README.md

In softloud/droneland: Calculate the area of land captured by a drone image

droneland

The goal of droneland is to calculate the area of land captured by a drone image, using the method outlined in this manuscript.

Why do we care? Because ecological abundance is modelled using observed animeeple / land area.

Installation

You can install the development version from GitHub:

# install.packages("devtools")
devtools::install_github("softloud/droneland")

Example

Suppose we have a drone image of 7952 x 5304 pixels taken from 200 metres with a camera angled at 25 degrees with a vertical field of view of 38 degrees and a horizontal field of view of 54 degrees. Then the area of land captured, in metres, is

library(droneland)

drone_image_area(
  camera_angle = 25,
  vertical_fov = 38,
  horizontal_fov = 54,
  height = 200,
  pixel_row = 7952,
  pixel_col = 5304
)
#> [1] 105366.1

# dimensions of trapezoid

drone_image_area(
  camera_angle = 25,
  vertical_fov = 38,
  horizontal_fov = 54,
  height = 200,
  pixel_row = 7952,
  pixel_col = 5304,
  dim = TRUE
) %>% purrr::map(round)
#> $height
#> [1] 299
#> 
#> $width_closest
#> [1] 200
#> 
#> $width_furthest
#> [1] 505

Diagrams of angles and derivations

Check my derivations, please and thank you :)

In the derivations there are diagrams to check what angles to input.

Cite this package

citation("droneland")
#> 
#> To cite package 'droneland' in publications use:
#> 
#>   Charles T. Gray, Matthew Grainger and Hao Ye (2021). droneland:
#>   Calculate the area of land captured by a drone image. R package
#>   version 0.1.0.
#> 
#> A BibTeX entry for LaTeX users is
#> 
#>   @Manual{,
#>     title = {droneland: Calculate the area of land captured by a drone image},
#>     author = {Charles T. Gray and Matthew Grainger and Hao Ye},
#>     year = {2021},
#>     note = {R package version 0.1.0},
#>   }

softloud/droneland documentation built on Dec. 23, 2021, 3:31 a.m.