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  26                   <a href="#gstreamer-GstFormat.description" class="shortcut">Description</a>
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  29 <div class="refentry">
  30 <a name="gstreamer-GstFormat"></a><div class="titlepage"></div>
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  32 <td valign="top">
  33 <h2><span class="refentrytitle"><a name="gstreamer-GstFormat.top_of_page"></a>GstFormat</span></h2>
  34 <p>GstFormat — Dynamically register new data formats</p>
  35 </td>
  36 <td valign="top" align="right"></td>
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  38 <div class="refsynopsisdiv">
  39 <a name="gstreamer-GstFormat.synopsis"></a><h2>Synopsis</h2>
  40 <pre class="synopsis">
  41 #include &lt;gst/gst.h&gt;
  42
  43 enum                <a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat">GstFormat</a>;
  44 #define             <a class="link" href="gstreamer-GstFormat.html#GST-FORMAT-PERCENT-MAX:CAPS" title="GST_FORMAT_PERCENT_MAX">GST_FORMAT_PERCENT_MAX</a>
  45 #define             <a class="link" href="gstreamer-GstFormat.html#GST-FORMAT-PERCENT-SCALE:CAPS" title="GST_FORMAT_PERCENT_SCALE">GST_FORMAT_PERCENT_SCALE</a>
  46 struct              <a class="link" href="gstreamer-GstFormat.html#GstFormatDefinition" title="struct GstFormatDefinition">GstFormatDefinition</a>;
  47 const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="returnvalue">gchar</span></a> *       <a class="link" href="gstreamer-GstFormat.html#gst-format-get-name" title="gst_format_get_name ()">gst_format_get_name</a>                 (<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>);
  48 <a href="http://library.gnome.org/devel/glib/unstable/glib-Quarks.html#GQuark"><span class="returnvalue">GQuark</span></a>              <a class="link" href="gstreamer-GstFormat.html#gst-format-to-quark" title="gst_format_to_quark ()">gst_format_to_quark</a>                 (<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>);
  49 <a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="returnvalue">GstFormat</span></a>           <a class="link" href="gstreamer-GstFormat.html#gst-format-register" title="gst_format_register ()">gst_format_register</a>                 (<em class="parameter"><code>const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *nick</code></em>,
  50                                                          <em class="parameter"><code>const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *description</code></em>);
  51 <a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="returnvalue">GstFormat</span></a>           <a class="link" href="gstreamer-GstFormat.html#gst-format-get-by-nick" title="gst_format_get_by_nick ()">gst_format_get_by_nick</a>              (<em class="parameter"><code>const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *nick</code></em>);
  52 <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>            <a class="link" href="gstreamer-GstFormat.html#gst-formats-contains" title="gst_formats_contains ()">gst_formats_contains</a>                (<em class="parameter"><code>const <a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> *formats</code></em>,
  53                                                          <em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>);
  54 const <a class="link" href="gstreamer-GstFormat.html#GstFormatDefinition" title="struct GstFormatDefinition"><span class="returnvalue">GstFormatDefinition</span></a> * <a class="link" href="gstreamer-GstFormat.html#gst-format-get-details" title="gst_format_get_details ()">gst_format_get_details</a>      (<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>);
  55 <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *       <a class="link" href="gstreamer-GstFormat.html#gst-format-iterate-definitions" title="gst_format_iterate_definitions ()">gst_format_iterate_definitions</a>      (<em class="parameter"><code><span class="type">void</span></code></em>);
  56 </pre>
  57 </div>
  58 <div class="refsect1">
  59 <a name="gstreamer-GstFormat.description"></a><h2>Description</h2>
  60 <p>
  61 GstFormats functions are used to register a new format to the gstreamer
  62 core.  Formats can be used to perform seeking or conversions/query
  63 operations.
