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<h1>Helper Functions<br/>
<small>
[<a class="el" href="group___p_c_m.html">PCM Interface</a>]</small>
</h1><table border="0" cellpadding="0" cellspacing="0">
<tr><td colspan="2"><h2>Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga8b88181b11a026da55897a926d56034a">snd_pcm_format_signed</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return sign info for a PCM sample linear format. <a href="#ga8b88181b11a026da55897a926d56034a"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga8cd4e3ecc963942457e3b1b6f7661a90">snd_pcm_format_unsigned</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return sign info for a PCM sample linear format. <a href="#ga8cd4e3ecc963942457e3b1b6f7661a90"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga5a52bb63323f463198dea3f3c6aca571">snd_pcm_format_linear</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return linear info for a PCM sample format. <a href="#ga5a52bb63323f463198dea3f3c6aca571"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga36ae70bef5bfd5e7ecc743f6a4d46cb5">snd_pcm_format_float</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return float info for a PCM sample format. <a href="#ga36ae70bef5bfd5e7ecc743f6a4d46cb5"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga89537d0a972fa124051f6ba1a78c4bfa">snd_pcm_format_little_endian</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return endian info for a PCM sample format. <a href="#ga89537d0a972fa124051f6ba1a78c4bfa"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga3c0c224b8f67e73cf2447bee0110f760">snd_pcm_format_big_endian</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return endian info for a PCM sample format. <a href="#ga3c0c224b8f67e73cf2447bee0110f760"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#gaf950358cdbb26bab53f63f28443bd2ef">snd_pcm_format_cpu_endian</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return endian info for a PCM sample format. <a href="#gaf950358cdbb26bab53f63f28443bd2ef"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga8d4e07f2d68cc16f607857ed8a222a29">snd_pcm_format_width</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return nominal bits per a PCM sample. <a href="#ga8d4e07f2d68cc16f607857ed8a222a29"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#gaa3e0ff7560342e5af2b5c7bd2d63a307">snd_pcm_format_physical_width</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return bits needed to store a PCM sample. <a href="#gaa3e0ff7560342e5af2b5c7bd2d63a307"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga5f5ab1ac13de9598cf05877e4894e0d8">snd_pcm_build_linear_format</a> (int width, int pwidth, int unsignd, int big_endian)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Compose a PCM sample linear format. <a href="#ga5f5ab1ac13de9598cf05877e4894e0d8"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">ssize_t </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga5953a58f024f8cf762a9e4dae6b09502">snd_pcm_format_size</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format, size_t samples)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return bytes needed to store a quantity of PCM sample. <a href="#ga5953a58f024f8cf762a9e4dae6b09502"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">u_int8_t </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga812a6458ab7759b750d6954050c75bb2">snd_pcm_format_silence</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return 8 bit expressing silence for a PCM sample format. <a href="#ga812a6458ab7759b750d6954050c75bb2"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">u_int16_t </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga6602d717534a0b6857f461fef1d8b37c">snd_pcm_format_silence_16</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return 16 bit expressing silence for a PCM sample format. <a href="#ga6602d717534a0b6857f461fef1d8b37c"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">u_int32_t </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#gafbf8a883e8b7c38b94df561e0169aef4">snd_pcm_format_silence_32</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return 32 bit expressing silence for a PCM sample format. <a href="#gafbf8a883e8b7c38b94df561e0169aef4"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">u_int64_t </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga79524557a85d7bbee12d315925e702b3">snd_pcm_format_silence_64</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return 64 bit expressing silence for a PCM sample format. <a href="#ga79524557a85d7bbee12d315925e702b3"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga82631361cf1c1d13af207beb59cf97ac">snd_pcm_format_set_silence</a> (<a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format, void *buf, unsigned int samples)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Silence a PCM samples buffer. <a href="#ga82631361cf1c1d13af207beb59cf97ac"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="el" href="group___p_c_m.html#ga71cdfa37e258d2210b8bd0216bf0c36c">snd_pcm_sframes_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#gaf42fb6af35d3d85006c1dea2e11b3e54">snd_pcm_bytes_to_frames</a> (<a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> *pcm, ssize_t