Digital elevation model combination using triangular image warping interpolation and maximum likelihood

The main purpose of this letter was to construct a large-region Digital Elevation Model (DEM) from small-area DEMs. Image mosaicking and data fusion techniques are necessary in constructing a large-region DEM from small-area DEMs. The topographic distortion of the image must be corrected because of viewing angle and time differences among the acquired images. The orthorectification and image mosaicking are executed using a grid matrix of the longitude and latitude obtained from DEM extraction at 10 m intervals. The height at each grid location in the overlapping region is determined using a triangular image warping interpolation and a maximum likelihood procedure. The images used in the experiments are two pairs of images from the SPOT High Resolution Visible (HRV) sensor. The results show that a large-region DEM can be obtained from small-area DEMs.