Difference between revisions of "Transparency"

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(input data matters as well)
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In [[psychoacoustics]], '''transparency''' is the ideal result of [[lossy]] data compression. If a lossily compressed result is perceptually indistinguishible from the uncompressed input, then the compression can be declared to be transparent. In other words, transparency is the situation where [[artifact]]s are nonexistant or imperceptible.
 
In [[psychoacoustics]], '''transparency''' is the ideal result of [[lossy]] data compression. If a lossily compressed result is perceptually indistinguishible from the uncompressed input, then the compression can be declared to be transparent. In other words, transparency is the situation where [[artifact]]s are nonexistant or imperceptible.
  
Transparency, like sound quality, is subjective. It depends most on the listener's familiarity with artifacts, and to a lesser extent, the compression method, [[bitrate]] used, listening conditions, and listening equipment.  
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Transparency, like sound quality, is subjective. It depends most on the listener's familiarity with artifacts, and to a lesser extent, the compression method, [[bitrate]] used, input characteristics, listening conditions, and listening equipment.  
  
 
Judging transparency can be difficult due to observation bias, in which subjective like/dislike of a certain compression methodology emotionally influences his/her judgment. This bias is commonly referred to as ''placebo,'' although this use is slightly different from the medical use of the term.
 
Judging transparency can be difficult due to observation bias, in which subjective like/dislike of a certain compression methodology emotionally influences his/her judgment. This bias is commonly referred to as ''placebo,'' although this use is slightly different from the medical use of the term.

Revision as of 04:57, 15 September 2006

In psychoacoustics, transparency is the ideal result of lossy data compression. If a lossily compressed result is perceptually indistinguishible from the uncompressed input, then the compression can be declared to be transparent. In other words, transparency is the situation where artifacts are nonexistant or imperceptible.

Transparency, like sound quality, is subjective. It depends most on the listener's familiarity with artifacts, and to a lesser extent, the compression method, bitrate used, input characteristics, listening conditions, and listening equipment.

Judging transparency can be difficult due to observation bias, in which subjective like/dislike of a certain compression methodology emotionally influences his/her judgment. This bias is commonly referred to as placebo, although this use is slightly different from the medical use of the term.

There is no way to prove whether a certain compression methodology is transparent. To scientifically prove that a compression method is not transparent, double-blind tests may be useful. The ABX method is normally used.