DOI: 10.5281/zenodo.11453966
title: Spatiotemporal evolution of a controlled forest fire near Torre do Pinhão (Portugal)

description: This dataset represents part of the propagation of a controlled forest fire on March 1, 2019, near Torre do Pinhão, Portugal. The data was generated from a 15-minute video captured using a UAV. The video's description, frame selection and segmentation process are available at https://doi.org/10.5281/zenodo.7944963.The data represents the evolution of the burned region divided into 170 slices. Each slice is represented by a source polygon (S), a target polygon (T) and a one-to-one mapping of the vertices of S in T. Each polygon represents the burned region at a given time instant and each slice represents the evolution of the burned region during a time interval. These data are the inputs of interpolation methods to create a continuous representation of the fire spread, even when the original video frames are not good, for instance, due to occlusion of the area of interest by smoke. Figure goodCorrespondences.png shows an example of the correspondences between two polygons and the video presents the evolution of the burned region obtained using a simple linear interpolation method. The dataset was created using a supervised method. The source code and method description are available on gitHub.



source: the url of the original video (raw data) in zenodo.

eventData: the date and time of the prescribed forest fire.

location: the name of the place of the prescribed fire.

coordinates and coordinatesDMS: the coordinates of the prescribed fire in WSG84.  The later represents the coordinates in degrees, minutes and seconds.

numberOfFrames: the number of frames extracted from the video.

correspondences: this is a data structure to represent the correspondences between the polygons delimiting the extent of the burned area in frames (1, 2), (2, 3), … , (169, 170). The key is the number of the slice in [1, 170] and the value is a dictionary with the following keys:



frameNbInVideo_source: the number of the frame corresponding to the source polygon for the slice.

elapsedTimeInVideo_source: the elapsed time in milliseconds since the beginning of the video.

frameNbInVideo_target: the number of the frame corresponding to the source polygon for the slice.

numberOfVertices: the number of vertices of the source and target polygons.

vertexMappings versus sourceCoords and targetCoords: The correspondences between the source and target vertices in each slice are represented in two distinct but equivalent formats. In data_fmtA, the list sourceCoords holds the coordinates (x,y) of the source vertices and the list targetCoords holds the coordinates of the target vertices. The two lists have the same length and the correspondence is given by the position in the list. In data_fmtB, the correspondences are represented in the list vertexMapings where each entry holds the coordinates of the source and corresponding target vertices.




Note that the target polygon in slice i and the source polygon in slice i+1 are geometrically identical but they are topologically distinct because the number of vertices differs. This is to ensure that there is a one-to-one correspondence between the vertices of the source and target polygons in each slice. It is up to the vertex correspondence algorithm to add vertices to the source and target polygons to obtain a one-to-one correspondence between those polygons, as described on github. Click here to display a figure with an example of correspondences between the vertices of a source and a target polygons representing the extent of the burned area at two times.