Nanjing University

Nanjing University 5d Technology Co., Ltd.

Xun Cao

Xiang Li

Feng Yan

Xi Zhu

Weisong Pan

Wei Li

Jun Wang

Chen Chen

Yuanyuan Li

Xia Hua

Jianwen Ding

Jibin Wang

Dapeng Li

Wenzhu Wang

Xiaowen Li

Linsen Chen

Yan Zhang

Yanru Wang

Hao Zhu

Weibin Sun

Zhuoyi Liao

Yidi Zhang

Du Chen

Erqi Huang

Zhihao Huang

Ye Huang

Zhengyu Liu

Chen Wang

Lijing Cai

A three-dimensional (3D) reconstruction device and a method of flame spectra are provided. The device has a plurality of prism-mask shooting systems and a plurality of mirrors. The prism-type shooting systems are set up around a combustion area to be reconstructed and each is provided with two mirrors which are tilted on the left and right of an axis of the shooting system, so that data of a flame are reflected by the mirrors into the prism-mask shooting systems, thus realizing the real-time acquisition of hyperspectral data of the flame from multiple shooting angles. The reconstruction method includes following steps of acquiring, by a calibration cylinder, an area to be reconstructed, synchronously acquiring and preprocessing hyperspectral data of a flame, and finally reconstructing 3D spectral data of the flame by a 3D reconstruction algorithm of flame spectra.

Three-dimensional (3D) reconstruction device and method of flame spectra

A ray-free dental X-ray periapical film virtual imaging method based on virtual reality (VR) includes: constructing a VR positioning system, and tracing a position of a tracker bonded bound with a tube of a dental film machine and a spatial attitude matrix in real time; scanning and reconstructing a digital three-dimensional (3D) model of dentition; respectively setting different materials and transparency for a shell of a tooth model and an internal pulp cavity; constructing a virtual environment of a simulated oral cavity; assigning an attitude and position of the tracker to a virtual camera by using a network communication module, and controlling the virtual camera to move; placing the tracker in a specific position and orientation to calibrate so as to obtain a position coordinate of a dentition model in the virtual environment; and aligning the tube to teeth, and rendering a virtual periapical film.

Ray-free dental x-ray periapical film virtual imaging method based on virtual reality

A snapshot hyperspectral imaging method includes the steps of: S, selecting a set of reference wavelengths for calibration, rectifying the shifted positions due to dispersion at each reference wavelength, and selecting a center wavelength; S, estimating relative dispersion at each reconstructed wavelength with respect to the center wavelength; S, generating a dispersion matrix describing the direction of dispersion, and generating a spectral response matrix using a spectral response curve of a sensor; S, capturing images blurred with dispersion; S, deblurring the dispersed images captured in Susing the dispersion matrix and the spectral response matrix generated in Sto obtain spectral data spatially aligned in all spectrums; and S, projecting the aligned spectral data obtained in Sinto color space, extracting a foreground image by a threshold method, sampling the dispersed images obtained in Sas strong prior constraints for the foreground image, and reconstructing accurate spatial hyperspectral data.

Snapshot hyperspectral imaging method with de-blurring dispersed images

A Free Viewpoint Video (FVV) generation and interaction method based on a deep Convolutional Neural Network (CNN) includes the steps of: acquiring multi-viewpoint data of a target scene by a synchronous shooting system with a multi-camera array arranged accordingly to obtain groups of synchronous video frame sequences from a plurality of viewpoints, and rectifying baselines of the sequences at pixel level in batches; extracting, by encoding and decoding network structures, features of each group of viewpoint images input into a designed and trained deep CNN model, to obtain deep feature information of the scene, and combining the information with the input images to generate a virtual viewpoint image between each group of adjacent physical viewpoints at every moment; and synthesizing all viewpoints into frames of the FVV based on time and spatial position of viewpoints by stitching matrices. The method does not require camera rectification and depth image calculation.

Free viewpoint video generation and interaction method based on deep convolutional neural network

A method for removing periodic noise from a reconstructed light field image includes the steps of: acquiring a light field image of a sample; acquiring an optical center position map without the sample; calibrating the imaging centers of the microlenses and performing reconstruction on the light field image; transforming a reconstructed light field image to the frequency domain and generating an image frequency spectrum; preprocessing the image frequency spectrum; generating a low-pass filter; multiplying the low-pass filter with the preprocessed image frequency spectrum, and then setting the frequency spectrum value of the low-frequency component to zero; performing binarization on the reconstructed light field image frequency spectrum to obtain an image mask; removing the high-frequency periodic noise component from the original frequency spectrum of the reconstructed light field image; and transforming the filtered reconstructed light field image frequency spectrum back to the spatial domain to obtain the reconstructed light field image.

Frequency domain-based method for removing periodic noise from reconstructed light field image

A method for accelerating hyperspectral video reconstruction includes steps of: acquiring, according to a spectral video and an RGB video captured by a hyperspectral video camera, a calibration matrix of the spectral video and the RGB video; sorting the calibration matrix to generate an ordered calibration matrix; converting, according to the ordered calibration matrix, the spectral video and the RGB video into a data matrix in a parallel manner; acquiring all related calibration points of a reconstruction region according to the ordered calibration matrix; and, reconstructing a hyperspectral video in a parallel manner according to the related calibration points and the data matrix. The related calibration points are acquired by sorting the calibration matrix, such that the number of times the calibration matrix is traverse is reduced, and the computation amount of hyperspectral video reconstruction is decreased.

Method and apparatus for accelerating hyperspectral video reconstruction

The present invention provides an auxiliary berthing method and system for a vessel. Position information of a vessel relative to a berth is determined by a solar blind ultraviolet imaging method; meanwhile, by a GPS method, an attitude angle of the vessel relative to the berth is determined by at least two GPS receivers. Thus, the vessel can be berthed safely when getting close to the shore at low visibility. Further, in the method and device of the present invention, it can be preferable to integrate coordinate data and angle data received by a solar blind ultraviolet imaging module and GPS signal receiving modules by a normalized correlation algorithm and a data fusion algorithm, so as to improve the positioning accuracy.

Auxiliary berthing method and system for vessel

The present invention provides an auxiliary berthing method and system for a vessel. In the berthing method, by a solar blind ultraviolet imaging method, a position and an attitude of a vessel relative to a shoreline of a port berth during berthing are calculated by at least two solar blind ultraviolet imaging modules according to light signals received by a solar blind ultraviolet light source array arranged in advance on the shore. Further, when more than three solar blind ultraviolet imaging modules are used, in the method and device of the present invention, a normalized correlation algorithm and a data fusion algorithm are used to improve the accuracy of the position and attitude data of the vessel.

A path detection system based on SBUV light signals is provided, including a SBUV light signal emitter, a SBUV detectors and a signal processing module, wherein the SBUV light signal emitter is arranged on a road to serve as a path mark line; the SBUV detector is configured to detect the path mark line and transmit the detected signals from the SBUV light signal emitter to the signal processing module; and the signal processing module acquires a traveling path in real time by using a path line extraction algorithm, and eventually outputs path information.

Path detection system based on solar blind ultraviolet light signals

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Jiangsu, China

Xun Cao