Topic
World file
About: World file is a research topic. Over the lifetime, 3 publications have been published within this topic receiving 54 citations.
Papers
TL;DR: The algorithm proposed in this paper satisfies the time and accuracy requirements of postearthquake response, which has an important application value.
Abstract: The image collection system based on the unmanned aerial vehicle plays an important role in the postearthquake response and disaster investigation. In the postearthquake response period, for hundreds of image stitching or 3D model reconstruction, the traditional UAV image processing methods may take one or several hours, which need to be improved on the efficiency. To solve this problem, the UAV image rapid georeference method for postearthquake is proposed in this paper. Firstly, we discuss the rapid georeference model of UAV images and then adopt the world file designed and developed by ESRI to organize the georeferenced image data. Next, the direct georeference method based on the position and attitude data collected by the autopilot system is employed to compute the upper-left corner coordinates of the georeferenced images. For the differences of image rotation manners between the rapid georeference model and the world file, the rapid georeference error compensation model from the image rotation is considered in this paper. Finally, feature extraction and feature matching for UAV images and referenced image are used to improve the accuracy of the position parameters in the world file, which will reduce the systematic error of the georeferenced images. We use the UAV images collected from Danling County and Beichuan County, Sichuan Province, to implement the rapid georeference experiments employing different types of UAV. All the images are georeferenced within three minutes. The results show that the algorithm proposed in this paper satisfies the time and accuracy requirements of postearthquake response, which has an important application value.
9 citations
30 Apr 2018-ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences
TL;DR: A near-real-time rapid georeference method for UAV remote sensing disaster data that meets the demand of rapid disaster response, which is of great value in disaster emergency application is proposed.
Abstract: . The rapid collection of Unmanned Aerial Vehicle (UAV) remote sensing images plays an important role in the fast submitting disaster information and the monitored serious damaged objects after the earthquake. However, for hundreds of UAV images collected in one flight sortie, the traditional data processing methods are image stitching and three-dimensional reconstruction, which take one to several hours, and affect the speed of disaster response. If the manual searching method is employed, we will spend much more time to select the images and the find images do not have spatial reference. Therefore, a near-real-time rapid georeference method for UAV remote sensing disaster data is proposed in this paper. The UAV images are achieved georeference combined with the position and attitude data collected by UAV flight control system, and the georeferenced data is organized by means of world file which is developed by ESRI. The C # language is adopted to compile the UAV images rapid georeference software, combined with Geospatial Data Abstraction Library (GDAL). The result shows that it can realize rapid georeference of remote sensing disaster images for up to one thousand UAV images within one minute, and meets the demand of rapid disaster response, which is of great value in disaster emergency application.
4 Oct 2015
TL;DR: A mathematically rigorous model of file system behaviour, SibylFS, is given that specifies the range of allowed behaviours of a file system for any sequence of the system calls within its scope, and that can be used as a test oracle to decide whether an observed trace is allowed by the model, both for validating the model and for testing file systems against it.
Abstract: Systems depend critically on the behaviour of file systems, but that behaviour differs in many details, both between implementations and between each implementation and the POSIX (and other) prose specifications. Building robust and portable software requires understanding these details and differences, but there is currently no good way to systematically describe, investigate, or test file system behaviour across this complex multi-platform interface.In this paper we show how to characterise the envelope of allowed behaviour of file systems in a form that enables practical and highly discriminating testing. We give a mathematically rigorous model of file system behaviour, SibylFS, that specifies the range of allowed behaviours of a file system for any sequence of the system calls within our scope, and that can be used as a test oracle to decide whether an observed trace is allowed by the model, both for validating the model and for testing file systems against it. SibylFS is modular enough to not only describe POSIX, but also specific Linux, OS X and FreeBSD behaviours. We complement the model with an extensive test suite of over 21 000 tests; this can be run on a target file system and checked in less than 5 minutes, making it usable in practice. Finally, we report experimental results for around 40 configurations of many file systems, identifying many differences and some serious flaws.
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2018 | 2 |
| 2015 | 1 |