bytes)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Convert bytes in frames for a PCM. <a href="#gaf42fb6af35d3d85006c1dea2e11b3e54"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">ssize_t </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#gac05ac2b7c6e25986a71792392ff90b83">snd_pcm_frames_to_bytes</a> (<a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> *pcm, <a class="el" href="group___p_c_m.html#ga71cdfa37e258d2210b8bd0216bf0c36c">snd_pcm_sframes_t</a> frames)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Convert frames in bytes for a PCM. <a href="#gac05ac2b7c6e25986a71792392ff90b83"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">long </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#gaeed610ddb01120b01b5a2e5cc59aa35b">snd_pcm_bytes_to_samples</a> (<a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> *pcm, ssize_t bytes)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Convert bytes in samples for a PCM. <a href="#gaeed610ddb01120b01b5a2e5cc59aa35b"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">ssize_t </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#gae3669a4326ce185f4261d7bf96900f3f">snd_pcm_samples_to_bytes</a> (<a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> *pcm, long samples)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Convert samples in bytes for a PCM. <a href="#gae3669a4326ce185f4261d7bf96900f3f"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga23e03a8b127764fff669240986b96b39">snd_pcm_area_silence</a> (const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> *dst_channel, <a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> dst_offset, unsigned int samples, <a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Silence an area. <a href="#ga23e03a8b127764fff669240986b96b39"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga1c0aab2a2bb341f1b1d154dae2b7e482">snd_pcm_areas_silence</a> (const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> *dst_channels, <a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> dst_offset, unsigned int channels, <a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> frames, <a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Silence one or more areas. <a href="#ga1c0aab2a2bb341f1b1d154dae2b7e482"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#ga93d2f045575afb161abff126c3750049">snd_pcm_area_copy</a> (const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> *dst_channel, <a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> dst_offset, const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> *src_channel, <a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> src_offset, unsigned int samples, <a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Copy an area. <a href="#ga93d2f045575afb161abff126c3750049"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___helpers.html#gad57f8921f52ea2ffd870cafb2d076f2c">snd_pcm_areas_copy</a> (const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> *dst_channels, <a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> dst_offset, const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> *src_channels, <a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> src_offset, unsigned int channels, <a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> frames, <a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> format)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Copy one or more areas. <a href="#gad57f8921f52ea2ffd870cafb2d076f2c"></a><br/></td></tr>
</table>
<hr/><a name="_details"></a><h2>Detailed Description</h2>
<p>See the <a class="el" href="pcm.html">PCM (digital audio) interface</a> page for more details. </p>
<hr/><h2>Function Documentation</h2>
<a class="anchor" id="ga93d2f045575afb161abff126c3750049"></a><!-- doxytag: member="pcm.h::snd_pcm_area_copy" ref="ga93d2f045575afb161abff126c3750049" args="(const snd_pcm_channel_area_t *dst_channel, snd_pcm_uframes_t dst_offset, const snd_pcm_channel_area_t *src_channel, snd_pcm_uframes_t src_offset, unsigned int samples, snd_pcm_format_t format)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int snd_pcm_area_copy </td>
<td>(</td>
<td class="paramtype">const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> * </td>
<td class="paramname"> <em>dst_area</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> </td>
<td class="paramname"> <em>dst_offset</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> * </td>
<td class="paramname"> <em>src_area</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> </td>
<td class="paramname"> <em>src_offset</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">unsigned int </td>
<td class="paramname"> <em>samples</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Copy an area. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>dst_area</em> </td><td>destination area specification </td></tr>
<tr><td valign="top"></td><td valign="top"><em>dst_offset</em> </td><td>offset in frames inside destination area </td></tr>
<tr><td valign="top"></td><td valign="top"><em>src_area</em> </td><td>source area specification </td></tr>
<tr><td valign="top"></td><td valign="top"><em>src_offset</em> </td><td>offset in frames inside source area </td></tr>
