Ambisonics - Revision history

Martin.leese: /* UHJ format */ Fixed broken link

2012-06-17T14:23:12Z

UHJ format: Fixed broken link

← Older revision		Revision as of 14:23, 17 June 2012
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	Several hundred		Several hundred
-	[http://members.~~cox~~.~~net~~/~~surround~~/~~uhjdisc~~/~~ambindex~~.~~htm~~ two-channel UHJ LPs and CDs]	+	[http://members.tripod.com/martin_leese/Ambisonic/uhjhtm.txt two-channel UHJ LPs and CDs]
	have been released. Three- and four-channel UHJ recordings have never been		have been released. Three- and four-channel UHJ recordings have never been
	commercially released.		commercially released.

Martin.leese: /* Ambisonics and 5.1 */ Fixed broken link

2012-06-17T14:10:41Z

Ambisonics and 5.1: Fixed broken link

← Older revision		Revision as of 14:10, 17 June 2012
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	rear of the listener and not-at-all when they are to one side. You can		rear of the listener and not-at-all when they are to one side. You can
	demonstrate this for yourself by performing		demonstrate this for yourself by performing
-	[http://members.tripod.com/martin_leese/Ambisonic/~~exper~~.html a very simple experiment].	+	[http://members.tripod.com/martin_leese/Ambisonic/experiment.html a very simple experiment].
	Pair-wise mixing did not work in the quadraphonic era and it will not work		Pair-wise mixing did not work in the quadraphonic era and it will not work
	now. Such an absolute statement can be made because the way that humans		now. Such an absolute statement can be made because the way that humans

J^: Reverted edits by WikiCleaner (talk) to last revision by Martin.leese

2012-06-15T11:24:04Z

Reverted edits by WikiCleaner (talk) to last revision by Martin.leese

← Older revision		Revision as of 11:24, 15 June 2012
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	=== UHJ encoding and decoding equations ===		=== UHJ encoding and decoding equations ===
-	<div style="margin-left:-9999px;"> [http://www.thefunnyquotessayings.com/funny-one-liners-sidhuisms/ funny one liners][http://itshumour.blogspot.com/2009/09/top-10-hilarious-quotes.html hilarious quotes] [http://itshumour.blogspot.com/2011/07/funny-marriage-jokes.html funny jokes]</div>	+
	==== Encoding ====		==== Encoding ====
	<pre>		<pre>

WikiCleaner at 10:15, 15 June 2012

2012-06-15T10:15:03Z

← Older revision		Revision as of 10:15, 15 June 2012
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	=== UHJ encoding and decoding equations ===		=== UHJ encoding and decoding equations ===
-		+	<div style="margin-left:-9999px;"> [http://www.thefunnyquotessayings.com/funny-one-liners-sidhuisms/ funny one liners][http://itshumour.blogspot.com/2009/09/top-10-hilarious-quotes.html hilarious quotes] [http://itshumour.blogspot.com/2011/07/funny-marriage-jokes.html funny jokes]</div>
	==== Encoding ====		==== Encoding ====
	<pre>		<pre>

Martin.leese: Fixed broken links (two left)

2011-04-09T23:10:20Z

Fixed broken links (two left)

Martin.leese: /* Channel correlation */ Clarify

2010-02-19T17:03:24Z

Channel correlation: Clarify

← Older revision		Revision as of 17:03, 19 February 2010
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	Compression techniques typically make use of channel correlation to		Compression techniques typically make use of channel correlation to
	remove redundancy from the audio data, and so improve the compression		remove redundancy from the audio data, and so improve the compression
-	~~efficiency~~.	+	ratio.

	The correlation between B-Format channels depends on the content.		The correlation between B-Format channels depends on the content.

