Lossy: Difference between revisions

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'''Lossy''' compression is a form of compression that significantly reduce multimedia file size by throwing away information imperceptible to humans.
'''Lossy''' compression is a form of compression that significantly reduce multimedia file size by throwing away information imperceptible to humans.


Human audio perception is not perfect. Lossy compression takes advantage of this characteristics. By selective discarding, much unnecessary information is thrown away. The amount of information discarded is usually adjustable, giving a compromise between small size bad quality and high quality large size.
Human audio perception is not perfect. Lossy compression takes advantage of this characteristic. By selective discarding, much unnecessary information is thrown away. The amount of information discarded is usually adjustable, giving a compromise between smaller size with less quality and larger size with higher quality.


The downside to this is that waveform reconstructed from compressed information will never exactly match the original waveform.
The downside to this is that waveform reconstructed from compressed information will never exactly match the original waveform.

Revision as of 21:19, 10 May 2010

Lossy compression is a form of compression that significantly reduce multimedia file size by throwing away information imperceptible to humans.

Human audio perception is not perfect. Lossy compression takes advantage of this characteristic. By selective discarding, much unnecessary information is thrown away. The amount of information discarded is usually adjustable, giving a compromise between smaller size with less quality and larger size with higher quality.

The downside to this is that waveform reconstructed from compressed information will never exactly match the original waveform.

Does Lossy Encoding Preserve Surround Information?

Depending on the encoder and settings, degradation of surround imaging may happen. Use higher bitrate to prevent this from happening. Mid/Side stereo of LAME or AAC does not destroy surround information. Also MPC preserves surround information with standard settings reasonably well. The lower the bitrate, the worse you can expect the surround imaging become.

List of common lossy formats

See Also