<tr><td valign="top"></td><td valign="top"><em>samples</em> </td><td>samples to copy </td></tr>
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>PCM sample format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 on success otherwise a negative error code </dd></dl>
</div>
</div>
<a class="anchor" id="ga23e03a8b127764fff669240986b96b39"></a><!-- doxytag: member="pcm.h::snd_pcm_area_silence" ref="ga23e03a8b127764fff669240986b96b39" args="(const snd_pcm_channel_area_t *dst_channel, snd_pcm_uframes_t dst_offset, unsigned int samples, snd_pcm_format_t format)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
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<td class="memname">int snd_pcm_area_silence </td>
<td>(</td>
<td class="paramtype">const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> * </td>
<td class="paramname"> <em>dst_area</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> </td>
<td class="paramname"> <em>dst_offset</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">unsigned int </td>
<td class="paramname"> <em>samples</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Silence an area. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>dst_area</em> </td><td>area specification </td></tr>
<tr><td valign="top"></td><td valign="top"><em>dst_offset</em> </td><td>offset in frames inside area </td></tr>
<tr><td valign="top"></td><td valign="top"><em>samples</em> </td><td>samples to silence </td></tr>
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>PCM sample format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 on success otherwise a negative error code </dd></dl>
</div>
</div>
<a class="anchor" id="gad57f8921f52ea2ffd870cafb2d076f2c"></a><!-- doxytag: member="pcm.h::snd_pcm_areas_copy" ref="gad57f8921f52ea2ffd870cafb2d076f2c" args="(const snd_pcm_channel_area_t *dst_channels, snd_pcm_uframes_t dst_offset, const snd_pcm_channel_area_t *src_channels, snd_pcm_uframes_t src_offset, unsigned int channels, snd_pcm_uframes_t frames, snd_pcm_format_t format)" -->
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<td class="memname">int snd_pcm_areas_copy </td>
<td>(</td>
<td class="paramtype">const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> * </td>
<td class="paramname"> <em>dst_areas</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> </td>
<td class="paramname"> <em>dst_offset</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> * </td>
<td class="paramname"> <em>src_areas</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> </td>
<td class="paramname"> <em>src_offset</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">unsigned int </td>
<td class="paramname"> <em>channels</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> </td>
<td class="paramname"> <em>frames</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Copy one or more areas. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>dst_areas</em> </td><td>destination areas specification (one for each channel) </td></tr>
<tr><td valign="top"></td><td valign="top"><em>dst_offset</em> </td><td>offset in frames inside destination area </td></tr>
<tr><td valign="top"></td><td valign="top"><em>src_areas</em> </td><td>source areas specification (one for each channel) </td></tr>
<tr><td valign="top"></td><td valign="top"><em>src_offset</em> </td><td>offset in frames inside source area </td></tr>
<tr><td valign="top"></td><td valign="top"><em>channels</em> </td><td>channels count </td></tr>
<tr><td valign="top"></td><td valign="top"><em>frames</em> </td><td>frames to copy </td></tr>
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>PCM sample format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 on success otherwise a negative error code </dd></dl>
</div>
</div>
<a class="anchor" id="ga1c0aab2a2bb341f1b1d154dae2b7e482"></a><!-- doxytag: member="pcm.h::snd_pcm_areas_silence" ref="ga1c0aab2a2bb341f1b1d154dae2b7e482" args="(const snd_pcm_channel_area_t *dst_channels, snd_pcm_uframes_t dst_offset, unsigned int channels, snd_pcm_uframes_t frames, snd_pcm_format_t format)" -->
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<td class="memname">int snd_pcm_areas_silence </td>
<td>(</td>
<td class="paramtype">const <a class="el" href="structsnd__pcm__channel__area__t.html">snd_pcm_channel_area_t</a> * </td>
<td class="paramname"> <em>dst_areas</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> </td>
<td class="paramname"> <em>dst_offset</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">unsigned int </td>
<td class="paramname"> <em>channels</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gab01fcfe9b97382a8d3f2027c664b8b8a">snd_pcm_uframes_t</a> </td>
<td class="paramname"> <em>frames</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Silence one or more areas. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>dst_areas</em> </td><td>areas specification (one for each channel) </td></tr>
<tr><td valign="top"></td><td valign="top"><em>dst_offset</em> </td><td>offset in frames inside area </td></tr>
<tr><td valign="top"></td><td valign="top"><em>channels</em> </td><td>channels count </td></tr>
<tr><td valign="top"></td><td valign="top"><em>frames</em> </td><td>frames to silence </td></tr>
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>PCM sample format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 on success otherwise a negative error code </dd></dl>
