White noise generator — noise

White noise is a random noise with equal intensities at different frequencies. It is most well-known as what appeared on old televisions when no signal was found.

noise_white(
  dim,
  frequency = 0.01,
  pertubation = "none",
  pertubation_amplitude = 1
)

gen_white(x, y = NULL, z = NULL, t = NULL, frequency = 1, seed = NULL, ...)

Arguments

dim	The dimensions (height, width, (and depth, (and time))) of the noise to be generated. The length determines the dimensionality of the noise.
frequency	Determines the granularity of the features in the noise.
pertubation	The pertubation to use. Either `'none'` (default), `'normal'`, or `'fractal'`. Defines the displacement (warping) of the noise, with `'normal'` giving a smooth warping and `'fractal'` giving a more eratic warping.
pertubation_amplitude	The maximal pertubation distance from the origin. Ignored if `pertubation = 'none'`. Defaults to `1`.
x, y, z, t	Coordinates to get noise value from
seed	The seed to use for the noise. If `NULL` a random seed will be used
...	ignored

Value

For noise_white() a matrix if length(dim) == 2 or an array if length(dim) >= 3. For gen_white() a numeric vector matching the length of the input.

Examples

# Basic use
noise <- noise_white(c(100, 100))

plot(as.raster(normalise(noise)))


# Using the generator
grid <- long_grid(seq(1, 10, length.out = 1000), seq(1, 10, length.out = 1000))
grid$noise <- gen_white(grid$x, grid$y)
plot(grid, noise)