Difference between revisions of "Lossy compression"

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Perceptual  Algorithms are designed to remove information that humans will not notice.
 
Perceptual  Algorithms are designed to remove information that humans will not notice.
  
== Subsampling ==
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Lossy processes include:
Subsampling exploits the fact that humans are more sensitive to luminance than chrominance (color). The [[JPEG]] algorithm (amongst others) uses [[subsampling]] to throw away color information. Although color information is lost, it is difficult for humans to percieve the difference between the original image and an image with subsampled color. Of course this is dependent on the level of subsampling. Commonly used image subsampling values are / 2, / 4, / 8. Subsampling is used in all modern video codecs.
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* [[Subsampling]]
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* [[Quantization]]
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[[Category:Multimedia Terminology]]

Latest revision as of 16:27, 8 June 2007

Lossy compression uses perceptual coding to throw away data. Perceptual coding refers to generally two systems:

  1. The human vision system.
  2. The human auditory system.

Perceptual Algorithms are designed to remove information that humans will not notice.

Lossy processes include: