A dataset of 1600 images extracted from 5 cm RGB orthophotos for the classification of 12 classes of roofing materials

This dataset contains a collection of 1601 image tiles of 64x64 pixels (3.2x3.2m²) annotated for 12 roofing materials. These tiles were extracted from 5 cm RGB orthophotos acquired by the city of Namur (Belgium) in 2017. The additional data used to create this dataset are (a) a Namur roof section mask, and (b) a set of 1601 material samples acquired using stratified random sampling. The tiles were obtained as follows: the centroid of each roof section containing a sample is used to extract tiles. A size of 64x64 pixels has been chosen so that a tile contains information for only one roof section, in order to learn only the colour and texture of the roof materials. This also avoids adding information outside the given roof section. The tiles are thus extracted for each orthophoto spectral band and labelled with the identifier of the class of roofing materials to which they belong. Here are the 12 material classes considered, preceded by their labels: 0- Solar panels1- Brown tiles2- Orange tiles3- Black tiles4- Dark membranes5- White membranes6- Slates containing asbestos7- Slates without asbestos8- Corrugated asbestos-cement sheets9- Gravel10- Vegetation12- Metals There are approximately 140 tiles by material class except for the vegetated roof sections (class 10) which contains only 47 samples due to its rarety. The dataset contains 1 folder for each spectral band. Each folder contains 1601 thumbnails in tif format named as follows: img[tile id]_[class label].tif It is suggested to apply pre-processing to these images as done by Wyard et al. (2023).本数据集包含1601张64×64像素（对应实地面积3.2×3.2平方米）的图像切片，针对12种屋面材料完成标注。这些切片提取自比利时那慕尔（Namur）市2017年获取的5厘米分辨率RGB正射影像（orthophoto）。 构建该数据集所用的额外数据包括：(a) 那慕尔市屋面区域掩码；(b) 采用分层随机抽样（stratified random sampling）获取的1601份材料样本集。 图像切片的提取流程如下：以每个包含样本的屋面区域的质心为基准提取切片。选择64×64像素的尺寸，是为了确保每张切片仅包含单个屋面区域的信息，仅学习屋面材料的颜色与纹理特征，同时避免引入给定屋面区域之外的无关信息。针对正射影像的每个光谱波段（spectral band），均提取对应切片，并为其标注所属屋面材料类别的标识符。 本次考量的12种材料类别及其标签如下： 0- 太阳能光伏板；1- 棕色陶瓦；2- 橙色陶瓦；3- 黑色瓦片；4- 深色防水卷材；5- 白色防水卷材；6- 含石棉板岩瓦；7- 不含石棉板岩瓦；8- 波纹石棉水泥板；9- 砾石屋面；10- 植被屋面；12- 金属屋面 各类别切片数量约为140张，仅植被屋面类别（类别10）因较为罕见，仅包含47份样本。 本数据集按光谱波段分为多个文件夹，每个文件夹包含1601张TIFF格式图像，命名规则为：img[切片ID]_[类别标签].tif。 建议参考Wyard等人（2023）的研究，对这些图像进行预处理。