ABC/HR - Revision history

Dynamic: /* Difference with ABX */ changed "subjective bias" to "personal bias" as with previous minor edit in previous section

2007-05-15T21:20:03Z

Difference with ABX: changed "subjective bias" to "personal bias" as with previous minor edit in previous section

← Older revision		Revision as of 21:20, 15 May 2007
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	==Difference with [[ABX]]==		==Difference with [[ABX]]==
	[[ABX]] is used to detect audible differences blindly, thereby removing ~~subjective~~ bias or the placebo effect and, over multiple trials, estimating the probability that the tester was guessing.		[[ABX]] is used to detect audible differences blindly, thereby removing personal bias or the placebo effect and, over multiple trials, estimating the probability that the tester was guessing.

	While an ABC/HR tool can do the same, it adds to that the ability to provide a quality rating on a standardized scale, and multiple participants' results can be statistically evaluated to estimate error bars and statistical significance of differences between encoders or encoder parameters in ranking their quality or tying them.		While an ABC/HR tool can do the same, it adds to that the ability to provide a quality rating on a standardized scale, and multiple participants' results can be statistically evaluated to estimate error bars and statistical significance of differences between encoders or encoder parameters in ranking their quality or tying them.

Dynamic: /* Purpose */

2007-05-15T21:18:59Z

Purpose

← Older revision		Revision as of 21:18, 15 May 2007
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	==Purpose==		==Purpose==
	Blind comparison and blind quality rating to remove the effects of ~~subjective~~ bias and the [[placebo effect]].		Blind comparison and blind quality rating to remove the effects of personal bias and the [[placebo effect]].

	==Difference with [[ABX]]==		==Difference with [[ABX]]==

Dynamic: /* Standardized quality scale */

2007-05-01T23:15:29Z

Standardized quality scale

← Older revision		Revision as of 23:15, 1 May 2007
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	===Standardized quality scale===		===Standardized quality or impairment scale===

	It is most common to use the 1.0 to 5.0 scale defined by <span style="color:red">?????</span>. Any value (including fractions) between 1.0 and 5.0 is valid, with the exact whole number representing the following definitions:
	* 5.0 :
	* 4.0 :
	* 3.0 :
	* 2.0 :
	* 1.0 :

			It is most common to use the 1.0 to 5.0 scale defined by [http://www.hydrogenaudio.org/forums/index.php?showtopic=53107 ITU-R BS.1116]. Any value (including fractions) between 1.0 and 5.0 is valid, with the exact whole number representing the following definitions to describe that degree of impairment:
			* 5.0 : Imperceptible
			* 4.0 : Perceptible, but not annoying
			* 3.0 : Slightly annoying
			* 2.0 : Annoying
			* 1.0 : Very annoying

	==References==		==References==

Pepoluan: Darn, forgot the wikilink syntax

2007-04-29T20:04:29Z

Darn, forgot the wikilink syntax

← Older revision		Revision as of 20:04, 29 April 2007
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	It is a method to 'score' the quality of audio encodings by comparing them alongside a reference sample. The 'hidden' comes from the fact that the listener does not know which sample -- the left or the right one -- is the reference.		It is a method to 'score' the quality of audio encodings by comparing them alongside a reference sample. The 'hidden' comes from the fact that the listener does not know which sample -- the left or the right one -- is the reference.

	The reference used usually is a sample of higher quality than the tested samples, e.g. uncompressed/[[losslessly~~\|lossless~~]] compressed audio tracks, or a [[lossily~~\|lossy~~]] compressed track with higher [[bitrate]].		The reference used usually is a sample of higher quality than the tested samples, e.g. uncompressed/[[lossless\|losslessly]] compressed audio tracks, or a [[lossy\|lossily]] compressed track with higher [[bitrate]].

Pepoluan: Many new things

2007-04-29T20:03:34Z

Many new things

@@ Line 1: / Line 1: @@
 '''ABC/HR''' is an abbreviation of ABC/Hidden Reference.
 It is a method to 'score' the quality of audio encodings by comparing them alongside a reference sample. The 'hidden' comes from the fact that the listener does not know which sample -- the left or the right one -- is the reference.
-The reference used usually is a sample of higher quality than the tested samples, e.g. uncompressed/losslessly compressed audio tracks, or a lossily compressed track with higher bitrate.
+The reference used usually is a sample of higher quality than the tested samples, e.g. uncompressed/[[losslessly|lossless]] compressed audio tracks, or a [[lossily|lossy]] compressed track with higher [[bitrate]].
 {{stub}}

Pepoluan at 14:02, 12 April 2007

2007-04-12T14:02:59Z

New page

'''ABC/HR''' is an abbreviation of ABC/Hidden Reference.

It is a method to 'score' the quality of audio encodings by comparing them alongside a reference sample. The 'hidden' comes from the fact that the listener does not know which sample -- the left or the right one -- is the reference.

The reference used usually is a sample of higher quality than the tested samples, e.g. uncompressed/losslessly compressed audio tracks, or a lossily compressed track with higher bitrate.

{{stub}}