Limestone building facades: A proposal for soiling inspection method by photogrammetry

The research hypothesizes that limestone facade soiling can be quantitatively assessed through photogrammetry. To support this, architectural drawings in the DWG file were utilized as the background of this work. The methodology involved processing raw photographs into standardized "base facade images" – perspective corrected, gray-scaled, grey-equalized, resized to match the dimensions from the drawing files, and cleaned to eliminate all unrelated elements. These base facade images are created in the PSB files of elevations. Extracted PNG base facade images of all facade parts are stored in the "Base Facade Images" file. The accompanying "Calculation_of_soiling" file details the quantitative results obtained by applying the described photogrammetry method (specifically pixel counting on these base images) to the Kuledibi Treasury Building.本研究提出假设：可通过摄影测量（photogrammetry）对石灰岩立面污垢开展定量评估。为验证该假设，本研究采用DWG格式的建筑图纸作为研究支撑背景。研究方法涵盖将原始照片处理为标准化的基础立面图像（base facade images）：对原始照片进行透视校正、灰度化、灰度均衡，调整尺寸以匹配图纸文件中的尺寸规格，并去除所有无关元素。此类基础立面图像存储于立面视图的PSB文件中。提取得到的各立面部件的便携式网络图形（Portable Network Graphics）格式基础立面图像，均存储于名为"Base Facade Images"的文件中。配套的"Calculation_of_soiling"文件详细记录了将上述摄影测量方法（具体为在上述基础立面图像上开展像素计数操作）应用于库莱迪比国库大楼后得到的定量评估结果。