How to build a 3D model through post-processing measurement

Aug 16, 2023

Image control post-processing to build a high-precision 3D reality model is an image control post-processing mode that collects the coordinates of image control points through the existing high-precision 3D reality model, referred to as post-processing modeling mode, that is, if all or part of the high-precision 3D reality model has been built, At this time, points with significant marks, easy recognition in existing 3D reality models, and scientific and reasonable positions can be selected as image control points on the non-image control model, and the coordinate information of these points can be collected from the existing high-precision 3D reality model.

In the conventional layout method, the geographical position of the point is determined by laying a marking square or drawing a point mark, and then using a high-precision measuring instrument to collect the coordinate information of the image control point.

The post-processing measurement method combined with the actual geographical location of the distribution of the features, such as the center line of the road, the dividing line of the tile style and the ground indication mark, and other features with obvious geometric characteristics, were selected from the image-free model. Based on the image-free control model, the position and geometric information of pre-selected feature points can be clearly seen, without the need to carry out field point reconnaissance work. On the one hand, image control points can be scientifically laid and accurately determined; on the other hand, image control point marks do not need to be made and buried, which can effectively save costs and improve efficiency. After the control point is selected, the point coordinates of the feature points are collected by the high-precision measuring instrument.

The post-processing model measurement method selects the same position and number of ground object feature points as the image control points as the post-processing measurement method. The difference is that this method collects the coordinate information of image control points from the existing high-precision 3D reality model, without field measurement, and reduces the workload and cost in updating the local change area of the 3D reality model such as cities and towns. The efficiency of aerial survey modeling is improved.

The texture of the 3D real scene model after image control is realistic and clear, and the appearance is consistent with that of the conventional tape control model.