<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>cvanal</title> <link rel="stylesheet" type="text/css" href="csound.css" /> <link rel="stylesheet" type="text/css" href="syntax-highlighting.css" /> <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /> <link rel="home" href="index.html" title="The Canonical Csound Reference Manual" /> <link rel="up" href="UtilitySoundfile.html#UtilityAnalysis" title="Analysis File Generation (ATSA, CVANAL, HETRO, LPANAL, PVANAL)" /> <link rel="prev" href="UtilityAtsa.html" title="atsa" /> <link rel="next" href="hetro.html" title="hetro" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">cvanal</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="UtilityAtsa.html">Prev</a> </td> <th width="60%" align="center">Analysis File Generation (ATSA, CVANAL, HETRO, LPANAL, PVANAL)</th> <td width="20%" align="right"> <a accesskey="n" href="hetro.html">Next</a></td> </tr> </table> <hr /> </div> <div class="refentry"> <a id="cvanal"></a> <div class="titlepage"></div> <div class="refnamediv"> <h2> <span class="refentrytitle">cvanal</span> </h2> <p>cvanal — Converts a soundfile into a single Fourier transform frame. <a id="IndexCvanal" class="indexterm"></a> </p> </div> <div class="refsect1"> <a id="idm281472811600536"></a> <h2>Description</h2> <p> Impulse Response Fourier Analysis for <a class="link" href="convolve.html" title="convolve"><em class="citetitle">convolve</em></a> operator </p> </div> <div class="refsect1"> <a id="idm281472811555448"></a> <h2>Syntax</h2> <pre class="synopsis"><span class="command"><strong>csound -U cvanal</strong></span> [flags] infilename outfilename</pre> <pre class="synopsis"><span class="command"><strong>cvanal</strong></span> [flags] infilename outfilename</pre> </div> <div class="refsect1"> <a id="idm281472811552120"></a> <h2>Initialization</h2> <p> <span class="emphasis"><em>cvanal</em></span> -- converts a soundfile into a single Fourier transform frame. The output file can be used by the <span class="emphasis"><em>convolve</em></span> operator to perform Fast Convolution between an input signal and the original impulse response. Analysis is conditioned by the flags below. A space is optional between the flag and its argument. </p> <p> <span class="emphasis"><em>-s rate</em></span> -- sampling rate of the audio input file. This will over-ride the srate of the soundfile header, which otherwise applies. If neither is present, the default is 10000. </p> <p> <span class="emphasis"><em>-c channel</em></span> -- channel number sought. If omitted, the default is to process all channels. If a value is given, only the selected channel will be processed. </p> <p> <span class="emphasis"><em>-b begin</em></span> -- beginning time (in seconds) of the audio segment to be analyzed. The default is 0.0 </p> <p> <span class="emphasis"><em>-d duration</em></span> -- duration (in seconds) of the audio segment to be analyzed. The default of 0.0 means to the end of the file. </p> <p> <span class="emphasis"><em>-X</em></span> -- write machine independent format analysis file. </p> </div> <div class="refsect1"> <a id="idm281472811545160"></a> <h2>Examples</h2> <p> </p> <pre class="programlisting"><span class="emphasis"><em>cvanal</em></span> asound cvfile</pre> <p> will analyze the soundfile "asound" to produce the file "cvfile" for the use with <a class="link" href="convolve.html" title="convolve"><em class="citetitle">convolve</em></a>. </p> <p> To use data that is not already contained in a soundfile, a soundfile converter that accepts text files may be used to create a standard audio file, e.g., the .DAT format for SOX. This is useful for implementing FIR filters. </p> <div class="refsect2"> <a id="idm281472811540664"></a> <h3>Files</h3> <p> The output file has a special <span class="emphasis"><em>convolve</em></span> header, containing details of the source audio file. The analysis data is stored as <span class="quote">“<span class="quote">float</span>”</span>, in rectangular (real/imaginary) form. </p> <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"> <table border="0" summary="Note: Note"> <tr> <td rowspan="2" align="center" valign="top" width="25"> <img alt="[Note]" src="images/note.png" /> </td> <th align="left">Note</th> </tr> <tr> <td align="left" valign="top"> <p> The analysis file is <span class="emphasis"><em>not</em></span> system independent! Ensure that the original impulse recording/data is retained. If/when required, the analysis file can be recreated. </p> </td> </tr> </table> </div> </div> </div> <div class="refsect1"> <a id="idm281472811536536"></a> <h2>Credits</h2> <p>Author: Greg Sullivan</p> <p>Based on algorithm given in <span class="emphasis"><em>Elements Of Computer Music</em></span>, by F. Richard Moore.</p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="UtilityAtsa.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="UtilitySoundfile.html#UtilityAnalysis">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="hetro.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">atsa </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> hetro</td> </tr> </table> </div> </body> </html>