Useful Noise
High levels of noise are almost always undesirable, but there are cases when a certain amount of noise is useful, for example to prevent discretization artifacts (color banding or posterization). Some noise also increases acutance (apparent sharpness). Noise purposely added for such purposes is called dither; it improves the image perceptually, though it degrades the signal-to-noise ratio.
Read more about this topic: Image Noise
Famous quotes containing the word noise:
“The noise of battle hurtled in the air,
Horses did neigh, and dying men did groan,
And ghosts did shriek and squeal about the streets.”
—William Shakespeare (1564–1616)
“I live in the angle of a leaden wall, into whose composition was poured a little alloy of bell-metal. Often, in the repose of my mid-day, there reaches my ears a confused tintinnabulum from without. It is the noise of my contemporaries.”
—Henry David Thoreau (1817–1862)