annotate src/libvorbis-1.3.3/doc/vorbisfile/initialization.html @ 1:05aa0afa9217

Bring in flac, ogg, vorbis
author Chris Cannam
date Tue, 19 Mar 2013 17:37:49 +0000
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Chris@1 1 <html>
Chris@1 2
Chris@1 3 <head>
Chris@1 4 <title>Vorbisfile - Setup/Teardown</title>
Chris@1 5 <link rel=stylesheet href="style.css" type="text/css">
Chris@1 6 </head>
Chris@1 7
Chris@1 8 <body bgcolor=white text=black link="#5555ff" alink="#5555ff" vlink="#5555ff">
Chris@1 9 <table border=0 width=100%>
Chris@1 10 <tr>
Chris@1 11 <td><p class=tiny>Vorbisfile documentation</p></td>
Chris@1 12 <td align=right><p class=tiny>vorbisfile version 1.3.2 - 20101101</p></td>
Chris@1 13 </tr>
Chris@1 14 </table>
Chris@1 15
Chris@1 16 <H1>Setup/Teardown</h1> <p>In order to decode audio using
Chris@1 17 libvorbisfile, a bitstream containing Vorbis audio must be properly
Chris@1 18 initialized before decoding and cleared when decoding is finished.
Chris@1 19 The simplest possible case is to use <a
Chris@1 20 href="ov_fopen.html">ov_fopen()</a> to open the file for access, check
Chris@1 21 it for Vorbis content, and prepare it for playback. A successful <a
Chris@1 22 href="../libvorbis/return.html">return code</a> from <a
Chris@1 23 href="ov_fopen.html">ov_fopen()</a> indicates the file is ready for use.
Chris@1 24 Once the file is no longer needed, <a
Chris@1 25 href="ov_clear.html">ov_clear()</a> is used to close the file and
Chris@1 26 deallocate decoding resources.<p>
Chris@1 27
Chris@1 28 On systems other than Windows<a href="ov_open.html#winfoot">[a]</a>, an
Chris@1 29 application may also open a file itself using <tt>fopen()</tt>, then pass the
Chris@1 30 <tt>FILE *</tt> to libvorbisfile using <a
Chris@1 31 href="ov_open.html">ov_open()</a>. </b>Do not</b> call
Chris@1 32 <tt>fclose()</tt> on a file handle successfully submitted to <a
Chris@1 33 href="ov_open.html">ov_open()</a>; libvorbisfile does this in the <a
Chris@1 34 href="ov_clear.html">ov_clear()</a> call.<p>
Chris@1 35
Chris@1 36 An application that requires more setup flexibility may open a data
Chris@1 37 stream using <a href="ov_open_callbacks.html">ov_open_callbacks()</a>
Chris@1 38 to change default libvorbis behavior or specify non-stdio data access
Chris@1 39 mechanisms.<p>
Chris@1 40
Chris@1 41 <p>
Chris@1 42 All libvorbisfile initialization and deallocation routines are declared in "vorbis/vorbisfile.h".
