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<DIV><FONT size=2>I downloaded speex-1.2beta3-win32 binaries, and used the
speexenc.exe and speexdec to process the file male.wav </FONT><FONT
size=2>download from </FONT><FONT size=2><A
href="http://speex.org/samples">http://speex.org/samples</A></FONT></DIV>
<DIV><FONT size=2>
<DIV><FONT size=2>I used both the narrowband and ultra-wideband
mode:</FONT></DIV>
<DIV> </DIV>
<DIV>>speexenc -n --quality 3 male.wav n3.spx<BR>Encoding 8000 Hz audio using
narrowband mode (mono)</DIV>
<DIV> </DIV>
<DIV>>speexdec n3.spx n3.wav<BR>Decoding 8000 Hz audio using narrowband mode
(mono)<BR>Encoded with Speex speex-1.2beta3</DIV>
<DIV> </DIV>
<DIV>>speexenc -u --quality 3 male.wav u3.spx<BR>Warning: Trying to encode in
ultra-wideband (sub-band CELP) at 8000 Hz. I'll do<BR>it but I suggest you try
narrowband instead<BR>Encoding 8000 Hz audio using ultra-wideband (sub-band
CELP) mode (mono)</DIV>
<DIV> </DIV>
<DIV>>speexdec u3.spx u3.wav<BR>Decoding 8000 Hz audio using ultra-wideband
(sub-band CELP) mode (mono)<BR>Encoded with Speex speex-1.2beta3</DIV>
<DIV> </DIV>
<DIV>I believe the ultra-wideband mode would produce more compressed data and
better voice quality than </DIV>
<DIV><FONT size=2>the narrowband mode. However, I noticed that the facts is
contrary: the compressed file u3.spx is smaller than the n3.spx, and the quality
of u3.wav are worse than n3.wav. The source file and output files are
attached.</FONT></DIV>
<DIV> </DIV>
<DIV>Is there something wrong with them ? Could you help me explain this
phenomenon?</DIV>
<DIV> </DIV>
<DIV>Regards,</DIV>
<DIV>Fred Young</DIV>
<DIV> </DIV></FONT></DIV></BODY></HTML>