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Robust sub-pixel disparity estimation and its refinement around depth discontinuity and featureless areas

Hongshi Yan, Jian-Guo Liu
2010 2010 IEEE International Geoscience and Remote Sensing Symposium  
In addition, while our robust phase correlation based disparity estimation algorithm is good at sub-pixel disparity measurement it is not capable of stereo matching for large disparity which is the usual  ...  The disparity measurement is then further improved to sub-pixel accuracy for each corresponding point through the proposed enhanced robust phase correlation based disparity estimation technique at the  ... 
doi:10.1109/igarss.2010.5652314 dblp:conf/igarss/YanL10 fatcat:jw4lxu44y5gndb6ehzt7w3dl2y

Disparity from Monogenic Phase [chapter]

Michael Felsberg
2002 Lecture Notes in Computer Science  
Disparity estimation is a fundamental problem of computer vision. Besides other approaches, disparity estimation from phase information is a quite wide-spread technique.  ...  In the present paper, we have considered the influence of the involved quadrature filters and we have replaced them with filters based on the monogenic signal.  ...  from Phase The disparity can be estimated by various methods, e.g. correlation based techniques, feature based techniques, and phase based techniques [3, 4] .  ... 
doi:10.1007/3-540-45783-6_30 fatcat:vx5rserpqzd2dircxymcccsgme

Absolute three-dimensional shape measurement using coded fringe patterns without phase unwrapping or projector calibration

William Lohry, Vincent Chen, Song Zhang
2014 Optics Express  
This paper presents a novel stereo-phase-based absolute three-dimensional (3D) shape measurement that requires neither phase unwrapping nor projector calibration.  ...  This proposed method can be divided into two steps: (1) obtain a coarse disparity map from the quality map; and (2) refine the disparity map using wrapped phase.  ...  Lastly, since the traditional DFP-based method recovers 3D geometry directly from the phase, the phase quality is essential to measurement accuracy: any noise or distortion on the phase will be reflected  ... 
doi:10.1364/oe.22.001287 pmid:24515134 fatcat:rmborcjyujbdvbnada3hu7qd54

Page 1634 of Neural Computation Vol. 8, Issue 8 [page]

1996 Neural Computation  
Rather, we mean that their disparity tuning curves change dramatically when the same type of stimuli with different Fourier phases are used in the measurements (see Fig. 2).  ...  We concluded based on these results that the mere existence of (approximate) CDs in real cells cannot be used to distinguish the phase-parameter-based RF description from the traditional position- shift-based  ... 

Comparing Some Tools Useing Frequency Domain for the Estimation of 1-d (and 2-d) Disparity

Yann Yvinec, Bernard Thiesse
1994 IAPR International Workshop on Machine Vision Applications  
Then a comparison between two strategies is done : an image-based choice of filters and the use of a "complete" subset of filters.  ...  THE USE OF PHASE DERIVATIVE Earlier methods [ l l ] which estimate disparity from phase difference were based on dividing by the filter peak tuning frequency.  ...  Here, the optimal filter is the one minimizing the percentage of wrong disparity measurements. phase tom a Gabor Rlter !  ... 
dblp:conf/mva/YvinecT94 fatcat:32qaixj72zhonclk6euifcl4im

Three-Dimensional Reconstruction of Light Field Based on Phase Similarity

Wei Feng, Junhui Gao, Tong Qu, Shiqi Zhou, Daxing Zhao
2021 Sensors  
Then, the disparity estimation algorithm based on phase similarity was designed to effectively improve the reliability and accuracy of disparity calculation, in which the phase information was used instead  ...  In this paper, a 3D reconstruction method of light field based on phase similarity is proposed to increase the accuracy of depth estimation and the scope of applicability of epipolar plane image (EPI).  ...  The depth information of the measured object could be obtained by substituting the accurate disparity map based on phase similarity into the calibrated linear equation.  ... 
doi:10.3390/s21227734 pmid:34833806 pmcid:PMC8618702 fatcat:s5uz6ns7azcupjhxibovrre7cq

Techniques for disparity measurement

Michael R.M. Jenkin, Allen D. Jepson, John K. Tsotsos
1991 CVGIP: Image Understanding  
Finally, we present a new technique for measuring disparity as the local phase difference between bandpass versions of the two images, and we show how this technique surmounts some of the difficulties  ...  By considering some of the implications of disparity in the frequency domain, we present a new definition of disparity that is tied to the interocular phase difference in bandpass versions of the monocular  ...  base a disparity measurement primitive on the entire output of the spatial-frequency tuned channel.  ... 
doi:10.1016/1049-9660(91)90002-7 fatcat:jay6jpsiffg4rmmextiq3ijlby

FFT-Based Disparity Estimation for Stereo Image Coding [chapter]

Udo Ahlvers, Udo Zoelzer, Stefan Rechmeier
2003 Lecture Notes in Computer Science  
In this paper a new FFT-based algorithm for disparity estimation is proposed. The phase difference between the two images is calculated at several frequencies for each pixel.  ...  The resulting disparity can then be estimated from the gradient of these phase differencies. In the second part, these disparity maps are used for an efficient stereo image coding approach.  ...  Principle of the quality measurement for disparity maps.  ... 
doi:10.1007/978-3-540-45243-0_34 fatcat:cz34jgjmynfhrdccbdjrxl7erm

