Validation of aircraft height extraction from Worldview-1 stereo data

The satellite Worldview-1 was launched in September 2007; the optical sensor is acquiring panchromatic data of 0.5 m geometric resolution at nadir. A stereo data set covering an urban area was provided by DigitalGlobe to evaluate the potential of object height extraction and digital surface model (DSM) generation. Because of a lack of reference elevation data, an accuracy assessment of eight aircraft at Ontario airport was undertaken. The object heights were compared with the known height of every aircraft type. They were well estimated with a mean absolute error (MAE) for all measured positions between 0.59 and 0.62 m. One aircraft was analysed in more detail and its shape evaluated qualitatively. The results are promising and show that the sensor is suitable for DSM generation and object height extraction. It has the potential for improved three-dimensional (3D) information extraction and thus can contribute to more accurate, detailed and realistic 3D models. Future studies will provide more information about the absolute height accuracies to be expected for different surfaces of the Earth.