This document provides an overview of photogrammetry, which is the process of using photographs to measure and survey objects and landscapes. It discusses different types of photogrammetry like stereography and structure from motion (SfM). SfM uses photographs to build 3D models and can be used with images from any camera. The document also outlines common uses of photogrammetry in fields like geology, archaeology, and engineering. It provides guidance on capturing images for photogrammetry projects of objects, buildings, and interiors.

1. Photogrammetry
A Brief Primer

2. Objects:

3. Buildings

4. Landscapes:

5. Photogrammetry: Using photographs to survey
& measure distances between objects
Photogrammetry = Umbrella Term Over Things like:
• Stereography/Stereoscopy
• Stereoplotting (elevation contours on terrain maps)
• Structure From Motion (SfM)
• = Using photographs to build a 3D Model
• SfM = Umbrella Term Over Things like:
• “Stereographic Reconstruction” (How Vricon describes their stuff)
• Simultaneous Localization & Mapping (SLAM)
• Visual Odometry (when Robots SLAM)

6. • Structure from Motion (SfM)
• Can use images from any cameras, in any
order, at any scale (but typically applied esp
to close range)
• = crowdsourcable
• At 1:1 level = highest photogrammetry
resolution possible
• Industry preferred term in BIM, GEOINT,
Exploration & Museum sciences
Simultaneous Location & Mapping (SLAM)
• Performs SfM by use of metadata context vs.
edge recognition
• Can only use ordered images from same
camera
• Lower resolution because of mathematical
approximation
• Best used for kilometer+ swathes (order +
geospatial metadata help build, but don’t require precision)
• VR/AR community fondness for term (because
real time capture predicates use of same camera, low resolution
necessary in current engines)

7. Photogrammetry vs. Spatial Mapping in VR/AR
Thing to be aware of: Spatial Mapping focus isn’t on image capture, but bounding box/volume recognition
Uses cameras + near-infrared depth sensors for limited structured light scanning (SLS)
Examples: Spatial Mapping in Hololens

8. A Brief Note on the Infrared Spectrum

9. What is Photogrammetry Used For?
Aerial
• Terrain
Mapping
• Creating
Virtual
Landscapes
Terrestrial /1:1
• Rapid Replication
of Objects/Artifacts
• Creating Virtual
Landscapes
Time/Space Replicator

10. Who Uses Structure from Motion & Derivatives?
GEOINT
Exploration
& Surveying
Architecture
&
Infrastructure
Leisure
Building
Information
Modelling (BIM)
Roadworks
Structural
Engineering
Agricultural
Technology
(Agrotech)
Geology
Geosciences
Oil & Gas
Aerospace
Conservation
Anthropology
Marine Sciences
Meteorology
Gaming
Museums & Education
Virtual Tourism
Tourism
(organizational)
National Policy & Security
Digital Archaeology
(the group who’s had their fingers in the 2D +
3D pies in all of these categories the longest)
Film
Autonomous Vehicles

11. Quick How To Guide:
• What You’ll Need
• Camera (even phone camera is fine these days)
• Software
• Best:
• BIM Industry standard is Agisoft
• 2nd place: Autodesk Remake (formerly Autodesk 123D Catch & Autodesk Memento)
• RealityCapture
• Lots of open source versions
• Samantha (->Zephyr)
• Assorted MatLab pull-a-part-ables
• Patience

12. For An Object
Basic Object
Basic Object with
Higher Res Detail
Exs. From Bentley Photogrammetry Workflows

13. Height Rings Help:

14. If there’s not much texture/uniform texture:
• use a calibration mechanism
• ensure photo order to provide additional context

15. For A Building Exterior:
For just the front facade

16. Going Round Corners (More is Better)

17. Height Helps (But again, aren’t necessary, can fudge from human height)

18. For A Room Interior (the hardest)

19. If Using Drones:
• Maintaining photo sequence is crucial

20. For planes +
• Known/Precision overlap required

21. Once you’ve captured your images
• Get rid of any blurry or zoomed ones (these are non-helpful)
• Pop them into suitable software
• Push them through the automated workflow (or torture yourself in Matlab, your choice)
• Export in your desired format
• Yay!

22. How does Photogrammetry fit in with the rest
of the possibilities for Diagnostic Imaging?

23. Towards Ubiquitous Sensing
• But photogrammetry is only the beginning…..
• 3D Social Multimedia
• Diagnostic devices constantly getting cheaper
• (Visible Image camera as example)
• Rising demand for 3D Content
• -- Everyone constantly mapping the world in 3D
• Throw in machine learning analytics
• =Ubiquitous, Omniscient 3D Sensing & Mixed Reality Space
• =The Science Fiction Future will be upon us….
Shout out to my recent invited paper
on this re: National Security
preparation for this…