7 results about "Phase unwrapping" patented technology

The application discloses a phase unwrapping method and device, system and storage medium, comprising: constructing a U-NetHD absolute phase generation network for directly mapping the wrapped phase to the unwrapped phase; constructing a wrapped phase dataset; training the U-NetHD network by using an unwrapped dataset, unwrapping the interference phase through the absolute phase generation network to obtain an initial unwrapped phase; re-wrapping the initial unwrapped phase and performing conjugate multiplication with the original interference phase to obtain a residual phase; unwrapping the residual phase through an L1 norm unwrapping method to obtain a residual unwrapped phase; and finally, summing the initial unwrapped phase and the residual unwrapped phase to obtain the final unwrapped phase. The technical scheme of the application can solve the problem of low unwrapping precision in low coherence and large gradient regions, and effectively improve the phase unwrapping precision.

A phase order correction method for multi-frequency cascaded phase unwrapping is proposed. First, the low-frequency unfolded phase is directly calculated using the multi-frequency fringe method, and then the mid-frequency unfolded phase is obtained to acquire the initial fringe order obtained through a small frequency ratio. Subsequently, based on the shifting wrapped phase method, a fringe order misaligned by half a cycle from the initial fringe order is obtained. Accurate phase reconstruction is achieved through fringe order correction. These two methods complement each other to simultaneously address the accuracy degradation caused by pseudo-2-step transitions and impulse noise errors, while preserving phase map details. This invention obtains the correct order corresponding to the high-frequency wrapped phase through a phase recovery method at two fringe frequencies, and uses this to calculate the high-frequency unfolded phase, achieving fast and accurate phase unwrapping.

The application provides a point cloud reconstruction method based on partition phase unwrapping overcoming misalignment restriction, and relates to the technical field of structured light three-dimensional measurement, and comprises the following steps: synchronously collecting a left image set and a right image set by using a binocular camera, respectively solving a stripe order, a reference wrapped phase and a mask image; determining a first type of crossing point and a second type of crossing point according to the reference wrapped phase; constructing three misaligned wrapped phases with the reference wrapped phase as an intermediate phase, and classifying and calculating the absolute phase in the stripe order according to the number of the first type of crossing point and the second type of crossing point corresponding to each stripe order value; correcting misaligned points for each row of absolute phase by using RANSAC linear fitting; sliding a preset matching window on the left phase image and the right phase image pixel by pixel, combining a full-field illumination image, obtaining a disparity map of the left phase image and the right phase image, and further reconstructing a three-dimensional point cloud. The application can significantly reduce the problems of flying points and phase jumps, and effectively improve the point cloud reconstruction quality.

The application provides a multi-baseline phase unwrapping method based on accurate intercept correction, and relates to the technical field of radar signal processing, and comprises the following steps: acquiring parameter information corresponding to main and auxiliary images of an interferometric synthetic aperture radar in an observation scene and original interferometric phases, and constructing a reference intercept vector based on the parameter information and an external digital elevation model database; traversing actual intercepts corresponding to all pixels in the observation scene through a sliding window, obtaining a core intercept based on the frequency of the actual intercepts, correcting the core intercept by using the reference intercept vector, and obtaining a corrected intercept set; calculating a fuzzy number by using a limited range search method or a Chinese remainder theorem method based on the corrected intercept set and the number of baselines to obtain a fuzzy value; and calculating an unwrapped phase corresponding to each baseline by using a phase unwrapping equation based on the fuzzy value and the original interferometric phases. In this way, the practicability and reliability of the multi-baseline phase unwrapping method are significantly improved.

This invention relates to the field of digital holographic imaging technology, and discloses a fast phase wrapping and unwrapping method, apparatus, and electronic device. The invention includes: digitally reconstructing holographic image data to obtain intensity distribution data and wrapped phase distribution data; calculating weight values ​​at each corresponding pixel position of the intensity and wrapped phase distribution data to generate a weight matrix, where the weight values ​​characterize the reliability of the corresponding pixel's phase data; performing threshold segmentation on the weight matrix to generate a mask, dividing the image region into reliable and unreliable regions; using the weight values ​​of the reliable regions in the mask as the unwrapping order, performing path unwrapping on the wrapped phase distribution data to obtain preliminary unwrapped phase distribution data; using the preliminary unwrapped phase distribution data as initial values, iteratively optimizing using the weight matrix to obtain the final unwrapped phase distribution data. This invention can effectively eliminate the influence of isolated regions on the phase reconstruction accuracy while ensuring unwrapping speed.

The application provides a fast phase unwrapping method based on tail non-convex regularization, and aims at solving the following two technical problems of the existing phase unwrapping algorithm: one is that details are lost due to the discontinuity of the image edge; and the other is that it is difficult to accurately realize phase unwrapping when facing high complexity or large phase jumps. The steps of the application are as follows: based on the wrapped image, a non-convex tail optimization model with box constraint is constructed; the non-convex tail optimization model is solved by using a completely split primal-dual algorithm under the condition that the support set is empty, so that an initial phase is obtained; errors in the initial phase estimation are corrected through tail minimization, and the support set is dynamically updated, so that an unwrapped image is obtained. Compared with the traditional phase unwrapping algorithm, the application combines the non-convex regularization with the tail minimization strategy, so that the accuracy and robustness of the phase unwrapping are improved, and the application has significant superiority in key evaluation indexes such as signal-to-noise ratio and structural similarity.

This invention discloses an adaptive multi-ring network InSAR phase unwrapping method and apparatus, relating to the field of interferometric synthetic aperture radar measurement technology. The method includes: acquiring interferometric phase maps and topographic maps of complex terrain regions; calculating coherence, terrain gradient maps, phase gradient standard deviation, and residual density based on the interferometric phase maps and topographic maps; constructing a multi-ring network by dynamically selecting ring sizes through a decision function based on coherence, terrain gradient maps, phase gradient standard deviation, and residual density; determining the connectivity of the multi-ring network according to a bridging strategy and connectivity detection method, and outputting a globally connected network; performing hierarchical residual optimization using a two-layer strategy of local absorption and global planning based on the globally connected network, and outputting the optimized residuals; and unwrapping all rings in the globally connected network using a strategy of local unwrapping within the rings and global optimization, and outputting the unwrapping results. This invention can solve the network connectivity problem in complex regions.