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<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Hello,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>I
know my question has been asked before because I spent the last week searching
the web for how to use Speex in combination with WaveIn/WaveOut and I ran into
a few posts, but none of them answer the question. There is still a lot of
confusion how to use WaveIn/WaveOut and Speex by junior developers such as myself.
Even after examining code for SpeexDec and SpeexEnc, I cannot get clear sound
when I try to<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Get
PCM Char buffer from the microphone<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Encode
Char buffer using Speex<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Decode
Speex Char buffer into PCM char buffer<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Play
PCM char buffer using WaveOut<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>The
end-result is very distorted sound.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>I
use the following PCM format:<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'>waveFormat.nChannels = 1;<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'>waveFormat.nSamplesPerSec = 8000;<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>waveFormat.wBitsPerSample
= 8;<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Once
sound is aquired by the mic, I send it to Speex in a Char buffer. It looks
something like this:<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Encode(<span
style='color:blue'>char</span>* inBuffer, DWORD bufferLength)<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>...<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New";color:blue'>float</span><span style='font-size:10.0pt;
font-family:"Courier New"'>* input = <span style='color:blue'>new</span> <span
style='color:blue'>float</span>[frameSize];<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>ZeroMemory(input,
frameSize);<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>...<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>for(
)<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>{<o:p></o:p></span></p>
<p class=MsoNormal style='text-indent:.5in'><span style='font-size:10.0pt;
font-family:"Courier New"'>input[..] = inBuffer[..];<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>}<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>...<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>speex_encode(enc_state,
input, &bits);<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>int
bytesWritten = speex_bits_nbytes(&bits);<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>speex_bits_write(&bits,
encBuffer, bytesWritten);<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Then,
my decoding routine accepts the char buffer that was encoded with Speex:<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Decode(<span
style='color:blue'>char</span>* encBuffer, DWORD bufferLength)<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>...<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New";
color:blue'>float</span><span style='font-size:10.0pt;font-family:"Courier New"'>*
output = <span style='color:blue'>new</span> <span style='color:blue'>float</span>[frameSize];<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>...<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>speex_bits_read_from(&bits,
encBuffer + offset, bytesToRead);</span><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>speex_decode(dec_state,
&bits, output);<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>char*
outBuffer=...</span><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New";color:blue'>for</span><span style='font-size:10.0pt;
font-family:"Courier New"'>(UINT i = 0; i < frameSize; i++)<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'>{<o:p></o:p></span></p>
<p class=MsoNormal style='text-indent:.5in;text-autospace:none'><span
style='font-size:10.0pt;font-family:"Courier New"'>outBuffer[retValIndex] =
output[i];<o:p></o:p></span></p>
<p class=MsoNormal style='text-indent:.5in'><span style='font-size:10.0pt;
font-family:"Courier New"'>retValIndex++;<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>}</span><span
style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>When
I try to play outBuffer with waveOut, I can hear the voice “somewhere far”,
but there is a lot of distortion noise. Any help would be greatly appreciated!!!<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Thank
you,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Evgueni
Tsygankov<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><a
href="http://www.sqlanswers.com/">www.sqlanswers.com</a><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p>
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