High resolution DEM generation from ALOS PRISM data - simulation and evaluation

The Advanced Land Observing Satellite (ALOS) has been developed to contribute to the fields of mapping, precise land coverage observation, disaster monitoring, and resource surveying. The Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM), carried on ALOS satellite is expected to generate worldwide Digital Maps in respects of its high resolution and stereoscopic observation. The development and evaluation of the software for generating Digital Elevation Model (DEM), based on this aim of ALOS operation, is now undertaking for the purpose of equipping the system which producing DEM semi-routinely in the Earth Observation Research and application Center (EORC). In this paper, the software´s outline of functions, the algorithm and the current status of its development and evaluation are described. PRISM consists of three panchromatic radiometers for forward, nadir, and backward views and acquires each image in the same orbit at almost the same time. It enables to generate more precision DEM frequently than usual stereoscopic observations. For this specific stereo image configuration, the triplet images matching algorithm is applied for the DEM generation. To evaluate the algorithm, Three Line Scanner (TLS) data is used as the PRISM simulation data and the Lider DEM is used as the reference data. The absolute accuracy of generated DEM is estimated in this simulation