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diff --git a/doc/vorbisfile/ov_fopen.html b/doc/vorbisfile/ov_fopen.html new file mode 100644 index 0000000..9a7b14b --- /dev/null +++ b/doc/vorbisfile/ov_fopen.html @@ -0,0 +1,124 @@ +<html> + +<head> +<title>Vorbisfile - function - ov_fopen</title> +<link rel=stylesheet href="style.css" type="text/css"> +</head> + +<body bgcolor=white text=black link="#5555ff" alink="#5555ff" vlink="#5555ff"> +<table border=0 width=100%> +<tr> +<td><p class=tiny>Vorbisfile documentation</p></td> +<td align=right><p class=tiny>vorbisfile version 1.3.2 - 20101101</p></td> +</tr> +</table> + +<h1>ov_fopen</h1> + +<p><i>declared in "vorbis/vorbisfile.h";</i></p> + +<p>This is the simplest function used to open and initialize an OggVorbis_File +structure. It sets up all the related decoding structure. +<p>The first argument is a file path suitable +for passing to fopen(). <tt>vf</tt> should be a pointer to an empty +OggVorbis_File structure -- this is used for ALL the externally visible +libvorbisfile functions. Once this has been called, the same <a +href="OggVorbis_File.html">OggVorbis_File</a> struct should be passed +to all the libvorbisfile functions. +<p>The <tt>vf</tt> structure initialized using ov_fopen() must +eventually be cleaned using <a href="ov_clear.html">ov_clear()</a>. + +<p> +It is often useful to call <tt>ov_fopen()</tt> simply to determine +whether a given file is a Vorbis bitstream. If the <tt>ov_fopen()</tt> +call fails, then the file is either inaccessable (errno is set) or not +recognizable as Vorbis (errno unchanged). If the call succeeds but +the initialized <tt>vf</tt> structure will not be used, the +application is responsible for calling <a +href="ov_clear.html">ov_clear()</a> to clear the decoder's buffers and +close the file.<p> + +<br><br> +<table border=0 color=black cellspacing=0 cellpadding=7> +<tr bgcolor=#cccccc> + <td> +<pre><b> +int ov_fopen(const char *path,<a href="OggVorbis_File.html">OggVorbis_File</a> *vf); +</b></pre> + </td> +</tr> +</table> + +<h3>Parameters</h3> +<dl> +<dt><i>path</i></dt> +<dd>Null terminated string containing a file path suitable for passing to <tt>fopen()</tt>. +</dd> +<dt><i>vf</i></dt> +<dd>A pointer to the OggVorbis_File structure--this is used for ALL the externally visible libvorbisfile +functions. Once this has been called, the same <tt>OggVorbis_File</tt> +struct should be passed to all the libvorbisfile functions.</dd> +</dl> + + +<h3>Return Values</h3> +<blockquote> +<li>0 indicates success</li> + +<li>less than zero for failure:</li> +<ul> +<li>OV_EREAD - A read from media returned an error.</li> +<li>OV_ENOTVORBIS - Bitstream does not contain any Vorbis data.</li> +<li>OV_EVERSION - Vorbis version mismatch.</li> +<li>OV_EBADHEADER - Invalid Vorbis bitstream header.</li> +<li>OV_EFAULT - Internal logic fault; indicates a bug or heap/stack corruption.</li> +</ul> +</blockquote> +<p> + +<h3>Notes</h3> +<dl> + +<dt><b>[a] Threaded decode</b><p> +<dd>If your decoder is threaded, it is recommended that you NOT call +<tt>ov_open_callbacks()</tt> +in the main control thread--instead, call <tt>ov_open_callbacks()</tt> in your decode/playback +thread. This is important because <tt>ov_open_callbacks()</tt> may be a fairly time-consuming +call, given that the full structure of the file is determined at this point, +which may require reading large parts of the file under certain circumstances +(determining all the logical bitstreams in one physical bitstream, for +example). See <a href="threads.html">Thread Safety</a> for other information on using libvorbisfile with threads. +<p> + +<dt><b>[b] Mixed media streams</b><p> +<dd> +As of Vorbisfile release 1.2.0, Vorbisfile is able to access the +Vorbis content in mixed-media Ogg streams, not just Vorbis-only +streams. For example, Vorbisfile may be used to open and access the +audio from an Ogg stream consisting of Theora video and Vorbis audio. +Vorbisfile 1.2.0 decodes the first logical audio stream of each +physical stream section.<p> + +<dt><b>[c] Faster testing for Vorbis files</b><p> +<dd><a href="ov_test.html">ov_test()</a> and <a +href="ov_test_callbacks.html">ov_test_callbacks()</a> provide less +computationally expensive ways to test a file for Vorbisness, but +require more setup code.<p> + +</dl> + +<br><br> +<hr noshade> +<table border=0 width=100%> +<tr valign=top> +<td><p class=tiny>copyright © 2000-2010 Xiph.Org</p></td> +<td align=right><p class=tiny><a href="http://www.xiph.org/ogg/vorbis/">Ogg Vorbis</a></p></td> +</tr><tr> +<td><p class=tiny>Vorbisfile documentation</p></td> +<td align=right><p class=tiny>vorbisfile version 1.3.2 - 20101101</p></td> +</tr> +</table> + +</body> + +</html> |