[FFmpeg-devel] [PATCH] nellymoser: user float literals for table

[Tristan Matthews]

On Sat, May 27, 2023 at 8:17 AM Andreas Rheinhardt
<andreas.rheinhardt at outlook.com> wrote:
>
> Tristan Matthews:
> > ---
> >  libavcodec/nellymoser.c | 36 ++++++++++++++++++------------------
> >  1 file changed, 18 insertions(+), 18 deletions(-)
> >
> > diff --git a/libavcodec/nellymoser.c b/libavcodec/nellymoser.c
> > index 66c5f83a56..fa22b79909 100644
> > --- a/libavcodec/nellymoser.c
> > +++ b/libavcodec/nellymoser.c
> > @@ -39,30 +39,30 @@
> >  #include "nellymoser.h"
> >
> >  const float ff_nelly_dequantization_table[127] = {
> > - 0.0000000000,
> > + 0.0000000000f,
> >
> > --0.8472560048, 0.7224709988,
> > +-0.8472560048f, 0.7224709988f,
> >
> > --1.5247479677,-0.4531480074, 0.3753609955, 1.4717899561,
> > +-1.5247479677f,-0.4531480074f, 0.3753609955f, 1.4717899561f,
> >
> > --1.9822579622,-1.1929379702,-0.5829370022,-0.0693780035, 0.3909569979, 0.9069200158, 1.4862740040, 2.2215409279,
> > +-1.9822579622f,-1.1929379702f,-0.5829370022f,-0.0693780035f, 0.3909569979f, 0.9069200158f, 1.4862740040f, 2.2215409279f,
> >
> > --2.3887870312,-1.8067539930,-1.4105420113,-1.0773609877,-0.7995010018,-0.5558109879,-0.3334020078,-0.1324490011,
> > - 0.0568020009, 0.2548770010, 0.4773550034, 0.7386850119, 1.0443060398, 1.3954459429, 1.8098750114, 2.3918759823,
> > +-2.3887870312f,-1.8067539930f,-1.4105420113f,-1.0773609877f,-0.7995010018f,-0.5558109879f,-0.3334020078f,-0.1324490011f,
> > + 0.0568020009f, 0.2548770010f, 0.4773550034f, 0.7386850119f, 1.0443060398f, 1.3954459429f, 1.8098750114f, 2.3918759823f,
> >
> > --2.3893830776,-1.9884680510,-1.7514040470,-1.5643119812,-1.3922129869,-1.2164649963,-1.0469499826,-0.8905100226,
> > --0.7645580173,-0.6454579830,-0.5259280205,-0.4059549868,-0.3029719889,-0.2096900046,-0.1239869967,-0.0479229987,
> > - 0.0257730000, 0.1001340002, 0.1737180054, 0.2585540116, 0.3522900045, 0.4569880068, 0.5767750144, 0.7003160119,
> > - 0.8425520062, 1.0093879700, 1.1821349859, 1.3534560204, 1.5320819616, 1.7332619429, 1.9722349644, 2.3978140354,
> > +-2.3893830776f,-1.9884680510f,-1.7514040470f,-1.5643119812f,-1.3922129869f,-1.2164649963f,-1.0469499826f,-0.8905100226f,
> > +-0.7645580173f,-0.6454579830f,-0.5259280205f,-0.4059549868f,-0.3029719889f,-0.2096900046f,-0.1239869967f,-0.0479229987f,
> > + 0.0257730000f, 0.1001340002f, 0.1737180054f, 0.2585540116f, 0.3522900045f, 0.4569880068f, 0.5767750144f, 0.7003160119f,
> > + 0.8425520062f, 1.0093879700f, 1.1821349859f, 1.3534560204f, 1.5320819616f, 1.7332619429f, 1.9722349644f, 2.3978140354f,
> >
> > --2.5756309032,-2.0573320389,-1.8984919786,-1.7727810144,-1.6662600040,-1.5742180347,-1.4993319511,-1.4316639900,
> > --1.3652280569,-1.3000990152,-1.2280930281,-1.1588579416,-1.0921250582,-1.0135740042,-0.9202849865,-0.8287050128,
> > --0.7374889851,-0.6447759867,-0.5590940118,-0.4857139885,-0.4110319912,-0.3459700048,-0.2851159871,-0.2341620028,
> > --0.1870580018,-0.1442500055,-0.1107169986,-0.0739680007,-0.0365610011,-0.0073290002, 0.0203610007, 0.0479039997,
> > - 0.0751969963, 0.0980999991, 0.1220389977, 0.1458999962, 0.1694349945, 0.1970459968, 0.2252430022, 0.2556869984,
> > - 0.2870100141, 0.3197099864, 0.3525829911, 0.3889069855, 0.4334920049, 0.4769459963, 0.5204820037, 0.5644530058,
> > - 0.6122040153, 0.6685929894, 0.7341650128, 0.8032159805, 0.8784040213, 0.9566209912, 1.0397069454, 1.1293770075,
> > - 1.2211159468, 1.3080279827, 1.4024800062, 1.5056819916, 1.6227730513, 1.7724959850, 1.9430880547, 2.2903931141
> > +-2.5756309032f,-2.0573320389f,-1.8984919786f,-1.7727810144f,-1.6662600040f,-1.5742180347f,-1.4993319511f,-1.4316639900f,
> > +-1.3652280569f,-1.3000990152f,-1.2280930281f,-1.1588579416f,-1.0921250582f,-1.0135740042f,-0.9202849865f,-0.8287050128f,
> > +-0.7374889851f,-0.6447759867f,-0.5590940118f,-0.4857139885f,-0.4110319912f,-0.3459700048f,-0.2851159871f,-0.2341620028f,
> > +-0.1870580018f,-0.1442500055f,-0.1107169986f,-0.0739680007f,-0.0365610011f,-0.0073290002f, 0.0203610007f, 0.0479039997f,
> > + 0.0751969963f, 0.0980999991f, 0.1220389977f, 0.1458999962f, 0.1694349945f, 0.1970459968f, 0.2252430022f, 0.2556869984f,
> > + 0.2870100141f, 0.3197099864f, 0.3525829911f, 0.3889069855f, 0.4334920049f, 0.4769459963f, 0.5204820037f, 0.5644530058f,
> > + 0.6122040153f, 0.6685929894f, 0.7341650128f, 0.8032159805f, 0.8784040213f, 0.9566209912f, 1.0397069454f, 1.1293770075f,
> > + 1.2211159468f, 1.3080279827f, 1.4024800062f, 1.5056819916f, 1.6227730513f, 1.7724959850f, 1.9430880547f, 2.2903931141f
> >  };
> >
> >  const uint8_t ff_nelly_band_sizes_table[NELLY_BANDS] = {
>
> What's the point of this? Has some compiler started emitting warnings
> about the lossy double->float conversions?

No, just my eyeballs. There are other places in the encoder/decoder
with double to float conversions but changing these changed the bias
of some expressions (e.g., the initialization of pow_table) so I
thought I'd start with this first unless there was no interest.

Best,
-t

>
> - Andreas
>
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