mirror of
https://github.com/cookiengineer/audacity
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131 lines
3.9 KiB
HTML
131 lines
3.9 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML>
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<TITLE>
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Secret Rabbit Code (aka libsamplerate)
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</TITLE>
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<META NAME="Author" CONTENT="Erik de Castro Lopo (erikd AT mega-nerd DOT com)">
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<META NAME="Version" CONTENT="libsamplerate-0.1.7">
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<META NAME="Description" CONTENT="The Secret Rabbit Code Home Page">
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<META NAME="Keywords" CONTENT="libsamplerate sound resample audio dsp Linux">
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<LINK REL=StyleSheet HREF="SRC.css" TYPE="text/css" MEDIA="all">
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</HEAD>
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<BODY TEXT="#FFFFFF" BGCOLOR="#000000" LINK="#FB1465" VLINK="#FB1465" ALINK="#FB1465">
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<CENTER>
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<IMG SRC="SRC.png" HEIGHT=100 WIDTH=760 ALT="SRC.png">
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</CENTER>
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<BR>
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<TABLE ALIGN="center" WIDTH="98%">
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<TR>
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<TD VALIGN="top">
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<BR>
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<DIV CLASS="nav">
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<BR>
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<A HREF="index.html">Home</A><BR>
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<A HREF="license.html">License</A><BR>
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<A HREF="history.html">History</A><BR>
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<A HREF="download.html">Download</A><BR>
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<A HREF="quality.html">Quality</A><BR>
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<A HREF="api.html">API</A><BR>
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<A HREF="bugs.html">Bug Reporting</A><BR>
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<A HREF="win32.html">On Win32</A><BR>
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<A HREF="faq.html">FAQ</A><BR>
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<A HREF="lists.html">Mailing Lists</A><BR>
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<A HREF="ChangeLog">ChangeLog</A><BR>
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<A HREF="fb2k.html">Foobar 2k</A><BR>
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<BR>
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<DIV CLASS="block">
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Author :<BR>Erik de Castro Lopo
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<BR><BR>
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<IMG SRC=
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"/cgi-bin/Count.cgi?ft=6|frgb=55;55;55|tr=0|md=6|dd=B|st=1|sh=1|df=src.dat"
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HEIGHT=30 WIDTH=100 ALT="counter.gif">
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</DIV>
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<TD VALIGN="top">
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<DIV CLASS="block">
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<BR>
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<TABLE ALIGN="center" WIDTH="80%">
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<TR><TD>
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<P>
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<I>
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"Choosing a sample rate coverter wasn't easy. We ran numerous tests with
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Secret Rabbit Code and other sample rate converters, then compared them all.
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In the end, SRC outperformed the others, including some extremely well known
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and popular software. We had one issue with SRC, but after emailing Erik, he
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got back to us immediately with an answer. Choosing SRC was a no brainer."
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</I><BR>
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Ryan Smith, International Marketing Manager, <BR>
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<A HREF="http://emersys.co.kr/">Emersys Corp.</A>, South Korea.<BR>
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Product : <A HREF="http://maven3d.com">Maven3D</A>
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</P>
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</TD></TR>
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</TABLE>
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<P>
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<B>S</B>ecret <B>R</B>abbit <B>C</B>ode (aka libsamplerate) is a
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<B>S</B>ample <B>R</B>ate <B>C</B>onverter for audio.
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One example of where such a thing would be useful is converting audio
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from the CD sample rate of 44.1kHz to the 48kHz sample rate used by
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DAT players.
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</P>
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<P>
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<B>SRC</B> is capable of arbitrary and time varying conversions ; from
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downsampling by a factor of 256 to upsampling by the same factor.
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Arbitrary in this case means that the ratio of input and output
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sample rates can be an irrational number.
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The conversion ratio can also vary with time for speeding up and slowing
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down effects.
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</P>
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<P>
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<B>SRC</B> provides a small set of converters to allow quality to
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be traded off against computation cost.
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The current best converter provides a signal-to-noise ratio of 145dB
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with -3dB passband extending from DC to 96% of the theoretical
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best bandwidth for a given pair of input and output sample rates.
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</P>
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<P>
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Since the library has few dependencies beyond that provided by the
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standard C library, it should compile and work on just about any
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operating system.
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It is known to work on Linux, MacOSX,
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<A HREF="win32.html">Win32</A>
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and Solaris.
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With some relatively minor hacking it should also be relatively easy
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to port it to embedded systems and digital signal processors.
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</P>
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<P>
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In addition, the library comes with a comprehensive test suite which
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can validate the performance of the library on new platforms.
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</P>
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<!-- <A HREF="mailto:aldel0305@mega-nerd.com">For the spam bots</A> -->
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</HTML>
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