[FFmpeg-devel] [PATCH] remove duplicate initialization of ff_cos_tabs in rdft.c

Reimar Döffinger Reimar.Doeffinger
Thu Oct 15 12:10:28 CEST 2009


On Thu, Oct 15, 2009 at 12:03:39PM +0200, Reimar D?ffinger wrote:
> Even worse, it will initialize it with possibly slightly different
> values (fft.c uses tab[m/2-i] = tab[i]; which IMO is a rather good idea,
> and would be an even better on for sin, since sin() is far more precise
> close to 0).

Ignore that part, rdft only uses half of the array, so it is the same
formula, except that the sign of the argument to cos can be inverted,
and for sin it only uses values close to 0.
The proposed patch still should be ok, though it could use a
#if !CONFIG_HARDCODED_TABLES alternatively



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