Mosaic crack
![mosaic crack mosaic crack](https://mymodernmet.com/wp/wp-content/uploads/2021/05/ememem-street-mosaic-art-1-1153x1536.jpg)
Each hypothesis is defined by a planar convex quadrilateral in the image. First, we extract hypotheses of building facades based on a robust line fitting algorithm. In this paper, we integrate both the appearance and geometric properties of an image to find unique matches. are also unstable under large viewing angle variations. Feature descriptors such as SIFT that are based on region patches. Such images comprise repetitive and symmetric patterns, which render popular algorithms e.g. This paper presents a novel approach to finding point correspondences between images of building facades with wide viewpoint variations, and at the same time returning a large list of true matches between the images. Experimental results show that the algorithm complexity is greatly reduced and improves detection integrity for surface cable defects using our improved SIFT to automaticslly stitch the defect images together. Finally, image fusion is implemented and a complete image of a defect is obtained. The simplified SIFT operator is employed to describe the feature points and match the images. Second, according to defect images collected by the system, the steps of the SIFT operator such as the distribution of the main direction for the matching feature points and the matching image rotation is simplified.
![mosaic crack mosaic crack](https://knovhov.com/wp-content/uploads/2021/05/1-1-1-rotated.jpg)
First, feature points are extracted by a Harris operator. An improved scale invariant feature transform (SIFT) feature matching algorithm for image mosaicing is proposed to real time processing to obtain a whole defect effectively.
![mosaic crack mosaic crack](https://i.pinimg.com/736x/39/c7/5b/39c75b88a7202b5f21280f552ffd2a52.jpg)
![mosaic crack mosaic crack](https://www.hominter.com/image/catalog/mosaic-tiles/bee164ee69.jpg)
Surface defection may be distributed in several images. It uses four cameras to acquire images around the cable surface. In order to realize automatic nondestructive testing for surface cable damage on a cable-stayed bridge, a distributed machine vision system was developed. © 2018, Editorial Office of Semiconductor Optoelectronics. Experimental results show that the proposed method not only improves the accuracy of image matching, but also on the premise of the same data processing, it decreases the process time to be less than 60% of that of the RANSAC algorithm, which improves the efficiency of the algorithm. This can greatly reduce the number of iterations of the algorithm and improve the operation efficiency and accuracy of the algorithm. In this paper, based on the SIFT algorithm to complete the initial feature matching, the RANSAC algorithm is improved by reasonably reducing the number of elements in a sample set, which can increase the proportion of intra-office points in the sample, and rapidly rejecting unreasonable initial parameter models by using pre-test. For the traditional RANSAC algorithm, it presents such problems as lots of iterations, low operation efficiency and low precision of the homography matrices estimation. In order to improve the speed and accuracy of multi-spectral image matching, an improved random sampling consistency (RANSAC) algorithm is proposed. The comparison of instance results shows that the correct matching rate of feature points is as high as 97.1%, and the mosaic efficiency is improved by more than 35.2% compared with the conventional SIFT image mosaic algorithm. The proposed algorithm of large-area image mosaic is verified by the experiment processing and performance analysis, which can reduce the search of non-essential feature and achieve the seamless splicing with reliable precision. It is used to achieve a splicing panoramic image of the complete bridge crack with wide viewing angle and high resolution. Then these sequential images are respectively mapped into the same reference plane by projection transformation, and gradually blended by improved weighted fusion algorithm. The feature points of the overlapped regions are extracted by the SIFT algorithm based on adaptive contrast threshold, and the image registration is completed by the improved RANSAC algorithm. The algorithm combines the phase correlation method to estimate the overlapped regions of adjacent images. In order to meet the requirements of actual engineering inspection, this paper studies and improves the large-area mosaic algorithm for multiple images of bridge crack. The surface cracks of bridge building will seriously effect its service life.