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:
“While we were thus engaged in the twilight, we heard faintly, from far down the stream, what sounded like two strokes of a woodchopper’s axe, echoing dully through the grim solitude.... When we told Joe of this, he exclaimed, “By George, I’ll bet that was a moose! They make a noise like that.” These sounds affected us strangely, and by their very resemblance to a familiar one, where they probably had so different an origin, enhanced the impression of solitude and wildness.”
—Henry David Thoreau (1817–1862)
“I throw myself down in my chamber, and I call in, and invite God, and his Angels thither, and when they are there, I neglect God and his Angels, for the noise of a fly, for the rattling of a coach, for the whining of a door.”
—John Donne (c. 1572–1631)