How is a point cloud created?

A point cloud is created through a process that captures a space or object in three dimensions, using various methods, including photogrammetry.

Point Cloud Creation Through Photogrammetry

Photogrammetry is a common method used to generate point clouds. Here's how it works:

Image Capture: Multiple cameras are used to capture images of the object or space from all angles. The goal is to obtain a comprehensive view from various perspectives.
Software Processing: Specialized software is then employed to process these captured images. The software analyzes the images to identify common features and reconstruct the scene in 3D.
Point Cloud Generation: The software processes the images and outputs a 3D point cloud, which consists of numerous individual point data sets representing the object or space. Each point in the cloud has 3D coordinates (x, y, z).

Accuracy: The accuracy of the point cloud largely depends on the quality and quantity of the input images. The more overlapping images captured from various viewpoints, the more accurate and detailed the resulting point cloud.
Software: Photogrammetry software algorithms are complex, relying on techniques such as structure from motion and bundle adjustment to accurately solve for the 3D geometry.
Applications: Point clouds find use in numerous fields, such as 3D modeling, surveying, and robotics, as they provide a foundation for these and other applications.

Imagine you're creating a 3D model of a building. You would:

Take photographs of the building from multiple locations and angles.
Upload the photos into photogrammetry software.
The software processes these images to create a 3D point cloud representation of the building.

While photogrammetry is a significant method, other techniques exist for creating point clouds, such as:

LiDAR (Light Detection and Ranging): This uses laser scanners to measure distances to objects and generate point cloud data.
Structured Light Scanning: This involves projecting a known light pattern onto an object and analyzing the distortion of the pattern to create a 3D map.
Time-of-Flight (TOF) Cameras: These cameras measure the time it takes light to travel to an object and back to determine depth information, allowing point cloud generation.