Artifact: Difference between revisions

Latest revision as of 06:26, 13 September 2013

An artifact is a noticeable difference between an uncompressed signal and a lossily-compressed copy. Lossy encoding can result in very different kind of artifacts/distortions. Sometimes it's not easy to define why the encoding is non-transparent. There are however many typical encoding artifacts.

Common artifacts

pre echo: pre-echo consists in a small amount of noise used to appear just before a contrasted sound events (like percussive instruments). The original transients are therefore smeared: "___shhhTak" instead of "____Tak".

Illustrative samples: castanets.wav, castanets2.wav

The phenomenon could sometimes be visualised on a frequency editor:

To listen to the corresponding artifact, click here

ringing:

warbling:

coarseness:

stereo collapse:

External links

~~ff123's Audio Artifact Training Page~~

This article is a stub. You can help the Hydrogenaudio Knowledgebase by expanding it.

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-An '''artifact''' is a noticeable difference between an uncomressed signal and a [[lossy|lossily]]-compressed copy.
+An '''artifact''' is a noticeable difference between an uncompressed signal and a [[lossy|lossily]]-compressed copy.
+[[Lossy]] encoding can result in very different kind of artifacts/distortions. Sometimes it's not easy to define why the encoding is non-transparent. There are however many typical encoding artifacts.
-==External links==
-*[http://ff123.net/training/training.html ff123's Audio Artifact Training Page]
+===Common artifacts===
+* '''[[pre echo]]''': pre-echo consists in a small amount of noise used to appear just before a contrasted sound events (like percussive instruments). The original transients are therefore smeared: "___shhhTak" instead of "____Tak".
+:''Illustrative samples'': [http://www-ccrma.stanford.edu/~bosse/ castanets.wav], [http://anonymousriver.hp.infoseek.co.jp/castanets2/index.html castanets2.wav]
+:The phenomenon could sometimes be visualised on a frequency editor:
+:[[Image:Preecho.png]]
+:''To listen to the corresponding artifact, click [http://audiotests.free.fr/tests/wiki/castanets2.mp3 here]''
+* '''ringing''':
+* '''warbling''':
+* '''coarseness''':
+* '''stereo collapse''':
+===External links===
+*<s>ff123's Audio Artifact Training Page</s>
+{{stub}}
+[[Category:Listening Tests]]