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	<id>https://wiki.hydrogenaudio.org/index.php?action=history&amp;feed=atom&amp;title=Filterbank</id>
	<title>Filterbank - Revision history</title>
	<link rel="self" type="application/atom+xml" href="https://wiki.hydrogenaudio.org/index.php?action=history&amp;feed=atom&amp;title=Filterbank"/>
	<link rel="alternate" type="text/html" href="https://wiki.hydrogenaudio.org/index.php?title=Filterbank&amp;action=history"/>
	<updated>2026-04-29T17:53:16Z</updated>
	<subtitle>Revision history for this page on the wiki</subtitle>
	<generator>MediaWiki 1.44.2</generator>
	<entry>
		<id>https://wiki.hydrogenaudio.org/index.php?title=Filterbank&amp;diff=23297&amp;oldid=prev</id>
		<title>Mjb: on 2nd thought, not mp3 specific enough</title>
		<link rel="alternate" type="text/html" href="https://wiki.hydrogenaudio.org/index.php?title=Filterbank&amp;diff=23297&amp;oldid=prev"/>
		<updated>2012-09-12T02:20:46Z</updated>

		<summary type="html">&lt;p&gt;on 2nd thought, not mp3 specific enough&lt;/p&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 02:20, 12 September 2012&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l2&quot;&gt;Line 2:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 2:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;[[Category:Technical]]&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;[[Category:Technical]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[Category:MP3]]&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Mjb</name></author>
	</entry>
	<entry>
		<id>https://wiki.hydrogenaudio.org/index.php?title=Filterbank&amp;diff=23283&amp;oldid=prev</id>
		<title>Mjb: related to MP3 encoding</title>
		<link rel="alternate" type="text/html" href="https://wiki.hydrogenaudio.org/index.php?title=Filterbank&amp;diff=23283&amp;oldid=prev"/>
		<updated>2012-09-12T02:05:58Z</updated>

		<summary type="html">&lt;p&gt;related to MP3 encoding&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 02:05, 12 September 2012&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l2&quot;&gt;Line 2:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 2:&lt;/td&gt;&lt;/tr&gt;
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&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;[[Category:Technical]]&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;[[Category:Technical]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[Category:MP3]]&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Mjb</name></author>
	</entry>
	<entry>
		<id>https://wiki.hydrogenaudio.org/index.php?title=Filterbank&amp;diff=13289&amp;oldid=prev</id>
		<title>Pepoluan: fix bandpass link, add link to quantization, category</title>
		<link rel="alternate" type="text/html" href="https://wiki.hydrogenaudio.org/index.php?title=Filterbank&amp;diff=13289&amp;oldid=prev"/>
		<updated>2006-09-08T22:46:56Z</updated>

		<summary type="html">&lt;p&gt;fix bandpass link, add link to quantization, category&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 22:46, 8 September 2006&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l1&quot;&gt;Line 1:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Filterbank as used in all mpeg1 layers encoding and [[MPC]] encoding (polyphase analysis filterbank), is a set of [[&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;bandpass|&lt;/del&gt;bandpass filter]], which divide the audio signal into 32 equal-width [[frequency]] [[subband]]. So, with cd-audio&#039;s 22.05kHz [[bandwidth]], the width of 1 [[subband]] is about 689Hz (32*689Hz=22.05kHz). Filterbank and its inverse are not lossless transformations. Even without quantization, the inverse transformation cannot perfectly recover the original signal. Filterbank is designed so, that the error introduced is small and inaudible.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Filterbank as used in all mpeg1 layers encoding and [[MPC]] encoding (polyphase analysis filterbank), is a set of [[bandpass filter]], which divide the audio signal into 32 equal-width [[frequency]] [[subband]]. So, with cd-audio&#039;s 22.05kHz [[bandwidth]], the width of 1 [[subband]] is about 689Hz (32*689Hz=22.05kHz). Filterbank and its inverse are not lossless transformations. Even without &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[&lt;/ins&gt;quantization&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;]]&lt;/ins&gt;, the inverse transformation cannot perfectly recover the original signal. Filterbank is designed so, that the error introduced is small and inaudible.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt; &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[Category:Technical]]&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Pepoluan</name></author>
	</entry>
	<entry>
		<id>https://wiki.hydrogenaudio.org/index.php?title=Filterbank&amp;diff=7978&amp;oldid=prev</id>
		<title>Jan at 11:49, 22 March 2005</title>
		<link rel="alternate" type="text/html" href="https://wiki.hydrogenaudio.org/index.php?title=Filterbank&amp;diff=7978&amp;oldid=prev"/>
		<updated>2005-03-22T11:49:58Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;Filterbank as used in all mpeg1 layers encoding and [[MPC]] encoding (polyphase analysis filterbank), is a set of [[bandpass|bandpass filter]], which divide the audio signal into 32 equal-width [[frequency]] [[subband]]. So, with cd-audio&amp;#039;s 22.05kHz [[bandwidth]], the width of 1 [[subband]] is about 689Hz (32*689Hz=22.05kHz). Filterbank and its inverse are not lossless transformations. Even without quantization, the inverse transformation cannot perfectly recover the original signal. Filterbank is designed so, that the error introduced is small and inaudible.&lt;/div&gt;</summary>
		<author><name>Jan</name></author>
	</entry>
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