  64 </p>
  65 </div>
  66 <div class="refsect1">
  67 <a name="gstreamer-GstFormat.details"></a><h2>Details</h2>
  68 <div class="refsect2">
  69 <a name="GstFormat"></a><h3>enum GstFormat</h3>
  70 <pre class="programlisting">typedef enum {
  71   GST_FORMAT_UNDEFINED  =  0, /* must be first in list */
  72   GST_FORMAT_DEFAULT    =  1,
  73   GST_FORMAT_BYTES      =  2,
  74   GST_FORMAT_TIME       =  3,
  75   GST_FORMAT_BUFFERS =  4,
  76   GST_FORMAT_PERCENT =  5
  77 } GstFormat;
  78 </pre>
  79 <p>
  80 Standard predefined formats
  81 </p>
  82 <div class="variablelist"><table border="0">
  83 <col align="left" valign="top">
  84 <tbody>
  85 <tr>
  86 <td><p><a name="GST-FORMAT-UNDEFINED:CAPS"></a><span class="term"><code class="literal">GST_FORMAT_UNDEFINED</code></span></p></td>
  87 <td>undefined format
  88 </td>
  89 </tr>
  90 <tr>
  91 <td><p><a name="GST-FORMAT-DEFAULT:CAPS"></a><span class="term"><code class="literal">GST_FORMAT_DEFAULT</code></span></p></td>
  92 <td>the default format of the pad/element. This can be
  93    samples for raw audio, frames/fields for raw video (some, but not all,
  94    elements support this; use <em class="parameter"><code>GST_FORMAT_TIME</code></em> if you don't have a good
  95    reason to query for samples/frames)
  96 </td>
  97 </tr>
  98 <tr>
  99 <td><p><a name="GST-FORMAT-BYTES:CAPS"></a><span class="term"><code class="literal">GST_FORMAT_BYTES</code></span></p></td>
 100 <td>bytes
 101 </td>
 102 </tr>
 103 <tr>
 104 <td><p><a name="GST-FORMAT-TIME:CAPS"></a><span class="term"><code class="literal">GST_FORMAT_TIME</code></span></p></td>
 105 <td>time in nanoseconds
 106 </td>
 107 </tr>
 108 <tr>
 109 <td><p><a name="GST-FORMAT-BUFFERS:CAPS"></a><span class="term"><code class="literal">GST_FORMAT_BUFFERS</code></span></p></td>
 110 <td>buffers (few, if any, elements implement this as of
 111     May 2009)
 112 </td>
 113 </tr>
 114 <tr>
 115 <td><p><a name="GST-FORMAT-PERCENT:CAPS"></a><span class="term"><code class="literal">GST_FORMAT_PERCENT</code></span></p></td>
 116 <td>percentage of stream (few, if any, elements implement
 117     this as of May 2009)
 118 </td>
 119 </tr>
 120 </tbody>
 121 </table></div>
 122 </div>
 123 <hr>
 124 <div class="refsect2">
 125 <a name="GST-FORMAT-PERCENT-MAX:CAPS"></a><h3>GST_FORMAT_PERCENT_MAX</h3>
 126 <pre class="programlisting">#define GST_FORMAT_PERCENT_MAX             G_GINT64_CONSTANT (1000000)
 127 </pre>
 128 <p>
 129 The PERCENT format is between 0 and this value
 130 </p>
 131 </div>
 132 <hr>
 133 <div class="refsect2">
 134 <a name="GST-FORMAT-PERCENT-SCALE:CAPS"></a><h3>GST_FORMAT_PERCENT_SCALE</h3>
 135 <pre class="programlisting">#define GST_FORMAT_PERCENT_SCALE G_GINT64_CONSTANT (10000)
 136 </pre>
 137 <p>
 138 The value used to scale down the reported PERCENT format value to
 139 its real value.