</div>
</div>
<a class="anchor" id="ga5f5ab1ac13de9598cf05877e4894e0d8"></a><!-- doxytag: member="pcm.h::snd_pcm_build_linear_format" ref="ga5f5ab1ac13de9598cf05877e4894e0d8" args="(int width, int pwidth, int unsignd, int big_endian)" -->
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<td class="memname"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> snd_pcm_build_linear_format </td>
<td>(</td>
<td class="paramtype">int </td>
<td class="paramname"> <em>width</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">int </td>
<td class="paramname"> <em>pwidth</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">int </td>
<td class="paramname"> <em>unsignd</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">int </td>
<td class="paramname"> <em>big_endian</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
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<p>Compose a PCM sample linear format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>width</em> </td><td>Nominal bits per sample </td></tr>
<tr><td valign="top"></td><td valign="top"><em>pwidth</em> </td><td>Physical bit width of the format </td></tr>
<tr><td valign="top"></td><td valign="top"><em>unsignd</em> </td><td>Sign: 0 signed, 1 unsigned </td></tr>
<tr><td valign="top"></td><td valign="top"><em>big_endian</em> </td><td>Endian: 0 little endian, 1 big endian </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>The matching format type, or <a class="el" href="group___p_c_m.html#ggaa14b7f26877a812acbb39811364177f8ab1e118ecdccf628639b5c85bc3a48999">SND_PCM_FORMAT_UNKNOWN</a> if no match </dd></dl>
</div>
</div>
<a class="anchor" id="gaf42fb6af35d3d85006c1dea2e11b3e54"></a><!-- doxytag: member="pcm.h::snd_pcm_bytes_to_frames" ref="gaf42fb6af35d3d85006c1dea2e11b3e54" args="(snd_pcm_t *pcm, ssize_t bytes)" -->
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<td class="memname"><a class="el" href="group___p_c_m.html#ga71cdfa37e258d2210b8bd0216bf0c36c">snd_pcm_sframes_t</a> snd_pcm_bytes_to_frames </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> * </td>
<td class="paramname"> <em>pcm</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">ssize_t </td>
<td class="paramname"> <em>bytes</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Convert bytes in frames for a PCM. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>pcm</em> </td><td>PCM handle </td></tr>
<tr><td valign="top"></td><td valign="top"><em>bytes</em> </td><td>quantity in bytes </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>quantity expressed in frames </dd></dl>
</div>
</div>
<a class="anchor" id="gaeed610ddb01120b01b5a2e5cc59aa35b"></a><!-- doxytag: member="pcm.h::snd_pcm_bytes_to_samples" ref="gaeed610ddb01120b01b5a2e5cc59aa35b" args="(snd_pcm_t *pcm, ssize_t bytes)" -->
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<td class="memname">long snd_pcm_bytes_to_samples </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> * </td>
<td class="paramname"> <em>pcm</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">ssize_t </td>
<td class="paramname"> <em>bytes</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Convert bytes in samples for a PCM. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>pcm</em> </td><td>PCM handle </td></tr>
<tr><td valign="top"></td><td valign="top"><em>bytes</em> </td><td>quantity in bytes </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>quantity expressed in samples </dd></dl>
</div>
</div>
<a class="anchor" id="ga3c0c224b8f67e73cf2447bee0110f760"></a><!-- doxytag: member="pcm.h::snd_pcm_format_big_endian" ref="ga3c0c224b8f67e73cf2447bee0110f760" args="(snd_pcm_format_t format)" -->
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<td class="memname">int snd_pcm_format_big_endian </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return endian info for a PCM sample format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 little endian, 1 big endian, a negative error code if endian independent </dd></dl>
<dl><dt><b>Examples: </b></dt><dd><a class="el" href="_2test_2pcm_8c-example.html#a7">/test/pcm.c</a>.</dd>
</dl>
</div>
</div>
<a class="anchor" id="gaf950358cdbb26bab53f63f28443bd2ef"></a><!-- doxytag: member="pcm.h::snd_pcm_format_cpu_endian" ref="gaf950358cdbb26bab53f63f28443bd2ef" args="(snd_pcm_format_t format)" -->
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<td class="memname">int snd_pcm_format_cpu_endian </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return endian info for a PCM sample format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 swapped, 1 CPU endian, a negative error code if endian independent </dd></dl>
</div>
</div>
<a class="anchor" id="ga36ae70bef5bfd5e7ecc743f6a4d46cb5"></a><!-- doxytag: member="pcm.h::snd_pcm_format_float" ref="ga36ae70bef5bfd5e7ecc743f6a4d46cb5" args="(snd_pcm_format_t format)" -->
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<td class="memname">int snd_pcm_format_float </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
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<div class="memdoc">
<p>Return float info for a PCM sample format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 non float, 1 float </dd></dl>
