[FFmpeg-devel] [PATCH] avutil/rational: Document what is to be expected from av_d2q() of doubles representing rational numbers

[Michael Niedermayer]

On Wed, Jan 31, 2024 at 09:30:44PM +0100, epirat07 at gmail.com wrote:
> 
> 
> On 31 Jan 2024, at 20:47, Michael Niedermayer wrote:
> 
> > Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> > ---
> >  libavutil/rational.h | 4 ++++
> >  1 file changed, 4 insertions(+)
> >
> > diff --git a/libavutil/rational.h b/libavutil/rational.h
> > index 8cbfc8e0669..c6ac9fb1d91 100644
> > --- a/libavutil/rational.h
> > +++ b/libavutil/rational.h
> > @@ -168,6 +168,10 @@ static av_always_inline AVRational av_inv_q(AVRational q)
> >   * In case of infinity, the returned value is expressed as `{1, 0}` or
> >   * `{-1, 0}` depending on the sign.
> >   *
> > + * In general rational numbers with |num| <= 1<<26 && |den| <= 1<<26
> > + * can be recovered exactly from their double representation.
> > + * (no exceptions where found within 100M random ones)
> 
> I think you meant „were“ here instead of „where“?

fixed
also tested 1B more cases
and 1<<27 as a limit btw fails as is to be expected fro the amount
of bits in the mantisse

thx

[...]
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Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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