52 results about "Stereo reconstruction" patented technology

The invention relates to a multi-view stereo reconstruction method based on an Internet photo gallery which utilizes a plurality of photos of the same scene at different viewing angles obtained from the Internet so as to restore the sparse three-dimensional point cloud of the scene for obtaining camera parameter, and then densify the sparse three-dimensional point cloud for restoring the dense three-dimensional point cloud of the scene. The method provided by the invention comprises the following specific steps that the geometry and movement at the scene are stored at the same time, that is, the camera is demarcated and the sparse three-dimensional point cloud of the scene is restored; image screening is performed, a nearest image collection is selected for each photo, and an optimal image sub collection is selected for each three-dimensional point; the three-dimensional points are densified so as to count out new three-dimensional points, and an area generation method of taking the conventional three-dimensional points as a center and generating towards the near area is adopted; and the larger-error three-dimensional points are filtered and got rid of. The invention provides a photo screening method, avoids redundant calculation, upgrades the speed of model generation, filters and gets rid of inaccurate three-dimensional points, and improves the accuracy of the model generation.

In an embodiment, a method determines a three-dimensional model from a plurality of images taken of a geographic region by one or more cameras from different perspectives. The method includes determining, using a first stereo reconstruction technique: (i) a plurality of three-dimensional candidate surface points from the plurality of images, and (ii) which of the images in the plurality of images view each of the plurality of candidate surface points. The method also includes identifying an empty space between each of the plurality of candidate surface points and each camera model for the respective images determined to view the candidate surface point. The method further includes for each of a plurality of pairs of images from the plurality of images, determining, using a second stereo reconstruction technique, a surface estimate for the pair of images. The method also includes merging the surface estimates to identify a final surface.

The invention discloses a semantic stereo reconstruction method for a remote sensing image, and mainly solves the problem of low semantic three-dimensional reconstruction precision caused by ignoringrelated information of semantic segmentation and parallax estimation in the prior art. According to the implementation scheme, firstly, experimental data are preprocessed; a semantic segmentation network and a parallax estimation network are trained by using the training data; the trained network is tested on the test image, and test results of different frequency band information are fused to obtain a fused semantic segmentation result and a fused parallax result; the error correction module is used for assisting each other to correct the error part of the opposite side; and the disparity information is calculated to obtain height information, and the semantic segmentation result is combined with the height information to obtain a semantic three-dimensional reconstruction result of the image. According to the method, the proportion of small samples is improved, the influence of data on the network is balanced, the semantic information and the parallax result are fused with each other,the accuracy of semantic three-dimensional reconstruction of the remote sensing image is improved, and the method can be used for urban scene three-dimensional reconstruction.

A method is disclosed for the analysis of scenarios where there are dynamically occurring objects capable of occluding each others. Application of the method in vision systems is also disclosed. Methods for incorporating visibility constraints for occluding scenarios are provided in a multi-camera setting. Other static constraints such as image resolution and field-of-view, and algorithmic requirements such as stereo reconstruction, face detection and background appearance are also addressed. A generic framework for sensor planning is also provided.

Stereo image reconstruction techniques are described. An image from a root viewpoint is translated to an image from another viewpoint. Homography fitting is used to translate the image between viewpoints. Inverse compositional image alignment is used to determine a homography matrix and determine a pixel in the translated image.

The invention provides an underwater binocular stereo vision measuring system and method based on a dynamic reference coordinate system. A dynamic reference coordinate system is built through using four active cursor targets to eliminate a measurement error caused by vibration. An underwater stereo vision reconstruction method based on a light field model is used to calculate a three-dimensional coordinate of a target angular point under a scanning system. A coded point coordinate system is established by carrying out singular value decomposition on a coordinate matrix of the target angular point. A spatial three-dimensional point of a laser stripe in a scanning system coordinate system is calculated by using an underwater laser stripe matching and stereo reconstruction method based on the light field model. The measurement error caused by the vibration is eliminated by calculating the three-dimensional coordinate of a laser stripe center point of each group of pictures under the scanning system and converting to the scanning system coordinate system of the first group of picture target points. An underwater target point is packaged in a high pressure resistant state and can withstand high pressure of deep sea 4000 meters. Therefore, the system can be used for a dynamic high precision measurement scene of the deep sea 4000 meters.