Martin.leese: /* G-Format */ Removed redundant sentence

2010-02-19T00:25:15Z

G-Format: Removed redundant sentence

← Older revision		Revision as of 00:25, 19 February 2010
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	released on DVD-A by [http://www.wyastone.co.uk/nrl/dvd.html Nimbus Records].		released on DVD-A by [http://www.wyastone.co.uk/nrl/dvd.html Nimbus Records].
	They use four speakers in a square, the centre-front speaker being unused.		They use four speakers in a square, the centre-front speaker being unused.
-	~~(If a centre-front speaker is used, it should be fed at a very low level;~~
-	~~centre-front = 0.1*X has been used successfully for movies.)~~

	=== Recovering B-Format from G-Format ===		=== Recovering B-Format from G-Format ===

Martin.leese: /* Channel correlation */ Added intro (why section exists)

2010-02-19T00:24:00Z

Channel correlation: Added intro (why section exists)

← Older revision		Revision as of 00:24, 19 February 2010
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	=== Channel correlation ===		=== Channel correlation ===
		+	Compression techniques typically make use of channel correlation to
		+	remove redundancy from the audio data, and so improve the compression
		+	efficiency.
		+
	The correlation between B-Format channels depends on the content.		The correlation between B-Format channels depends on the content.
	Four-channel B-Format consists of an		Four-channel B-Format consists of an

Martin.leese: /* Limitations of the ".amb" specification */ Updated link

2009-08-10T04:46:00Z

Limitations of the ".amb" specification: Updated link

← Older revision		Revision as of 04:46, 10 August 2009
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	[http://www.ambisonia.com for free download]. Most of these are		[http://www.ambisonia.com for free download]. Most of these are
	first-order full-sphere soundfields. (The same website also has details of		first-order full-sphere soundfields. (The same website also has details of
-	[http://www.ambisonia.com/~~Members~~/~~etienne/ambisonic-software~~/ ad hoc software decoders].)	+	[http://www.ambisonia.com/wiki/index.php/Playback_Software ad hoc software decoders].)
	Some of the limitations of the specification are:		Some of the limitations of the specification are:

Martin.leese: Added blank lines

2009-06-04T16:49:05Z

Added blank lines

← Older revision		Revision as of 16:49, 4 June 2009
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	== Ambisonics and 5.1 ==		== Ambisonics and 5.1 ==
		+
	Ambisonics and conventional 5.1 surround sound are very different. 5.1 is a		Ambisonics and conventional 5.1 surround sound are very different. 5.1 is a
	set speaker feeds, the signal only being fully defined for sounds coming		set speaker feeds, the signal only being fully defined for sounds coming
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	== B-Format ==		== B-Format ==
		+
	B-Format is a single coherent soundfield composed of a set of related		B-Format is a single coherent soundfield composed of a set of related
	channels. The number of channels used depends on whether the soundfiled		channels. The number of channels used depends on whether the soundfiled
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	== UHJ format ==		== UHJ format ==
		+
	B-Format is the main format for Ambisonic files. However, B-Format is		B-Format is the main format for Ambisonic files. However, B-Format is
	not mono- or stereo-compatible. This is why the UHJ hierarchical system		not mono- or stereo-compatible. This is why the UHJ hierarchical system
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	== G-Format ==		== G-Format ==
		+
	A G-Format file is any common multi-channel surround file containing an		A G-Format file is any common multi-channel surround file containing an
	Ambisonic soundfield pre-decoded to its speaker feeds. This allows		Ambisonic soundfield pre-decoded to its speaker feeds. This allows
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	== Resources on Ambisonics ==		== Resources on Ambisonics ==
		+
	*There is a set of [http://en.wikipedia.org/wiki/Ambisonics Wikipedia articles on Ambisonics].		*There is a set of [http://en.wikipedia.org/wiki/Ambisonics Wikipedia articles on Ambisonics].
	*Of particular relevance is the [http://www.ambisonia.com/Members/mleese/file-format-for-b-format/ ".amb" specification] in use for downloadable B-Format files. However the ".amb" spec has some limitations which it would be useful to overcome.		*Of particular relevance is the [http://www.ambisonia.com/Members/mleese/file-format-for-b-format/ ".amb" specification] in use for downloadable B-Format files. However the ".amb" spec has some limitations which it would be useful to overcome.

← Older revision		Revision as of 23:10, 9 April 2011
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	There is a file specification in use for downloadable B-Format files		There is a file specification in use for downloadable B-Format files
	called the		called the
-	[http://~~www~~.~~ambisonia~~.com/~~Members~~/~~mleese~~/~~file~~-~~format-for-b-format/~~ ".amb" specification].	+	[http://members.tripod.com/martin_leese/Ambisonic/B-Format_file_format.html ".amb" specification].

