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SPIE Proceedings, 1987
A new approach towards the recognition and removal of the speckle artefact in ultrasound pulse-echo images is presented. The technique utilises the behaviour of the signal's instantaneous frequency, which is the time derivative of the temporal phase. In contrast to all other approaches, the proposed method allows the speckle artefact to be recognised ...
S. Leeman, D. A. Seggie
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A new approach towards the recognition and removal of the speckle artefact in ultrasound pulse-echo images is presented. The technique utilises the behaviour of the signal's instantaneous frequency, which is the time derivative of the temporal phase. In contrast to all other approaches, the proposed method allows the speckle artefact to be recognised ...
S. Leeman, D. A. Seggie
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Partly Polarized Speckles and Speckle Reduction in Interferometry
2008 14th Conference on Microwave Techniques, 2008In this paper we discuss problems in an interferometer which arise when the interferometer uses a conventional, so-called 'non-cooperative' target rather than a mirror. Under these conditions, the reflected light assumes the character of a speckle field which requires that we describe its statistical properties by applying first order statistics of ...
Petr Kucera, Friedemann Mohr
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Assessment of hybrid speckle reduction algorithms
Physics in Medicine and Biology, 1991A consequence of employing coherent detection methods in medical ultrasound imaging systems is the occurrence of interference effects in the received echo field, which produce the speckle artefact. Speckle can severely degrade the information content of the image, and its efficient removal from ultrasound pulse-echo images is the focus of a number of ...
F, Forsberg +3 more
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Speckle Reduction by Double Recorded Holograms
Applied Optics, 1973A method of speckle reduction in holography for 2-D objects with minimum recording area is presented. The image is incoherently synthesized from the hologram double recorded with a set of random phase plates.
M, Kato, Y, Okino
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Speckle-modulation for speckle reduction in optical coherence tomography
Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXII, 2018Optical coherence tomography (OCT) is a powerful biomedical imaging technology that relies on the coherent detection of backscattered light to image tissue morphology in vivo. As a consequence, OCT is susceptible to coherent noise, known as speckle noise, which imposes significant limitations on its diagnostic capabilities.
Adam de la Zerda +7 more
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Hadamard speckle contrast reduction
Optics Letters, 2004The condition for a diffuser to produce the maximum speckle contrast reduction with the minimum number of distinct phase patterns is derived. A binary realization of this optimum diffuser is obtained by mapping the rows or columns of a Hadamard matrix to the phase patterns.
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A laser speckle reduction system
SPIE Proceedings, 2011Speckle degrades the contrast of the fringe patterns in laser interferometers that measure rough objects. In this paper, we describe a speckle reduction system that can be used with high speed cameras to increase the frame rates of the interferometer and creates less vibration in the system.
Joshua M. Cobb, Paul Michaloski
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Speckle reduction with edge-preserving
1997 IEEE International Conference on Acoustics, Speech, and Signal Processing, 2002Coherent imagery emerges as one of the major domains in image processing and includes topics as diversified as radar, medical and surface analysis. Whatever the application, the resulting image is noisy corrupted. In coherent imaging, images suffer from speckle noise, whose main characteristic is to be multiplicative.
P. Mathieu +3 more
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Geometric filter for speckle reduction
Applied Optics, 1985An algorithm is described which reduces speckle noise in images. It is a nonlinear algorithm based on geometric concepts. Tests were performed on synthetic aperture radar images which show that it compares favorably with a 3 × 3 median filter.
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Phase diversity for speckle reduction
SPIE Proceedings, 2003B-mode ultrasound images are characterized by speckle artefact, which results from interference effects between returning echoes, and may make the interpretation of images difficult. Consequently, many methods have been developed to reduce this problematic feature.
Ricardo G. Dantas +4 more
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