Results 131 to 140 of about 13,178 (146)

Undersampled digital holographic interferometry

SPIE Proceedings, 2008
In digital holography, primary holographic fringes are recorded using a matricial CCD sensor. Because of the low spatial resolution of currently available CCD arrays, the angle between the reference and object beams must be limited to a few degrees.
Vukičević, Dalibor, Sović, Ivica, Demoli, Nazif, Šariri, Kristina   +3 more
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Dislaying undersampled imagery

Optical Engineering, 1994
Standard digital video displays use 640 x 480 (NTSC) or 512 x 512 (PAL) pixels to display a full screen image, while observers searching such images for small targets (or reading text) will typically operate with a screen subtense of 25 x 35 deg. Often, however, the region of interest in these images may be about 100 x 100 pixels in size, and so ...
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Incremental Hashing with Undersampling

2019 IEEE International Conference on Systems, Man and Cybernetics (SMC), 2019
Most of current hashing methods are proposed based on the assumption that the database is stationary. However, this assumption is not always true as the data environment is sometimes non-stationary. When new images being added to the database, data distributions of existing classes may change and new classes may also appear which result in concept ...
Xiaoxia Jiang, Wing W.Y. Ng, Xing Tian, Sam Kwong, Hui Wang   +4 more
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Transponder with undersampling method

2009 3rd IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications, 2009
A transponder can encode the signal transmitted by synthetic aperture radar (SAR). The reflected signal from the encoding transponder to SAR can be imaged with the background clutters suppressed. One type of encoding transponder inverts the chirp slope of a linear frequency modulation (LFM) signal transmitted by the SAR.
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Unaliasing of undersampled spectra

2016 5th Mediterranean Conference on Embedded Computing (MECO), 2016
One of parts of digital signal processing is processing with undersampling. In this case, the sampling frequency is lower, than it is required by the sampling theorem. At undersampling, the spectrum of signals is distorted by an aliasing. Various ways of correction of the arising distortions are known. These ways are known under the name the unaliasing.
V. Lesnikov, T. Naumovich, A. Chastikov, D. Garsh   +3 more
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Complex pupil retrieval with undersampled data

Journal of the Optical Society of America A, 2009
The ability to retrieve the complex-valued, generalized pupil function of an imaging system from undersampled measurements of the defocused system point spread function (PSF) is examined through numerical simulations. The ability to do so degrades as the detector pixel pitch increases when using a fixed number of PSF measurements.
Samuel T, Thurman, James R, Fienup
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Depth Map Restoration From Undersampled Data

IEEE Transactions on Image Processing, 2017
Depth map sensed by low-cost active sensor is often limited in resolution, whereas depth information achieved from structure from motion or sparse depth scanning techniques may result in a sparse point cloud. Achieving a high-resolution (HR) depth map from a low resolution (LR) depth map or densely reconstructing a sparse non-uniformly sampled depth ...
Srimanta Mandal, Arnav Bhavsar, Anil Kumar Sao   +2 more
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Gabor transform with undersampling

Proceedings of Third International Symposium on Time-Frequency and Time-Scale Analysis (TFTS-96), 2002
We investigate discrete Gabor transforms with undersampling. For an undersampled Gabor triple (g,a,b) (i.e.,a.b>N), we show that the associated generalized dual Gabor wavelet is the same as the one associated to (g,b/spl tilde/,a/spl tilde/), except for the redundancy constant factor.
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Undersampled omnidirectional ultrasonic flow detector

The Journal of the Acoustical Society of America, 1999
A motion detection scheme is described which periodically sends a plurality of pulsed ultrasonic signals from a transducer to a particular range cell to receive a series of backscattered signals from the particular range cell. The time interval between any two pulses is greater than a largest dimension of the range cell divided by a slowest velocity of
Peter G. Webb, Hewlett E. Melton
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Radial-based undersampling approach with adaptive undersampling ratio determination

Neurocomputing, 2023
Bo Sun, Qian Zhou, Zhijun Wang, Peng Lan, Yunsheng Song, Shaomin Mu, Aifeng Li, Haiyan Chen, Peng Liu   +8 more
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