QGIS Nova Scotia & PEI LiDAR Processing Tool

A command-line tool for processing LiDAR data from Nova Scotia and Prince Edward Island using QGIS. This tool allows you to:

• Geocode addresses in Nova Scotia and PEI
• Download and process LiDAR point cloud data
• Extract building footprints from LiDAR data
• Generate satellite imagery for the location
• Visualize 3D point clouds

Features

• Address geocoding using OpenStreetMap Nominatim API
• Coordinate transformation between different CRS (WGS84, NAD83(CSRS), MTM zone 5)
• LiDAR point cloud processing using laspy
• Building point extraction
• 3D visualization capabilities
• Satellite imagery retrieval from Mapbox

Prerequisites

• Python 3.8 or higher
• QGIS 3.22.0 or higher
• Conda (required for QGIS installation)

Installation

The installation process has three steps: setting up QGIS, installing dependencies, and installing this package.

1. Install QGIS using Conda

First, create a new conda environment with QGIS installed:

# Create a new environment with QGIS and Python 3.8
conda create -n qgis-env -c conda-forge qgis python=3.8

# Activate the environment
conda activate qgis-env

2. Install Dependencies

Install required dependencies using conda:

conda install -c conda-forge pyproj numpy matplotlib
conda install -c conda-forge laspy lazrs

3. Install qgis-ns-pe

After activating the conda environment and installing dependencies, install this package:

# For users: install from PyPI (not yet available)
# pip install qgis-ns-pe

# For developers: install in editable mode from source
git clone https://github.com/amadgakkhar/qgis-ns-pe.git
cd qgis-ns-pe
pip install -e .

Package Structure

The package should have the following structure:

qgis-ns-pe/
├── qgis_ns_pe/
│   ├── __init__.py
│   └── cli.py
├── setup.py
└── README.md

Verification

To verify the installation:

# Make sure you're in the conda environment
conda activate qgis-env

# Try running the tool with --help
qgis-ns-pe --help

Usage

The tool can be used from the command line with the following syntax:

qgis-ns-pe --address "Your Address" --index_path "/path/to/lidar_index.gpkg" [--show_3d]

Example:

qgis-ns-pe --address "8 Alderwood Dr, Halifax, NS B3N 1S7" --index_path "/path/to/Index_LiDARtiles_tuileslidar.gpkg" --show_3d

Arguments

• --address: The address to process (required)
• --index_path: Path to the LiDAR index GPKG file (required)
• --show_3d: Optional flag to show 3D visualizations of the point clouds

Output

The tool creates two directories:

• lidar_tiles/: Contains downloaded LiDAR tiles
• output/: Contains processed files:
  • sat.png: Satellite image of the location
  • lidar_cropped.laz: Cropped LiDAR point cloud
  • buildings.laz: Extracted building points

Troubleshooting

Common issues and solutions:

1. QGIS not found: Make sure you've activated the conda environment with conda activate qgis-env
2. Import errors: Ensure you're running the tool from the conda environment where QGIS is installed
3. Missing dependencies: If you encounter any missing dependency errors, try installing them with conda first:

   conda install -c conda-forge <package-name>
   

Data Sources

• LiDAR data: Nova Scotia and PEI government open data portals
• Geocoding: OpenStreetMap Nominatim API
• Satellite imagery: Mapbox Static Images API

License

This project is licensed under the MIT License - see the LICENSE file for details.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Authors

• Amad Gakkhar - Initial work

Acknowledgments

• QGIS Development Team
• laspy contributors
• OpenStreetMap contributors
• Mapbox