 140 </p>
 141 </div>
 142 <hr>
 143 <div class="refsect2">
 144 <a name="GstFormatDefinition"></a><h3>struct GstFormatDefinition</h3>
 145 <pre class="programlisting">struct GstFormatDefinition {
 146   GstFormat    value;
 147   const gchar *nick;
 148   const gchar *description;
 149   GQuark       quark;
 150 };
 151 </pre>
 152 <p>
 153 A format definition
 154 </p>
 155 <div class="variablelist"><table border="0">
 156 <col align="left" valign="top">
 157 <tbody>
 158 <tr>
 159 <td><p><span class="term"><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> <em class="structfield"><code><a name="GstFormatDefinition.value"></a>value</code></em>;</span></p></td>
 160 <td>The unique id of this format</td>
 161 </tr>
 162 <tr>
 163 <td><p><span class="term">const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *<em class="structfield"><code><a name="GstFormatDefinition.nick"></a>nick</code></em>;</span></p></td>
 164 <td>A short nick of the format</td>
 165 </tr>
 166 <tr>
 167 <td><p><span class="term">const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *<em class="structfield"><code><a name="GstFormatDefinition.description"></a>description</code></em>;</span></p></td>
 168 <td>A longer description of the format</td>
 169 </tr>
 170 <tr>
 171 <td><p><span class="term"><a href="http://library.gnome.org/devel/glib/unstable/glib-Quarks.html#GQuark"><span class="type">GQuark</span></a> <em class="structfield"><code><a name="GstFormatDefinition.quark"></a>quark</code></em>;</span></p></td>
 172 <td>A quark for the nick</td>
 173 </tr>
 174 </tbody>
 175 </table></div>
 176 </div>
 177 <hr>
 178 <div class="refsect2">
 179 <a name="gst-format-get-name"></a><h3>gst_format_get_name ()</h3>
 180 <pre class="programlisting">const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="returnvalue">gchar</span></a> *       gst_format_get_name                 (<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>);</pre>
 181 <p>
 182 Get a printable name for the given format. Do not modify or free.
 183 </p>
 184 <div class="variablelist"><table border="0">
 185 <col align="left" valign="top">
 186 <tbody>
 187 <tr>
 188 <td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
 189 <td>a <a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a>
 190 </td>
 191 </tr>
 192 <tr>
 193 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 194 <td>a reference to the static name of the format or NULL if
 195 the format is unknown.</td>
 196 </tr>
 197 </tbody>
 198 </table></div>
 199 </div>
 200 <hr>
 201 <div class="refsect2">
 202 <a name="gst-format-to-quark"></a><h3>gst_format_to_quark ()</h3>
 203 <pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Quarks.html#GQuark"><span class="returnvalue">GQuark</span></a>              gst_format_to_quark                 (<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>);</pre>
 204 <p>
 205 Get the unique quark for the given format.
 206 </p>
 207 <div class="variablelist"><table border="0">
 208 <col align="left" valign="top">
 209 <tbody>
 210 <tr>
 211 <td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
 212 <td>a <a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a>
 213 </td>
 214 </tr>
 215 <tr>
 216 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 217 <td>the quark associated with the format or 0 if the format
 218 is unknown.</td>
 219 </tr>
 220 </tbody>
 221 </table></div>
 222 </div>
 223 <hr>
 224 <div class="refsect2">
 225 <a name="gst-format-register"></a><h3>gst_format_register ()</h3>
 226 <pre class="programlisting"><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="returnvalue">GstFormat</span></a>           gst_format_register                 (<em class="parameter"><code>const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *nick</code></em>,
 227                                                          <em class="parameter"><code>const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *description</code></em>);</pre>
 228 <p>
 229 Create a new GstFormat based on the nick or return an
 230 already registered format with that nick.
 231 </p>
 232 <div class="variablelist"><table border="0">
 233 <col align="left" valign="top">
 234 <tbody>
 235 <tr>
 236 <td><p><span class="term"><em class="parameter"><code>nick</code></em> :</span></p></td>
 237 <td>The nick of the new format</td>
 238 </tr>
 239 <tr>
 240 <td><p><span class="term"><em class="parameter"><code>description</code></em> :</span></p></td>
 241 <td>The description of the new format</td>
 242 </tr>
 243 <tr>
 244 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 245 <td>A new GstFormat or an already registered format
 246 with the same nick.
