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<title>Vorbisfile - datatype - OggVorbis_File</title>
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<td><p class=tiny>Vorbisfile documentation</p></td>
<td align=right><p class=tiny>vorbisfile version 1.2.0 - 20070723</p></td>
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<h1>OggVorbis_File</h1>
<p><i>declared in "vorbis/vorbisfile.h"</i></p>
<p>
The OggVorbis_File structure defines an Ogg Vorbis file.
<p>
This structure is used in all libvorbisfile routines. Before it can
be used, it must be initialized by <a
href="ov_open.html">ov_open()</a>, <a
href="ov_fopen.html">ov_fopen()</a>, or <a
href="ov_open_callbacks.html">ov_open_callbacks()</a>. <em>Important
Note:</em> The use of <a href="ov_open.html">ov_open()</a> is
discouraged under Windows due to a peculiarity of Windows linking
convention; use <a href="ov_fopen.html">ov_fopen()</a> or <a
href="ov_open_callbacks.html">ov_open_callbacks()</a> instead. This
caution only applies to Windows; use of <a
href="ov_open.html">ov_open()</a> is appropriate for all other
platforms. See the <a href="ov_open.html">ov_open()</a> page for more
information.
<p>
After use, the OggVorbis_File structure must be deallocated with a
call to <a href="ov_clear.html">ov_clear()</a>.
<p>
Note that once a file handle is passed to a successful <a
href="ov_open.html">ov_open()</a> call, the handle is owned by
libvorbisfile and will be closed by libvorbisfile later during the
call to <a href="ov_clear.html">ov_clear()</a>. The handle should not
be used or closed outside of the libvorbisfile API. Similarly, files
opened by <a href="ov_fopen.html">ov_fopen()</a> will also be closed
internally by vorbisfile in <a href="ov_clear.html">ov_clear()</a>.<p>
<a href="ov_open_callbacks.html">ov_open_callbacks()</a> allows the
application to choose whether libvorbisfile will or will not close the
handle in <a href="ov_clear.html">ov_clear()</a>; see the <a
href="ov_open_callbacks.html">ov_open_callbacks()</a> page for more information.<p>
If a call to <a href="ov_open.html">ov_open()</a> or <a
href="ov_open_callbacks.html">ov_open_callbacks()</a> <b>fails</b>,
libvorbisfile does <b>not</b> assume ownership of the handle and the
application is expected to close it if necessary. A failed <a
href="ov_fopen.html">ov_fopen()</a> call will internally close the
file handle if the open process fails.<p>
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<pre><b>typedef struct {
void *datasource; /* Pointer to a FILE *, etc. */
int seekable;
ogg_int64_t offset;
ogg_int64_t end;
ogg_sync_state oy;
/* If the FILE handle isn't seekable (eg, a pipe), only the current
stream appears */
int links;
ogg_int64_t *offsets;
ogg_int64_t *dataoffsets;
long *serialnos;
ogg_int64_t *pcmlengths;
vorbis_info *vi;
vorbis_comment *vc;
/* Decoding working state local storage */
ogg_int64_t pcm_offset;
int ready_state;
long current_serialno;
int current_link;
ogg_int64_t bittrack;
ogg_int64_t samptrack;
ogg_stream_state os; /* take physical pages, weld into a logical
stream of packets */
vorbis_dsp_state vd; /* central working state for the packet->PCM decoder */
vorbis_block vb; /* local working space for packet->PCM decode */
<a href="ov_callbacks.html">ov_callbacks</a> callbacks;
} OggVorbis_File;</b></pre>
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<h3>Relevant Struct Members</h3>
<dl>
<dt><i>datasource</i></dt>
<dd>Pointer to file or other ogg source. When using stdio based
file/stream access, this field contains a <tt>FILE</tt> pointer. When using
custom IO via callbacks, libvorbisfile treats this void pointer as a
black box only to be passed to the callback routines provided by the
application.</dd>
<dt><i>seekable</i></dt>
<dd>Read-only int indicating whether file is seekable. E.g., a physical file is seekable, a pipe isn't.</dd>
<dt><i>links</i></dt>
<dd>Read-only int indicating the number of logical bitstreams within the physical bitstream.</dd>
<dt><i>ov_callbacks</i></dt>
<dd>Collection of file manipulation routines to be used on this data source. When using stdio/FILE access via <a href="ov_open.html">ov_open()</a>, the callbacks will be filled in with stdio calls or wrappers to stdio calls.</dd>
</dl>
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<td><p class=tiny>copyright © 2007 Xiph.org</p></td>
<td align=right><p class=tiny><a href="http://www.xiph.org/ogg/vorbis/">Ogg Vorbis</a></p></td>
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<td><p class=tiny>Vorbisfile documentation</p></td>
<td align=right><p class=tiny>vorbisfile version 1.2.0 - 20070723</p></td>
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