drawArrow: Draw Arrows on an 'Image'

In swarm-lab/Rvision: Computer Vision Library for R

Draw Arrows on an Image

Description

drawArrow draws arrow segments from the first point to the second over an Image object. This operation is destructive: it changes irreversibly the Image object and cannot be undone.

Usage

drawArrow(
  image,
  pt1_x,
  pt1_y,
  pt2_x,
  pt2_y,
  tip_length = 0.1,
  color = "red",
  thickness = 1
)

Arguments

image	An Image object.
pt1_x	A numeric value or vector representing the x coordinates of the first end of each arrow.
pt1_y	A numeric value or vector representing the y coordinates of the first end of each arrow.
pt2_x	A numeric value or vector representing the x coordinates of the second end of each arrow.
pt2_y	A numeric value or vector representing the y coordinates of the second end of each arrow.
tip_length	A numeric value or vector representing the length of each arrow's tip as a fraction of each arrow's length (default: 0.1).
color	A value or vector of any kind of R color specification compatible with col2bgr representing the color of each arrow (default: "red").
thickness	A numeric value or vector representing the thickness in pixels of each arrow (default: 1).

Value

This function does not return anything. It modifies image in place.

Author(s)

Simon Garnier, [e-mail]

See Also

Image, drawLine

Examples

balloon <- image(system.file("sample_img/balloon1.png", package = "Rvision"))
drawArrow(balloon, 1, 1, ncol(balloon) / 2, nrow(balloon) / 2, thickness = 3)

swarm-lab/Rvision documentation built on Feb. 7, 2024, 4:59 a.m.