Invalid-point removal based on epipolar constraint in the structured-light method

Qi, Zhaoshuai; Wang, Zhao; Xing, Chao; Gao, Jianmin

doi:10.1016/j.optlaseng.2018.01.018

Cited by 19 publications

(5 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After acquiring the images, the intrinsic, extrinsic, and distortion parameters of the cameras are obtained based on the calibration method proposed by Zhang. 51 To reduce the complexity of matching problem, the epipolar constraint 52 provides an efficient strategy that corresponding points only have horizontal offsets. Once the image pairs have been rectified, the points P l and P r satisfy that u r = u l − d , v r = v l , where d is the disparity value between the two points.…”

Section: Methodsmentioning

confidence: 99%

State measurement of isolating switch using cost fusion and smoothness prior based stereo matching

Luo

et al. 2020

International Journal of Advanced Robotic Systems

View full text Add to dashboard Cite

To better monitor the state of isolating switches, an efficient binocular vision-based state measurement system is proposed in this article. Two optimal cameras are selected as the vision of our inspection system. Firstly, stereo calibration and distortion rectification are performed on acquired image pair. Secondly, to recover the three-dimensional information of switch, we propose a semi-global stereo matching method by using data- and structure-driven cost volume fusion and then optimizing raw disparity map with weighted- and edge discriminated-smoothness prior. Gradient content is enforced on the weight for suppressing small-weight-accumulation problem in weak-textured regions. Besides, Hough transform with feature constraints is implemented for removing the chaotic lines and extracting center line of the switch arm. Finally, based on the center line and corresponding disparity map of the switch arm, triangulation principle is used for calculating the true angle between the switch arm and insulator such that whether or not the isolating switch is fully closed can be detected. The experimental results demonstrate that the proposed stereo matching method can achieve good performance in Middlebury v.3 data set and switch images, and the system can precisely measure the state of switches.

show abstract

Section: Methodsmentioning

confidence: 99%

State measurement of isolating switch using cost fusion and smoothness prior based stereo matching

Luo

et al. 2020

International Journal of Advanced Robotic Systems

View full text Add to dashboard Cite

show abstract

“…In order to solve the problem of insufficient global learning ability of the model, Yan et al and Luo et al [20,21] proposed to use deep learning algorithms to recover the real phase map. Zhao et al [9] removed the points where the projector image coordinates did not meet the epipolar constraint. However, these methods are not suitable for all scenarios because they depend on the scene and computing power.…”

Section: Related Workmentioning

confidence: 99%

“…Zhao et al. [9] removed the points where the projector image coordinates did not meet the epipolar constraint. However, these methods are not suitable for all scenarios because they depend on the scene and computing power.…”

Section: Related Workmentioning

confidence: 99%

“…To solve the problem of invalid points caused by phase unwrapping described above, researchers have proposed a number of ways to identify and remove invalid points. Some methods introduce additional auxiliary hardware to eliminate errors [9], which increases the complexity of the system. The more mainstream approaches are to use phase neighbourhood processing and assume similar differences within the neighbourhood of phase points [8,[10][11][12][13][14][15].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A Markov random field based method for removing invalid unwrapping phase points in 3D reconstruction

Gao

Cheng

et al. 2023

IET Image Processing

View full text Add to dashboard Cite

Fringe projection profilometry is widely used in 3D structured light due to its fast speed and accuracy. However, in the process of phase unwrapping, it is easy to cause invalid points in the edges and shadows of objects, which leads to error points in 3D reconstruction. To solve this problem, we propose an invalid points removal method based on Markov random fields. Specifically, the proposed method formulates unwrapped phase and mask maps as energy functions and uses iterative methods to minimize them. Furthermore, we validate the proposed method in a monocular structured light system and compare it with existing algorithms. Results show that the proposed method effectively identifies edges and shadows while preserving valid points, and has strong robustness and correctness.

show abstract

“…There are polar geometric constraints for the same point in different images (Qi Z. et al, 2018). Antipolar geometry is the internal projective geometry between two views, independent of landscape structure and dependent only on the internal and external parameters of the camera.…”

Section: Basic Matrix Estimationmentioning

confidence: 99%

Study on Phenotypic Characteristics of Millet Based on 3d Model

Sun

Wang

et al. 2023

INMATEH

View full text Add to dashboard Cite

As one of the ancient cultivated crops in China, millet has the characteristics of high nutritional value, drought resistance and barrenness. It also plays an important role in ensuring the supply of food in our country. At present, most of the millet breeding work uses manual extraction of phenotypic information, which is laborintensive and inefficient. Therefore, the development of an automated, efficient and accurate millet phenotype detection method has practical significance for the extraction of the millet genome. In this study, a combination of sparse reconstruction based on Structure from Motion (SfM) and Patch-based Multi-View Stereo (PMVS) was used to select three different varieties of millet. A total of 81 samples of 9 samples in each period were reconstructed to obtain a 3D model of millet. The combination of conditional filtering and statistical filtering is used to remove the noise points generated during the photographing process, and finally the obtained point cloud data is used to measure the agronomic traits of millet such as plant height and leaf area. The results show that the interval angle of 5° is the best reconstruction angle of millet. The coefficient of determination R2 of point cloud measurement results and manual measurement data regression analysis is higher than 0.94, indicating that the method used for 3D reconstruction has high applicability to different millet in different periods and high-throughput measurement of millet by the method in this paper is feasible. This study provides a theoretical basis for a millet phenotypic information measurement device

show abstract

Invalid-point removal based on epipolar constraint in the structured-light method

Cited by 19 publications

References 13 publications

State measurement of isolating switch using cost fusion and smoothness prior based stereo matching

State measurement of isolating switch using cost fusion and smoothness prior based stereo matching

A Markov random field based method for removing invalid unwrapping phase points in 3D reconstruction

Study on Phenotypic Characteristics of Millet Based on 3d Model

Contact Info

Product

Resources

About