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这个程序开发于C#环境中

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<ul class="download">
<li><a href="http://www.codeproject.com/KB/audio-video/SoundViewer/SoundViewer.zip">Download demo project - 28.6 KB</a> </li>

<li><a href="http://www.codeproject.com/KB/audio-video/SoundViewer/SoundViewerSource.zip">Download source files - 27.6 KB</a> </li>
</ul>
<img alt="Screenshot - SoundViewer.jpg" src="SoundViewer.aspx_files/SoundViewer.jpg" width="598" border="0" height="645"> 
<h2>Introduction</h2>

<p>This project demonstrates the use of the Fast Fourier Transform and
Windows GDI to produce near real-time visualizations of the time and
frequency domains of sound.</p>

<h2>Background</h2>

<p>While looking for information on signal processing for a robotics
project, it became apparent that examples written in C# were hard to
find. This led me to create some of my own classes, which I have
provided here for this demonstration.</p>

<h2>Using the Code</h2>

<p>Audio input for this demonstration is provided by the <code>Wave</code> classes developed by Ianier Munoz. <code>Wave</code> samples are further processed using the <code>AudioFrame</code> class.</p>

<pre lang="cs"><span class="code-keyword">class</span> AudioFrame
{
    <span class="code-keyword">private</span> Bitmap _canvasTimeDomain;
    <span class="code-keyword">private</span> Bitmap _canvasFrequencyDomain;
    <span class="code-keyword">private</span> <span class="code-keyword">double</span>[] _waveLeft;
    <span class="code-keyword">private</span> <span class="code-keyword">double</span>[] _waveRight;
    <span class="code-keyword">private</span> <span class="code-keyword">double</span>[] _fftLeft;
    <span class="code-keyword">private</span> <span class="code-keyword">double</span>[] _fftRight;
    <span class="code-keyword">private</span> SignalGenerator _signalGenerator;
    <span class="code-keyword">private</span> <span class="code-keyword">bool</span> _isTest = <span class="code-keyword">false</span>;
    <span class="code-keyword">public</span> AudioFrame(<span class="code-keyword">bool</span> isTest)
    {