How to make central projection photos into conformal projection terrain in aerial photogrammetry

To get DLG line drawing, the main process is as follows:

1, aerial photography; Refers to aerial photography, which can be conventional film photography. So it is necessary to scan the image and turn it into a digital image. It can also be digital photography and ADS40. ..

2, empty three encryption; The current technology can realize photography without ground control or with a small amount of ground control, that is, auxiliary space 3 with GPS inertial navigation device.

3. Surveying and mapping in the industry; On the photogrammetry workstation, 3D models and ground objects (such as residential areas, water systems, roads, vegetation, etc.) are restored by using the original images and the results of aerial 3D encryption. ) and geomorphological features (such as contour lines and gullies, etc.). ) are collected in three dimensions.

4. Field mapping; After the collection of ground objects is completed, you can print out the surveying and mapping films according to the required scale, and make qualitative surveying and mapping on the spot, such as vegetation types and names of residential areas. There are also new features added after photography.

5. Internal investigation; Fill the field surveying and mapping features into the indoor surveying and mapping data, complete the editing of geometry and attributes, and sort out some symbolic features (such as vegetation). ) and exterior decoration.

6. Drawing;

All the above work is done by professional surveying and mapping software, such as calibration and scale setting.