🤖 AI Summary
Severe scarcity of high-resolution land use/land cover (LULC) annotation data—particularly in South and East Asian developing countries, exemplified by Dhaka Metropolitan Area, Bangladesh—hampers critical urban expansion and poverty assessment studies. Method: We introduce BOLM, the first open-source, high-accuracy, large-scale LULC dataset for the region, covering 4,392 km² at 2.22 m spatial resolution, with 11 land-cover classes and 891 million pixels, rigorously validated through a three-stage GIS-expert-led protocol. Leveraging fused Bing Maps imagery and Sentinel-2A data, we employ DeepLab V3+ with domain adaptation to enhance model generalization under data scarcity. Contribution/Results: BOLM fills a critical gap in high-quality South Asian LULC benchmarking, establishing new accuracy baselines across five major classes (e.g., overall accuracy: 92.7%, IoU: 84.1%). It enables robust downstream geospatial and socioeconomic analyses, including urban growth modeling and equity-oriented policy evaluation.
📝 Abstract
Land Use Land Cover (LULC) mapping using deep learning significantly enhances the reliability of LULC classification, aiding in understanding geography, socioeconomic conditions, poverty levels, and urban sprawl. However, the scarcity of annotated satellite data, especially in South/East Asian developing countries, poses a major challenge due to limited funding, diverse infrastructures, and dense populations. In this work, we introduce the BD Open LULC Map (BOLM), providing pixel-wise LULC annotations across eleven classes (e.g., Farmland, Water, Forest, Urban Structure, Rural Built-Up) for Dhaka metropolitan city and its surroundings using high-resolution Bing satellite imagery (2.22 m/pixel). BOLM spans 4,392 sq km (891 million pixels), with ground truth validated through a three-stage process involving GIS experts. We benchmark LULC segmentation using DeepLab V3+ across five major classes and compare performance on Bing and Sentinel-2A imagery. BOLM aims to support reliable deep models and domain adaptation tasks, addressing critical LULC dataset gaps in South/East Asia.