- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2018 China International SAR Symposium (CISS) - Shanghai (2018.10.10-2018.10.12)] 2018 China International SAR Symposium (CISS) - A Phase Reconstruction Method for Ground-Based Interferometric SAR
摘要： Ground-based interferometric SAR (GB-InSAR) technology is becoming an important terrain mapping technology as it has the characteristics of short observation interval, flexible operation environment and high data precision. Compared with the other air borne/space borne InSAR system, the GB-InSAR system has different image resolution, observation geometry and observation range. Thus, based on those features above, the interferometric phase of GB-InSAR has its own particularity. Mainly shows in the small offset between master and slave image, different decoherence sources, and the low-coherence area caused by varying viewing angle. This paper propose an interferometric phase processing method in order to recognize and compensate the low-coherence area based on their multi-characteristics, and rebuild the interferometric phase by using signal-domain estimation technology. This method will provide the satisfactory interferometric phase image for the following terrain map generation.
关键词： signal-domain phase reconstruction,recognize and compensate the low-coherence area,GB-InSAR,interferometric phase feature
更新于2025-09-23 15:22:29
-
High Resolution and Fast Processing of Spectral Reconstruction in Fourier Transform Imaging Spectroscopy
摘要： High-resolution spectrum estimation has continually attracted great attention in spectrum reconstruction based on Fourier transform imaging spectroscopy (FTIS). In this paper, a parallel solution for interference data processing using high-resolution spectrum estimation is proposed to reconstruct the spectrum in a fast high-resolution way. In batch processing, we use high-performance parallel-computing on the graphics processing unit (GPU) for higher efficiency and lower operation time. In addition, a parallel processing mechanism is designed for our parallel algorithm to obtain higher performance. At the same time, other solving algorithms for the modern spectrum estimation model are introduced for discussion and comparison. We compare traditional high-resolution solving algorithms running on the central processing unit (CPU) and the parallel algorithm on the GPU for processing the interferogram. The experimental results illustrate that runtime is reduced by about 70% using our parallel solution, and the GPU has a great advantage in processing large data and accelerating applications.
关键词： parallel computing,high performance,GPU,Fourier transform imaging spectrometer,spectrum reconstruction
更新于2025-09-23 15:22:29
-
3D surface reconstruction of retinal vascular structures
摘要： We propose in this paper, a three-dimensional surface reconstruction of a retinal vascular network from a pair of 2D retinal images. Our approach attempts to address the above challenges by incorporating an epipolar geometry estimation and adaptive surface modelling in a 3D reconstruction, using three steps: segmentation, 3D skeleton reconstruction and 3D surface modelling of vascular structures. The intrinsic calibration matrices are found via the solution of simplified Kruppa equations. A simple essential matrix based on a self-calibration method has been used for the ‘fundus camera-eye’ system. The used method has eventually produced vessel surfaces that could be fit for various applications, such as applications for computational fluid dynamics simulations and applications for real-time virtual interventional.
关键词： Kruppa equations,curvature-dependent subdivision,surface reconstruction,epipolar geometry,segmentation,retinal vascular network,self-calibration
更新于2025-09-23 15:22:29
-
Camera localization for augmented reality and indoor positioning: a vision-based 3D feature database approach
摘要： The recent fast development in computer vision and mobile sensor technology such as mobile LiDAR and RGB-D cameras is pushing the boundary of the technology to suit the need of real-life applications in the fields of Augmented Reality (AR), robotics, indoor GIS and self-driving. Camera localization is often a key and enabling technology among these applications. In this paper, we developed a novel camera localization workflow based on a highly accurate 3D prior map optimized by our RGB-D SLAM method in conjunction with a deep learning routine trained using consecutive video frames labeled with high precision camera pose. Furthermore, an AR registration method tightly coupled with a game engine is proposed, which incorporates the proposed localization algorithm and aligns the real Kinetic camera with a virtual camera of the game engine to facilitate AR application development in an integrated manner. The experimental results show that the localization accuracy can achieve an average error of 35 cm based on a fine-tuned prior 3D feature database at 3 cm accuracy compared against the ground-truth 3D LiDAR map. The influence of the localization accuracy on the visual effect of AR overlay is also demonstrated and the alignment of the real and virtual camera streamlines the implementation of AR fire emergency response demo in a Virtual Geographic Environment.
关键词： LiDAR,virtual geographic environment (VGE),localization,indoor positioning,camera pose,Augmented reality (AR),indoor GIS,3D reconstruction
更新于2025-09-23 15:22:29
-
[IEEE 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - Krakow (2018.10.16-2018.10.18)] 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - Design Techniques for Incremental Non-Regular Image Sampling Patterns
摘要： Even though image signals are typically acquired on a regular two dimensional grid, there exist many scenarios where non-regular sampling is possible. Non-regular sampling can remove aliasing. In terms of the non-regular sampling patterns, there is a high degree of freedom in how to actually arrange the sampling positions. In literature, random patterns show higher reconstruction quality compared to regular patterns due to reduced aliasing effects. On the downside, random patterns feature large void areas which is also disadvantageous. In the scope of this work, we present two techniques to design optimized non-regular image sampling patterns for arbitrary sampling densities. Both techniques create incremental sampling patterns, i.e., one pixel position is added in each step until the desired sampling density is reached. Our proposed patterns increase the reconstruction quality by more than +0.5 dB in PSNR for a broad density range. Visual comparisons are provided.
