Welcome to alproj’s documentation!

alproj is a simple python package for geo-rectification of alpine landscape photographs.

alproj has 3 steps for geo-rectification of a landscape photograph.

1. Setting Ground Control Points (GCPs) in target photographs, using simulated landscape images rendered with Digital Surface Models and airborne photographs.

2. Heuristic estimation of camera parameters including the camera angle, field of view, and lens distortions (shooting point of the photograph is required).

3. Perspective reverse projection of the target photograph on Digital Surface Model, with estimated camera parameters, using OpenGL.

This project aims to revive alpine landscape photographs in your photo albams, as valuable geospatial data that may reveal the unknown changes of alpine landscape, ecosystem and cryosphere!

Tip

Looking for a GUI? Try alproj-gui — a desktop application for georectification, no coding required.

Contents:

• Installation
  • Basic Installation
  • Optional Dependencies
  • Dependencies
  • Tested environments
• Overview
  • Algorithm
  • The Camera Model
  • Future applications in alpine ecology, geology, and glaciology
• Usage
  • Data Preparation
  • Loading Raster Data
  • Define Initial Camera Parameters
  • Rendering a Simulated Landscape Image
  • Finding Ground Contorol Points
  • Optimization of Camera Parameters
  • Reverse Projection
  • Exporting to GeoTIFF
• Matching Methods Gallery
  • Built-in Methods (No Extra Dependencies)
  • LightGlue-based Methods (Lightweight)
  • Dense Matching Methods (High Match Count)
  • Cross-Modal Methods (Robust to Appearance Changes)
• Camera Model Comparison
  • When to Use Which Model
  • Simulation Overlay
  • Matching Results
  • Reprojection Error
  • Quick Start: Fisheye Model

Package Reference:

• alproj.surface module
  • get_colored_surface()
• alproj.project module
  • modelview_mat()
  • persp_proj()
  • projection_mat()
  • reverse_proj()
  • sim_image()
  • to_geotiff()
• alproj.gcp module
  • filter_gcp_distance()
  • image_match()
  • plot_matches()
  • set_gcp()
• alproj.optimize module
  • BaseOptimizer
  • CMAOptimizer
  • LsqOptimizer
  • bounds_to_array()
  • compute_residuals()
  • extrinsic_mat()
  • huber_loss()
  • intrinsic_mat()
  • mean_reprojection_error()
  • project()
  • rmse()

Indices and tables

• Index

• Module Index

• Search Page