Photogrammetry walkthrough

This document was written mostly by a Large Language model using the following prompt:

"I'd like you to help me write a guide on how to use photogrammetry software. The guide will be specifically about the OpenDroneMap (ODM) softwate, and Agisoft Metashape. You are an expert on writing detail oriented and pedagogically sound guides, and have sound knowledge of photogrammetry techniques. I will be here to help you in case you get something wrong, but you probably won't need that."

I used this prompt, and then went through each section suggesting changes and editing what the model suggested as text. The LLM was a bit rubbish- I mean basic- , but it did provide a structure that greatly helped me speed up writing this! This was written in a bit of a hurry so I apologise for any mistakes, I intend to update and improve this over time.

Introduction

Overview of Photogrammetry

Photogrammetry is the science of making measurements from photographs. It involves capturing multiple images of an object, structure, or area from different angles and using software to create accurate 2D or 3D models. This technique is widely used in fields such as surveying, architecture, engineering, and archaeology.

Intended Goals of This Document

This guide aims to provide a comprehensive overview of how to use OpenDroneMap (ODM) and Agisoft Metashape for photogrammetry. It will cover installation, basic workflows, advanced features, and practical applications. By the end of this guide, users should be able to confidently process aerial imagery into high-quality maps and 3D models using both software tools.

Introduction to OpenDroneMap (ODM)

OpenDroneMap (ODM) is an open-source photogrammetry toolkit that processes aerial imagery into maps, 3D models, and other geospatial data. It is designed to be accessible and flexible, making it a popular choice for hobbyists, researchers, and professionals. ODM supports a wide range of input formats and provides various output options, including orthophotos, point clouds, and digital elevation models (DEMs).

Pros:

Fully open-source and free to use
Supports a wide range of input formats
Generates various output options (orthophotos, point clouds, DEMs)
WebODM interface provides a user-friendly way to interact with ODM

Cons:

More difficult to install and navigate, especially for beginners
Primarily command-line based, which can be challenging for users unfamiliar with command-line interfaces
Limited official support, relying mostly on community forums

Introduction to Agisoft Metashape

Agisoft Metashape is a professional photogrammetry software that offers advanced tools for processing and analyzing aerial and close-range photogrammetry data. It is known for its high accuracy and robust feature set, including support for ground control points (GCPs), dense point cloud generation, and texture mapping. Metashape is widely used in industries such as construction, mining, and cultural heritage preservation.

Pros:

Intuitive and user-friendly interface
Comprehensive documentation and active user forums
Supports a wide range of advanced features (GCPs, dense point clouds, texture mapping)
Python API for automation and customization

Cons:

Proprietary software with a significant cost
Requires a powerful computer for optimal performance
Steeper learning curve for advanced features