has this property: all steeper power-law spectra are finite if integrated to the high-frequency end, and all flatter power-law spectra are finite if integrated to the DC, low-frequency limit. Brownian noise Brownian noise, also called Brown noise, is noise with a power density which decreases 6.02 dB per octave with increasing frequency (frequency density proportional to 1/f) over a frequency range excluding zero (DC). Brownian noise can be generated with temporal integration of white noise. "Brown" noise is not named for a power spectrum that suggests the color brown; rather, the name derives from Brownian motion. Also known as "random walk" or "drunkard's walk". "Red noise" describes the shape of the power spectrum, with pink being between red and white. Blue noise Blue noise is also called azure noise. Blue noise's power density increases 3.01 dB per octave with increasing frequency (density proportional to f ) over a finite frequency range. In computer graphics, the term "blue noise" is sometimes used more loosely as any noise with minimal low frequency components and no concentrated spikes in energy. This can be good noise for dithering. Retinal cells are arranged in a blue-noise-like pattern which yields good visual resolution. Cherenkov radiation is a naturally occurring example of almost perfect blue noise, with the power density growing linearly with frequency over spectrum regions where the permeability of index of refraction of the medium are approximately constant. The exact density spectrum is given by the Frank–Tamm formula. In this case, the finiteness of the frequency range comes from the finiteness of the range over which a material can have a refractive index greater than unity. Cherenkov radiation also appears as a bright blue color, for these reasons. Artistic approaches in soundwalk design and soundscape studies have appropriated the term of "blue noise" for describing water sounds. For example, as part of the events surrounding Esch2022 - European Capital of Culture, Swiss urbanist Trond Maag and sound gardener Andres Bosshard have designed soundwalk routes through the everyday acoustic environment of Esch and Belval, which are intended to invite the walkers/listeners to discover their urban surroundings in a new way (in collaboration with Administration de l’environnement Luxembourg, Université du Luxembourg, and Ville d’Esch-sur-Alzette). Violet noise Violet noise is also called purple noise. Violet noise's power density increases 6.02 dB per octave with increasing frequency "The spectral analysis shows that GPS acceleration errors seem to be violet