</div>
</div>
<a class="anchor" id="ga5a52bb63323f463198dea3f3c6aca571"></a><!-- doxytag: member="pcm.h::snd_pcm_format_linear" ref="ga5a52bb63323f463198dea3f3c6aca571" args="(snd_pcm_format_t format)" -->
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<td class="memname">int snd_pcm_format_linear </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return linear info for a PCM sample format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 non linear, 1 linear </dd></dl>
<dl><dt><b>Examples: </b></dt><dd><a class="el" href="_2test_2pcm_8c-example.html#a60">/test/pcm.c</a>.</dd>
</dl>
</div>
</div>
<a class="anchor" id="ga89537d0a972fa124051f6ba1a78c4bfa"></a><!-- doxytag: member="pcm.h::snd_pcm_format_little_endian" ref="ga89537d0a972fa124051f6ba1a78c4bfa" args="(snd_pcm_format_t format)" -->
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<td class="memname">int snd_pcm_format_little_endian </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return endian info for a PCM sample format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 big endian, 1 little endian, a negative error code if endian independent </dd></dl>
</div>
</div>
<a class="anchor" id="gaa3e0ff7560342e5af2b5c7bd2d63a307"></a><!-- doxytag: member="pcm.h::snd_pcm_format_physical_width" ref="gaa3e0ff7560342e5af2b5c7bd2d63a307" args="(snd_pcm_format_t format)" -->
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<td class="memname">int snd_pcm_format_physical_width </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
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<p>Return bits needed to store a PCM sample. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Sample format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>bits per sample, a negative error code if not applicable </dd></dl>
<dl><dt><b>Examples: </b></dt><dd><a class="el" href="_2test_2pcm_8c-example.html#a6">/test/pcm.c</a>.</dd>
</dl>
</div>
</div>
<a class="anchor" id="ga82631361cf1c1d13af207beb59cf97ac"></a><!-- doxytag: member="pcm.h::snd_pcm_format_set_silence" ref="ga82631361cf1c1d13af207beb59cf97ac" args="(snd_pcm_format_t format, void *buf, unsigned int samples)" -->
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<td class="memname">int snd_pcm_format_set_silence </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em>, </td>
</tr>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">void * </td>
<td class="paramname"> <em>data</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">unsigned int </td>
<td class="paramname"> <em>samples</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
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<p>Silence a PCM samples buffer. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Sample format </td></tr>
<tr><td valign="top"></td><td valign="top"><em>data</em> </td><td>Buffer </td></tr>
<tr><td valign="top"></td><td valign="top"><em>samples</em> </td><td>Samples count </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 if successful or a negative error code </dd></dl>
<dl><dt><b>Examples: </b></dt><dd><a class="el" href="_2test_2latency_8c-example.html#a47">/test/latency.c</a>.</dd>
</dl>
</div>
</div>
<a class="anchor" id="ga8b88181b11a026da55897a926d56034a"></a><!-- doxytag: member="pcm.h::snd_pcm_format_signed" ref="ga8b88181b11a026da55897a926d56034a" args="(snd_pcm_format_t format)" -->
<div class="memitem">
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<td class="memname">int snd_pcm_format_signed </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return sign info for a PCM sample linear format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 unsigned, 1 signed, a negative error code if format is not linear </dd></dl>
</div>
</div>
<a class="anchor" id="ga812a6458ab7759b750d6954050c75bb2"></a><!-- doxytag: member="pcm.h::snd_pcm_format_silence" ref="ga812a6458ab7759b750d6954050c75bb2" args="(snd_pcm_format_t format)" -->
<div class="memitem">
<div class="memproto">
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<td class="memname">u_int8_t snd_pcm_format_silence </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return 8 bit expressing silence for a PCM sample format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Sample format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>silence 8 bit word </dd></dl>
</div>
</div>
<a class="anchor" id="ga6602d717534a0b6857f461fef1d8b37c"></a><!-- doxytag: member="pcm.h::snd_pcm_format_silence_16" ref="ga6602d717534a0b6857f461fef1d8b37c" args="(snd_pcm_format_t format)" -->
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<td class="memname">u_int16_t snd_pcm_format_silence_16 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return 16 bit expressing silence for a PCM sample format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Sample format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>silence 16 bit word </dd></dl>
</div>
</div>
<a class="anchor" id="gafbf8a883e8b7c38b94df561e0169aef4"></a><!-- doxytag: member="pcm.h::snd_pcm_format_silence_32" ref="gafbf8a883e8b7c38b94df561e0169aef4" args="(snd_pcm_format_t format)" -->
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<div class="memproto">
