AIS visualization TASK

Introduction

• 

  The map and some coordinates

• 

  The map shall be transformed to photo

The position of vessels on a photo.

Data acquisition

USE RTL-AIS, ship162 (https://github.com/xoolive/ship162) project and Python, with tape measure antenna.

Transform

Some ideas to generate the transformation. Full camera projection is not needed here.

Homology

https://docs.opencv.org/4.x/d9/dab/tutorial_homography.html

The simplest; ${\begin{bmatrix}u\\v\\1\end{bmatrix}}{\tilde {=}}H{\begin{bmatrix}x\\y\\1\end{bmatrix}}$

Should have some 10-50 corresponding pairs to get the mapping correct. Use least squares or SVD, but OpenCV works with RANSAC.

Non rigid spatial warp

Thin plate spline, $(u,v)=f(x,y)$ where $f(x,y)=a_{1}+a_{2}x+a_{3}z+\sum _{i}w_{i}U(|p-p_{i}|)$ and $U(r)=r^{2}\log r$