Photogrammetry is the science of making measurements from photographs, especially for recovering the exact positions of surface points. We use stereo photogrammetry using latest high-resolution aerial imagery to capture our 3D Models. To explain this fairly complicated process of X Y Z mapping in very few words, as survey plane flies over a city area, it takes series of photographs which overlap by 60%. With each photograph its GPS position, height, tilt, pitch and roll are recorded. Using this data + camera calibration data (to eliminate lens distortion effects), the imagery is triangulated to its correct real-world coordinates.
Once the source aerial imagery is triangulated we can finally start with the capture process. In areas where two images overlap, we project one image into one eye, the second image into another eye and and this way we are able to see the Z value (depth).