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<td class="memname">u_int32_t snd_pcm_format_silence_32 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return 32 bit expressing silence for a PCM sample format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Sample format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>silence 32 bit word </dd></dl>
</div>
</div>
<a class="anchor" id="ga79524557a85d7bbee12d315925e702b3"></a><!-- doxytag: member="pcm.h::snd_pcm_format_silence_64" ref="ga79524557a85d7bbee12d315925e702b3" args="(snd_pcm_format_t format)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">u_int64_t snd_pcm_format_silence_64 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return 64 bit expressing silence for a PCM sample format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Sample format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>silence 64 bit word </dd></dl>
</div>
</div>
<a class="anchor" id="ga5953a58f024f8cf762a9e4dae6b09502"></a><!-- doxytag: member="pcm.h::snd_pcm_format_size" ref="ga5953a58f024f8cf762a9e4dae6b09502" args="(snd_pcm_format_t format, size_t samples)" -->
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<div class="memproto">
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<tr>
<td class="memname">ssize_t snd_pcm_format_size </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t </td>
<td class="paramname"> <em>samples</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return bytes needed to store a quantity of PCM sample. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Sample format </td></tr>
<tr><td valign="top"></td><td valign="top"><em>samples</em> </td><td>Samples count </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>bytes needed, a negative error code if not integer or unknown </dd></dl>
</div>
</div>
<a class="anchor" id="ga8cd4e3ecc963942457e3b1b6f7661a90"></a><!-- doxytag: member="pcm.h::snd_pcm_format_unsigned" ref="ga8cd4e3ecc963942457e3b1b6f7661a90" args="(snd_pcm_format_t format)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
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<td class="memname">int snd_pcm_format_unsigned </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return sign info for a PCM sample linear format. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 signed, 1 unsigned, a negative error code if format is not linear </dd></dl>
<dl><dt><b>Examples: </b></dt><dd><a class="el" href="_2test_2pcm_8c-example.html#a8">/test/pcm.c</a>.</dd>
</dl>
</div>
</div>
<a class="anchor" id="ga8d4e07f2d68cc16f607857ed8a222a29"></a><!-- doxytag: member="pcm.h::snd_pcm_format_width" ref="ga8d4e07f2d68cc16f607857ed8a222a29" args="(snd_pcm_format_t format)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int snd_pcm_format_width </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8">snd_pcm_format_t</a> </td>
<td class="paramname"> <em>format</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Return nominal bits per a PCM sample. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>format</em> </td><td>Sample format </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>bits per sample, a negative error code if not applicable </dd></dl>
<dl><dt><b>Examples: </b></dt><dd><a class="el" href="_2test_2latency_8c-example.html#a36">/test/latency.c</a>, and <a class="el" href="_2test_2pcm_8c-example.html#a5">/test/pcm.c</a>.</dd>
</dl>
</div>
</div>
<a class="anchor" id="gac05ac2b7c6e25986a71792392ff90b83"></a><!-- doxytag: member="pcm.h::snd_pcm_frames_to_bytes" ref="gac05ac2b7c6e25986a71792392ff90b83" args="(snd_pcm_t *pcm, snd_pcm_sframes_t frames)" -->
<div class="memitem">
<div class="memproto">
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<td class="memname">ssize_t snd_pcm_frames_to_bytes </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> * </td>
<td class="paramname"> <em>pcm</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#ga71cdfa37e258d2210b8bd0216bf0c36c">snd_pcm_sframes_t</a> </td>
<td class="paramname"> <em>frames</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Convert frames in bytes for a PCM. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>pcm</em> </td><td>PCM handle </td></tr>
<tr><td valign="top"></td><td valign="top"><em>frames</em> </td><td>quantity in frames </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>quantity expressed in bytes </dd></dl>
</div>
</div>
<a class="anchor" id="gae3669a4326ce185f4261d7bf96900f3f"></a><!-- doxytag: member="pcm.h::snd_pcm_samples_to_bytes" ref="gae3669a4326ce185f4261d7bf96900f3f" args="(snd_pcm_t *pcm, long samples)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">ssize_t snd_pcm_samples_to_bytes </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> * </td>
<td class="paramname"> <em>pcm</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">long </td>
<td class="paramname"> <em>samples</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Convert samples in bytes for a PCM. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>pcm</em> </td><td>PCM handle </td></tr>
<tr><td valign="top"></td><td valign="top"><em>samples</em> </td><td>quantity in samples </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>quantity expressed in bytes </dd></dl>
</div>
</div>
</div>
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