What is Photogrammetry?

What is Photogrammetry?

Photogrammetry is the science and technology of obtaining reliable information about physical objects and the environment through the process of recording, measuring, and interpreting photographic images. Essentially, it allows for the creation of three-dimensional models or maps from two-dimensional photos. This technique has applications in various fields, from archaeology to urban planning, architecture, and even game development.

With the rise of photogrammetric tools and software, creating highly detailed 3D models has become easier and more accessible. Photogrammetry combines photography, geometry, and advanced algorithms to deliver models that are accurate and visually stunning.

In this article, we’ll dive into the basics of photogrammetry, how it works, and some simple examples that showcase its potential. We’ll also take a look at demo of my own photogrammetry model, Fotros, available on Hugging Face here, which demonstrates the process in action.

How Photogrammetry Works

At its core, photogrammetry relies on multiple photos taken from different angles of the same object or scene. By using triangulation, the software can calculate the distance and positions of points on the object from these images. Here’s a simplified breakdown of the process:

  1. Image Acquisition: Multiple photos are taken from different viewpoints. Ideally, the object or scene should be captured from various angles to ensure the maximum amount of detail is recorded.

  2. Processing: The photos are fed into photogrammetry software that analyzes the overlapping areas in the images. Key points (or "features") in the images are identified and matched across multiple photos.

  3. Triangulation: Using the positions of the cameras and the identified matching features in the photos, the software calculates the relative positions of these points in 3D space, effectively reconstructing the object.

  4. 3D Model Creation: Finally, the software generates a point cloud—a collection of 3D coordinates representing the object. These points can be further refined into a 3D mesh and textured to create a realistic 3D model.

Here is example of multiple photos taken from different angles of the same object:

List of the best photogrammetry apps

Here’s a list of the best photogrammetry apps:

  1. RealityCapture: A fast and efficient photogrammetry tool, popular for handling large datasets and high-resolution photos. It is used for creating highly accurate 3D models of landscapes and objects.

  2. Agisoft Metashape: A professional-grade software known for its high accuracy and flexibility, supporting small and large projects for industries like archaeology, architecture, and aerial mapping.

  3. 3DF Zephyr: A versatile photogrammetry tool that offers both free and paid versions. It is used to create precise 3D reconstructions of objects, buildings, and landscapes.

  4. Meshroom: An open-source photogrammetry tool that allows users to create detailed 3D models from photos. It is user-friendly and suitable for both beginners and professionals.

Real-World Application: Fotros

To showcase the power of photogrammetry, I developed a model called Fotros, which is available on Hugging Face. Fotros allows users to upload photos of an object from various angles, and it generates a 3D model using photogrammetry techniques.

This model is a practical example of how easy it can be to turn photos into 3D models. It uses Meshroom as the backend for photogrammetry and is integrated with advanced algorithms to make the process fast and accurate. It’s ideal for beginners and professionals alike who are interested in creating 3D models for augmented reality (AR), virtual reality (VR), and other visualizations.

Conclusion

Photogrammetry is an incredible tool that turns ordinary photos into precise 3D models, opening the door for countless applications. Whether you're documenting an archaeological site or creating 3D assets for video games, photogrammetry offers a powerful solution.

With models like Fotros, the process is becoming more accessible than ever. If you're interested in seeing photogrammetry in action, I encourage you to try out Fotros and start exploring the world of 3D modeling!