a few narrow bands or spikes. Note: An example of black noise in a facsimile transmission system is the spectrum that might be obtained when scanning a black area in which there are a few random white spots. Thus, in the time domain, a few random pulses occur while scanning. Noise with a spectrum corresponding to the blackbody radiation (thermal noise). For temperatures higher than about the peak of the blackbody spectrum is above the upper limit of human hearing range. In those situations, for the purposes of what is heard, black noise is well approximated as violet noise. At the same time, Hawking radiation of black holes may have a peak in hearing range, so the radiation of a typical stellar black hole with a mass equal to 6 solar masses will have a maximum at a frequency of 604.5 Hz - this noise is similar to green noise. A formula is: Hz. Several examples of audio files with this spectrum can be found here. Noisy white In telecommunication, the term noisy white has the following meanings: In facsimile or display systems, such as television, a nonuniformity in the white area of the image, i.e., document or picture, caused by the presence of noise in the received signal. A signal or signal level that is supposed to represent a white area on the object, but has a noise content sufficient to cause the creation of noticeable black spots on the display surface or record medium. Noisy black In telecommunication, the term noisy black has the following meanings: In facsimile or display systems, such as television, a nonuniformity in the black area of the image, i.e., document or picture, caused by the presence of noise in the received signal. A signal or signal level that is supposed to represent a black area on the object, but has a noise content sufficient to cause the creation of noticeable non-black spots on the display surface or record medium. Generation Coloured noise can be computer-generated by first generating a white noise signal, Fourier-transforming it, then multiplying the amplitudes of the different frequency components with a frequency-dependent function. Matlab programs are available to generate power-law coloured noise in one or any number of dimensions. See also Mains hum (also known as the AC power hum) Whittle likelihood References External links Some colored noise definitions Online Colored Noise Generator and True Grey Noise Generator Black