, Paul Urbach, André-Jean Attias, Balaji Panchapakesan
2019 Nanoengineering: Fabrication, Properties, Optics, Thin Films, and Devices XVI  
In this work, we perform a simulation study to assess the performance of coherent diffractive imaging (CDI) and related phase retrieval methods for the reconstruction of non-trivially shaped and a-periodic  ...  nanostructures from far field intensity data.  ...  The authors acknowledge financial support from the European Union's Horizon 2020 research and innovation program under the Marie Sk lodowska-Curie Grant Agreement No. 675745.  ... 
doi:10.1117/12.2525976 fatcat:hrubfvxltzfgpluyuoy4c52dm4
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