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53 lines
2.8 KiB
HTML
53 lines
2.8 KiB
HTML
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<!doctype html public "-//w3c//dtd html 4.0 transitional//en">
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<html>
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
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<meta name="GENERATOR" content="Mozilla/4.73 [en]C-gatewaynet (Win98; U) [Netscape]">
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<meta name="Author" content="Phil Burk">
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<meta name="Description" content="Tutorial for PortAudio, a cross platform, open-source, audio I/O library.It provides a very simple API for recording and/or playing sound using a simple callback function.">
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<meta name="KeyWords" content="audio, tutorial, library, portable, open-source, DirectSound,sound, music, JSyn, synthesis,">
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<title>PortAudio Tutorial</title>
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</head>
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<body>
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<center><table COLS=1 WIDTH="100%" BGCOLOR="#FADA7A" >
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<tr>
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<td>
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<center>
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<h1>
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PortAudio Tutorial</h1></center>
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</td>
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</tr>
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</table></center>
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<h2>
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Opening a Stream using Defaults</h2>
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<blockquote>The next step is to open a stream which is similar to opening
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a file. You can specify whether you want audio input and/or output, how
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many channels, the data format, sample rate, etc. There are two calls for
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opening streams, <tt>Pa_OpenStream</tt>() and <tt>Pa_OpenDefaultStream</tt>().
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<p><tt>Pa_OpenStream()</tt> takes extra parameters which give you
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more control. You can normally just use <tt>Pa_OpenDefaultStream</tt>()
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which just calls <tt>Pa_OpenStream()</tt> <tt>with</tt> some reasonable
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default values. Let's open a stream for stereo output, using floating
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point data, at 44100 Hz.
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<blockquote>
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<pre>err = Pa_OpenDefaultStream(
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&stream, /* passes back stream pointer */
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0, /* no input channels */
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2, /* stereo output */
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paFloat32, /* 32 bit floating point output */
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44100, /* sample rate */
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256, /* frames per buffer */
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0, /* number of buffers, if zero then use default minimum */
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patestCallback, /* specify our custom callback */
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&data ); /* pass our data through to callback */</pre>
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</blockquote>
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If you want to use 16 bit integer data, pass <tt>paInt16</tt> instead of
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<tt>paFloat32</tt>.</blockquote>
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<font size=+2><a href="http://www.portaudio.com/">home</a> | <a href="pa_tutorial.html">contents</a>
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| <a href="pa_tut_init.html">previous</a> | <a href="pa_tut_run.html">next</a></font>
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</body>
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</html>
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