https://www.bci2000.org/mediawiki/index.php?action=history&feed=atom&title=Contributions%3ADiffFilter 2026-06-25T21:05:08Z Revision history for this page on the wiki MediaWiki 1.43.6 https://www.bci2000.org/mediawiki/index.php?title=Contributions:DiffFilter&diff=6635&oldid=prev 2012-03-28T16:28:27Z

<p><span class="autocomment">Parameters</span></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 16:28, 28 March 2012</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l18">Line 18:</td> <td colspan="2" class="diff-lineno">Line 18:</td></tr> <tr><td class="diff-marker"></td><td style="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;"><div>===UnwrapDiff===</div></td><td class="diff-marker"></td><td style="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;"><div>===UnwrapDiff===</div></td></tr> <tr><td class="diff-marker"></td><td style="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;"><br></td><td class="diff-marker"></td><td style="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;"><br></td></tr> <tr><td class="diff-marker" data-marker="−"></td><td style="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;"><div>Base at which to unwrap numerical deltas.  2*pi ( = 6.283185307179586232) <del style="font-weight: bold; text-decoration: none;">is a useful </del>base <del style="font-weight: bold; text-decoration: none;">to take in order to unwrap </del>phase differences <del style="font-weight: bold; text-decoration: none;">(</del>when unwrapped at 2*pi, the first derivative of <del style="font-weight: bold; text-decoration: none;">HilbertFilter output when OutputSignal=2 </del>yields <del style="font-weight: bold; text-decoration: none;">instantaneous frequency * </del>2 * pi<del style="font-weight: bold; text-decoration: none;">)</del>.</div></td><td class="diff-marker" data-marker="+"></td><td style="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;"><div>Base at which to unwrap numerical deltas <ins style="font-weight: bold; text-decoration: none;">while computing the first derivative</ins>.  2*pi ( = 6.283185307179586232) <ins style="font-weight: bold; text-decoration: none;">would be the </ins>base <ins style="font-weight: bold; text-decoration: none;">appropriate for unwrapping </ins>phase differences<ins style="font-weight: bold; text-decoration: none;">. For example, HilbertFilter with OutputSignal=2 outputs instantaneous phase:  </ins>when unwrapped at 2*pi, the first derivative of <ins style="font-weight: bold; text-decoration: none;">this </ins>yields 2*pi <ins style="font-weight: bold; text-decoration: none;">* instantaneous frequency</ins>.</div></td></tr> <tr><td class="diff-marker"></td><td style="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;"><br></td><td class="diff-marker"></td><td style="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;"><br></td></tr> <tr><td class="diff-marker"></td><td style="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;"><div>===DivideByDeltaTime===</div></td><td class="diff-marker"></td><td style="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;"><div>===DivideByDeltaTime===</div></td></tr> <!-- diff cache key wikidb-bci_:diff:1.41:old-6627:rev-6635:php=table --> </table>

Jhill https://www.bci2000.org/mediawiki/index.php?title=Contributions:DiffFilter&diff=6627&oldid=prev 2012-03-27T01:13:14Z

<p><span class="autocomment">DivideByDeltaTime</span></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 01:13, 27 March 2012</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l22">Line 22:</td> <td colspan="2" class="diff-lineno">Line 22:</td></tr> <tr><td class="diff-marker"></td><td style="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;"><div>===DivideByDeltaTime===</div></td><td class="diff-marker"></td><td style="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;"><div>===DivideByDeltaTime===</div></td></tr> <tr><td class="diff-marker"></td><td style="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;"><br></td><td class="diff-marker"></td><td style="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;"><br></td></tr> <tr><td class="diff-marker" data-marker="−"></td><td style="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;"><div>Select whether to return raw sample-to-sample numerical deltas <del style="font-weight: bold; text-decoration: none;">in seconds</del>,  or to divide these by the time delta to approximate a true derivative.</div></td><td class="diff-marker" data-marker="+"></td><td style="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;"><div>Select whether to return raw sample-to-sample numerical deltas,  or to divide these by the time delta <ins style="font-weight: bold; text-decoration: none;">in seconds </ins>to approximate a true derivative.</div></td></tr> <tr><td class="diff-marker" data-marker="−"></td><td style="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;"><div> </div></td><td colspan="2" class="diff-side-added"></td></tr> <tr><td class="diff-marker"></td><td style="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;"><br></td><td class="diff-marker"></td><td style="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;"><br></td></tr> <tr><td class="diff-marker"></td><td style="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;"><div>==States==</div></td><td class="diff-marker"></td><td style="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;"><div>==States==</div></td></tr> <!-- diff cache key wikidb-bci_:diff:1.41:old-6625:rev-6627:php=table --> </table>

Jhill https://www.bci2000.org/mediawiki/index.php?title=Contributions:DiffFilter&diff=6625&oldid=prev 2012-03-27T00:31:51Z

<p></p> <p><b>New page</b></p><div>==Synopsis==<br /> <br /> Take the derivative of a continuous time-series input wrt. time<br /> <br /> ==Location==<br /> http://{{SERVERNAME}}/svn/trunk/src/contrib/SignalProcessing/HilbertSignalProcessing/DiffFilter.cpp<br /> <br /> ==Versioning==<br /> ===Authors===<br /> Jeremy Hill<br /> <br /> ==Parameters==<br /> <br /> ===DiffOrder===<br /> <br /> 0 = disable; 1 = first derivative; 2 = second derivative; etc<br /> <br /> ===UnwrapDiff===<br /> <br /> Base at which to unwrap numerical deltas. 2*pi ( = 6.283185307179586232) is a useful base to take in order to unwrap phase differences (when unwrapped at 2*pi, the first derivative of HilbertFilter output when OutputSignal=2 yields instantaneous frequency * 2 * pi).<br /> <br /> ===DivideByDeltaTime===<br /> <br /> Select whether to return raw sample-to-sample numerical deltas in seconds, or to divide these by the time delta to approximate a true derivative.<br /> <br /> <br /> ==States==<br /> None.<br /> <br /> ==See also==<br /> [[User Reference:Filters]], [[Contributions:SignalProcessing]], [[Contributions:HilbertSignalProcessing]]<br /> <br /> [[Category:Contributions]][[Category:Signal Processing]]</div>

Jhill