Chris@41: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> Chris@41: <HTML> Chris@41: Chris@41: <HEAD> Chris@41: <TITLE> Chris@41: Secret Rabbit Code (aka libsamplerate) Chris@41: </TITLE> Chris@41: <META NAME="Author" CONTENT="Erik de Castro Lopo (erikd AT mega-nerd DOT com)"> Chris@41: <META NAME="Version" CONTENT="libsamplerate-0.1.8"> Chris@41: <META NAME="Description" CONTENT="The Secret Rabbit Code Home Page"> Chris@41: <META NAME="Keywords" CONTENT="libsamplerate sound resample audio dsp Linux"> Chris@41: <LINK REL=StyleSheet HREF="SRC.css" TYPE="text/css" MEDIA="all"> Chris@41: </HEAD> Chris@41: Chris@41: <BODY TEXT="#FFFFFF" BGCOLOR="#000000" LINK="#FB1465" VLINK="#FB1465" ALINK="#FB1465"> Chris@41: <!-- pepper --> Chris@41: <CENTER> Chris@41: <IMG SRC="SRC.png" HEIGHT=100 WIDTH=760 ALT="SRC.png"> Chris@41: </CENTER> Chris@41: <!-- pepper --> Chris@41: <BR> Chris@41: <!-- pepper --> Chris@41: <TABLE ALIGN="center" WIDTH="98%"> Chris@41: <TR> Chris@41: <TD VALIGN="top"> Chris@41: <BR> Chris@41: <DIV CLASS="nav"> Chris@41: <BR> Chris@41: <A HREF="index.html">Home</A><BR> Chris@41: <A HREF="license.html">License</A><BR> Chris@41: <A HREF="history.html">History</A><BR> Chris@41: <A HREF="download.html">Download</A><BR> Chris@41: <A HREF="quality.html">Quality</A><BR> Chris@41: <A HREF="api.html">API</A><BR> Chris@41: <A HREF="bugs.html">Bug Reporting</A><BR> Chris@41: <A HREF="win32.html">On Win32</A><BR> Chris@41: <A HREF="faq.html">FAQ</A><BR> Chris@41: <A HREF="lists.html">Mailing Lists</A><BR> Chris@41: <A HREF="ChangeLog">ChangeLog</A><BR> Chris@41: <BR> Chris@41: <DIV CLASS="block"> Chris@41: Author :<BR>Erik de Castro Lopo Chris@41: <!-- pepper --> Chris@41: <BR><BR> Chris@41: <!-- pepper --> Chris@41: Chris@41: </DIV> Chris@41: <IMG SRC= Chris@41: "/cgi-bin/Count.cgi?ft=6|frgb=55;55;55|tr=0|md=6|dd=B|st=1|sh=1|df=src.dat" Chris@41: HEIGHT=30 WIDTH=100 ALT="counter.gif"> Chris@41: </DIV> Chris@41: Chris@41: </TD> Chris@41: <!-- pepper --> Chris@41: <!-- ######################################################################## --> Chris@41: <!-- pepper --> Chris@41: <TD VALIGN="top"> Chris@41: <DIV CLASS="block"> Chris@41: <BR> Chris@41: Chris@41: <TABLE ALIGN="center" WIDTH="80%"> Chris@41: <TR><TD> Chris@41: <P> Chris@41: <I> Chris@41: "Choosing a sample rate coverter wasn't easy. We ran numerous tests with Chris@41: Secret Rabbit Code and other sample rate converters, then compared them all. Chris@41: In the end, SRC outperformed the others, including some extremely well known Chris@41: and popular software. We had one issue with SRC, but after emailing Erik, he Chris@41: got back to us immediately with an answer. Choosing SRC was a no brainer." Chris@41: </I><BR> Chris@41: Ryan Smith, International Marketing Manager, <BR> Chris@41: <A HREF="http://emersys.co.kr/">Emersys Corp.</A>, South Korea.<BR> Chris@41: Product : <A HREF="http://maven3d.com">Maven3D</A> Chris@41: Chris@41: </P> Chris@41: </TD></TR> Chris@41: </TABLE> Chris@41: <P> Chris@41: <B>S</B>ecret <B>R</B>abbit <B>C</B>ode (aka libsamplerate) is a Chris@41: <B>S</B>ample <B>R</B>ate <B>C</B>onverter for audio. Chris@41: One example of where such a thing would be useful is converting audio Chris@41: from the CD sample rate of 44.1kHz to the 48kHz sample rate used by Chris@41: DAT players. Chris@41: </P> Chris@41: <!-- pepper --> Chris@41: <P> Chris@41: <B>SRC</B> is capable of arbitrary and time varying conversions ; from Chris@41: downsampling by a factor of 256 to upsampling by the same factor. Chris@41: Arbitrary in this case means that the ratio of input and output Chris@41: sample rates can be an irrational number. Chris@41: The conversion ratio can also vary with time for speeding up and slowing Chris@41: down effects. Chris@41: </P> Chris@41: <!-- pepper --> Chris@41: <P> Chris@41: <B>SRC</B> provides a small set of converters to allow quality to Chris@41: be traded off against computation cost. Chris@41: The current best converter provides a signal-to-noise ratio of 145dB Chris@41: with -3dB passband extending from DC to 96% of the theoretical Chris@41: best bandwidth for a given pair of input and output sample rates. Chris@41: </P> Chris@41: <!-- pepper --> Chris@41: <P> Chris@41: Since the library has few dependencies beyond that provided by the Chris@41: standard C library, it should compile and work on just about any Chris@41: operating system. Chris@41: It is known to work on Linux, MacOSX, Chris@41: <A HREF="win32.html">Win32</A> Chris@41: and Solaris. Chris@41: With some relatively minor hacking it should also be relatively easy Chris@41: to port it to embedded systems and digital signal processors. Chris@41: </P> Chris@41: <!-- pepper --> Chris@41: <P> Chris@41: In addition, the library comes with a comprehensive test suite which Chris@41: can validate the performance of the library on new platforms. Chris@41: </P> Chris@41: Chris@41: <!-- pepper --> Chris@41: <!-- <A HREF="mailto:aldel0305@mega-nerd.com">For the spam bots</A> --> Chris@41: <!-- pepper --> Chris@41: Chris@41: </DIV> Chris@41: </TD></TR> Chris@41: </TABLE> Chris@41: Chris@41: </BODY> Chris@41: </HTML> Chris@41: