This week’s selection is “Close-Range Photogrammetry and 3D Imaging” by Thomas Luhmann, Stuart Robson, Stephen Kyle and Jan Boehm.
Photogrammetry is one of the fundamental methods of 3D scanning, and it’s one that almost anyone can use without the need for sophisticated and often expensive scanning gear.
While 3D scanning hardware involves projecting beams of laser, visible or infrared light at a subject and interpreting the reflected results, photogrammetry is quite different.
Photogrammetry involves capturing a sequence of still images of the subject from a wide variety of angles. Then, sophisticated software reviews the large collection of images to develop a 3D model based on how the textures and structures within the image shift slightly from position to position.
Thus the only on-site 3D scanning equipment required is a competent camera, which almost everyone already owns. However, there is the matter of that “sophisticated software”, and the mysterious manner in which it develops the 3D model.
How Photogrammetry Works
That’s what this book is about: Photogrammetry from end-to-end. It begins with an overview of the process, but then branches into the sophisticated layers of photogrammetry that many people don’t understand. Often photogrammetry services and software are considered “black boxes” that do the job on their own.
After the detailed introduction, this book proceeds to explain the mathematical theory behind photogrammetry, which is critical to the process. You may not need to understand this part of photogrammetry, but it’s there in the book if you’re curious.
What’s more interesting to me are the subsequent chapters, which explain the process in exquisite detail. Subjects discussed include:
Image acquisition, specifically for close-range (meaning not aerial photography)
Analytical methods used for image analysis
Digital photogrammetric image processing
Types of photogrammetry systems: e.g., stereo imaging, single image, etc.
Photogrammetry project planning to achieve target quality
And there’s a bunch of case studies to show how the technology can actually be used in real life.
While many readers may already have a basic understanding of photogrammetry, this will take you far deeper into the technology and how it works. I believe this could be critically important for achieving quality results: if you understand what’s actually going on under the hood, then you may become a better photogrammetry operator.
That said, this book definitely is not for those just beginning on a photogrammetry journey; instead it is for those who have been performing photogrammetry and wish to take their skills up a notch by knowing a great deal more about how the technology works.