Chris@1 43 <p>
Chris@1 44
Chris@1 45 <table border=1 color=black width=50% cellspacing=0 cellpadding=7>
Chris@1 46 <tr bgcolor=#cccccc>
Chris@1 47 <td><b>function</b></td>
Chris@1 48 <td><b>purpose</b></td>
Chris@1 49 </tr>
Chris@1 50 <tr valign=top>
Chris@1 51 <td><a href="ov_fopen.html">ov_fopen</a></td>
Chris@1 52 <td>Opens a file and initializes the Ogg Vorbis bitstream with default values. This must be called before other functions in the library may be
Chris@1 53 used.</td>
Chris@1 54 </tr>
Chris@1 55 <tr valign=top>
Chris@1 56 <td><a href="ov_open.html">ov_open</a></td>
Chris@1 57 <td>Initializes the Ogg Vorbis bitstream with default values from a passed in file handle. This must be called before other functions in the library may be
Chris@1 58 used. <a href="#winfoot"><em>Do not use this call under Windows [a];</em></a> Use <a href="ov_fopen.html">ov_fopen()</a> or <a href="ov_open_callbacks.html">ov_open_callbacks()</a> instead.</td>
Chris@1 59 </tr>
Chris@1 60 <tr valign=top>
Chris@1 61 <td><a href="ov_open_callbacks.html">ov_open_callbacks</a></td>
Chris@1 62 <td>Initializes the Ogg Vorbis bitstream from a file handle and custom file/bitstream manipulation routines. Used instead of <a href="ov_open.html">ov_open()</a> or <a href="ov_fopen.html">ov_fopen()</a> when altering or replacing libvorbis's default stdio I/O behavior, or when a bitstream must be initialized from a <tt>FILE *</tt> under Windows.</td>
Chris@1 63 </tr>
Chris@1 64
Chris@1 65 <tr valign=top>
Chris@1 66 <td><a href="ov_test.html">ov_test</a></td>
Chris@1 67
Chris@1 68 <td>Partially opens a file just far enough to determine if the file
Chris@1 69 is an Ogg Vorbis file or not. A successful return indicates that the
Chris@1 70 file appears to be an Ogg Vorbis file, but the <a
Chris@1 71 href="OggVorbis_File.html">OggVorbis_File</a> struct is not yet fully
Chris@1 72 initialized for actual decoding. After a <a href="../libvorbis/return.html">successful return</a>, the file
Chris@1 73 may be closed using <a href="ov_clear.html">ov_clear()</a> or fully
Chris@1 74 opened for decoding using <a
Chris@1 75 href="ov_test_open.html">ov_test_open()</a>.<p> This call is intended to
Chris@1 76 be used as a less expensive file open test than a full <a
Chris@1 77 href="ov_open.html">ov_open()</a>.<p>
Chris@1 78 Note that libvorbisfile owns the passed in file resource is it returns success; do not <tt>fclose()</tt> files owned by libvorbisfile.</td>
Chris@1 79
Chris@1 80 </tr>
Chris@1 81 <tr valign=top>
Chris@1 82 <td><a href="ov_test_callbacks.html">ov_test_callbacks</a></td>
Chris@1 83 <td>As above but allowing application-define I/O callbacks.<p>
Chris@1 84 Note that libvorbisfile owns the passed in file resource is it returns success; do not <tt>fclose()</tt> files owned by libvorbisfile.</td>
Chris@1 85
Chris@1 86 </tr>
Chris@1 87 <tr valign=top>
Chris@1 88 <td><a href="ov_test_open.html">ov_test_open</a><td>
Chris@1 89 Finish opening a file after a successful call to <a href="ov_test.html">ov_test()</a> or <a href="ov_test_callbacks.html">ov_test_callbacks()</a>.</td>
Chris@1 90 </tr>
Chris@1 91 <tr valign=top>
Chris@1 92 <td><a href="ov_clear.html">ov_clear</a></td> <td>Closes the
Chris@1 93 bitstream and cleans up loose ends. Must be called when
Chris@1 94 finished with the bitstream. After return, the <a
Chris@1 95 href="OggVorbis_File.html">OggVorbis_File</a> struct is
Chris@1 96 invalid and may not be used before being initialized again
Chris@1 97 before begin reinitialized.
Chris@1 98
Chris@1 99 </td>
Chris@1 100 </tr>
Chris@1 101 </table>
Chris@1 102
Chris@1 103 <br><br>
Chris@1 104 <hr noshade>
Chris@1 105
Chris@1 106 <table border=0 width=100%>
Chris@1 107 <tr valign=top>
Chris@1 108 <td><p class=tiny>copyright &copy; 2000-2010 Xiph.Org</p></td>
Chris@1 109 <td align=right><p class=tiny><a href="http://www.xiph.org/ogg/vorbis/">Ogg Vorbis</a></p></td>
Chris@1 110 </tr><tr>
Chris@1 111 <td><p class=tiny>Vorbisfile documentation</p></td>
Chris@1 112 <td align=right><p class=tiny>vorbisfile version 1.3.2 - 20101101</p></td>
Chris@1 113 </tr>
Chris@1 114 </table>
Chris@1 115
Chris@1 116 </body>
Chris@1 117
Chris@1 118 </html>