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G.726带测试和在DM642实现的完整工程。测试程序可修改自行填入数据。实现部分设计具体产品板的定义

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          <td class="md" nowrap valign="top">G726::G726           </td>
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          <td class="md" valign="top">&nbsp;)&nbsp;</td>
          <td class="md" nowrap><code> [inline]</code></td>
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<p>
Contructor which initialises the object to the reset state. <dl compact><dt><b>See also:</b></dt><dd><a class="el" href="classG726.html#a1">Reset()</a> </dd></dl>
<dl compact><dt><b>Since:</b></dt><dd>2005-02-13</dd></dl>
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<hr><h2>Member Function Documentation</h2>
<a class="anchor" name="a1" doxytag="G726::Reset"></a><p>
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          <td class="md" nowrap valign="top">EXPORT void G726::Reset           </td>
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<p>
Clears the internal state variables to their 'reset' values. Call this function before startings to decode/encode a new audio stream.    </td>
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<a class="anchor" name="a2" doxytag="G726::SetLaw"></a><p>
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          <td class="md" nowrap valign="top">EXPORT void G726::SetLaw           </td>
          <td class="md" valign="top">(&nbsp;</td>
          <td class="md" nowrap valign="top"><a class="el" href="classG726.html#w7">Law</a>&nbsp;</td>
          <td class="mdname1" valign="top" nowrap> <em>law</em>          </td>
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<p>
Set the encoding law used for encoder input and decoder output.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
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    <tr><td valign="top"></td><td valign="top"><em>law</em>&nbsp;</td><td>The encoding law.</td></tr>
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<a class="anchor" name="a3" doxytag="G726::SetRate"></a><p>
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          <td class="md" nowrap valign="top">EXPORT void G726::SetRate           </td>
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          <td class="md" nowrap valign="top"><a class="el" href="classG726.html#w8">Rate</a>&nbsp;</td>
          <td class="mdname1" valign="top" nowrap> <em>rate</em>          </td>
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<p>
Set the ADPCM bit-rate used for encoder output and decoder intput.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
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    <tr><td valign="top"></td><td valign="top"><em>rate</em>&nbsp;</td><td>The ADPCM bit-rate.</td></tr>
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<a class="anchor" name="a4" doxytag="G726::Encode"></a><p>
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          <td class="md" nowrap valign="top">EXPORT <a class="el" href="group__integers.html#ga6">uint</a> G726::Encode           </td>
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          <td class="md" nowrap valign="top"><a class="el" href="group__integers.html#ga6">uint</a>&nbsp;</td>
          <td class="mdname1" valign="top" nowrap> <em>pcm</em>          </td>
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<p>
Encodes a single PCM value as an ADPCM value.<p>
<dl compact><dt><b>Precondition:</b></dt><dd>The coding law and ADPCM bit-rate should have been previous initialised with <a class="el" href="classG726.html#a2">SetLaw()</a> and <a class="el" href="classG726.html#a3">SetRate()</a>.</dd></dl>
<dl compact><dt><b>Parameters:</b></dt><dd>
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    <tr><td valign="top"></td><td valign="top"><em>pcm</em>&nbsp;</td><td>The PCM value to encode. The bits in this value which lie outside the range of values for the currently set encoding law, are ignored.</td></tr>
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<dl compact><dt><b>Returns:</b></dt><dd>The encoded ADPCM value. The number of significant bits in this value are dependant on the bit-rate set by <a class="el" href="classG726.html#a3">SetRate()</a>. Unused bits are set to zero.</dd></dl>
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<a class="anchor" name="a5" doxytag="G726::Decode"></a><p>
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          <td class="md" nowrap valign="top">EXPORT <a class="el" href="group__integers.html#ga6">uint</a> G726::Decode           </td>
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          <td class="md" nowrap valign="top"><a class="el" href="group__integers.html#ga6">uint</a>&nbsp;</td>
          <td class="mdname1" valign="top" nowrap> <em>adpcm</em>          </td>
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<p>
Decodes a single ADPCM value into a PCM value.<p>
<dl compact><dt><b>Precondition:</b></dt><dd>The coding law and ADPCM bit-rate should have been previous initialised with <a class="el" href="classG726.html#a2">SetLaw()</a> and <a class="el" href="classG726.html#a3">SetRate()</a>.</dd></dl>
<dl compact><dt><b>Parameters:</b></dt><dd>
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    <tr><td valign="top"></td><td valign="top"><em>adpcm</em>&nbsp;</td><td>The ADPCM value to decode. The bits in this value which lie outside the range of values for the currently set bit-rate, are ignored.</td></tr>
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