数字地貌晕渲的主观特征塑造与视觉适宜度分析

Digital relief shading is visual representation of the landform based on DEM and plays a crucial role in shaded relief map as the basis and support for geographic features. Researches show that there is some widespread inadequate performance in such aspects as shaping of subjective features, suitability assessment and adaptive processing among existing digital shading methods. In this research, at first, the structure of landforms characteristic lines and terrain surface strips are analyzed based on DEM, and then a hierarchical framework consisting of many sub terrains is constructed with each sub terrain being organized in triangular irregular mesh. After repeated experiments, the indexes system of terrain complexity assessment relevant to spatial scale is established and the parameters of remodeling local landform based on network of terrain surface strips, which includes weight factor and buffer coefficient, and filtering methods of DEM are explored and the basic approach by which shapes exaggeratedly the typical landforms features and weakens other minor parts is studied. In addition, through studying visual complexity, the regularity and potential relationship between the DEM resolution and representing scale of relief shading are revealed. Finally, based on Computer Vision, information entropy theory and subjective evaluation method in Psychology, the project will studied the visual suitability computation and evaluation of shaded-relief map. The project proposes and explores the problems of subjective geomorphic features reshaping and visual suitability analysis in relief shading, which aims at providing new ideas for automatic implementation of shading with artificial styles, scale adaption of visual complexity and intelligent processing of relief shading.

数字地貌晕渲是基于DEM对地貌的直观表现，是晕渲地形图中地理要素的基础和依托，至关重要。研究发现现有的数字晕渲方法普遍存在主观地貌特征表现不足与无法进行适宜度评估以及自适应处理等问题。本研究首先基于DEM进行地貌特征线与地形面片结构分析，建立基于地形子面片三角网模型的层次模型，经反复试验确定与尺度相关的地形复杂度评估指标体系，探讨基于地形面片网络的地貌塑造参数（即权重因子与缓冲系数）与DEM滤波方法，研究典型地貌特征的夸张塑造与次要形态弱化的基本途径。同时通过视觉复杂度的研究，揭示DEM分辨率与地貌晕渲特征表现尺度之间的规律与潜在关系，并基于计算机视觉与信息熵理论、心理学主观评价方法对数字晕渲地图的视觉适宜度进行评估研究。本项目首次提出并探讨地貌晕渲的主观特征塑造与视觉适宜度分析问题，以期为人工晕渲风格的自动实现及视觉复杂度的尺度自适应问题、数字地貌晕渲的智能化处理提供新的思路。

项目研究地貌晕渲的主观特征塑造与视觉适宜度分析问题，目的在于为人工晕渲风格的自动实现及视觉复杂度的尺度自适应问题、数字地貌晕渲的智能化处理提供新的思路，具有重要的实践价值。项目主要研究数字地貌特征线与特征子区域的层次化指标体系及其尺度变化规律、基于区域地貌特征与面片结构分析的典型特征塑造、数字地貌晕渲图的视觉复杂度分析及其与表现尺度的适宜性评价和顾及特征塑造与视觉适宜性的数字地貌晕渲自动重塑处理机制。. 项目根据计划的研究目标展开研究，通过对基于 DEM的数字地貌分析与特征线层次树研究，揭示了地貌特征在数字晕渲中的控制性作用，构建了DEM 尺度与地貌晕渲可视化尺度两者之间的对应关系模型，研究了区域地貌特征的重塑方法，形成基于地形面片结构及其地形因子指标体系的地貌晕渲信息量传输、评价及视觉适宜度评价分析的基本思路，为构建与区域地貌特征相匹配的地貌晕渲特征重塑及评价提供了有效的途径。. 已发表期刊论文10篇，会议论文2篇，获批软件著作权1项。基本达到项目预定的研究目标。