关键词： Non-Regular Sampling,Image Reconstruction
更新于2025-09-23 15:22:29
-
[IEEE 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - Krakow, Poland (2018.10.16-2018.10.18)] 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - Real-Time 3D Reconstruction in Minimally Invasive Surgery with Quasi-Dense Matching
摘要： In this work, a method for 3D reconstruction of Minimally Invasive Surgery data in real-time is presented. It is formulated on top of the already established framework of Quasi-Dense Matching, optimizing its components for speed. First, it recovers a set of sparse features, which are matched robustly. Then, 3D information is propagated in a spatial neighbourhood, until similarity reaches a prede?ned threshold, to cover a semi-dense portion of operating ?eld domain. Matching on dense level is achieved with Zero Mean Normalized Cross Correlation metric to establish correspondences. The algorithm is able to recover disparity maps with relatively small error, while maintaining real-time performance.
关键词： CUDA,MIS,Disparity Estimation,Stereo Matching,3D Reconstruction
更新于2025-09-23 15:22:29
-
[IEEE 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - Krakow (2018.10.16-2018.10.18)] 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - Influence of External and Internal Parameters on the Accuracy of a Mobile Tracking System Based on an IPhone
摘要： For the determination of a fitting rod during pedicle screw surgery, a measuring system consisting of an iPhone 7 and retroreflective markers was developed. In addition to intraoperative use, the system is also applied to track an ultrasound probe for preoperative determination of the Pelvic Tilt. For the intraoperative use of this system it is important to keep a distance of at least 1.5 m from the non-sterile iPhone 7 to the patient. Under operating conditions, the mobile tracking system has to cope with very bright lighting conditions, which makes it difficult to detect the retroreflective markers on the rigid bodies. The influence of the light condition and the distance of the markers to the camera are analyzed in an operating theatre with the possibility of controlling the operating lights to a defined light intensity. In addition to the external settings, the ISO and exposure time settings are changed internally in the mobile tracking system software. In this paper the influence of external and internal parameters on the accuracy of the tracking system is investigated.
关键词： 3D-reconstruction,mobile tracking
更新于2025-09-23 15:22:29
-
Improving the Signal-to-noise Ratio of Super Resolution Imaging Based on Single Pixel Camera
摘要： Based on the theories of single pixel camera and compressed sensing image reconstruction, the sparse basis, the projection method of measurement matrix and the signal reconstruction algorithm are optimized. Firstly, for the sparse representation of image, the restraint matrix is designed combining the characteristics of wavelet sparse coefficients to enhance the sparse representation ability of the discrete wavelet base, which improves the quality of image reconstruction and imaging by single pixel camera. Then in the single pixel camera system, the projection method is improved according to the characteristics of the DMD micro-mirror, and a new bilateral projection method based on the block diagonal measurement matrix is proposed to realize the super resolution imaging of the outdoor scene, reducing the number of measurement and improving the imaging quality. Finally, for the algorithm of image reconstruction, combining the characteristics of convex optimization and non-convex optimization algorithms, a new algorithm from convex optimization approximately to non convex optimization algorithm is proposed, and compared with traditional image reconstruction algorithm such as greedy pursuit algorithm, minimum norm algorithm and image interpolation, the peak signal to noise ratio (PSNR) and imaging quality of reconstructed images are effectively improved. The feasibility of the proposed methods is demonstrated by simulation experiments and imaging experiments of single pixel camera.
关键词： measurement matrix,Single pixel camera,sparse representation,super resolution,image reconstruction
更新于2025-09-23 15:22:29
-
An artificial retina processor for track reconstruction at the LHC crossing rate
摘要： The goal of the INFN-RETINA R&D project is to develop and implement a computational methodology that allows to reconstruct events with a large number (> 100) of charged-particle tracks in pixel and silicon strip detectors at 40 MHz, thus matching the requirements for processing LHC events at the full bunch-crossing frequency. Our approach relies on a parallel pattern-recognition algorithm, dubbed artificial retina, inspired by the early stages of image processing by the brain. In order to demonstrate that a track-processing system based on this algorithm is feasible, we built a sizable prototype of a tracking processor tuned to 3 000 patterns, based on already existing readout boards equipped with Altera Stratix III FPGAs. The detailed geometry and charged-particle activity of a large tracking detector currently in operation are used to assess its performances. We report on the test results with such a prototype.
关键词： track reconstruction,artificial retina,pattern recognition,LHC,FPGA
更新于2025-09-23 15:21:21
-
Pattern Reconstructability in Fully Parallel Thinning
摘要： It is a challenging topic to perform pattern reconstruction from a unit-width skeleton, which is obtained by a parallel thinning algorithm. The bias skeleton yielded by a fully-parallel thinning algorithm, which usually results from the so-called hidden deletable points, will result in the dif?culty of pattern reconstruction. In order to make a fully-parallel thinning algorithm pattern reconstructable, a newly-de?ned reconstructable skeletal pixel (RSP) including a thinning ?ag, iteration count, as well as reconstructable structure is proposed and applied for thinning iteration to obtain a skeleton table representing the resultant thin line. Based on the iteration count and reconstructable structure associated with each skeletal pixel in the skeleton table, the pattern can be reconstructed by means of the dilating and uniting operations. Embedding a conventional fully-parallel thinning algorithm into the proposed approach, the pattern may be over-reconstructed due to the in?uence of a biased skeleton. A simple process of removing hidden deletable points (RHDP) in the thinning iteration is thus presented to reduce the effect of the biased skeleton. Three well-known fully-parallel thinning algorithms are used for experiments. The performances investigated by the measurement of reconstructability (MR), the number of iterations (NI), as well as the measurement of skeleton deviation (MSD) con?rm the feasibility of the proposed pattern reconstruction approach with the assistance of the RHDP process.
关键词： skeleton,image processing,reconstructable skeletal pixel (RSP),thinning,hidden deletable point (HDP),pattern reconstruction
更新于2025-09-23 15:21:21