[Speex-dev] white noise problem when using -DFIXED_POINT

[speex-dev at aerodrome.us]

Jean-Marc Valin wrote:
> On mar, 2004-09-14 at 16:31 -0700, wrote:
> 
>>Hi there.  We're trying to build a speex decoder for Palm OS (i.e. ARM7).
>>
>>No major problems porting thus far, but when compiling the speex modules with -DFIXED_POINT all the silent parts of the output are replaced with what sounds like high-power white noise.  The spoken parts sound great, but all the silent parts in between speaking just sounds like white noise.
>>
>>We're using speex 1.1.6, and current libogg sources pulled down from subversion.
> 
> 
> It's difficult to say with only that info. Have you tried the same file
> on an x86 (with and without FIXED_POINT) and comparing the results. If
> you still can't find the problem, please post the file somewhere (along
> with the encoded version) and I'll have a look at it. Oh, and are you
> using speexenc/speexdec or you own encoder and decoder?
> 
> 	Jean-Marc

Jean-Marc,

Thanks for the quick reply, and sorry for eliding some of the details.  Our test builds thus far have indeed been on x86.  I reproduced the white noise condition described above using unmodified speexdec from speex 1.1.6, configured with --enable-fixed-point.  The output sounds okay when configured without fixed point support.

As I mentioned, we're using speex 1.1.6, current svn libogg, and gcc 2.95.4.

Here is one of the files that seems to exhibit the problem:
http://owen.theemrys.com/speex/0102.spx

Thanks in advance for any information.  I've spent the last few hours combing the list archives, but nothing seems to stand out.

Best regards,
Owen