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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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<dl compact><dt><b>Returns:</b></dt><dd>The decoded PCM value. This is in the format specified by <a class="el" href="classG726.html#a2">SetLaw()</a>.</dd></dl>
<dl compact><dt><b>See also:</b></dt><dd><a class="el" href="group__g726.html#ga0">IMPLEMENT_G191_BUGS</a></dd></dl>
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<a class="anchor" name="a6" 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>
          <td class="md" valign="top">(&nbsp;</td>
          <td class="md" nowrap valign="top">void *&nbsp;</td>
          <td class="mdname" nowrap> <em>dst</em>, </td>
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          <td class="md" nowrap align="right"></td>
          <td class="md"></td>
          <td class="md" nowrap>int&nbsp;</td>
          <td class="mdname" nowrap> <em>dstOffset</em>, </td>
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          <td class="md" nowrap align="right"></td>
          <td class="md"></td>
          <td class="md" nowrap>const void *&nbsp;</td>
          <td class="mdname" nowrap> <em>src</em>, </td>
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          <td class="md" nowrap align="right"></td>
          <td class="md"></td>
          <td class="md" nowrap><a class="el" href="group__integers.html#ga6">uint</a>&nbsp;</td>
          <td class="mdname" nowrap> <em>srcSize</em></td>
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          <td class="md"></td>
          <td class="md">)&nbsp;</td>
          <td class="md" colspan="2"></td>
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<p>
Encode a buffer of 16 bit uniform PCM values into ADPCM values.<p>
Each ADPCM value only occupies the minimum number of bits required and successive values occupy adjacent bit positions. E.g. Four 3 bit ADPCM values (A,B,C,D) are stored in two successive bytes like this: 1st byte: ccbbbaaa 2nd byte: ----dddc. Note that any unused bits in the last byte are set to zero.<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>
  <table border="0" cellspacing="2" cellpadding="0">
    <tr><td valign="top"></td><td valign="top"><em>dst</em>&nbsp;</td><td>Pointer to location to store ADPCM values. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>dstOffset</em>&nbsp;</td><td>Offset from <em>dst</em>, in number-of-bits, at which the decoded values will be stored. I.e. the least significant bit of the first ADPCM value will be stored in byte <div class="fragment"><pre class="fragment">     dst[dstOffset&gt;&gt;3]   
</pre></div> at bit position <div class="fragment"><pre class="fragment">     dstOffset&amp;7         
</pre></div> Where the bit 0 is the least significant bit in a byte and bit 7 is the most significant bit. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>src</em>&nbsp;</td><td>Pointer to the buffer of PCM values to be converted. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>srcSize</em>&nbsp;</td><td>The size in bytes of the buffer at <em>src</em>. Must be a multiple of the size of a single PCM sample.</td></tr>
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</dl>
<dl compact><dt><b>Returns:</b></dt><dd>The number of bits were stored in the <em>dst</em> buffer.</dd></dl>
<dl compact><dt><b>Since:</b></dt><dd>2005-02-13</dd></dl>
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<a class="anchor" name="a7" 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>
          <td class="md" valign="top">(&nbsp;</td>
          <td class="md" nowrap valign="top">void *&nbsp;</td>
          <td class="mdname" nowrap> <em>dst</em>, </td>
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          <td class="md" nowrap align="right"></td>
          <td class="md"></td>
          <td class="md" nowrap>const void *&nbsp;</td>
          <td class="mdname" nowrap> <em>src</em>, </td>
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          <td class="md" nowrap align="right"></td>
          <td class="md"></td>
          <td class="md" nowrap>int&nbsp;</td>
          <td class="mdname" nowrap> <em>srcOffset</em>, </td>
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          <td class="md" nowrap align="right"></td>
          <td class="md"></td>
          <td class="md" nowrap><a class="el" href="group__integers.html#ga6">uint</a>&nbsp;</td>
          <td class="mdname" nowrap> <em>srcSize</em></td>
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          <td class="md"></td>
          <td class="md">)&nbsp;</td>
          <td class="md" colspan="2"></td>
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<p>
Decode a buffer of ADPCM values into 16 bit uniform PCM values.<p>
Each ADPCM value only occupies the minimum number of bits required and successive values occupy adjacent bit positions. E.g. Four 3 bit ADPCM values (A,B,C,D) are stored in two successive bytes like this: 1st byte: ccbbbaaa 2nd byte: ----dddc.<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>
  <table border="0" cellspacing="2" cellpadding="0">
    <tr><td valign="top"></td><td valign="top"><em>dst</em>&nbsp;</td><td>Pointer to location to store PCM values. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>src</em>&nbsp;</td><td>Pointer to the buffer of ADPCM values to be converted. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>srcOffset</em>&nbsp;</td><td>Offset from <em>src</em>, in number-of-bits, from which the ADPCM values will be read. I.e. the least significant bit of the first ADPCM value will be read from byte <div class="fragment"><pre class="fragment">     src[srcOffset&gt;&gt;3]   
</pre></div> at bit position <div class="fragment"><pre class="fragment">     srcOffset&amp;7         
</pre></div> Where the bit 0 is the least significant bit in a byte and bit 7 is the most significant bit. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>srcSize</em>&nbsp;</td><td>The number of bits to be read from the buffer at <em>src</em>. Must be a multiple of the size of a single ADPCM value.</td></tr>
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<dl compact><dt><b>Returns:</b></dt><dd>The number of bytes which were stored in the <em>dst</em> buffer.</dd></dl>
<dl compact><dt><b>See also:</b></dt><dd><a class="el" href="group__g726.html#ga0">IMPLEMENT_G191_BUGS</a></dd></dl>
<dl compact><dt><b>Since:</b></dt><dd>2005-02-13</dd></dl>
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<a class="anchor" name="d14" doxytag="G726::EncodeDecode"></a><p>
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          <td class="md" nowrap valign="top"><a class="el" href="group__integers.html#ga6">uint</a> G726::EncodeDecode           </td>
          <td class="md" valign="top">(&nbsp;</td>
          <td class="md" nowrap valign="top"><a class="el" href="group__integers.html#ga6">uint</a>&nbsp;</td>
          <td class="mdname" nowrap> <em>input</em>, </td>
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          <td class="md" nowrap align="right"></td>
          <td class="md"></td>
          <td class="md" nowrap>bool&nbsp;</td>
          <td class="mdname" nowrap> <em>encode</em></td>
        </tr>
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          <td class="md"></td>
          <td class="md">)&nbsp;</td>
          <td class="md" colspan="2"><code> [private]</code></td>
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<p>
The top level method which implements the complete algorithm for both encoding and decoding. 
<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
  <table border="0" cellspacing="2" cellpadding="0">
    <tr><td valign="top"></td><td valign="top"><em>input</em>&nbsp;</td><td>Either the PCM input to the encoder or the ADPCM input to the decoder. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>encode</em>&nbsp;</td><td>A flag which if true makes this method perform the encode function. If the flag is false then the decode function is performed. </td></tr>
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</dl>
<dl compact><dt><b>Returns:</b></dt><dd>Either the ADPCM output to the encoder or the PCM output to the decoder. </dd></dl>
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<hr>The documentation for this class was generated from the following files:<ul>
<li><a class="el" href="G726_8h.html">G726.h</a><li><a class="el" href="G726_8cpp.html">G726.cpp</a></ul>
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