<?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>srconv</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="UtilityConversion.html" title="File Conversion (HET_IMPORT, HET_EXPORT, PVLOOK, PV_EXPORT, PV_IMPORT, SDIF2AD, SRCONV)" /> <link rel="prev" href="sdif2ad.html" title="sdif2ad" /> <link rel="next" href="src_conv.html" title="src_conv" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">srconv</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="sdif2ad.html">Prev</a> </td> <th width="60%" align="center">File Conversion (HET_IMPORT, HET_EXPORT, PVLOOK, PV_EXPORT, PV_IMPORT, SDIF2AD, SRCONV)</th> <td width="20%" align="right"> <a accesskey="n" href="src_conv.html">Next</a></td> </tr> </table> <hr /> </div> <div class="refentry"> <a id="srconv"></a> <div class="titlepage"></div> <div class="refnamediv"> <h2> <span class="refentrytitle">srconv</span> </h2> <p>srconv — Converts the sample rate of an audio file. <a id="IndexSrconv" class="indexterm"></a> </p> </div> <div class="refsect1"> <a id="idm281472810626504"></a> <h2>Description</h2> <p> Converts the sample rate of an audio file at sample rate Rin to a sample rate of Rout. Optionally the ratio (Rin / Rout) may be linearly time-varying according to a set of (time, ratio) pairs in an auxiliary file. </p> <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"> <table border="0" summary="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">This utility is suspect. Better is to use libsamplerate. srconv will be removed or replaced soon.</td> </tr> </table> </div> <p> </p> </div> <div class="refsect1"> <a id="idm281472810621704"></a> <h2>Syntax</h2> <pre class="synopsis"><span class="command"><strong>srconv</strong></span> [flags] infile</pre> </div> <div class="refsect1"> <a id="idm281472810619656"></a> <h2>Initialization</h2> <p> Flags: </p> <div class="itemizedlist"> <ul class="itemizedlist" style="list-style-type: disc; "> <li class="listitem"> <p>-<span class="emphasis"><em>P num</em></span> = pitch transposition ratio (srate / r) [don't specify both P and r]</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>Q num</em></span> =quality factor (1, 2, 3, or 4: default = 2)</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>i filnam</em></span> = auxiliary breakpoints file (no breakpoint by default. i.e. No ratio change) </p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>r num</em></span> = output sample rate (must be specified)</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>o fnam</em></span> = sound output filename</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>A</em></span> = create an AIFF format output soundfile</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>J</em></span> = create an IRCAM format output soundfile</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>W</em></span> = create a WAV format output soundfile</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>h</em></span> = no header on output soundfile</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>c</em></span> = 8-bit signed_char sound samples</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>a</em></span> = alaw sound samples</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>8</em></span> = 8-bit unsigned_char sound samples</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>u</em></span> = ulaw sound samples</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>s</em></span> = short_int sound samples</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>l</em></span> = long_int sound samples</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>f</em></span> = float sound samples</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>r N</em></span> = orchestra srate override</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>K</em></span> = Do not generate PEAK chunks</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>R</em></span> = continually rewrite header while writing soundfile (WAV/AIFF)</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>H#</em></span> = print a heartbeat style 1, 2 or 3 at each soundfile write</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>N</em></span> = notify (ring the bell) when score or miditrack is done</p> </li> <li class="listitem"> <p>-<span class="emphasis"><em>- fnam</em></span> = log output to file</p> </li> </ul> </div> <p> </p> <p> This program performs arbitrary sample-rate conversion with high fidelity. The method is to step through the input at the desired sampling increment, and to compute the output points as appropriately weighted averages of the surrounding input points. There are two cases to consider: </p> <div class="orderedlist"> <ol class="orderedlist" type="1"> <li class="listitem"> <p>sample rates are in a small-integer ratio - weights are obtained from table.</p> </li> <li class="listitem"> <p>sample rates are in a large-integer ratio - weights are linearly interpolated from table.</p> </li> </ol> </div> <p> </p> <p> Calculate increment: if decimating, then window is impulse response of low-pass filter with cutoff frequency at half of output sample rate; if interpolating, then window is impulse response of lowpass filter with cutoff frequency at half of input sample rate. </p> </div> <div class="refsect1"> <a id="idm281472810530840"></a> <h2>Credits</h2> <p>Author: Mark Dolson</p> <p>August 26, 1989</p> <p>Author: John ffitch</p> <p>December 30, 2000</p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="sdif2ad.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="UtilityConversion.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="src_conv.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">sdif2ad </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> src_conv</td> </tr> </table> </div> </body> </html>