Difference between revisions of "Artifact"

From Hydrogenaudio Knowledgebase
Jump to: navigation, search
(Different kind of artifacts)
(External links)
 
(4 intermediate revisions by 2 users not shown)
Line 3: Line 3:
  
  
 
+
===Common artifacts===
===Different kind of 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".  
 
* '''[[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:
+
:''Illustrative samples'': [http://www-ccrma.stanford.edu/~bosse/ castanets.wav], [http://anonymousriver.hp.infoseek.co.jp/castanets2/index.html castanets2.wav]
[[Image:Preecho.png]]
+
  
To listen to the corresponding artifact, click [[http://audiotests.free.fr/tests/wiki/castanets2.mp3 here]]
+
: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''':
 
* '''ringing''':
 +
  
 
* '''warbling''':  
 
* '''warbling''':  
 +
  
 
* '''coarseness''':
 
* '''coarseness''':
 +
  
 
* '''stereo collapse''':
 
* '''stereo collapse''':
 +
  
 
===External links===
 
===External links===
*[http://ff123.net/training/training.html ff123's Audio Artifact Training Page]
+
*<s>ff123's Audio Artifact Training Page</s>
 +
 
  
 
{{stub}}
 
{{stub}}
 +
 +
 +
[[Category:Listening Tests]]

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:
Preecho.png
To listen to the corresponding artifact, click here


  • ringing:


  • warbling:


  • coarseness:


  • stereo collapse:


External links

  • ff123's Audio Artifact Training Page