GuidoMidi2PianoRoll </td></tr>
    <tr><td class="paramname">voiceNum</td><td>the voice number (first voice is number 1) </td></tr>
    <tr><td class="paramname">r</td><td>the red param of RGB color </td></tr>
    <tr><td class="paramname">g</td><td>the green param of RGB color </td></tr>
    <tr><td class="paramname">b</td><td>the blue param of RGB color </td></tr>
    <tr><td class="paramname">a</td><td>the alpha param of RGB color </td></tr>
  </table>
  </dd>
</dl>
<dl class="return"><dt><b>Returns:</b>