Contribution of nDSM derived from VHR stereo imagery to urban land-cover mapping in Sub-Saharan Africa

Mapping the urban land cover from VHR optical imagery remains a challenging task, more particularly in cities that present complex landscapes and patterns. In this study, we assessed the contribution of height data derived from WorldView-3 stereo imagery for mapping the land cover of Sub-Saharan African cities. Our case study is located in Ouagadougou, Burkina Faso. An OBIA approach was implemented using an open-source semi-automated processing chain. The use of the nDSM as input to the segmentation and/or to the classification in addition to the four VNIR WorldView-3 optical bands was evaluated. The quantitative and qualitative analysis of the results indicate an improvement for a number of classes, among which the class `Buildings' that is of particular interest in many applications. Visually, this improvement is more noticeable in planned settlements and industrial areas than in unplanned settlements.