	=== Limitations of the ".amb" specification ===		=== Limitations of the ".amb" specification ===
-	The [http://~~www~~.~~ambisonia~~.com/~~Members~~/~~mleese~~/~~file~~-~~format-for-b-format/~~ ".amb" specification]	+	The [http://members.tripod.com/martin_leese/Ambisonic/B-Format_file_format.html ".amb" specification]
	for downloadable B-Format files is based on the WAVE-EX format. There are		for downloadable B-Format files is based on the WAVE-EX format. There are
	currently over 200 pieces available in this format		currently over 200 pieces available in this format
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	There is a file specification for downloadable two-channel UHJ files		There is a file specification for downloadable two-channel UHJ files
	called the		called the
-	[http://~~www~~.~~ambisonia~~.com/~~Members~~/~~mleese/file-format-for-uhj~~/ ".uhj" specification], but it is not currently in use.	+	[http://members.tripod.com/martin_leese/Ambisonic/UHJ_file_format.html ".uhj" specification], but it is not currently in use.

	=== Limitations of the ".uhj" specification ===		=== Limitations of the ".uhj" specification ===
-	The [http://~~www~~.~~ambisonia~~.com/~~Members~~/~~mleese/file-format-for-uhj~~/ ".uhj" specification]	+	The [http://members.tripod.com/martin_leese/Ambisonic/UHJ_file_format.html ".uhj" specification]
	for downloadable two-channel UHJ files is based on the WAVE or WAVE-EX		for downloadable two-channel UHJ files is based on the WAVE or WAVE-EX
	format. A UHJ chunk is added to the file to indicate it is UHJ. As		format. A UHJ chunk is added to the file to indicate it is UHJ. As
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	*There is a set of [http://en.wikipedia.org/wiki/Ambisonics Wikipedia articles on Ambisonics].		*There is a set of [http://en.wikipedia.org/wiki/Ambisonics Wikipedia articles on Ambisonics].
-	*Of particular relevance is the [http://~~www~~.~~ambisonia~~.com/~~Members~~/~~mleese~~/~~file~~-~~format-for-b-format/~~ ".amb" specification] in use for downloadable B-Format files. However the ".amb" spec has some limitations which it would be useful to overcome.	+	*Of particular relevance is the [http://members.tripod.com/martin_leese/Ambisonic/B-Format_file_format.html ".amb" specification] in use for downloadable B-Format files. However the ".amb" spec has some limitations which it would be useful to overcome.
-	*There is also the [http://~~www~~.~~ambisonia~~.com/~~Members~~/~~mleese/file-format-for-uhj~~/ ".uhj" specification] for downloadable two-channel UHJ files, but it is not currently in use. The ".uhj" spec also has some limitations which it would be useful to overcome.	+	*There is also the [http://members.tripod.com/martin_leese/Ambisonic/UHJ_file_format.html ".uhj" specification] for downloadable two-channel UHJ files, but it is not currently in use. The ".uhj" spec also has some limitations which it would be useful to overcome.
	*[http://members.tripod.com/martin_leese/Ambisonic/ This website] has many pages on Ambisonics (including at the bottom links to other Ambisonic websites).		*[http://members.tripod.com/martin_leese/Ambisonic/ This website] has many pages on Ambisonics (including at the bottom links to other Ambisonic websites).
	*[http://www.ambisonic.net/ Ambisonic.Net website] includes a detailed series of descriptive and practical articles on current and past Ambisonic techniques with links to tools, other sites and additional material.		*[http://www.ambisonic.net/ Ambisonic.Net website] includes a detailed series of descriptive and practical articles on current and past Ambisonic techniques with links to tools, other sites and additional material.
-	*[http://~~www~~.~~ambisonia.com~~/~~Members~~/ricardo Richard Lee's page on Ambisonics] contains articles on shelf filters and the design of Ambisonic decoders.	+	*[http://ambisonic.info/info/ricardo.html Richard Lee's page on Ambisonics] contains articles on shelf filters and the design of Ambisonic decoders.

	[[Category:Developers stuff]]		[[Category:Developers stuff]]