Parallels between the development of therapeutic drugs and cancer health disparity programs

Kenneth C. Chu, Moon S. Chen, Mark B. Dignan, Emmanuel Taylor, Edward Partridge
2008 Cancer  
Analogously, community-based participatory research is used to develop disparities-reducing interventions (DRIs) within the community.  ...  The preclinical phase of in vitro and in vivo testing is analogous to identifying the disparities in the community. Then clinical testing begins with phase 1, toxicity, and dose-establishing studies.  ...  Cancer Health Disparities Research Drug Development Phases Drug Discovery and Development Stages in Community- based Cancer Health Disparities Research Community-based Activities to Develop  ... 
doi:10.1002/cncr.23879 pmid:18780311 pmcid:PMC4360960 fatcat:pktnbf5bmbguzgqvp43aqkgowu

Three-dimensional absolute shape measurement by combining binary statistical pattern matching with phase-shifting methods

Yatong An, Song Zhang
2017 Applied Optics  
The coarse correspondence map is further refined by using the wrapped phase as a constraint. We then use the refined correspondence map to determine a fringe order for absolute phase unwrapping.  ...  This paper presents a novel method that leverages the stereo geometric relationship between projector and camera for absolute phase unwrapping on a standard one-projector and one-camera structured light  ...  (a) Raw disparity map directly generated from block matching; (b) disparity map after hole filling; (c) refined disparity map based on phase constraint; (d) unwrapped phase from (b); (e) unwrapped phase  ... 
doi:10.1364/ao.56.005418 pmid:29047499 fatcat:fl7hbjfrjfffpfpatoxmxd2ytu

Stereo sensitivity depends on stereo matching

Suzanne P. McKee, Preeti Verghese, Bart Farell
2005 Journal of Vision  
To force observers to make judgments based on carrier disparity, we then varied the interocular phase incrementally from trial-to-trial while keeping edge disparity fixed for a given block of trials.  ...  Stereoacuity thresholds, measured with bar targets, rise as the absolute disparity of the bars is increased.  ...  Our threshold measures for gratings show that sensitivity does not depend on the interocular phase disparity alone. As the Figure 6 .  ... 
doi:10.1167/5.10.3 pmid:16441185 pmcid:PMC1461459 fatcat:stk2ikvug5agfkls3r6oy2qwki

How to "hear" visual disparities: real-time stereoscopic spatial depth analysis using temporal resonance

Bernd Porr, Alex Cozzi, Florentin Wörgötter
1998 Biological cybernetics  
We will compare the results from the temporal resonance algorithm with those obtained from several other techniques like crosscorrelation or spatial phase-based disparity estimation showing that the novel  ...  disparity as local temporal phase dierences between the left and right ®lter responses.  ...  In these area there is no way to measure disparity, and the resonator response slowly fades. The ®lter-based techniques produce results in characteristic`bands' centered Fig. 3 .  ... 
doi:10.1007/s004220050437 pmid:9691262 fatcat:5n2lreirk5g6plvfyyottfgcci

Disparity Using Feature Points in Multi Scale [chapter]

Ilkay Ulusoy, Edwin R. Hancock, Ugur Halici
2002 Lecture Notes in Computer Science  
In this paper we describe a statistical framework for binocular disparity estimation. We use a bank of Gabor filters to compute multiscale phase signatures at detected feature points.  ...  The disparity map is computed using the set of maximum likelihood correspondences. This study is partially supported by TUBITAK BDP and METU AFP 2000.07.04.01  ...  In this paper, disparity is estimated from the region-based phase differences between the left and right images.  ... 
doi:10.1007/3-540-70659-3_33 fatcat:6ybfxygrnzcddftcpu6nhw5nge

A phase-based stereo vision system-on-a-chip

Javier Díaz, Eduardo Ros, Silvio P. Sabatini, Fabio Solari, Sonia Mota
2007 Biosystems (Amsterdam. Print)  
A simple and fast technique for depth estimation based on phase measurement has been adopted for the implementation of a real-time stereo system with sub-pixel resolution on an FPGA device.  ...  The technique avoids the attendant problem of phase warping.  ...  Although from a computational point of view there is no difference between computing disparity from differences of the phase on the monocular images or from a direct measure of the binocular phase difference  ... 
doi:10.1016/j.biosystems.2006.09.028 pmid:17045391 fatcat:pmvdjoe52fdujncmqdy5nvkkxe

Stereoscopic depth perception from oblique phase disparities

Saumil S. Patel, Michael T. Ukwade, Scott B. Stevenson, Harold E. Bedell, Vanitha Sampath, Haluk Ogmen
2003 Vision Research  
In order to understand the role of oblique retinal image disparities in the perception of stereoscopic depth, we measured the depth perceived from random dot stereograms in which phase disparities were  ...  Because the perceived depth from oblique phase disparities is consistent with the trigonometrically determined equivalent horizontal disparities, we presume that the information from oblique phase disparities  ...  Simulation results for an ÔextendedÕ disparity energy model based on phase-disparity computations for stereoscopic depth perception.  ... 
doi:10.1016/s0042-6989(03)00464-4 pmid:13129536 fatcat:x22rbbgk7fh6dh6nzvgahoillu
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