Photogrammetry for Product Design and AEC

- [Instructor] There are many types of photogrammetry. And after watching this video, you'll be able to distinguish between several different approaches including the one we'll use in this course. In a literal sense, photogrammetry means extracting measurements from photographic images. The original definition is tied to uses in surveying and mapping. We can see an example of an early photogrammetry technique in the image on the left where a grid called a perspectometer is superimposed over the image. This was helpful in producing topographic maps of landscape features. Advancements in mathematics, optical sensing, and computer hardware and software have allowed for many variations on these basic measuring techniques. This includes highly accurate three-dimensional measurements of objects, such as the computer tomography or CT scan in the center image. This type of photogrammetry combines x-ray images into three dimensional representations of internal body structures. Another example of a photogrammetry technique can be seen in the image on the right, which is a 3D representation of a landscape made using LIDAR, a technology that combines lasers and other sensor data to make high resolution models of landscapes, buildings, archeological sites, and other relatively large objects. This course is focused on reconstructing accurate 3D models and textures from photographs of relatively small scale objects. Here, you can see an example of a 3D reconstruction of a bird figurine constructed from about 30 individual photographs represented by the blue rectangles. When we use the word photogrammetry in this course we'll be referring specifically to this sort of approach. But just know for future reference that there are many fascinating variations on our process that still count as photogrammetry.