| Emeric Vigier | eebea67 | 2012-08-06 17:36:30 -0400 | [diff] [blame] | 1 | <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> |
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| 6 | Secret Rabbit Code (aka libsamplerate) |
| 7 | </TITLE> |
| 8 | <META NAME="Author" CONTENT="Erik de Castro Lopo (erikd AT mega-nerd DOT com)"> |
| 9 | <META NAME="Version" CONTENT="libsamplerate-0.1.8"> |
| 10 | <META NAME="Description" CONTENT="The Secret Rabbit Code Home Page"> |
| 11 | <META NAME="Keywords" CONTENT="libsamplerate sound resample audio dsp Linux"> |
| 12 | <LINK REL=StyleSheet HREF="SRC.css" TYPE="text/css" MEDIA="all"> |
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| 28 | <BR> |
| 29 | <A HREF="index.html">Home</A><BR> |
| 30 | <A HREF="license.html">License</A><BR> |
| 31 | <A HREF="history.html">History</A><BR> |
| 32 | <A HREF="download.html">Download</A><BR> |
| 33 | <A HREF="quality.html">Quality</A><BR> |
| 34 | <A HREF="api.html">API</A><BR> |
| 35 | <A HREF="bugs.html">Bug Reporting</A><BR> |
| 36 | <A HREF="win32.html">On Win32</A><BR> |
| 37 | <A HREF="faq.html">FAQ</A><BR> |
| 38 | <A HREF="lists.html">Mailing Lists</A><BR> |
| 39 | <A HREF="ChangeLog">ChangeLog</A><BR> |
| 40 | <A HREF="fb2k.html">Foobar 2k</A><BR> |
| 41 | <BR> |
| 42 | <DIV CLASS="block"> |
| 43 | Author :<BR>Erik de Castro Lopo |
| 44 | <!-- pepper --> |
| 45 | <BR><BR> |
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| 47 | |
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| 63 | <TR><TD> |
| 64 | <P> |
| 65 | <I> |
| 66 | "Choosing a sample rate coverter wasn't easy. We ran numerous tests with |
| 67 | Secret Rabbit Code and other sample rate converters, then compared them all. |
| 68 | In the end, SRC outperformed the others, including some extremely well known |
| 69 | and popular software. We had one issue with SRC, but after emailing Erik, he |
| 70 | got back to us immediately with an answer. Choosing SRC was a no brainer." |
| 71 | </I><BR> |
| 72 | Ryan Smith, International Marketing Manager, <BR> |
| 73 | <A HREF="http://emersys.co.kr/">Emersys Corp.</A>, South Korea.<BR> |
| 74 | Product : <A HREF="http://maven3d.com">Maven3D</A> |
| 75 | |
| 76 | </P> |
| 77 | </TD></TR> |
| 78 | </TABLE> |
| 79 | <P> |
| 80 | <B>S</B>ecret <B>R</B>abbit <B>C</B>ode (aka libsamplerate) is a |
| 81 | <B>S</B>ample <B>R</B>ate <B>C</B>onverter for audio. |
| 82 | One example of where such a thing would be useful is converting audio |
| 83 | from the CD sample rate of 44.1kHz to the 48kHz sample rate used by |
| 84 | DAT players. |
| 85 | </P> |
| 86 | <!-- pepper --> |
| 87 | <P> |
| 88 | <B>SRC</B> is capable of arbitrary and time varying conversions ; from |
| 89 | downsampling by a factor of 256 to upsampling by the same factor. |
| 90 | Arbitrary in this case means that the ratio of input and output |
| 91 | sample rates can be an irrational number. |
| 92 | The conversion ratio can also vary with time for speeding up and slowing |
| 93 | down effects. |
| 94 | </P> |
| 95 | <!-- pepper --> |
| 96 | <P> |
| 97 | <B>SRC</B> provides a small set of converters to allow quality to |
| 98 | be traded off against computation cost. |
| 99 | The current best converter provides a signal-to-noise ratio of 145dB |
| 100 | with -3dB passband extending from DC to 96% of the theoretical |
| 101 | best bandwidth for a given pair of input and output sample rates. |
| 102 | </P> |
| 103 | <!-- pepper --> |
| 104 | <P> |
| 105 | Since the library has few dependencies beyond that provided by the |
| 106 | standard C library, it should compile and work on just about any |
| 107 | operating system. |
| 108 | It is known to work on Linux, MacOSX, |
| 109 | <A HREF="win32.html">Win32</A> |
| 110 | and Solaris. |
| 111 | With some relatively minor hacking it should also be relatively easy |
| 112 | to port it to embedded systems and digital signal processors. |
| 113 | </P> |
| 114 | <!-- pepper --> |
| 115 | <P> |
| 116 | In addition, the library comes with a comprehensive test suite which |
| 117 | can validate the performance of the library on new platforms. |
| 118 | </P> |
| 119 | |
| 120 | <!-- pepper --> |
| 121 | <!-- <A HREF="mailto:aldel0305@mega-nerd.com">For the spam bots</A> --> |
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