This was reported by me (and most likely others). Here is
the exchange about this. The reason the problem is
visible in Delphi is that Borland (C++ and Delphi)
initialize the FPU differently from other RTLs.
Also, there is another problem that will be visible with
Delphi
---------------------------------------------------------
-------------
Yes, that's definitely a bug in the vbr code, there's an
easy fix for that. Just replace:
qual += .3*log(ener/60000.0);
with
qual += .3*log((ener+1)/60000.0);
Jean-Marc
==========================================================On Mon, 2005-12-12 at
18:06 -0800, Alex Bakaev wrote:> Hello!
>
> I'm getting SING errors from the log() function. Here
is the code > inside the vbr_analysis() function.
>
> if (ener<60000)
> {
> if (vbr->consec_noise>2)
> qual-=0.5*(log(3.0 +
vbr->consec_noise)-log(3)); > if (ener<10000&&vbr->consec_noise>2)
> qual-=0.5*(log(3.0 +
vbr->consec_noise)-log(3)); > if (qual<0)
> qual=0;
> qual += .3*log(ener/60000.0);
> }
>
> Inspecting the values shows that 'ener' is zero, which
leads to the > error.
>
> The question I have is if the code above should
explicitly be checking > for zero? Or I have an issue with my compiler screwing
something up?>
> The error doesn't occur constantly, but frequently
enough to be a huge > nuissance.
>
> Thanks in advance,
> Alex
>
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+++> It seems that using a different compiler (I assume the
development is > done with MSC) uncovers various issues with the
floating point.
No, all development is done on gcc/Linux.
> Here is the second one I'm seeing - DOMAIN error from
sqrt().>
> In the open_loop_nbest_pitch(), this line:
>
> g = DIV32(corr[i-start], 10
>
+SHR32(MULT16_16(spx_sqrt(e0),spx_sqrt(energy[i-start])),
6));
change that to:
g = DIV32(corr[i-start],
10+SHR32(MULT16_16(spx_sqrt(e0),spx_sqrt(1
+energy[i-start])),6));
(note the "1+" in the spx_sqrt)
As for this appearing only on some version/compiler
configurations, the only explanation is sheer luck (order
in which the float operations are done and when it goes
to registers).
Jean-Marc
