A digital elevation model (DEM) can be generated using a gradient of a single image and a stereo image pair from an imaging sensor or laser altimeter sensor on an orbiter. These DEMs are affected by intrinsic problems such as stereo noise in the triangulation process or low spatial resolution from sparse measurement points. Various image-based techniques are presently used to enhance the resolution of DEMs, but they can be very challenging since calculating each surface point direction vector from one or more partially overlapped images requires many assumptions. In this paper, an approach is proposed to enhance the resolution of a coarse DEM, using the information of a surface normal extracted from an ortho-rectified planetary image dataset. The surface normal extracted from the ortho-rectified planetary image dataset and coarse DEM are well-aligned, and the surface normal also offers direction vectors of uniform quality at every surface point.The keypoint of this improvement is the separation of the surface normal as a map, to overcome the ambiguity in the role of surface direction information. The coarse DEM is then optimized using the high-resolution surface normal information, so that it displays the characteristics of the terrain in the surface normal map. For performance analysis, the results obtained with the proposed method were compared with a DEM generated using the socet set next generation automatic terrain extraction (NGATE) program of BAE systems. Using the proposed method, the details of the terrain in the high-resolution surface normal image and the output DEM were well estimated.

可以使用单个图像和立体图像对的梯度从轨道器上的成像传感器或激光高度计传感器生成数字高程模型（DEM）。这些DEM受固有问题的影响，例如三角测量过程中的立体声噪声或来自稀疏测量点的低空间分辨率。当前使用各种基于图像的技术来增强DEM的分辨率，但是它们可能非常具有挑战性，因为从一个或多个部分重叠的图像计算每个表面点方向矢量需要许多假设。在本文中，提出了一种使用从正射校正后的行星图像数据集中提取的表面法线的信息来提高粗DEM分辨率的方法。从正射校正后的行星图像数据集中提取的表面法线与粗DEM很好地对齐，并且该表面法线还提供了每个表面点处质量均匀的方向矢量，此改进的关键是将表面法线作为地图，克服了表面方向信息在模糊性方面的作用。然后，使用高分辨率的曲面法线信息对粗DEM进行优化，以便在曲面法线图中显示地形的特征。为了进行性能分析，将使用该方法获得的结果与使用BAE系统的集集下一代自动地形提取（NGATE）程序生成的DEM进行比较。使用建议的方法，