 247 MT safe.</td>
 248 </tr>
 249 </tbody>
 250 </table></div>
 251 </div>
 252 <hr>
 253 <div class="refsect2">
 254 <a name="gst-format-get-by-nick"></a><h3>gst_format_get_by_nick ()</h3>
 255 <pre class="programlisting"><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="returnvalue">GstFormat</span></a>           gst_format_get_by_nick              (<em class="parameter"><code>const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *nick</code></em>);</pre>
 256 <p>
 257 Return the format registered with the given nick.
 258 </p>
 259 <div class="variablelist"><table border="0">
 260 <col align="left" valign="top">
 261 <tbody>
 262 <tr>
 263 <td><p><span class="term"><em class="parameter"><code>nick</code></em> :</span></p></td>
 264 <td>The nick of the format</td>
 265 </tr>
 266 <tr>
 267 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 268 <td>The format with <em class="parameter"><code>nick</code></em> or GST_FORMAT_UNDEFINED
 269 if the format was not registered.</td>
 270 </tr>
 271 </tbody>
 272 </table></div>
 273 </div>
 274 <hr>
 275 <div class="refsect2">
 276 <a name="gst-formats-contains"></a><h3>gst_formats_contains ()</h3>
 277 <pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>            gst_formats_contains                (<em class="parameter"><code>const <a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> *formats</code></em>,
 278                                                          <em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>);</pre>
 279 <p>
 280 See if the given format is inside the format array.
 281 </p>
 282 <div class="variablelist"><table border="0">
 283 <col align="left" valign="top">
 284 <tbody>
 285 <tr>
 286 <td><p><span class="term"><em class="parameter"><code>formats</code></em> :</span></p></td>
 287 <td>The format array to search</td>
 288 </tr>
 289 <tr>
 290 <td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
 291 <td>the format to find</td>
 292 </tr>
 293 <tr>
 294 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 295 <td>TRUE if the format is found inside the array</td>
 296 </tr>
 297 </tbody>
 298 </table></div>
 299 </div>
 300 <hr>
 301 <div class="refsect2">
 302 <a name="gst-format-get-details"></a><h3>gst_format_get_details ()</h3>
 303 <pre class="programlisting">const <a class="link" href="gstreamer-GstFormat.html#GstFormatDefinition" title="struct GstFormatDefinition"><span class="returnvalue">GstFormatDefinition</span></a> * gst_format_get_details      (<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>);</pre>
 304 <p>
 305 Get details about the given format.
 306 </p>
 307 <div class="variablelist"><table border="0">
 308 <col align="left" valign="top">
 309 <tbody>
 310 <tr>
 311 <td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
 312 <td>The format to get details of</td>
 313 </tr>
 314 <tr>
 315 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 316 <td>The <a class="link" href="gstreamer-GstFormat.html#GstFormatDefinition" title="struct GstFormatDefinition"><span class="type">GstFormatDefinition</span></a> for <em class="parameter"><code>format</code></em> or NULL on failure.
 317 MT safe.</td>
 318 </tr>
 319 </tbody>
 320 </table></div>
 321 </div>
 322 <hr>
 323 <div class="refsect2">
 324 <a name="gst-format-iterate-definitions"></a><h3>gst_format_iterate_definitions ()</h3>
 325 <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *       gst_format_iterate_definitions      (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
 326 <p>
 327 Iterate all the registered formats. The format definition is read
 328 only.
 329 </p>
 330 <div class="variablelist"><table border="0">
 331 <col align="left" valign="top">
 332 <tbody><tr>
 333 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 334 <td>a GstIterator of <a class="link" href="gstreamer-GstFormat.html#GstFormatDefinition" title="struct GstFormatDefinition"><span class="type">GstFormatDefinition</span></a>. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span>
 335 </td>
 336 </tr></tbody>
 337 </table></div>
 338 </div>
 339 </div>
 340 <div class="refsect1">
 341 <a name="gstreamer-GstFormat.see-also"></a><h2>See Also</h2>
 342 <a class="link" href="GstPad.html" title="GstPad"><span class="type">GstPad</span></a>, <a class="link" href="GstElement.html" title="GstElement"><span class="type">GstElement</span></a>
 343 </div>
 344 </div>
 345 <div class="footer">
 346 <hr>
 347           Generated by GTK-Doc V1.18</div>
 348 </body>
 349 </html>