Disclosed are a system and method for efficient 3d reconstruction of objects with telecentric line-scan cameras. In this invention, systems and methods are described that allow performing stereo reconstruction with line-scan cameras in general configurations. Consequently, the cumbersome exact alignment of the sensor lines becomes superfluous. The proposed method requires that telecentric lenses instead of perspective lenses are mounted on the line-scan cameras. In this case, the images can be accurately rectified with stereo rectification. The rectified images can be used to perform an efficient stereo matching. The method comprises a camera model and a calibration procedure that allow to precisely model the imaging process, also including the modelling of lens distortions even if the sensor lines are not exactly mounted behind the principal points. This ensures a high accuracy of the resulting 3D reconstruction.

The invention discloses an auxiliary robot for total knee joint replacement surgery. Two groups of stereo vision and light source mechanical arms with seven joints are designed, and the function of rapid and accurate stereo reconstruction of knee joint surgery is achieved; two mechanical arms with supporting and clamping positioning components are designed, the fixation of thighs and cruses in thetotal knee joint replacement surgery is achieved, and thus knee joints are fixed, and guarantee is provided for the accuracy of the surgery; two mechanical arms for turnover clamping of skin and muscle tissues are designed, and four novel turnover clamping components work together to realize minimally invasive and accurate turnover of skin and muscle tissues of a knee joint incision and reduce secondary trauma of the surgery incision turnover; an surgery mechanical arm with four executive components is designed, the knee joint skin and muscle tissue cutting, incision hemostasis, leg bone cutting, leg bone drilling and other functions for the knee joint replacement surgery are achieved, real-time function switching is achieved, and the accuracy, stability and efficiency of the surgery canbe greatly improved.

Stereo image reconstruction techniques are described. An image from a root viewpoint is translated to an image from another viewpoint. Homography fitting is used to translate the image between viewpoints. Inverse compositional image alignment is used to determine a homography matrix and determine a pixel in the translated image.

In an embodiment, a method determines a three-dimensional model from a plurality of images taken of a geographic region by one or more cameras from different perspectives. The method includes determining, using a first stereo reconstruction technique: (i) a plurality of three-dimensional candidate surface points from the plurality of images, and (ii) which of the images in the plurality of images view each of the plurality of candidate surface points. The method also includes identifying an empty space between each of the plurality of candidate surface points and each camera model for the respective images determined to view the candidate surface point. The method further includes for each of a plurality of pairs of images from the plurality of images, determining, using a second stereo reconstruction technique, a surface estimate for the pair of images. The method also includes merging the surface estimates to identify a final surface.

A hybrid 3D optical scanning system combining methodologies of active stereo 3D reconstruction and deflectometry to provide accurate 3D surface measurements of an object under inspection. In a preferred embodiment, the present system comprises a calibrated digital camera stereo pair and first digital projector for active stereo 3D reconstruction metrology positioned at selected distance apart on the same horizontal plane facing the inspection object at an optimal incidence angle relative to the object surface. A secondary digital projector for deflectometry is directed to project a pattern sequence across the optical projection path of the first digital projector and onto a nonplanar deflection screen extended between the digital camera and the inspection object at a selected angle relative thereto, the selected angle being chosen so that that the pattern projected onto the deflection screen by the secondary digital projector reflects from the surface of the inspection object towards the digital camera. Calibrated active stereo 3D reconstruction is used to derive global shape and the uncalibrated nonplanar deflected light acquires curvature of local fine deformations and surface imperfections along the object surface. The calibrated camera allows per pixel correlations to be defined between the separate acquisition methods and produces accurate absolute measurements of both shape and local features of specular, glossy, metallic curved surfaces.